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Review

Cucurbitacins as Potent Chemo-Preventive Agents: Mechanistic Insight and Recent Trends

1
Department of Biotechnology, Maharishi Markandeshwar Engineering College, Maharishi Markandeshwar (Deemed to be University), Mullana-Ambala 133207, India
2
Amity Institute of Environmental Sciences, Amity University, Noida 201303, India
3
Amity Institute of Environmental Toxicology, Safety and Management, Amity University, Noida 201303, India
4
Academy of Biology and Biotechnology, Southern Federal University, 344090 Rostov-on-Don, Russia
5
University Centre for Research and Development, University Institute of Pharmaceutical Sciences, Chandigarh University, Mohali 140413, India
6
NGO Praeventio, 50407 Tartu, Estonia
7
Department of Chemistry, Maharishi Markandeshwar University Sadopur, Ambala 134007, India
8
Division of Pathology, ICAR-Indian Veterinary Research Institute, Bareilly 243122, India
9
Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117600, Singapore
10
NUS Centre for Cancer Research (N2CR), Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore
*
Authors to whom correspondence should be addressed.
Biomolecules 2023, 13(1), 57; https://doi.org/10.3390/biom13010057
Submission received: 29 November 2022 / Revised: 21 December 2022 / Accepted: 22 December 2022 / Published: 27 December 2022
(This article belongs to the Collection Feature Papers in Section Molecular Medicine)

Abstract

:
Cucurbitacins constitute a group of cucumber-derived dietary lipids, highly oxidized tetracyclic triterpenoids, with potential medical uses. These compounds are known to interact with a variety of recognized cellular targets to impede the growth of cancer cells. Accumulating evidence has suggested that inhibition of tumor cell growth via induction of apoptosis, cell-cycle arrest, anti-metastasis and anti-angiogenesis are major promising chemo-preventive actions of cucurbitacins. Cucurbitacins may be a potential choice for investigations of synergism with other drugs to reverse cancer cells’ treatment resistance. The detailed molecular mechanisms underlying these effects include interactions between cucurbitacins and numerous cellular targets (Bcl-2/Bax, caspases, STAT3, cyclins, NF-κB, COX-2, MMP-9, VEGF/R, etc.) as well as control of a variety of intracellular signal transduction pathways. The current study is focused on the efforts undertaken to find possible molecular targets for cucurbitacins in suppressing diverse malignant processes. The review is distinctive since it presents all potential molecular targets of cucurbitacins in cancer on one common podium.

1. Introduction

Cancer is a huge global threat, representing a heavy burden to social systems and health care sectors all over the world. Moreover, over the past decades, both the incidence as well as mortality rates of malignant disorders have been increased, with a continuous sharp rise expected for further years [1]. This situation clearly indicates that current therapeutic tools for combating cancer are insufficient, inducing often also a wide range of adverse effects to the patients with already weakened health status [2,3,4]. Therefore, novel, safe and more efficient treatment modalities are highly needed and must be developed, whereas one possibility for this is to focus more on the natural plant-derived agents [5].
In ethnomedicine, natural products have been used for the management of both benign as well as malignant neoplasms already for centuries [6,7,8,9]. This approach has led to launching the screening program of plant-derived compounds in the US National Cancer Institute in the middle of the 20th century, resulting in the isolation and development of several anticancer drugs such as vincristine, vinblastine, and paclitaxel among others, currently approved for clinical use against different cancer types [10,11,12,13]. This success clearly demonstrates that nature is an important resource for anticancer agents, encouraging to continue such efforts.
Cucurbitacins (designated by the letters A, B, C, D, E, F, G, H, I, J, K, L, O, P, Q, R, S) constitute a class of natural triterpenoids [14]. These compounds can be found in many plants from the genera Bryonia, Cucurbita, Cucumis, Echinocystis, Luffa, Citrullus and Lagenaria, conferring a bitter taste in cucumber [14,15]. Several recent preclinical studies have demonstrated that this group of phytochemicals can exert antitumor activities in a variety of experimental models of different malignancies, including lung cancer [16], gastric cancer [17], colorectal cancer [18], liver cancer [19], pancreatic cancer [20], ovarian cancer [21], cervical cancer [22] and melanoma [23]. Such anticancer effects are achieved via interaction of cucurbitacins with multiple molecular targets and intervening in diverse cellular signaling cascades, suggesting that a high potential of this compound should be developed as a therapeutic tool.
To appreciate and draw more attention to these ancient molecules, this review article is focused on the different anticancer activities of cucurbitacins in diverse experimental model systems, describing anti-inflammatory, cell-cycle arresting, proapoptotic, antiangiogenic and antimetastatic effects of these triterpenoids. Moreover, co-effects of cucurbitacins with conventional cancer drugs are considered, presenting the most potent combinations for further studies. In addition, the possibilities to overcome the low bioavailability issues characteristic for natural compounds by modern nanotechnological methods are also discussed. In this way, the present review provides a strong basis for moving on with in vivo animal studies and human clinical trials, hopefully to apply cucurbitacins in the clinical settings in the future.

2. Chemistry of Cucurbitacins

Plants of the Cucurbitaceae family produce a class of biological substances that are known as cucurbitacins. Cucurbitacins are created by these plants to protect them from herbivores. Cucurbitacin A, B, C, D, E, F, I, L, 23, 24 dihydrocucurbitacin F, and hexanorcucurbitacin F, as well as the three acetylated derivatives, are the naturally occurring cucurbitacins [24]. Cucurbitacins are tetracyclic terpenes with steroidal structures in their chemical configuration. Cucurbitacins’ basic chemical structure is cucurbit-5-ene with a ring skeleton of 19(109)-abeo-10-lanost-5-ene (Figure 1). For instance, in the structure of cucurbitacin I (9,10,14-trimethyl-4,9-cyclo-9,10-secocholesta-2,5,23-triene) triene are replaced by hydroxy groups at positions 2, 16, 20 and 25 and oxo groups at positions 1, 11 and 22. This distinguishes the cucurbitacins from most other tetracyclic triterpenes. In all chemical structures of cucurbitacins, the presence of a 5,(6)-double bond is observed as a common characteristic. Cucurbitacins differ from steroidal nuclei in that their methyl group is located at carbon 9 instead of carbon 10 [14].

3. Absorption and Metabolism of Cucurbitacins

The presence of cucurbitacins is observed mainly in plant roots and fruits. They are a highly diverse group and divided into 12 categories, cucurbitacins A–T [25]. Less research has been conducted on cucurbitacins’ absorption, distribution, metabolism, and excretion; this is a topic that should be investigated considering the compound’s potential toxicity to mammals. [14]. Oral administration of cucurbitacin B (CuB) has been studied and shown to be slowly absorbed and metabolized in the gut [26]. CuE at a concentration of 100–200 μg/kg treatment had a plasma half-life of about 58–72% [27]. Similarly, oral bioavailability of CuB has been studied to be ~10% with plasma concentration ranging from 4.85 to 7.81 μg/L after 30 mins of oral dosing. After intravenous administration, it is distributed in large volume ~51.65 l/kg and exhibits a high tissue to plasma concentration ratios of ~60–280-folds in many organs. A negligible amount (~1%) of CuB was detected in urine and feces, and it was suggested that it probably undergoes biotransformation prior to excretion [28]. Studies have shown that they reach highest plasma concentration within 1.75 h and an elimination half-life of ~2.5 h. As oral delivery and absorption of cucurbitacins remain a great challenge, recent focus has been on the use of nano-micelles co-modified with cucurbitacins, which enhances the relative bioavailability of CuB by ~2.14–3.43 times [29]. However, further pharmacokinetic studies comprising metabolism and distribution of cucurbitacins are still required.

4. Anti-Cancer Mechanisms of Cucurbitacins

4.1. Apoptotic and Cell-Cycle Arrest

Apoptotic cell death can be triggered in cancer through internal and extrinsic processes, which converge on the control of caspase-dependent proteolysis of cellular proteins and DNA fragmentation [30,31,32]. Similarly, all tumor types have abnormal cell-cycle progression activity, which acts as a catalyst for carcinogenesis [33]. Recent research has shown that a variety of biological processes are regulated by cell-cycle proteins [34,35,36]. Therefore, numerous chemo-preventive FDA-drugs have been shown to mediate antitumor effects either via activation of apoptotic or cell-cycle arrest (Figure 2) signaling pathways [37,38,39]. For instance, results from Li et al. (2018) revealed that cucurbitacin I caused lung cancer (A549) cells to undergo excessive ERS, CHOP-Bax and caspase-12-dependent ERS-associated apoptosis [40]. In colorectal cancer (SW480 and Caco-2) cells, treatment with cucurbitacin B resulted in cell-cycle arrest at the G1 phase as well as decreased Cyclin D1 and Cyclin E1 levels. Both CRC cell lines underwent in vitro cell death when exposed to CuB, which was accompanied by caspase-3 and cleaved PARP [41]. Using triple negative breast cancer (TNBC), cucurbitacin E strongly boosted JNK activation while considerably decreasing AKT and ERK activation in MDA-MB-468 cells. It also significantly decreased expression of Cyclin D1, Survivin, XIAP, Bcl2 and Mcl-1 [42]. In the pancreatic cancer cell line Capan-1, CuD induced cell-cycle arrest and death via the ROS/p38 pathway [43]. Cucurbitacin I-induced cell death in ovarian cancer (SKOV3) included apoptosis, as evidenced by upregulated caspase 3 and BAX and a decrease in Bcl2 [21]. Flow cytometric measurement of DNA content and RT-PCR analyses suggested that cucurbitacin B caused G2/M arrest in human breast cancer cell lines (MDA-MB-231 and MCF-7) through elevated p21 expression [44]. Huang et al. showed that in human bladder cancer (T24) cells, cucurbitacin E-induced G2/M arrest was accompanied by a significant rise in p53 and p21 levels and a fall in the levels of STAT3, cyclin-dependent kinase 1 (CDK1) and cyclin B [45]. In addition, cucurbitacin E-induced G2/M phase arrest and death of T24 cells also depended on Fas/CD95 and mitochondria-dependent apoptotic pathways. Similarly, using other cancerous cell lines, cucurbitacins target the cell-cycle actions that involves growth inhibition, cell-cycle arrest at G2/M phase and induction of apoptosis [46]. Cucurbitacin I has been observed to suppress phosphotyrosine STAT3 in human cancerous lung cells [47]. Recently, it was observed to promote gastric cancer cell apoptosis by inducing the production of cellular ROS, as well as the endoplasmic reticulum stress pathway [40,48]. While cucurbitacin B, E and I have been observed to inhibit both JAK2 and STAT3 activation, cucurbitacin A and I have been reported to inhibit JAK2 and STAT3, respectively [47]. Treating Hep-2 cells with different concentrations of cucurbitacin B for various time intervals showed reduction in cell proliferation, cell-cycle distribution, and increased cell apoptosis in cancerous cell lines [46]. This study also stated that cucurbitacin B exhibited significant efficacy in inhibiting cell growth, arresting cell cycle at the G2/M phase, and inducing apoptosis in a dose- and time-dependent manner [46]. Similarly, cucurbitacins B, D, E were observed to inhibit proteins such as JAK-STAT3. They also inhibited mitogen-activated protein kinases (MAPK)- signaling pathways and tumor angiogenesis [48]. A study conducted on human umbilical vascular endothelial cell lines revealed cucurbitacin to significantly inhibit the proliferation, migration, and angiogenesis. It also blocked essential proteins such as Jak2-signal transducer, vascular endothelial growth factor receptor (VEGFR) and STAT3 signaling pathways [49]. Such studies have highlighted that the main mechanism involved in imparting the anti-tumorigenic potentials of cucurbitacins involves inhibition of the JAK/STAT3 signaling pathway, which plays an essential role in activation, proliferation, and maintenance of cancerous cells [14]. Another recent study has shown that treatment with 8 µM cucurbitacin IIb for 24 h remarkably inhibited the proliferation of HeLa and A549 tumor cells, with IC50 values of 7.3 and 7.8 µM, respectively, while increasing total apoptosis by 56.9 and 52.3%, respectively [50]. Another pathway by which cucurbitacin IIb induces apoptosis and cell-cycle arrest is by the regulating EGFR/MAPK pathway [51]. Similarly, cucurbitacin D was observed to regulate the levels of oncogenic signaling cascades, JAK/STAT, Wnt/β-catenin and associated non-coding RNAs in many cancer cell lines [52]. Recent studies have shown that CuIIb and cucurbitacin B induced apoptosis in cervical cancer cell lines by Nrf2 inhibition, whereas in lung cancer cell lines cucurbitacin B was responsible for suppressing growth and inducing apoptotic death by impeding IL-6/STAT3 signaling [21,53].

