Antitumor Agents from Natural Sources

A special issue of Biomolecules (ISSN 2218-273X). This special issue belongs to the section "Natural and Bio-inspired Molecules".

Deadline for manuscript submissions: closed (31 December 2019) | Viewed by 147210

Special Issue Editor

Special Issue Information

Dear Colleagues,

This special issue aims to highlight the pleiotropic mechanism(s) underlying the processes of cancer initiation as well as progression and focus on the antitumor properties of agents derived from Natural sources. Several small molecules isolated from plants, fruits, vegetables, spices etc have demonstrated significant efficacy against various malignancies. These agents can suppress different characteristic hall marks of cancer cell and have been investigated in various preclinical as well a clinical studies. This issue will highlight the potential role of such important natural agents I both cancer prevention and therapy.

I look forward to your contributions,

Prof. Gautam Sethi
Guest Editor

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Keywords

  • cancer
  • natural products
  • metastasis
  • angiogenesis
  • preclinical models

Published Papers (26 papers)

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16 pages, 3278 KiB  
Article
2α-Hydroxyeudesma-4,11(13)-Dien-8β,12-Olide Isolated from Inula britannica Induces Apoptosis in Diffuse Large B-cell Lymphoma Cells
by Dae Kil Jang, Ik-Soo Lee, Han-Seung Shin and Hee Min Yoo
Biomolecules 2020, 10(2), 324; https://doi.org/10.3390/biom10020324 - 18 Feb 2020
Cited by 13 | Viewed by 3548
Abstract
2α-Hydroxyeudesma-4,11(13)-dien-8β,12-olide (HEDO), a eudesmane-type sesquiterpene lactone belonging to large group of plant terpenoids isolated from Inula britannica, displays cytotoxic activity against diffuse large B cell lymphoma cells in vitro. However, the molecular mechanism of the anticancer effect remains unclear. In this study, [...] Read more.
2α-Hydroxyeudesma-4,11(13)-dien-8β,12-olide (HEDO), a eudesmane-type sesquiterpene lactone belonging to large group of plant terpenoids isolated from Inula britannica, displays cytotoxic activity against diffuse large B cell lymphoma cells in vitro. However, the molecular mechanism of the anticancer effect remains unclear. In this study, we showed that HEDO inhibits cell growth by inducing apoptosis in lymphoma cell lines through its antiproliferative activity. HEDO increases the depolarization of mitochondrial membrane potential and upregulated intracellular reactive oxygen species (ROS). Furthermore, we examined the cell cycle effect, and our results provided evidence that the arrest of the cell cycle at the SubG0/G1 phase plays an important role in the ability of HEDO to inhibit cell growth in Ontario Cancer Institute (OCI)-LY3 lymphoma cells by preventing nuclear factor-kappa B (NF-κB) signaling. In addition, HEDO induced apoptosis by instigating the activation of Bcl-2-associated X (BAX) and cleaved caspase-3, decreasing B-cell lymphoma 2 (BCL2), B-cell lymphoma-extra large (BCL-XL), and procaspase 3 expression levels. Based on these findings, we suggest that HEDO has potential as an anticancer drug of lymphoma by inducing ROS-dependent accumulation of SubG0/G1 arrest and apoptosis in OCI-LY3 cells. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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13 pages, 3576 KiB  
Article
Oxidized Products of α-Linolenic Acid Negatively Regulate Cellular Survival and Motility of Breast Cancer Cells
by Jorge L. Gutierrez-Pajares, Celine Ben Hassen, Camille Oger, Jean-Marie Galano, Thierry Durand and Philippe G. Frank
Biomolecules 2020, 10(1), 50; https://doi.org/10.3390/biom10010050 - 28 Dec 2019
Cited by 9 | Viewed by 3750
Abstract
Despite recent advances in our understanding of the biological processes leading to the development and progression of cancer, there is still a need for new and effective agents to treat this disease. Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) are non-enzymatically oxidized products of α-linolenic [...] Read more.