4.2. Antiangiogenic and Antimetastatic Mechanisms

The physiological process by which new blood vessels develop from pre-existing vessels is known as angiogenesis. Anti-angiogenesis causes suppression of tumor growth because of hunger and toxic waste buildup in its microenvironment [54,55]. The development and metastasis of the tumor have a major impact on the cancer vasculature (Figure 3). Vascular endothelial growth factors (VEGFs) are crucial protein regulators of angiogenesis and metastasis. Studies have shown that inhibiting the VEGFR2-mediated JAK/STAT3 pathway is considered as an effective approach to suppress angiogenesis [49]. Though many studies about the mechanism of cucurbitacins and angiogenesis are not well known, few studies have still shown that cucurbitacins such as cucurbitacin B, cucurbitacin D, cucurbitacin E and cucurbitacin I possess anti-angiogenesis properties [56,57]. CuB significantly inhibited angiogenesis, metastasis, and vascular development in dose-dependent manner in in vivo models and chick embryos [56]. CuE significantly inhibited human umbilical vascular endothelial cell (HUVEC) proliferation and angiogenesis by targeting the VEGFR2-mediated Jak2/STAT3 signaling pathway [49]. CuB has been observed to inhibit ERK1/2, prevent Raf-MEK-ERK from activating STAT3, which ultimately plays a key role in angiogenesis [58]. A similar effect of CuB was seen also in human breast cancer cell lines. It successfully inhibited angiogenesis by targeting the FAK/MMP-9 signaling axis [59]. CuB showed antimetastatic activity and targeted angiogenesis also in paclitaxel resistant A2780/Taxol ovarian cancer cells. It also suppressed angiogenesis by downregulating the expression of HIF-1 targets, VEGF, VEGFR2 phosphorylation and erythropoietin [56,60]. Another study revealed the effective use of CuE for anti-angiogenesis in Huh7 cells. It decreased the tube formation in HUVECs and was also responsible for inhibiting the process of neo-vascularization in CAM assays [61]. A recent study showed that CuE modulated the JAK/STAT3 pathways, which regulated the angiogenesis [62]. CuE has been also involved in inhibiting the KDR/VEGFR2-mediated pathway of angiogenesis [63]. Treating A549 cells with cucurbitacins for ~21 days showed positive results for inhibiting metastasis by regulating the levels of cyclooxygenase 2, matrix metalloproteinase 9, and cyclin D11 [64]. Similarly, other cucurbitacins were observed to inhibit angiogenesis in MDA-MB-231 and MCF-7 cancer cells by inhibiting the JAK/STAT pathways [65].

4.3. Anti-Inflammatory Mechanisms

Most malignancies’ growth and malignant progression are correlated with inflammation [66,67,68]. Both intrinsic and extrinsic inflammations have the potential to inhibit the immune system, which creates an ideal environment for the growth of tumors [69,70,71]. As a result, focusing on inflammation is a tempting strategy for both cancer therapy and cancer prevention [69,72]. Cucurbitacins have been observed to interact with proteins associated with inflammatory (Figure 4) pathways such as interleukins (IL)-6, IL-5, IL-1β, IL-12, IL-13 in a dose-dependent manner [73]. Dietary cucurbitacin E has been shown to reduce inflammation and immunosuppression by downregulating the NF-κB signaling pathway [74]. CuB has been studied to possess protective effects by reducing inflammatory responses on sepsis-induced acute lung injury in in vivo rat models. It significantly reduced the levels of TNF-α, IL-6, cytokine secretion and accumulation of inflammatory cells. It also regulated the levels of Ca2+, which play an essential role in inflammatory responses [75]. CuB inhibited inflammatory responses through targeting the SIRT1/IGFBPrP1/TGF β1 axis. It downregulated the expression levels of TGF β1, IGFBPrP1, and upregulated the expression of SIRT 1 [76]. Similarly, CuE decreased the levels of pro-inflammatory cytokines, such as IL-17 and IFN-γ, as well as the activities of the STAT3 and IL-17A-promoter in allo-reactive T cells [77]. CuE has been shown to inhibit skin inflammation and fibrosis by regulating the expression of α-Sma and Col-I in mice models [76]. Recently, it has also been demonstrated that CuE ameliorated lipopolysaccharide-evoked injuries and inflammation in bronchial epithelial cells by regulating the TLR4-NF-κB signaling. It was responsible for suppressing levels of inflammatory cytokine production, TNF-α, IL-6 and IL-8 [78]. Cucurbitacin B was observed to directly bind to toll-like receptor 4 (TLR4) and activate NLRP3 inflammasome, which further ultimately executed pyroptosis in A549 cells. CuB treatment has been observed to upregulate the protein expressions of IL-1β, GSDMD, HMGB1 and led to inhibition of generation of mitochondrial ROS and pyroptosis [79]. CuB was reported to sensitize CD133+ HepG2 cells in in vitro and in vivo models [80].

5. Synergistic Effects with Other Drugs

During cancer therapies, the side effects and long-term consequences of anti-cancer chemotherapy continue to be a major cause of concern. The effectiveness of current medications to prevent the negative effects of chemotherapy is frequently insufficient. As a result, the current cancer treatment pattern is shifting toward combination chemotherapy. A combination of medications improves the possibility that numerous oncogenic and resistance signalings will be inhibited simultaneously, whereas chemotherapeutics can affect cancer cells by affecting only one or two stages in the cell cycle. A modified cell line and the development of drug resistance are less likely when the malignant cells are attacked via several chemo-preventive agents. Recent research using the ovarian sarcoma M5076 cell line demonstrated that the synergism of cucurbitacin I and doxorubicin enhanced cytotoxicity and reduced the volume and weight of tumor cells. It was observed that treatment with CuI and doxorubicin decreased glutathione (GSH) levels, enhancing cytotoxicity in tumors. The phytochemical also increased DOX-induced antitumor activity [81]. In both in vitro and in vivo investigations, the combination of cucurbitacin B and curcumin proved particularly efficient against hepatocellular cancer. It encouraged apoptosis and reduced the potential for multidrug resistance in human hepatocarcinoma cells. Significant activity was observed with 2:1 ratio (cucurbitacin B:curcumin). It led to changes in tumor volume, caspase3 activation and ATP down-regulation, thereby serving as a novel, promising approach for treating human hepatoma [82]. Irinotecan and cucurbitacin have been found to have synergistic effects on the ability of colon cancer cell lines to resist proliferating, which together have increased their therapeutic benefits by activation of JAK2/STAT3, which plays a crucial role in cell survival and proliferation [83]. The synergistic effect of 23, 24-dihydrocucurbitacin B and cucurbitacin R was observed on inhibiting the expression of TNF-α, IL-6 through the NF-κB pathway in HepG2 cell line. Similar effects were observed with cucurbitacin D and docetaxel, which together effectively inhibited cancer cell growth and the cloning potential of prostate cancer stem cells. This combination has been suggested to be a novel therapeutic modality for the treatment of advanced prostate cancer [84,85]. Cucurbitacin B along with gemcitabine has been observed to induce apoptosis of MDA-MB-231 breast cancerous cells by regulating JAK/STAT3, Bcl-Xl, cyclin A and B1 [86], while with imatinib-mesylate it was responsible for inhibiting the proliferation of cells and inducing apoptosis through inhibition of MMP-2 expression [87]. Administration of cucurbitacin B and higenamine (in ratios 1:1, 1:2 and 2:1) significantly increased the cytotoxic effects on breast cancer cell lines, which also increased apoptosis and cell-cycle arrest in G2/M. This combination acts on essential proteins such as Akt farnesyl-transferase, platelet-derived growth factors, cyclin A2, CDK2, etc [88]. Cucurbitacin E with doxorubicin successfully induced apoptosis, cell-cycle arrest and autophagy [89]. Recent advances in the study of cucurbitacin IIb (CuIIb) and kinoin A (KinA) from Ibervillea sonorae (S.Watson) Greene highlight the ability of these molecules to reduce proliferation and to tempt apoptotic and cell-cycle apprehension in tumors; also, the levels of STAT3 expression were downregulated after treatment with CuIIb. These findings imply that CuIIb and KinA may be considered in future research for the creation of efficient and secure anti-cancer treatments for breast, cervical, gastric and other cancer types where STAT3 is overexpressed [90].

6. Safety Studies

As several researchers have identified the presence of toxic cucurbitacins in the roots, leaves, and fruits of some plants, such as Combretum zeyheri Sond and Cucumis anguria L. [91], further studies are highly needed to evaluate the safety issue and determine the value of the no-observed-adverse-effect-level (NOAEL), before any pharmacological applications of cucurbitacins as anticancer agents can be recommended. On the other hand, it has been claimed that safety issues of cucurbitacins may be related to their specific variants, the purity of preparations and differences in the study models [92]. For example, no toxic reactions were observed in lung cancer xenografted mice treated intraperitoneally with 1 mg/kg of cucurbitacin B [93] or cucurbitacin Q [94]. Today, it is generally accepted that the active dose and lethal dose are not the same for different types of cucurbitacins, being related to their structural peculiarities [92]. Therefore, further clinical trials on the safety and efficacy of specific variants of cucurbitacins are highly required. Table 1 and Table 2 present an outline of diverse antiproliferative actions of cucurbitacins.

7. Conclusions and Further Perspectives

As demonstrated in the present review article, diverse variants of cucurbitacins can be active against different types of malignancies. Moreover, the combination of cucurbitacins with conventional chemotherapeutic drugs might lead to synergistic anticancer effects, revealing a great promise for the application of these compounds in future clinical settings as either individual agents or drug adjuvants. However, many steps have remained to achieve this attractive goal. First, the safety of cucurbitacins must be elucidated, jointly with their metabolic conversion and possible bioactivities of various metabolites. Secondly, the proper dosage regimens also need to be elaborated. Studies related to the pharmacokinetic properties of cucurbitacins, including t1/2, Cmax, Tmax, Vd, mean residence time, etc., should be carried out singly or in synergism. Investigations on the metabolic conversions of cucurbitacins will improve its bioavailability and stability prospective. In this way, the current review presents a strong basis to move on with these next steps in the path to ultimately find novel, safe and more efficient therapies against cancer.

Author Contributions

Conceptualization, H.S.T. and A.P.K.; methodology, validation, writing—review, H.S.T., P.R., A.C., A.R., S.R. and K.S.; formal analysis, resources, D.A., M.K., K.D.; data curation, E.H.C.L., K.C.-Y.Y., S.M.C.; review, editing and finalization, A.P.K. All authors have read and agreed to the published version of the manuscript.

Funding

A.P.K. was supported by the Singapore Ministry of Education, grant number (MOE-T2EP30120-0016). E.H.C.L. is supported by a PhD Scholarship from Yong Loo Lin School of Medicine, National University of Singapore. K.C.-Y.Y. is supported by a President’s Scholarship from National University of Singapore. S.M.C. is supported by an Industry PhD Scholarship from Singapore Economic Development Board.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Acknowledgments