Despite recent advances in our understanding of the biological processes leading to the development and progression of cancer, there is still a need for new and effective agents to treat this disease. Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) are non-enzymatically oxidized products of α-linolenic acid that are present in seeds and vegetable oils. They have been shown to possess anti-inflammatory and apoptosis-promoting activities in macrophages and leukemia cells, respectively. In this work, seven PhytoPs (PP1–PP7) and one PhytoFs (PF1) were evaluated for their cytotoxic, chemosensitization, and anti-migratory activities using the MCF-7 and MDA-MB-231 breast cancer cell lines. Among the tested compounds, only three PhytoPs had a significant effect on cell viability compared to the control group: Ent-9-L1-PhytoP (PP6) decreased cell viability in both cell lines, while 16-F1t-PhytoP (PP1) and 9-L1-PhytoP (PP5) decreased viability of MCF-7 and MDA-MB-231 cells, respectively. When combined with a sub-cytotoxic dose of doxorubicin, these three PhytoPs displayed significantly enhanced cytotoxic effects on MCF-7 cells while the chemotherapeutic drug alone had no effect. In cellular motility assays, Ent-9-(RS)-12-epi-ST-Δ10-13-PhytoF could significantly inhibit cellular migration of MDA-MB-231 cells. In addition, Ent-9-(RS)-12-epi-ST-Δ10-13-PhytoF also enhanced cellular adhesion of MDA-MB-231 cells. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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20 pages, 1999 KiB  
Article
Advancing the Role of Gamma-Tocotrienol as Proteasomes Inhibitor: A Quantitative Proteomic Analysis of MDA-MB-231 Human Breast Cancer Cells
by Premdass Ramdas, Ammu Kutty Radhakrishnan, Asmahani Azira Abdu Sani, Mangala Kumari, Jeya Seela Anandha Rao and Puteri Shafinaz Abdul-Rahman
Biomolecules 2020, 10(1), 19; https://doi.org/10.3390/biom10010019 - 21 Dec 2019
Cited by 16 | Viewed by 3842
Abstract
Tocotrienol, an analogue of vitamin E has been known for its numerous health benefits and anti-cancer effects. Of the four isoforms of tocotrienols, gamma-tocotrienol (γT3) has been frequently reported for their superior anti-tumorigenic activity in both in vitro and in vivo studies, when [...] Read more.
Tocotrienol, an analogue of vitamin E has been known for its numerous health benefits and anti-cancer effects. Of the four isoforms of tocotrienols, gamma-tocotrienol (γT3) has been frequently reported for their superior anti-tumorigenic activity in both in vitro and in vivo studies, when compared to its counterparts. In this study, the effect of γT3 treatment in the cytoplasmic and nuclear fraction of MDA-MB-231 human breast cancer cells were assessed using the label-free quantitative proteomics analysis. The cytoplasmic proteome results revealed the ability of γT3 to inhibit a group of proteasome proteins such as PSMA, PSMB, PSMD, and PSME. The inhibition of proteasome proteins is known to induce apoptosis in cancer cells. As such, the findings from this study suggest γT3 as a potential proteasome inhibitor that can overcome deficiencies in growth-inhibitory or pro-apoptotic molecules in breast cancer cells. The nuclear proteome results revealed the involvement of important nuclear protein complexes which hardwire the anti-tumorigenesis mechanism in breast cancer following γT3 treatment. In conclusion, this study uncovered the advancing roles of γT3 as potential proteasomes inhibitor that can be used for the treatment of breast cancer. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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22 pages, 4166 KiB  
Article
Lagerstroemia Speciosa (L.) Pers Leaf Extract Attenuates Lung Tumorigenesis via Alleviating Oxidative Stress, Inflammation and Apoptosis
by Amria M. Mousa, Nermin M. El-Sammad, Abeer H. Abdel-Halim, Nayera Anwar, Wagdy K. B. Khalil, Mahmoud Nawwar, Amani N. Hashim, Elsayed A. Elsayed and Sherien K. Hassan
Biomolecules 2019, 9(12), 871; https://doi.org/10.3390/biom9120871 - 12 Dec 2019
Cited by 15 | Viewed by 4937
Abstract
One of the major etiological factors that account for lung cancer is tobacco use. Benzo(a)pyrene [B(a)P], one of the main constituents of tobacco smoke, has a key role in lung carcinogenesis. The present study was conducted to investigate the cytotoxicity of an aqueous [...] Read more.