The authors would like to acknowledge the utility of BioRender software to draw some figures.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Sung, H.; Ferlay, J.; Siegel, R.L.; Laversanne, M.; Soerjomataram, I.; Jemal, A.; Bray, F. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J. Clin. 2021, 71, 209–249. [Google Scholar] [CrossRef] [PubMed]
  2. Devlin, E.J.; Denson, L.A.; Whitford, H.S. Cancer Treatment Side Effects: A Meta-analysis of the Relationship Between Response Expectancies and Experience. J. Pain Symptom Manag. 2017, 54, 245–258.e2. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  3. O’Reilly, M.; Mellotte, G.; Ryan, B.; O’Connor, A. Gastrointestinal side effects of cancer treatments. Ther. Adv. Chronic Dis. 2020, 11, 2040622320970354. [Google Scholar] [CrossRef] [PubMed]
  4. Kirtonia, A.; Gala, K.; Fernandes, S.G.; Pandya, G.; Pandey, A.K.; Sethi, G.; Khattar, E.; Garg, M. Repurposing of drugs: An attractive pharmacological strategy for cancer therapeutics. Semin. Cancer Biol. 2021, 68, 258–278. [Google Scholar] [CrossRef] [PubMed]
  5. Gupta, B.; Sadaria, D.; Warrier, V.U.; Kirtonia, A.; Kant, R.; Awasthi, A.; Baligar, P.; Pal, J.K.; Yuba, E.; Sethi, G.; et al. Plant lectins and their usage in preparing targeted nanovaccines for cancer immunotherapy. Semin. Cancer Biol. 2022, 80, 87–106. [Google Scholar] [CrossRef] [PubMed]
  6. Tariq, A.; Sadia, S.; Pan, K.; Ullah, I.; Mussarat, S.; Sun, F.; Abiodun, O.O.; Batbaatar, A.; Li, Z.; Song, D.; et al. A systematic review on ethnomedicines of anti-cancer plants. Phytother. Res. 2017, 31, 202–264. [Google Scholar] [CrossRef]
  7. Yang, S.F.; Weng, C.J.; Sethi, G.; Hu, D.N. Natural bioactives and phytochemicals serve in cancer treatment and prevention. Evid. Based. Complement. Alternat. Med. 2013, 2013, 698190. [Google Scholar] [CrossRef] [Green Version]
  8. Ren, B.; Kwah, M.X.Y.; Liu, C.; Ma, Z.; Shanmugam, M.K.; Ding, L.; Xiang, X.; Ho, P.C.L.; Wang, L.; Ong, P.S.; et al. Resveratrol for cancer therapy: Challenges and future perspectives. Cancer Lett. 2021, 515, 63–72. [Google Scholar] [CrossRef]
  9. Bishayee, A.; Sethi, G. Bioactive natural products in cancer prevention and therapy: Progress and promise. Semin. Cancer Biol. 2016, 40–41, 1–3. [Google Scholar] [CrossRef]
  10. Sak, K. Anticancer action of plant products: Changing stereotyped attitudes. Explor. Target. Anti-Tumor Ther. 2022, 3, 423–427. [Google Scholar] [CrossRef]
  11. Liu, C.; Ho, P.C.L.; Wong, F.C.; Sethi, G.; Wang, L.Z.; Goh, B.C. Garcinol: Current status of its anti-oxidative, anti-inflammatory and anti-cancer effects. Cancer Lett. 2015, 362, 8–14. [Google Scholar] [CrossRef] [PubMed]
  12. Dehshahri, A.; Ashrafizadeh, M.; Ghasemipour Afshar, E.; Pardakhty, A.; Mandegary, A.; Mohammadinejad, R.; Sethi, G. Topoisomerase inhibitors: Pharmacology and emerging nanoscale delivery systems. Pharmacol. Res. 2020, 151, 104551. [Google Scholar] [CrossRef] [PubMed]
  13. Yin, H.; Que, R.; Liu, C.; Ji, W.; Sun, B.; Lin, X.; Zhang, Q.; Zhao, X.; Peng, Z.; Zhang, X.; et al. Survivin-targeted drug screening platform identifies a matrine derivative WM-127 as a potential therapeutics against hepatocellular carcinoma. Cancer Lett. 2018, 425, 54–64. [Google Scholar] [CrossRef] [PubMed]
  14. Wu, D.; Wang, Z.; Lin, M.; Shang, Y.; Wang, F.; Zhou, J.Y.; Wang, F.; Zhang, X.; Luo, X.; Huang, W. In Vitro and In Vivo Antitumor Activity of Cucurbitacin C, a Novel Natural Product from Cucumber. Front. Pharmacol. 2019, 10, 1287. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  15. Chen, T.; Ma, B.; Lu, S.; Zeng, L.; Wang, H.; Shi, W.; Zhou, L.; Xia, Y.; Zhang, X.; Zhang, J.; et al. Cucumber-Derived Nanovesicles Containing Cucurbitacin B for Non-Small Cell Lung Cancer Therapy. Int. J. Nanomed. 2022, 17, 3583–3599. [Google Scholar] [CrossRef] [PubMed]
  16. Pang, L.; Zhang, L.; Zhou, H.; Cao, L.; Shao, Y.; Li, T. Reactive Oxygen Species-Responsive Nanococktail With Self-Amplificated Drug Release for Efficient Co-Delivery of Paclitaxel/Cucurbitacin B and Synergistic Treatment of Gastric Cancer. Front. Chem. 2022, 10, 844426. [Google Scholar] [CrossRef] [PubMed]
  17. Zhang, H.; Zhao, B.; Wei, H.Z.; Zeng, H.; Sheng, D.; Zhang, Y. Cucurbitacin B controls M2 macrophage polarization to suppresses metastasis via targeting JAK-2/STAT3 signalling pathway in colorectal cancer. J. Ethnopharmacol. 2022, 287, 114915. [Google Scholar] [CrossRef]
  18. Üremiş, N.; Üremiş, M.M.; Çiğremiş, Y.; Tosun, E.; Baysar, A.; Türköz, Y. Cucurbitacin I exhibits anticancer efficacy through induction of apoptosis and modulation of JAK/STAT3, MAPK/ERK, and AKT/mTOR signaling pathways in HepG2 cell line. J. Food Biochem. 2022, 46, e14333. [Google Scholar] [CrossRef]
  19. Xu, D.; Shen, H.; Tian, M.; Chen, W.; Zhang, X. Cucurbitacin I inhibits the proliferation of pancreatic cancer through the JAK2/STAT3 signalling pathway in vivo and in vitro. J. Cancer 2022, 13, 2050–2060. [Google Scholar] [CrossRef]
  20. Li, R.; Xiao, J.; Tang, S.; Lin, X.; Xu, H.; Han, B.; Yang, M.; Liu, F. Cucurbitacin I induces apoptosis in ovarian cancer cells through oxidative stress and the p190B-Rac1 signaling axis. Mol. Med. Rep. 2020, 22, 2545–2550. [Google Scholar] [CrossRef]
  21. Vidal-Gutiérrez, M.; Torres-Moreno, H.; Arenas-Luna, V.; Loredo-Mendoza, M.L.; Tejeda-Dominguez, F.; Velazquez, C.; Vilegas, W.; Hernández-Gutiérrez, S.; Robles-Zepeda, R.E. Standardized phytopreparations and cucurbitacin IIb from Ibervillea sonorae (S. Watson) greene induce apoptosis in cervical cancer cells by Nrf2 inhibition. J. Ethnopharmacol. 2022, 298, 115606. [Google Scholar] [CrossRef] [PubMed]
  22. Aiswarya, S.U.D.; Vikas, G.; Haritha, N.H.; Liju, V.B.; Shabna, A.; Swetha, M.; Rayginia, T.P.; Keerthana, C.K.; Nath, L.R.; Reshma, M.V.; et al. Cucurbitacin B, Purified and Characterized From the Rhizome of Corallocarpus epigaeus Exhibits Anti-Melanoma Potential. Front. Oncol. 2022, 12, 903832. [Google Scholar] [CrossRef] [PubMed]
  23. Díaz, M.T.B.; Font, R.; Gómez, P.; Río Celestino, M. Del Summer squash. Nutr. Compos. Antioxid. Prop. Fruits Veg. 2020, 239–254. [Google Scholar] [CrossRef]
  24. Kaushik, U.; Aeri, V.; Mir, S.R. Cucurbitacins–An insight into medicinal leads from nature. Pharmacogn. Rev. 2015, 9, 12. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  25. Jian, C.C.; Ming, H.C.; Rui, L.N.; Cordel, G.A.; Qiuz, S.X. Cucurbitacins and cucurbitane glycosides: Structures and biological activities. Nat. Prod. Rep. 2005, 22, 386–399. [Google Scholar] [CrossRef]
  26. Chan, K.T.; Meng, F.Y.; Li, Q.; Ho, C.Y.; Lam, T.S.; To, Y.; Lee, W.H.; Li, M.; Chu, K.H.; Toh, M. Cucurbitacin B induces apoptosis and S phase cell cycle arrest in BEL-7402 human hepatocellular carcinoma cells and is effective via oral administration. Cancer Lett. 2010, 294, 118–124. [Google Scholar] [CrossRef]
  27. Ding, T.; Zhang, Y.; Chen, A.; Tang, Y.; Liu, M.; Wang, X. Effects of Cucurbitacin E, a Tetracyclic Triterpene Compound from Cucurbitaceae, on the Pharmacokinetics and Pharmacodynamics of Warfarin in Rats. Basic Clin. Pharmacol. Toxicol. 2015, 116, 385–389. [Google Scholar] [CrossRef]
  28. Hunsakunachai, N.; Nuengchamnong, N.; Jiratchariyakul, W.; Kummalue, T.; Khemawoot, P. Pharmacokinetics of cucurbitacin B from Trichosanthes cucumerina L. in rats. BMC Complement. Altern. Med. 2019, 19, 157. [Google Scholar] [CrossRef] [Green Version]
  29. Tang, L.; Fu, L.; Zhu, Z.; Yang, Y.; Sun, B.; Shan, W.; Zhang, Z. Modified mixed nanomicelles with collagen peptides enhanced oral absorption of Cucurbitacin B: Preparation and evaluation. Drug Deliv. 2019, 25, 862–871. [Google Scholar] [CrossRef] [Green Version]
  30. Manu, K.A.; Shanmugam, M.K.; Li, F.; Chen, L.; Siveen, K.S.; Ahn, K.S.; Kumar, A.P.; Sethi, G. Simvastatin sensitizes human gastric cancer xenograft in nude mice to capecitabine by suppressing nuclear factor-kappa B-regulated gene products. J. Mol. Med. 2014, 92, 267–276. [Google Scholar] [CrossRef]
  31. Sethi, G.; Kwang, S.A.; Sandur, S.K.; Lin, X.; Chaturvedi, M.M.; Aggarwal, B.B. Indirubin enhances tumor necrosis factor-induced apoptosis through modulation of nuclear factor-kappa B signaling pathway. J. Biol. Chem. 2006, 281, 23425–23435. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  32. Jung, Y.Y.; Um, J.Y.; Chinnathambi, A.; Govindasamy, C.; Sethi, G.; Ahn, K.S. Leelamine Modulates STAT5 Pathway Causing Both Autophagy and Apoptosis in Chronic Myelogenous Leukemia Cells. Biology 2022, 11, 366. [Google Scholar] [CrossRef] [PubMed]
  33. Chopra, P.; Sethi, G.; Dastidar, S.G.; Ray, A. Polo-like kinase inhibitors: An emerging opportunity for cancer therapeutics. Expert Opin. Investig. Drugs 2010, 19, 27–43. [Google Scholar] [CrossRef] [PubMed]
  34. Xiao, W.; Li, J.; Hu, J.; Wang, L.; Huang, J.R.; Sethi, G.; Ma, Z. Circular RNAs in cell cycle regulation: Mechanisms to clinical significance. Cell Prolif. 2021, 54, 13143. [Google Scholar] [CrossRef] [PubMed]
  35. Raghunath, A.; Sundarraj, K.; Arfuso, F.; Sethi, G.; Perumal, E. Dysregulation of Nrf2 in Hepatocellular Carcinoma: Role in Cancer Progression and Chemoresistance. Cancers 2018, 10, 481. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  36. Ma, Z.; Xiang, X.; Li, S.; Xie, P.; Gong, Q.; Goh, B.C.; Wang, L. Targeting hypoxia-inducible factor-1, for cancer treatment: Recent advances in developing small-molecule inhibitors from natural compounds. Semin. Cancer Biol. 2022, 80, 379–390. [Google Scholar] [CrossRef] [PubMed]
  37. Rajendran, P.; Ong, T.H.; Chen, L.; Li, F.; Shanmugam, M.K.; Vali, S.; Abbasi, T.; Kapoor, S.; Sharma, A.; Kumar, A.P.; et al. Suppression of signal transducer and activator of transcription 3 activation by butein inhibits growth of human hepatocellular carcinoma in vivo. Clin. Cancer Res. 2011, 17, 1425–1439. [Google Scholar] [CrossRef] [Green Version]
  38. Ahn, K.S.; Sethi, G.; Aggarwal, B.B. Simvastatin potentiates TNF-alpha-induced apoptosis through the down-regulation of NF-kappaB-dependent antiapoptotic gene products: Role of IkappaBalpha kinase and TGF-beta-activated kinase-1. J. Immunol. 2007, 178, 2507–2516. [Google Scholar] [CrossRef] [Green Version]
  39. Mohan, C.D.; Rangappa, S.; Nayak, S.C.; Jadimurthy, R.; Wang, L.; Sethi, G.; Garg, M.; Rangappa, K.S. Bacteria as a treasure house of secondary metabolites with anticancer potential. Semin. Cancer Biol. 2021, 86, 998–1013. [Google Scholar] [CrossRef]
  40. Li, H.; Chen, H.; Li, R.; Xin, J.; Wu, S.; Lan, J.; Xue, K.; Li, X.; Zuo, C.; Jiang, W.; et al. Cucurbitacin I induces cancer cell death through the endoplasmic reticulum stress pathway. J. Cell. Biochem. 2018, 120, 2391–2403. [Google Scholar] [CrossRef]
  41. Mao, D.; Liu, A.H.; Wang, Z.P.; Zhang, X.W.; Lu, H. Cucurbitacin B inhibits cell proliferation and induces cell apoptosis in colorectal cancer by modulating methylation status of BTG3. Neoplasma 2019, 66, 593–602. [Google Scholar] [CrossRef] [PubMed]
  42. Kong, Y.; Chen, J.; Zhou, Z.; Xia, H.; Qiu, M.H.; Chen, C. Cucurbitacin E induces cell cycle G2/M phase arrest and apoptosis in triple negative breast cancer. PLoS ONE 2014, 9, e103760. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  43. Kim, M.S.; Lee, K.; Ku, J.M.; Choi, Y.J.; Mok, K.; Kim, D.; Cheon, C.; Ko, S.G. Cucurbitacin D Induces G2/M Phase Arrest and Apoptosis via the ROS/p38 Pathway in Capan-1 Pancreatic Cancer Cell Line. Evid. Based. Complement. Alternat. Med. 2020, 2020, 6571674. [Google Scholar] [CrossRef] [PubMed]
  44. Duangmano, S.; Sae-Lim, P.; Suksamrarn, A.; Patmasiriwat, P.; Domann, F.E. Cucurbitacin B Causes Increased Radiation Sensitivity of Human Breast Cancer Cells via G2/M Cell Cycle Arrest. J. Oncol. 2012, 2012, 601682. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  45. Huang, W.W.; Yang, J.S.; Lin, M.W.; Chen, P.Y.; Chiou, S.M.; Chueh, F.S.; Lan, Y.H.; Pai, S.J.; Tsuzuki, M.; Ho, W.J.; et al. Cucurbitacin E Induces G(2)/M Phase Arrest through STAT3/p53/p21 Signaling and Provokes Apoptosis via Fas/CD95 and Mitochondria-Dependent Pathways in Human Bladder Cancer T24 Cells. Evid. Based. Complement. Alternat. Med. 2012, 2012, 952762. [Google Scholar] [CrossRef] [Green Version]
  46. Liu, T.; Zhang, M.; Zhang, H.; Sun, C.; Deng, Y. Inhibitory effects of cucurbitacin B on laryngeal squamous cell carcinoma. Eur. Arch. Otorhinolaryngol. 2008, 265, 1225–1232. [Google Scholar] [CrossRef] [PubMed]
  47. Blaskovich, M.A.; Sun, J.; Cantor, A.; Turkson, J.; Jove, R.; Sebti, S.M. Discovery of JSI-124 (cucurbitacin I), a selective Janus kinase/signal transducer and activator of transcription 3 signaling pathway inhibitor with potent antitumor activity against human and murine cancer cells in mice-PubMed. Cancer Res. 2003, 63, 1270–1279. [Google Scholar] [PubMed]
  48. Liang, J.; Chen, D. Advances in research on the anticancer mechanism of the natural compound cucurbitacin from Cucurbitaceae plants: A review. Tradit. Chin. Med. 2019, 4, 68. [Google Scholar] [CrossRef]
  49. Dong, Y.; Lu, B.; Zhang, X.; Zhang, J.; Lai, L.; Li, D.; Wu, Y.; Song, Y.; Luo, J.; Pang, X.; et al. Cucurbitacin E, a tetracyclic triterpenes compound from Chinese medicine, inhibits tumor angiogenesis through VEGFR2-mediated Jak2-STAT3 signaling pathway. Carcinogenesis 2010, 31, 2097–2104. [Google Scholar] [CrossRef] [Green Version]
  50. Torres-Moreno, H.; Marcotullio, M.C.; Velázquez, C.; Ianni, F.; Garibay-Escobar, A.; Robles-Zepeda, R.E. Cucurbitacin IIb, a steroidal triterpene from Ibervillea sonorae induces antiproliferative and apoptotic effects on cervical and lung cancer cells. Steroids 2020, 157, 108597. [Google Scholar] [CrossRef] [PubMed]
  51. Liang, Y.; Zhang, T.; Ren, L.; Jing, S.; Li, Z.; Zuo, P.; Li, T.; Wang, Y.; Zhang, J.; Wei, Z. Cucurbitacin IIb induces apoptosis and cell cycle arrest through regulating EGFR/MAPK pathway. Environ. Toxicol. Pharmacol. 2021, 81, 103542. [Google Scholar] [CrossRef] [PubMed]
  52. Lin, X.; Farooqi, A.A. Cucurbitacin mediated regulation of deregulated oncogenic signaling cascades and non-coding RNAs in different cancers: Spotlight on JAK/STAT, Wnt/β-catenin, mTOR, TRAIL-mediated pathways. Semin. Cancer Biol. 2021, 73, 302–309. [Google Scholar] [CrossRef] [PubMed]
  53. Liu, J.H.; Li, C.; Cao, L.; Zhang, C.H.; Zhang, Z.H. Cucurbitacin B regulates lung cancer cell proliferation and apoptosis via inhibiting the IL-6/STAT3 pathway through the lncRNA XIST/miR-let-7c axis. Pharm. Biol. 2022, 60, 154–162. [Google Scholar] [CrossRef] [PubMed]
  54. Siveen, K.S.; Ahn, K.S.; Ong, T.H.; Shanmugam, M.K.; Li, F.; Yap, W.N.; Kumar, A.P.; Fong, C.W.; Tergaonkar, V.; Hui, K.M.; et al. Y-tocotrienol inhibits angiogenesis-dependent growth of human hepatocellular carcinoma through abrogation of AKT/mTOR pathway in an orthotopic mouse model. Oncotarget 2014, 5, 1897–1911. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  55. Wu, Q.; You, L.; Nepovimova, E.; Heger, Z.; Wu, W.; Kuca, K.; Adam, V. Hypoxia-inducible factors: Master regulators of hypoxic tumor immune escape. J. Hematol. Oncol. 2022, 15, 77. [Google Scholar] [CrossRef] [PubMed]
  56. Piao, X.M.; Gao, F.; Zhu, J.X.; Wang, L.J.; Zhao, X.; Li, X.; Sheng, M.M.; Zhang, Y. Cucurbitacin B inhibits tumor angiogenesis by triggering the mitochondrial signaling pathway in endothelial cells. Int. J. Mol. Med. 2018, 42, 1018–1025. [Google Scholar] [CrossRef] [Green Version]
  57. Sheikh, I.; Sharma, V.; Tuli, H.S.; Aggarwal, D.; Sankhyan, A.; Vyas, P.; Sharma, A.K.; Bishayee, A. Cancer Chemoprevention by Flavonoids, Dietary Polyphenols and Terpenoids. Biointerface Res. Appl. Chem. 2021, 11, 8502–8537. [Google Scholar] [CrossRef]
  58. Yin, B.; Fang, D.M.; Zhou, X.L.; Gao, F. Natural products as important tyrosine kinase inhibitors. Eur. J. Med. Chem. 2019, 182, 111664. [Google Scholar] [CrossRef]
  59. Sinha, S.; Khan, S.; Shukla, S.; Lakra, A.D.; Kumar, S.; Das, G.; Maurya, R.; Meeran, S.M. Cucurbitacin B inhibits breast cancer metastasis and angiogenesis through VEGF-mediated suppression of FAK/MMP-9 signaling axis. Int. J. Biochem. Cell Biol. 2016, 77, 41–56. [Google Scholar] [CrossRef]
  60. Garg, S.; Kaul, S.C.; Wadhwa, R. Cucurbitacin B and cancer intervention: Chemistry, biology and mechanisms (review). Int. J. Oncol. 2018, 52, 19–37. [Google Scholar] [CrossRef]
  61. Liu, Y.; Yang, H.; Guo, Q.; Liu, T.; Jiang, Y.; Zhao, M.; Zeng, K.; Tu, P. Cucurbitacin E Inhibits Huh7 Hepatoma Carcinoma Cell Proliferation and Metastasis via Suppressing MAPKs and JAK/STAT3 Pathways. Molecules 2020, 25, 560. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  62. Ramezani, M.; Hasani, M.; Ramezani, F.; Abdolmaleki, M.K. Cucurbitacins: A focus on Cucurbitacin E as a natural product and their biological activities. Pharm. Sci. 2020, 27, 1–13. [Google Scholar] [CrossRef]
  63. Yun, W.; Dan, W.; Liu, J.; Guo, X.; Li, M.; He, Q. Investigation of the Mechanism of Traditional Chinese Medicines in Angiogenesis through Network Pharmacology and Data Mining. Evid.-Based Complement. Altern. Med. 2021, 2021, 5539970. [Google Scholar] [CrossRef] [PubMed]
  64. Ren, Y.; Kinghorn, A.D. Natural Product Triterpenoids and Their Semi-Synthetic Derivatives with Potential Anticancer Activity. Planta Med. 2019, 85, 802–814. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  65. Sathya, T.N.; Mehta, V.A.; Senthil, D.; Navaneethakrishnan, K.; Murugan, S.; Kumaravel, T. Cytotoxicity evaluation of CELNORM, a nutritional health supplement, on MCF7 breast cancer cells. Indian J. Sci. Technol. 2020, 13, 3070–3075. [Google Scholar] [CrossRef]
  66. Ong, P.S.; Wang, L.Z.; Dai, X.; Tseng, S.H.; Loo, S.J.; Sethi, G. Judicious Toggling of mTOR Activity to Combat Insulin Resistance and Cancer: Current Evidence and Perspectives. Front. Pharmacol. 2016, 7, 395. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  67. Ma, Z.; Wang, Y.Y.; Xin, H.W.; Wang, L.; Arfuso, F.; Dharmarajan, A.; Kumar, A.P.; Wang, H.; Tang, F.R.; Warrier, S.; et al. The expanding roles of long non-coding RNAs in the regulation of cancer stem cells. Int. J. Biochem. Cell Biol. 2019, 108, 17–20. [Google Scholar] [CrossRef]