One of the major etiological factors that account for lung cancer is tobacco use. Benzo(a)pyrene [B(a)P], one of the main constituents of tobacco smoke, has a key role in lung carcinogenesis. The present study was conducted to investigate the cytotoxicity of an aqueous ethanolic extract of Lagerstroemia speciosa (L.) Pers leaves (LLE) on human lung adenocarcinoma cells (A549), as well as its in vivo antitumor effect on a lung tumorigenesis mice model. Our results revealed that LLE possesses cytotoxic activity against the A549 cell line. Mice orally administered B(a)P (50 mg/kg body weight) showed an increase in relative lung weight with subsequent decrease in final body weight. Serum levels of tumor marker enzymes AHH, ADA and LDH and the inflammatory mediator NF-κB increased, while total antioxidant capacity (TAC) decreased. In addition, we observed the increased activity of metalloproteinases (MMP-2 and MMP-12) and levels of the tumor angiogenesis marker VEFG and the lipid peroxidation marker MDA, as well as decreased levels of the non-enzymatic antioxidant GSH and enzymatic antioxidants CAT and GSH-Px in lung tissues. Moreover, B(a)P administration up-regulated the expression of the COX-2 gene, pro-inflammatory cytokines TNF-α and IL-6, and an anti-apoptotic gene Bcl-2, and at the same time down-regulated expression of pro-apoptotic genes BAX and caspase-3 and the p53 gene. Pre- and post-treatment with LLE (250 mg/kg body weight) attenuated all these abnormalities. Histopathological observations verified the protective effect of LLE. Overall, the present data positively confirm the potent antitumor effect of L. speciosa leaves against lung tumorigenesis. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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23 pages, 7711 KiB  
Article
TIPE2 Induced the Proliferation, Survival, and Migration of Lung Cancer Cells Through Modulation of Akt/mTOR/NF-κB Signaling Cascade
by Devivasha Bordoloi, Kishore Banik, Ganesan Padmavathi, Rajesh Vikkurthi, Choudhary Harsha, Nand Kishor Roy, Anuj Kumar Singh, Javadi Monisha, Hong Wang, Alan Prem Kumar and Ajaikumar B Kunnumakkara
Biomolecules 2019, 9(12), 836; https://doi.org/10.3390/biom9120836 - 6 Dec 2019
Cited by 44 | Viewed by 4096
Abstract
Lung cancer represents the most common cause of cancer deaths in the world, constituting around 11.6% of all new cancer cases and 18.4% of cancer-related deaths. The propensity for early spread, lack of suitable biomarkers for early diagnosis, as well as prognosis and [...] Read more.