  68. Ashrafizadeh, M.; Zarrabi, A.; Mostafavi, E.; Aref, A.R.; Sethi, G.; Wang, L.; Tergaonkar, V. Non-coding RNA-based regulation of inflammation. Semin. Immunol. 2022, 59, 101606. [Google Scholar] [CrossRef] [PubMed]
  69. Morgan, D.; Garg, M.; Tergaonkar, V.; Tan, S.Y.; Sethi, G. Pharmacological significance of the non-canonical NF-κB pathway in tumorigenesis. Biochim. Biophys. Acta Rev. Cancer 2020, 1874, 188449. [Google Scholar] [CrossRef]
  70. Cheng, J.T.; Wang, L.; Wang, H.; Tang, F.R.; Cai, W.Q.; Sethi, G.; Xin, H.W.; Ma, Z. Insights into Biological Role of LncRNAs in Epithelial-Mesenchymal Transition. Cells 2019, 8, 1178. [Google Scholar] [CrossRef]
  71. Cai, W.; Chen, Z.X.; Rane, G.; Singh, S.S.; Choo, Z.; Wang, C.; Yuan, Y.; Tan, T.Z.; Arfuso, F.; Yap, C.T.; et al. Wanted DEAD/H or Alive: Helicases Winding Up in Cancers. J. Natl. Cancer Inst. 2017, 109, djw278. [Google Scholar] [CrossRef] [PubMed]
  72. Ong, S.K.L.; Shanmugam, M.K.; Fan, L.; Fraser, S.E.; Arfuso, F.; Ahn, K.S.; Sethi, G.; Bishayee, A. Focus on Formononetin: Anticancer Potential and Molecular Targets. Cancers 2019, 11, 611. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  73. Kapoor, N.; Ghorai, S.M.; Kushwaha, P.K.; Shukla, R.; Aggarwal, C.; Bandichhor, R. Plausible mechanisms explaining the role of cucurbitacins as potential therapeutic drugs against coronavirus 2019. Inform. Med. Unlocked 2020, 21, 100484. [Google Scholar] [CrossRef] [PubMed]
  74. Xie, H.; Tuo, X.; Zhang, F.; Bowen, L.; Zhao, W.; Xu, Y. Dietary cucurbitacin E reduces high-strength altitude training induced oxidative stress, inflammation and immunosuppression. An. Acad. Bras. Cienc. 2020, 92, 1–14. [Google Scholar] [CrossRef] [PubMed]
  75. Hua, S.; Liu, X.; Lv, S.; Wang, Z. Protective Effects of Cucurbitacin B on Acute Lung Injury Induced by Sepsis in Rats. Med. Sci. Monit. 2017, 23, 1355. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  76. Yang, L.; Ao, Q.; Zhong, Q.; Li, W.; Li, W. SIRT1/IGFBPrP1/TGF β1 axis involved in cucurbitacin B ameliorating concanavalin A-induced mice liver fibrosis. Basic Clin. Pharmacol. Toxicol. 2020, 127, 371–379. [Google Scholar] [CrossRef]
  77. Kim, S.Y.; Park, M.J.; Kwon, J.E.; Jung, K.A.; Jhun, J.Y.; Lee, S.Y.; Seo, H.B.; Ryu, J.Y.; Beak, J.A.; Choi, J.Y.; et al. Cucurbitacin E ameliorates acute graft-versus-host disease by modulating Th17 cell subsets and inhibiting STAT3 activation. Immunol. Lett. 2018, 203, 62–69. [Google Scholar] [CrossRef]
  78. Shang, J.; Liu, W.; Yin, C.; Chu, H.; Zhang, M. Cucurbitacin E ameliorates lipopolysaccharide-evoked injury, inflammation and MUC5AC expression in bronchial epithelial cells by restraining the HMGB1-TLR4-NF-κB signaling. Mol. Immunol. 2019, 114, 571–577. [Google Scholar] [CrossRef]
  79. Yuan, R.; Zhao, W.; Wang, Q.Q.; He, J.; Han, S.; Gao, H.; Feng, Y.; Yang, S. Cucurbitacin B inhibits non-small cell lung cancer in vivo and in vitro by triggering TLR4/NLRP3/GSDMD-dependent pyroptosis. Pharmacol. Res. 2021, 170, 105748. [Google Scholar] [CrossRef]
  80. Wang, X.; Bai, Y.; Yan, X.; Li, J.; Lin, B.; Dai, L.; Xu, C.; Li, H.; Li, D.; Yang, T.; et al. Cucurbitacin B exhibits antitumor effects on CD133+ HepG2 liver cancer stem cells by inhibiting JAK2/STAT3 signaling pathway. Anticancer. Drugs 2021, 32, 548–557. [Google Scholar] [CrossRef]
  81. Sadzuka, Y.; Fujiki, S.; Itai, S. Enhancement of doxorubicin-induced antitumor activity and reduction of adverse reactions by cucurbitacin I. Food Res. Int. 2012, 47, 64–69. [Google Scholar] [CrossRef]
  82. Sun, Y.; Zhang, J.; Zhou, J.; Huang, Z.; Hu, H.; Qiao, M.; Zhao, X.; Chen, D. Synergistic effect of cucurbitacin B in combination with curcumin via enhancing apoptosis induction and reversing multidrug resistance in human hepatoma cells. Eur. J. Pharmacol. 2015, 768, 28–40. [Google Scholar] [CrossRef] [PubMed]
  83. Eyol, E.; Tanrıverdi, Z.; Karakuş, F.; Yılmaz, K.; Ünüvar, S. Synergistic Anti-proliferative Effects of Cucurbitacin I and Irinotecan on Human Colorectal Cancer Cell Lines. J. Clin. Exp. Pharmacol. 2016, 6, 1000219. [Google Scholar] [CrossRef]
  84. Sikander, M.; Malik, S.; Hafeez, B.B.; Mandil, H.; Halaweish, F.T.; Jaggi, M.; Chauhan, S.C. Cucurbitacin D enhances the therapeutic efficacy of docetaxel via targeting cancer stem cells and miR-145. Cancer Res. 2018, 78, 2934. [Google Scholar] [CrossRef]
  85. Arjaibi, H.M.; Ahmed, M.S.; Halaweish, F.T. Mechanistic investigation of hepato-protective potential for cucurbitacins. Med. Chem. Res. 2017, 26, 1567–1573. [Google Scholar] [CrossRef]
  86. Aribi, A.; Gery, S.; Lee, D.H.; Thoennissen, N.H.; Thoennissen, G.B.; Alvarez, R.; Ho, Q.; Lee, K.; Doan, N.B.; Chan, K.T.; et al. The triterpenoid cucurbitacin B augments the antiproliferative activity of chemotherapy in human breast cancer. Int. J. Cancer 2013, 132, 2730–2737. [Google Scholar] [CrossRef] [Green Version]
  87. Bakar, F. Cucurbitacin B Enhances the Anticancer Effect of Imatinib Mesylate Through Inhibition of MMP-2 Expression in MCF-7 and SW480 Tumor Cell Lines. Anti-Cancer Agents Med. Chem. 2016, 8, 747–754. [Google Scholar] [CrossRef]
  88. Jin, Z.Q.; Hao, J.; Yang, X.; He, J.H.; Liang, J.; Yuan, J.W.; Mao, Y.; Liu, D.; Cao, R.; Wu, X.Z.; et al. Higenamine enhances the antitumor effects of cucurbitacin B in breast cancer by inhibiting the interaction of AKT and CDK2. Oncol. Rep. 2018, 40, 2127–2136. [Google Scholar] [CrossRef] [Green Version]
  89. Jing, S.; Zou, H.; Wu, Z.; Ren, L.; Zhang, T.; Zhang, J.; Wei, Z. Cucurbitacins: Bioactivities and synergistic effect with small-molecule drugs. J. Funct. Foods 2020, 72, 104042. [Google Scholar] [CrossRef]
  90. Torres-Moreno, H.; Valenzuela-Chavira, I.; Marcotullio, M.C.; Vidal Gutiérrez, M.; Arrellín-Rosas, G.; Angulo-Molina, A.; Hernández Gutiérrez, S.; Robles Zepeda, R.E. In Silico Prediction Model of STAT3 Inhibition and in Vivo Antitumor Activity of Cucurbitacin IIb and Kinoin a from Ibervillea Sonorae. SSRN Electron. J. 2022, 1–42. [Google Scholar] [CrossRef]
  91. Omokhua-Uyi, A.G.; Van Staden, J. Phytomedicinal relevance of South African Cucurbitaceae species and their safety assessment: A review. J. Ethnopharmacol. 2020, 259, 112967. [Google Scholar] [CrossRef] [PubMed]
  92. Liu, M.; Yan, Q.; Peng, B.; Cai, Y.; Zeng, S.; Xu, Z.; Yan, Y.; Gong, Z. Use of cucurbitacins for lung cancer research and therapy. Cancer Chemother. Pharmacol. 2021, 88, 1–14. [Google Scholar] [CrossRef] [PubMed]
  93. Kausar, H.; Munagala, R.; Bansal, S.S.; Aqil, F.; Vadhanam, M.V.; Gupta, R.C. Cucurbitacin B potently suppresses non-small-cell lung cancer growth: Identification of intracellular thiols as critical targets. Cancer Lett. 2013, 332, 35–45. [Google Scholar] [CrossRef] [PubMed]
  94. Sun, J.; Blaskovich, M.A.; Jove, R.; Livingston, S.K.; Coppola, D.; Sebti, S.M. Cucurbitacin Q: A selective STAT3 activation inhibitor with potent antitumor activity. Oncogene 2005, 24, 3236–3245. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  95. Zheng, Q.; Liu, Y.; Liu, W.; Ma, F.; Zhou, Y.I.; Chen, M.; Chang, J.; Wang, Y.; Yang, G.; He, G. Cucurbitacin B inhibits growth and induces apoptosis through the JAK2/STAT3 and MAPK pathways in SH-SY5Y human neuroblastoma cells. Mol. Med. Rep. 2014, 10, 89–94. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  96. Zhang, Z.R.; Gao, M.X.; Yang, K. Cucurbitacin B inhibits cell proliferation and induces apoptosis in human osteosarcoma cells via modulation of the JAK2/STAT3 and MAPK pathways. Exp. Ther. Med. 2017, 14, 805–812. [Google Scholar] [CrossRef] [Green Version]
  97. Kaewmeesri, P.; Kukongviriyapan, V.; Prawan, A.; Kongpetch, S.; Senggunprai, L. Cucurbitacin B Diminishes Metastatic Behavior of Cholangiocarcinoma Cells by Suppressing Focal Adhesion Kinase. Asian Pac. J. Cancer Prev. 2021, 22, 219–225. [Google Scholar] [CrossRef]
  98. Tao, B.; Wang, D.; Yang, S.; Liu, Y.; Wu, H.; Li, Z.; Chang, L.; Yang, Z.; Liu, W. Cucurbitacin B Inhibits Cell Proliferation by Regulating X-Inactive Specific Transcript Expression in Tongue Cancer. Front. Oncol. 2021, 11, 651648. [Google Scholar] [CrossRef]
  99. Liu, T.; Peng, H.; Zhang, M.; Deng, Y.; Wu, Z. Cucurbitacin B, a small molecule inhibitor of the Stat3 signaling pathway, enhances the chemosensitivity of laryngeal squamous cell carcinoma cells to cisplatin. Eur. J. Pharmacol. 2010, 641, 15–22. [Google Scholar] [CrossRef]
  100. Liu, T.; Zhang, M.; Zhang, H.; Sun, C.; Yang, X.; Deng, Y.; Ji, W. Combined antitumor activity of cucurbitacin B and docetaxel in laryngeal cancer. Eur. J. Pharmacol. 2008, 587, 78–84. [Google Scholar] [CrossRef]
  101. LUO, W.W.; ZHAO, W.W.; LU, J.J.; WANG, Y.T.; CHEN, X.P. Cucurbitacin B suppresses metastasis mediated by reactive oxygen species (ROS) via focal adhesion kinase (FAK) in breast cancer MDA-MB-231 cells. Chin. J. Nat. Med. 2018, 16, 10–19. [Google Scholar] [CrossRef] [PubMed]