Lung cancer represents the most common cause of cancer deaths in the world, constituting around 11.6% of all new cancer cases and 18.4% of cancer-related deaths. The propensity for early spread, lack of suitable biomarkers for early diagnosis, as well as prognosis and ineffective existing therapies, contribute to the poor survival rate of lung cancer. Therefore, there is an urgent need to develop novel biomarkers for early diagnosis and prognosis which in turn can facilitate newer therapeutic avenues for the management of this aggressive neoplasm. TIPE2 (tumor necrosis factor-α-induced protein 8-like 2), a recently identified cytoplasmic protein, possesses enormous potential in this regard. Immunohistochemical analysis showed that TIPE2 was significantly upregulated in different stages and grades of lung cancer tissues compared to normal lung tissues, implying its involvement in the positive regulation of lung cancer. Further, knockout of TIPE2 resulted in significantly reduced proliferation, survival, and migration of human lung cancer cells through modulation of the Akt/mTOR/NF-κB signaling axis. In addition, knockout of TIPE2 also caused arrest in the S phase of the cell cycle of lung cancer cells. As tobacco is the most predominant risk factor for lung cancer, we therefore evaluated the effect of TIPE2 in tobacco-mediated lung carcinogenesis as well. Our results showed that TIPE2 was involved in nicotine-, nicotine-derived nitrosamine ketone (NNK)-, N-nitrosonornicotine (NNN)-, and benzo[a]pyrene (BaP)-mediated lung cancer through inhibited proliferation, survival, and migration via modulation of nuclear factor kappa B (NF-κB)- and NF-κB-regulated gene products, which are involved in the regulation of diverse processes in lung cancer cells. Taken together, TIPE2 possesses an important role in the development and progression of lung cancer, particularly in tobacco-promoted lung cancer, and hence, specific targeting of it holds an enormous prospect in newer therapeutic interventions in lung cancer. However, these findings need to be validated in the in vivo and clinical settings to fully establish the diagnostic and prognostic importance of TIPE2 against lung cancer. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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13 pages, 5253 KiB  
Article
Lichen Secondary Metabolite Physciosporin Decreases the Stemness Potential of Colorectal Cancer Cells
by Yi Yang, Thanh Thi Nguyen, Iris Pereira, Jae-Seoun Hur and Hangun Kim
Biomolecules 2019, 9(12), 797; https://doi.org/10.3390/biom9120797 - 28 Nov 2019
Cited by 10 | Viewed by 4809
Abstract
Secondary metabolites of lichens are promising bioresources for candidate anti-cancer drugs. Accordingly, several approaches have been proposed for screening these molecules for novel anti-cancer lead compounds. In this study, we found that a non-toxic concentration of physciosporin, a compound isolated from Pseudocyphellaria granulata [...] Read more.
Secondary metabolites of lichens are promising bioresources for candidate anti-cancer drugs. Accordingly, several approaches have been proposed for screening these molecules for novel anti-cancer lead compounds. In this study, we found that a non-toxic concentration of physciosporin, a compound isolated from Pseudocyphellaria granulata, significantly decreased colony formation on soft agar and spheroid formation by CSC221 cancer stem-like cells. Physciosporin also decreased spheroid formation in other colorectal cancer cell lines, including DLD1, Caco2, and HT29. Aldehyde dehydrogenase-1 (ALDH1), the most important cancer stem marker, was sharply downregulated at both the protein and mRNA level following treatment with physciosporin. Physciosporin also decreased the transcriptional activity of the glioma-associated oncogene homolog zinc finger protein (Gli), as well as the Hes1 and CSL promoters, in reporter assays. Moreover, the drug significantly suppressed spheroid formation in CSC221 cells overexpressing Gli1/2 or ΔEN1 (an S2-cleaved but membrane-tethered form of human Notch1) but did not suppress spheroid formation in cells overexpressing both Gli1/2 and ∆EN1, suggesting that physciosporin suppresses colon cancer cell stemness through the Sonic hedgehog and Notch signaling pathways. Together, these results demonstrate for the first time that physciosporin is a potent inhibitor of colorectal cancer cell stemness. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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20 pages, 4211 KiB  
Article
Lanatoside C Induces G2/M Cell Cycle Arrest and Suppresses Cancer Cell Growth by Attenuating MAPK, Wnt, JAK-STAT, and PI3K/AKT/mTOR Signaling Pathways
by Dhanasekhar Reddy, Ranjith Kumavath, Preetam Ghosh and Debmalya Barh
Biomolecules 2019, 9(12), 792; https://doi.org/10.3390/biom9120792 - 27 Nov 2019
Cited by 68 | Viewed by 6935
Abstract
Cardiac glycosides (CGs) are a diverse family of naturally derived compounds having a steroid and glycone moiety in their structures. CG molecules inhibit the α-subunit of ubiquitous transmembrane protein Na+/K+-ATPase and are clinically approved for the treatment of cardiovascular [...] Read more.