  102. Ren, G.; Sha, T.; Guo, J.; Li, W.; Lu, J.; Chen, X. Cucurbitacin B induces DNA damage and autophagy mediated by reactive oxygen species (ROS) in MCF-7 breast cancer cells. J. Nat. Med. 2015, 69, 522–530. [Google Scholar] [CrossRef] [PubMed]
  103. Guo, J.; Wu, G.; Bao, J.; Hao, W.; Lu, J.; Chen, X. Cucurbitacin B induced ATM-mediated DNA damage causes G2/M cell cycle arrest in a ROS-dependent manner. PLoS ONE 2014, 9, e88140. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  104. Sikander, M.; Malik, S.; Khan, S.; Kumari, S.; Chauhan, N.; Khan, P.; Halaweish, F.T.; Chauhan, B.; Yallapu, M.M.; Jaggi, M.; et al. Novel Mechanistic Insight into the Anticancer Activity of Cucurbitacin D against Pancreatic Cancer (Cuc D Attenuates Pancreatic Cancer). Cells 2019, 9, 103. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  105. Yuan, R.; Fan, Q.; Liang, X.; Han, S.; He, J.; Wang, Q.Q.; Gao, H.; Feng, Y.; Yang, S. Cucurbitacin B inhibits TGF-β1-induced epithelial-mesenchymal transition (EMT) in NSCLC through regulating ROS and PI3K/Akt/mTOR pathways. Chin. Med. 2022, 17, 24. [Google Scholar] [CrossRef] [PubMed]
  106. Baodan, Y.U.; Zheng, L.; Tang, H.; Wang, W.; Yongping, L.I.N. Cucurbitacin B enhances apoptosis in gefitinib resistant non-small cell lung cancer by modulating the miR-17-5p/STAT3 axis. Mol. Med. Rep. 2021, 240, 12349. [Google Scholar] [CrossRef]
  107. Liu, P.; Xiang, Y.; Liu, X.; Zhang, T.; Yang, R.; Chen, S.; Xu, L.; Yu, Q.; Zhao, H.; Zhang, L.; et al. Cucurbitacin B Induces the Lysosomal Degradation of EGFR and Suppresses the CIP2A/PP2A/Akt Signaling Axis in Gefitinib-Resistant Non-Small Cell Lung Cancer. Molecules 2019, 24, 647. [Google Scholar] [CrossRef] [Green Version]
  108. Zhu, X.; Huang, H.; Zhang, J.; Liu, H.; Ao, R.; Xiao, M.; Wu, Y. The anticancer effects of Cucurbitacin I inhibited cell growth of human non-small cell lung cancer through PI3K/AKT/p70S6K pathway. Mol. Med. Rep. 2018, 17, 2750–2756. [Google Scholar] [CrossRef] [Green Version]
  109. Ni, Y.; Wu, S.; Wang, X.; Zhu, G.; Chen, X.; Ding, Y.; Jiang, W. Cucurbitacin I induces pro-death autophagy in A549 cells via the ERK-mTOR-STAT3 signaling pathway. J. Cell. Biochem. 2018, 119, 6104–6112. [Google Scholar] [CrossRef]
  110. Wang, W.D.; Liu, Y.; Su, Y.; Xiong, X.Z.; Shang, D.; Xu, J.J.; Liu, H.J. Antitumor And Apoptotic Effects Of Cucurbitacin A In A-549 Lung Carcinoma Cells Is Mediated Via G2/M Cell Cycle Arrest And M-Tor/Pi3k/Akt Signalling Pathway. Afr. J. Tradit. Complement. Altern. Med. AJTCAM 2017, 14, 75–82. [Google Scholar] [CrossRef]
  111. Zhang, M.; Bian, Z.G.; Zhang, Y.; Wang, J.H.; Kan, L.; Wang, X.; Niu, H.Y.; He, P. Cucurbitacin B inhibits proliferation and induces apoptosis via STAT3 pathway inhibition in A549 lung cancer cells. Mol. Med. Rep. 2014, 10, 2905–2911. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  112. Hsu, H.S.; Huang, P.I.; Chang, Y.L.; Tzao, C.; Chen, Y.W.; Shih, H.C.; Hung, S.C.; Chen, Y.C.; Tseng, L.M.; Chiou, S.H. Cucurbitacin I inhibits tumorigenic ability and enhances radiochemosensitivity in nonsmall cell lung cancer-derived CD133-positive cells. Cancer 2011, 117, 2970–2985. [Google Scholar] [CrossRef] [PubMed]
  113. Liu, X.; Duan, C.; Ji, J.; Zhang, T.; Yuan, X.; Zhang, Y.; Ma, W.; Yang, J.; Yang, L.; Jiang, Z.; et al. Cucurbitacin B induces autophagy and apoptosis by suppressing CIP2A/PP2A/mTORC1 signaling axis in human cisplatin resistant gastric cancer cells. Oncol. Rep. 2017, 38, 271–278. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  114. Xie, Y.L.; Tao, W.H.; Yang, T.X.; Qiao, J.G. Anticancer effect of cucurbitacin B on MKN-45 cells via inhibition of the JAK2/STAT3 signaling pathway. Exp. Ther. Med. 2016, 12, 2709–2715. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  115. Chai, Y.; Xiang, K.; Wu, Y.; Zhang, T.; Liu, Y.; Liu, X.; Zhen, W.; Si, Y. Cucurbitacin B Inhibits the Hippo-YAP Signaling Pathway and Exerts Anticancer Activity in Colorectal Cancer Cells. Med. Sci. Monit. 2018, 24, 9251–9258. [Google Scholar] [CrossRef] [PubMed]
  116. Kurman, Y.; Kiliccioglu, I.; Dikmen, A.U.; Esendagli, G.; Bilen, C.Y.; Sozen, S.; Konac, E. Cucurbitacin B and cisplatin induce the cell death pathways in MB49 mouse bladder cancer model. Exp. Biol. Med. 2020, 245, 805–814. [Google Scholar] [CrossRef] [PubMed]
  117. Liu, J.; Liu, X.; Ma, W.; Kou, W.; Li, C.; Zhao, J. Anticancer activity of cucurbitacin-A in ovarian cancer cell line SKOV3 involves cell cycle arrest, apoptosis and inhibition of mTOR/PI3K/Akt signaling pathway-PubMed. J. Buon. 2018, 23, 124–128. [Google Scholar]
Figure 1. Basic skeleton of cucurbitacins. (A) (8R,9R,10S,13R,14R,17R)-4,4,8,9,10,13,14,17-octamethyl-17-((R)-6-methylheptan-2-yl)-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthrene (Cucurbitacin). (B) (8S,9R,10R, 13R,14S, 16R, 17R)-17-((R,E)-2,6-dihydroxy-6-methyl-3-oxohept-4-en-2-yl)-2,16-dihydroxy-4,4,9,13,14-pentamethyl-7,8,9,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthrene-3,11(4H)-dione (Cucurbitacin I).
Figure 1. Basic skeleton of cucurbitacins. (A) (8R,9R,10S,13R,14R,17R)-4,4,8,9,10,13,14,17-octamethyl-17-((R)-6-methylheptan-2-yl)-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthrene (Cucurbitacin). (B) (8S,9R,10R, 13R,14S, 16R, 17R)-17-((R,E)-2,6-dihydroxy-6-methyl-3-oxohept-4-en-2-yl)-2,16-dihydroxy-4,4,9,13,14-pentamethyl-7,8,9,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthrene-3,11(4H)-dione (Cucurbitacin I).
Biomolecules 13 00057 g001
Figure 2. Molecular targets of cucurbitacins in modulating cell-cycle progression and inducing apoptotic cell death.
Figure 2. Molecular targets of cucurbitacins in modulating cell-cycle progression and inducing apoptotic cell death.
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Figure 3. Molecular targets of cucurbitacins in suppressing angiogenesis and impeding cancer cell metastasis.
Figure 3. Molecular targets of cucurbitacins in suppressing angiogenesis and impeding cancer cell metastasis.
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Figure 4. Anti-inflammatory targets of cucurbitacins in malignant cells.
Figure 4. Anti-inflammatory targets of cucurbitacins in malignant cells.
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Table 1. Antiproliferative actions of cucurbitacins using in vitro investigations.
Table 1. Antiproliferative actions of cucurbitacins using in vitro investigations.
Type of TumorCell LinesEffectsMechanismsConcentrationReferences
NeuroblastomaSH-SY5YRegulation of cell cycle and induces apoptosis↑ cell-cycle arrest at the G2/M phase, ↓ p-JAK2, ↓ p-STAT3, ↓ phospho-extracellular signal-regulated kinases, ↓ c-Jun N-terminal kinase, ↓ p38, ↓ MAPK, ↓ Cyclin B1 ↓ Bcl2- x, ↑ p53 and p21, ↓ Bcl-2 ↑ Bax0–128 µM[95]
OsteosarcomaU-2 OSCell-cycle apprehension, apoptosis and inhibition of angiogenesis↓ cell viability, proliferation, migration ability, ↓ MMP-2 and 9, ↑ apoptotic pathway, ↓ MAPK signaling andJAK2/STAT3 cascade, ↓ VEG F, ↑ caspase-3, -8 and -9, ↑ Bad and Bax, ↓ Bcl-2 and Bcl-xL, ↓ p38, ERK1/2, JNK and p-JNK20, 40, 80 and 100 µM[96]
CholangiocarcinomaKKU-452Inhibits metastatic behavior↓ FAK activation, ↓ phospho-FAK protein, ↓ migration, invasion and adhesion abilities, ↓ MMP-9, ICAM-1 and VEGF,0, 5, 10, 25, 50, 100 nM[97]
Tongue squamousCAL27 and SCC9Induced apoptosis and microRNA mediated↓ proliferation, migration and invasion, ↓ Xinactive specific transcript (XIST), ↑ miR-29b0.001, 0.01, 0.1, 1, 10, 100 µM[98]
Laryngeal squamousHep-2Regulation of cell cycle and apoptosiscompared with single treatment,
combination treatment ↓ cell proliferation and viability, G2/M enrichment was accompanied by a reduction in G0/G1 phase cells, ↑ condensation of chromatin, ↑ nuclear fragmentations and apoptotic bodies, ↓ p-STAT3, ↓ Bcl-2, ↓ cyclin B1
1 µM cucurbitacin B + 2, 5, 10, 20, and 30 µM cisplatin[99]
Hep-2Regulation of cell cycle, apoptosis, enhance docetaxel chemosensitivitycompared with single treatment,
combination treatment ↓ cell proliferation and viability, G2/M enrichment was accompanied by a reduction in G0/G1 phase cells, ↑ condensation of chromatin, ↑ nuclear fragmentations and apoptotic bodies, significant activation (phosphorylation) of ERK1/2, ↓ p-STAT3, ↓ Bcl-2, ↓ cyclin B1
1 µM cucurbitacin B + 25 nM docetaxel[100]
ColonHCT116;Apoptosis induction↓ proliferation and migration ability, G2/M arrest, ↓ cyclin A, ↓ cyclin D1, ↑ p21, ↑ early apoptosis, ↓ p- Akt (Ser473)0.001 μM–10 μM[14]
BreastMDA-MB-231Suppresses metastasis↓ migration, invasion and adhesion ability, ↓ p-FAK (focal adhesion kinase), ↓ p- paxillin, ↑ intracellular ROS generation,0–100 nmol·L−1[101]
MCF-7Induces autophagy↓ cell viability, ↑ γH2AX, comet tails were significantly longer, ↑ phosphorylation of ATM (Ser-1981) and ATR (Ser428, ↑ LC3 II, ↓ p-mTOR, ↓ p-Akt (Ser308 and Ser473), ↓ p62, ↑ Beclin-1 and p-ULK1 (Ser 317), ↑ intracellular ROS0–200 nM[102]
MCF-7Regulation of cell cycle and induces apoptosis↑ γH2AX, comet tails were significantly longer, ↑ phosphorylation of ATM (Ser-1981) ↑ p- p53(Ser-15)0–800 nM[103]