Cardiac glycosides (CGs) are a diverse family of naturally derived compounds having a steroid and glycone moiety in their structures. CG molecules inhibit the α-subunit of ubiquitous transmembrane protein Na+/K+-ATPase and are clinically approved for the treatment of cardiovascular diseases. Recently, the CGs were found to exhibit selective cytotoxic effects against cancer cells, raising interest in their use as anti-cancer molecules. In this current study, we explored the underlying mechanism responsible for the anti-cancer activity of Lanatoside C against breast (MCF-7), lung (A549), and liver (HepG2) cancer cell lines. Using Real-time PCR, western blot, and immunofluorescence studies, we observed that (i) Lanatoside C inhibited cell proliferation and induced apoptosis in cell-specific and dose-dependent manner only in cancer cell lines; (ii) Lanatoside C exerts its anti-cancer activity by arresting the G2/M phase of cell cycle by blocking MAPK/Wnt/PAM signaling pathways; (iii) it induces apoptosis by inducing DNA damage and inhibiting PI3K/AKT/mTOR signaling pathways; and finally, (iv) molecular docking analysis shows significant evidence on the binding sites of Lanatoside C with various key signaling proteins ranging from cell survival to cell death. Our studies provide a novel molecular insight of anti-cancer activities of Lanatoside C in human cancer cells. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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15 pages, 3587 KiB  
Article
Amazon Fruits Inhibit Growth and Promote Pro-apoptotic Effects on Human Ovarian Carcinoma Cell Lines
by Vanessa Rosse de Souza, Mariana Concentino Menezes Brum, Isabella dos Santos Guimarães, Paula de Freitas dos Santos, Thuane Oliveira do Amaral, Joel Pimentel Abreu, Thuane Passos, Otniel Freitas-Silva, Etel Rodrigues Pereira Gimba and Anderson Junger Teodoro
Biomolecules 2019, 9(11), 707; https://doi.org/10.3390/biom9110707 - 6 Nov 2019
Cited by 13 | Viewed by 3147
Abstract
Murici (Byrsonima crassifolia (L.) Kunth and B. verbascifolia (L.) DC.) and tapereba (Spondias mombin) are Amazonian fruits that contain bioactive compounds. Biochemical and molecular characterization of these fruits can reveal their potential use in preventing diseases, including cancer. The extracts [...] Read more.
Murici (Byrsonima crassifolia (L.) Kunth and B. verbascifolia (L.) DC.) and tapereba (Spondias mombin) are Amazonian fruits that contain bioactive compounds. Biochemical and molecular characterization of these fruits can reveal their potential use in preventing diseases, including cancer. The extracts were characterized regarding the presence and profile of carotenoids by high-performance liquid chromatography (HPLC), total phenolic content by the Folin–Ciocalteu assay, and antioxidant activity by antioxidant value 2,2-diphenyl-1-picrylhydrazyl (DPPH) content analysis, 22,20-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) content analysis, Ferric-Reducing Ability of Plasma (FRAP), and Oxygen Radical Absorbance Capacity (ORAC) analysis. The extracts of tapereba and murici studied were important sources of total carotenoids and lutein, respectively. The extracts were then tested for their effect on the viability of the A2780 ovarian cancer (OC) cell line and its cisplatin (CDDP)-resistant derived cell line, called ACRP, by using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays. Their influence on cell cycle and apoptosis were analyzed by using flow cytometry. Murici and tapereba cell extracts exhibited a strong bioactivity by inhibiting A2780 and ACRP cell viability by 76.37% and 78.37%, respectively, besides modulating the cell cycle and inducing apoptotic cell death. Our results open new perspectives for the development of innovative therapeutic strategies using these Amazon fruit extracts to sensitize ovarian cancer cells to current chemotherapeutic options. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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15 pages, 3861 KiB  
Article
Anti-Cancer Effects of Synergistic Drug–Bacterium Combinations on Induced Breast Cancer in BALB/c Mice
by Menaga Subramaniam, Norhafiza M. Arshad, Kein Seong Mun, Sharan Malagobadan, Khalijah Awang and Noor Hasima Nagoor
Biomolecules 2019, 9(10), 626; https://doi.org/10.3390/biom9100626 - 18 Oct 2019
Cited by 4 | Viewed by 2551
Abstract
Cancer development and progression are extremely complex due to the alteration of various genes and pathways. In most cases, multiple agents are required to control cancer progression. The purpose of this study is to investigate, using a mouse model, the synergistic interactions of [...] Read more.
Cancer development and progression are extremely complex due to the alteration of various genes and pathways. In most cases, multiple agents are required to control cancer progression. The purpose of this study is to investigate, using a mouse model, the synergistic interactions of anti-cancer agents, 1′-S-1′-acetoxychavicol acetate (ACA), Mycobacterium indicus pranii (MIP), and cisplatin (CDDP) in double and triple combinations to treat chemo-sensitize and immune-sensitize breast cancer. Changes in tumor volume and body weight were monitored. Organs were harvested and stained using hematoxylin–eosin for histopathological assessment. Milliplex enzyme-linked immunosorbent assay (ELISA) was performed to determine cytokine levels, while immunohistochemistry (IHC) was conducted on tumor biopsies to verify systemic drug effects. In vivo mouse models showed tumor regression with maintenance of regular body weight for all the different treatment regimens. IHC results provided conclusive evidence indicating that combination regimens were able to down-regulate nuclear factor kappa-B activation and reduce the expression of its regulated pro-inflammatory proteins. Reduction of pro-inflammatory cytokines (e.g., IL-6, TNF-α, and IFN-ɣ) levels were observed when using the triple combination, which indicated that the synergistic drug combination was able to significantly control cancer progression. In conclusion, ACA, MIP, and CDDP together serve as promising candidates for further development and for subsequent clinical trials against estrogen-sensitive breast cancer. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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13 pages, 1388 KiB  
Article
Parvifloron D from Plectranthus strigosus: Cytotoxicity Screening of Plectranthus spp. Extracts
by Catarina Garcia, Epole Ntungwe, Ana Rebelo, Cláudia Bessa, Tijana Stankovic, Jelena Dinic, Ana Díaz-Lanza, Catarina P. Reis, Amílcar Roberto, Paula Pereira, Maria-João Cebola, Lucília Saraiva, Milica Pesic, Noélia Duarte and Patrícia Rijo
Biomolecules 2019, 9(10), 616; https://doi.org/10.3390/biom9100616 - 17 Oct 2019
Cited by 10 | Viewed by 3568
Abstract
The Plectranthus genus is commonly used in traditional medicine due to its potential to treat several illnesses, including bacterial infections and cancer. As such, aiming to screen the antibacterial and cytotoxic activities of extracts, sixteen selected Plectranthus species with medicinal potential were studied. [...] Read more.