PancreaticASPC-1,BXPC-3, CFPAC-1, SW 1990Induced cell-cycle Arrest and apoptosis↓ proliferation, viability, ↑ percentage of cells in G2/M phase ↓ decrease in S and G0/G phase cells, ↓ cyclin B1, ↓ cyclin D1 and cyclin A2, ↓ Caspase3 and PARP1, ↓ p-JAK2 andp-STAT30, 0.25, 0.5 and 1.0 μM[19]
AsPC-1, BxPC-3, CaPan-1, and HPAF-IICell-cycle arrest↓ viability of PanCa cells, ↓ colony formation capacity, ↑ G2/M Phase, ↓ invasion and migration ability, ↓ MUC13, restores miR-145 expression, ↓ proliferation of gemcitabine resistant PanCa cells, ↓ RRM1/2 expression,0.1, 0.25, and 0.5 µM[104]
HepatoblastomaHepG2Induced cell-cycle arrest and apoptosis↓ proliferation and migration ability, G2/M arrest, ↓ cyclin A, ↓ cyclin D1, ↑ p21, ↑ early apoptosis, ↓ p- Akt (Ser473), ↑ caspase-8 and PARP,0.001 μM–10 μM[14]
LungA549 cellsInhibits Metastatic Behavior, Cell-cycle arrest and apoptosis↓ proliferation and cell viabilitygradually, ↑ condensation, ↓ p-STAT3 levels, ↑ percentage of cells in G2/M phase, ↑ levels of ROS, ↑ membrane pore formation, ↑ pyroptosis, ↑ caspase-3, 9 activityCucumber-derived nanovesicles (CDNVs)- CDNVs containing 10 nM CuB[15]
A549Apoptosis and microRNA mediated↓ proliferation of lung cancer cells, ↑ cell apoptosis frequency, ↑ Bax and cleaved caspase3, ↓ cyclin B1 and Bcl-2, ↓ XIST and IL-6, ↑ miR-let-7c expression, ↓ IL-6/STAT3 pathway0.1, 0.3, 0.6, and 0.9 μM[52]
A549, A549-GRAnti-metastasis↓ EMT, ↓ p-PI3K, ↓ p-Akt, ↓ p-mTOR5, 10, 15, 20 nM[105]
PC9 (gefitinib resistance)Apoptosis and microRNA mediated↑ miR-17-5p in PC9/GR cells, caspases, STAT3, ↓ p- STAT3--[106]
A549Induced cell-cycle arrest and apoptosis↓ proliferation and migration ability, G2/M arrest, ↓ cyclin A,↓ cyclin D1, ↑ p21, ↑ early apoptosis, ↓ p- Akt (Ser473)0.001 μM–10 μM[14]
A549, NCI-H1299 (H1299), NCI-H1975 (H1975), and NCI-H820 (H820) (gefitinib resistance)Induces apoptosis↓ anchorage-dependent growth and clonogenic ability, ↓ proliferation, invasion and migration ability, ↑ caspase-8 and 3, caspase-3, c-PARP, ↑ Lysosomal Degradation of EGFR and thus Inhibits ERK Signaling, ↓ CIP2A expression, ↑ PP2A, ↓ pAktIC50 (µM)
H1299-0.77
A549-0.76
H197-0.63
H820-0.19
[107]
A549Induces apoptosis↓ cell proliferation, ↑ capase-3/9, ↓ PI3K, p-AKT and p-p70S6K0, 50, 100 and 200 nM[108]
A549Induces autophagy↓ cell viability, colony formation ability, ↑apoptosis frequency, ↑ apoptotic and necrotic, ↑ autophagosomes, ↑ LC3-II/LC3-I, ↓ p-mTOR (S2448), ↓ p- ERK and p- STAT30, 100, 200, 300, 400 and 500 nM[109]
A-549Induces cell-cycle arrest and apoptosis↑ G2/M phase cell-cycle collapse, ↓ m-TOR/PI3K/Akt proteins0, 10, 20, 40, 100, 150 and 200 μM[110]
A549Regulation of cell cycle and induces apoptosis↓ proliferation and colony forming ability, ↑ γH2AX, comet tails were significantly longer, ↑ G2/M phase, ↑ phosphorylation of ATM (Ser-1981), ↑ p- p53(Ser-15)0–800 nM[103]
A549Regulation of cell cycle and induces apoptosis↓ cell proliferation, ↑ G2/M phasecells, % early and lateapoptotic cells, ↑ cell shrinking, ↑ intracytoplasmic vacuoles, ↑chromatin condensation, ↑mitochondrial swelling, ↑caspase-3 and caspase-9, ↑ disruption of the ΔΨm, ↓ (p)-STAT3, ↓ cyclinB1 ↓ Bcl-20.02,0.1, 0.5, 2.5, 12.5 and 62.5 µmol/L[111]
CD133-positive and CD133-negativeInhibits tumorigenic ability and enhances radiochemo-sensitivity↓ STAT3, ↓ tumorigenic capacity,↓ sphere formation ability, ↓ radioresistance and chemoresistance in CD133-positive, ↓ stemness gene signature of CD133-positive, ↓ Bcl-2, ↓ Bcl-xL ↓survivin, ↑ Baxradiation doses (0 Gy, 2Gy, 4 Gy, 6 Gy, 8 Gy, and 10 Gy) + 0, 50, 100 and 150 nM[112]
GastricHuman DDP-resistant gastric cancer cell lineSGC7901/DDP and human GC cell line SGC7901Induces autophagy and apoptosis↓ viability, ↓ clonogenic ability, ↑ cytoplasmic shrinkage, ↓ pro-caspases-3 and -9 and cleaved PARP, ↑ LC3 II and Beclin1, ↓ P-gp, and HIF-1α, ↓ phosphorylation of mTORC1 effectors (mTOR, p70S6K and 4E-BP1), ↓ pAkt, ↑PP2A, ↓ CIP2AIC50 (nM)
SGC7901- 216.70
SGC7901/DDP- 170.25
[113]
MKN-45Cell-cycle arrest, apoptosis↓ proliferation of cancer cells, ↑ progression of the cell cycle from G0/G1 to S phase, ↓ cyclin D1, ↓ cyclin E, ↓ CDK4 and CDK2 (cyclin-dependent kinase), ↑ p27, ↑ cell apoptosis frequency, ↑Bax, ↓ Bcl-2, ↓ JAK2/STAT3 signaling pathway0.1, 1 or 10 µM[114]
ColorectalSW620 and HT29Regulation of cell cycle and apoptosis↑ proliferation and invasion, ↑ chromatin condensation and fragmentation, ↓ pro-cas-3, ↓cleaved PARP, ↓ YAP ↓Cyr 61 and c-Myc, ↑ LATS10, 0.1, 0.2, 0.4, 0.6, 0.8 and 1.0 μM[115]
ProstateLNCaP,
DU145, and PC-3;
Induced cell-cycle arrest and apoptosis↓ proliferation and migration ability, G2/M arrest, ↓ cyclin A,↓ cyclin D1, ↑ p21, ↑ early apoptosis, ↓ p- Akt (Ser473), ↑ caspase-8 and PARP0.001 μM–10 μM[15]
BladderMB49Induce the cell death pathways, apoptosis and autophagy↓ viability of cancer cells, ↓Bcl-2, ↑ LC3II, ↓ phosphorylation of p27, PRAS40 and Raf-1 proteins, ↑ p- AKT, ↓ p-ERK1/ ERK2, ↓ p-mTOR, ↑ BAD, ↑AMPKαCuB- 0.01–50 μM and Cisplatin- 0.5–50 μM[116]
T24Induced cell-cycle arrest and apoptosis↓ proliferation and migration ability, G2/M arrest, ↓ cyclin A,↓ cyclin D1, ↑ p21, ↑ early apoptosis, ↓ p- Akt (Ser473), ↑ caspase-8 and PARP0.001 μM–10 μM[14]
OvarianSKOV3Cell-cycle arrest, apoptosis↑ chromatin condensation, ↑ apoptotic body formation, ↑ deformed cell morphology, ↑ intracellular ROS levels, ↓ MMP, ↓ mTOR/PI3K/Akt signaling pathway, ↓ m-TOR, ↓ phospho m-TOR proteins. ↓ PI3K/Akt protein expressions, ↑ DNA damage, ↑ cell-cycle arrest at G2/M checkpoint0, 10, 20, 40, 80 and 160 μM[117]
Table 2. Antiproliferative actions of cucurbitacins using in vivo investigations.
Table 2. Antiproliferative actions of cucurbitacins using in vivo investigations.
Type of TumorAnimal ModelsEffectsMechanismsDosageDurationReferences
LaryngealNude mice injected with 5 × 106 Hep-2 cellsInhibits tumor growth↓ tumor weight and volume,55 μg/kg/day ofcucurbitacin B, or 7.5 mg/kg/week of docetaxel14 days[100]
Athymic nude mice 5 × 106 Hep-2 cellsInhibits tumor growth↓ tumor growth inhibition, no significant adverse effects were observed55 µg/kg daily for 14 days, orcisplatin (intraperitoneal injection) 10 mg/kg daily14 days[99]
Tongue squamousNude mice injected with SCC9 cell lines (8 × 106)Inhibits tumor growth↓ XIST, XIST expression was lost in XIST KO (knockout)0.5 mg/kg14 days[98]
LungC57BL/6 J mice injected with 5 × 105 B16-F10-Luc cellsAnti-metastasis↓ lung index, ↓ lung metastasisCuB (0.25 mg/kg, and 0.5 mg/kg) groups and Geftinib (40 mg/kg)14 days[105]
BALB/c nude mice injected with A549 cells (2×106 cells)Inhibits tumor growth↓tumor weight, ↑necrotic and apoptotic cells were observed in tumor sections, ↓ p-STAT3, ↓ CD31,CsDNVscontaining 472 nM CuB14 days[15]
nu/nu mice injected with GR NSCLC H1975 cells (2.5 × 106)Inhibits tumor growth↓ tumor weight, ↓ CIP2Aand EGFRgefitinib (30 mg/kg) or CucB 0.5 mg/kg24 days[107]
BALB/c mice injected with 1 × 105 CD133-positive and CD133-negative cellsInhibited tumor growth↓ lung metastasis, ↓ tumor size, ↓ tumorigenic and metastatic capabilities, ↑ survival rate1 mg/kg4 weeks[112]
PancreaticBALB/c-nu injected with BXPC-3cells (2 × 106 cells)Inhibits tumor growth↓ p-STAT3 in the tumors of mice, ↑ PCNA in control1 mg/kg and 2 mg/kg30 days[19]
NOD-SCID gamma mice injected with HPAF-II cells (4 × 106 cells)Inhibits tumor growth↓ MUC13, ↓ PCNA (nuclear proliferating cell antigen), ↑ miRNA-1451 mg/kg40 days[104]
HepatocellularSCID mice injected with HepG2 (3 × 106)Inhibits tumor growthNo significant differences of body weight, ↑ DNA cleavage, ↑ CDKN1A (p21), ↑ CDKN1B (p27), ↑ FOXO, ↑ p- Akt0.1 mg/kg3 weeks[14]
ProstrateSCID mice injected with HepG2 (3 × 106) cellsInhibits tumor growthNo significant differences of body weight, ↑ DNA cleavage, ↑ CDKN1A (p21), ↑ CDKN1B (p27), ↑ FOXO, ↓ p- Akt0.1 mg/kg8 weeks[14]
BladderC57BL/6 injected with 1 × 106 MB49 cellsReduced the tumor growthNo histopathological changes, ↓ Bcl-2, ↑ LC3II, ↓ phosphorylation of p27, PRAS40 and Raf-1 proteins, ↑ p- AKT, ↓ p-ERK1/ ERK2, ↓ p-mTOR,CuB (0.5–1 mg/kg) and Cis (1–3 mg/kg)19 days[116]
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Tuli, H.S.; Rath, P.; Chauhan, A.; Ranjan, A.; Ramniwas, S.; Sak, K.; Aggarwal, D.; Kumar, M.; Dhama, K.; Lee, E.H.C.; et al. Cucurbitacins as Potent Chemo-Preventive Agents: Mechanistic Insight and Recent Trends. Biomolecules 2023, 13, 57. https://doi.org/10.3390/biom13010057

AMA Style

Tuli HS, Rath P, Chauhan A, Ranjan A, Ramniwas S, Sak K, Aggarwal D, Kumar M, Dhama K, Lee EHC, et al. Cucurbitacins as Potent Chemo-Preventive Agents: Mechanistic Insight and Recent Trends. Biomolecules. 2023; 13(1):57. https://doi.org/10.3390/biom13010057

Chicago/Turabian Style

Tuli, Hardeep Singh, Prangya Rath, Abhishek Chauhan, Anuj Ranjan, Seema Ramniwas, Katrin Sak, Diwakar Aggarwal, Manoj Kumar, Kuldeep Dhama, E Hui Clarissa Lee, and et al. 2023. "Cucurbitacins as Potent Chemo-Preventive Agents: Mechanistic Insight and Recent Trends" Biomolecules 13, no. 1: 57. https://doi.org/10.3390/biom13010057

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