The Plectranthus genus is commonly used in traditional medicine due to its potential to treat several illnesses, including bacterial infections and cancer. As such, aiming to screen the antibacterial and cytotoxic activities of extracts, sixteen selected Plectranthus species with medicinal potential were studied. In total, 31 extracts obtained from 16 Plectranthus spp. were tested for their antibacterial and anticancer properties. Well diffusion method was used for preliminary antibacterial screening. The minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values of the five most active acetonic extracts (P. aliciae, P. japonicus, P. madagascariensis var. “Lynne”, P. stylesii, and P. strigosus) were determined. After preliminary toxicity evaluation on Artemia salina L., their cytotoxic properties were assessed on three human cancer cell lines (HCT116, MCF-7, and H460). These were also selected for mechanism of resistance studies (on NCI-H460/R and DLD1-TxR cells). An identified compound—parvifloron D—was tested in a pair of sensitive and MDR-Multidrug resistance cancer cells (NCI-H460 and NCI-H460/R) and in normal bronchial fibroblasts MRC-5. The chemical composition of the most active extract was studied through high performance liquid chromatography with a diode array detector (HPLC-DAD/UV) and liquid chromatography–mass spectrometry (LC–MS). Overall, P. strigosus acetonic extract showed the strongest antimicrobial and cytotoxic potential that could be explained by the presence of parvifloron D, a highly cytotoxic diterpene. This study provides valuable information on the use of the Plectranthus genus as a source of bioactive compounds, namely P. strigosus with the potential active ingredient the parvifloron D. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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17 pages, 2706 KiB  
Article
Brusatol, a Nrf2 Inhibitor Targets STAT3 Signaling Cascade in Head and Neck Squamous Cell Carcinoma
by Jong Hyun Lee, Shobith Rangappa, Chakrabhavi Dhananjaya Mohan, Basappa, Gautam Sethi, Zhi-Xiu Lin, Kanchugarakoppal S. Rangappa and Kwang Seok Ahn
Biomolecules 2019, 9(10), 550; https://doi.org/10.3390/biom9100550 - 30 Sep 2019
Cited by 59 | Viewed by 4735
Abstract
STAT3 is a latent transcription factor that plays a vital role in the transmission of extracellular signal from receptors to the nucleus. It has been regarded as a master transcription factor due to its role in the regulation of a broad spectrum of [...] Read more.
STAT3 is a latent transcription factor that plays a vital role in the transmission of extracellular signal from receptors to the nucleus. It has been regarded as a master transcription factor due to its role in the regulation of a broad spectrum of genes, which can contribute to oncogenesis. Persistent activation of STAT3 and deregulation of its signaling has been observed in various human cancers including head and neck squamous cell carcinoma (HNSCC). In the present work, we identified brusatol (BT) as a potential blocker of STAT3 signaling pathway in diverse HNSCC cells. The data from the cell-based experiments suggested that BT-induced cytotoxicity and abrogated the activation of STAT3 and that of upstream kinases such as JAK1, JAK2, and Src. It reduced the levels of nuclear STAT3 and its DNA binding ability. BT treatment increased annexin-V-positive cells, promoted procaspase-3 and PARP cleavage, and downregulated the mRNA and protein expression of diverse proteins (Bcl-2, Bcl-xl, survivin) in HNSCC cells. Taken together, brusatol can function as a promising inhibitor targeting STAT3 signaling pathway in HNSCC. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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16 pages, 3320 KiB  
Article
Crinamine Induces Apoptosis and Inhibits Proliferation, Migration, and Angiogenesis in Cervical Cancer SiHa Cells
by Phattharachanok Khumkhrong, Kitiya Piboonprai, Waraluck Chaichompoo, Wittaya Pimtong, Mattaka Khongkow, Katawut Namdee, Angkana Jantimaporn, Deanpen Japrung, Udom Asawapirom, Apichart Suksamrarn and Tawin Iempridee
Biomolecules 2019, 9(9), 494; https://doi.org/10.3390/biom9090494 - 16 Sep 2019
Cited by 15 | Viewed by 4238
Abstract
Crinum asiaticum is a perennial herb widely distributed in many warmer regions, including Thailand, and is well-known for its medicinal and ornamental values. Crinum alkaloids contain numerous compounds, such as crinamine. Even though its mechanism of action is still unknown, crinamine was previously [...] Read more.
Crinum asiaticum is a perennial herb widely distributed in many warmer regions, including Thailand, and is well-known for its medicinal and ornamental values. Crinum alkaloids contain numerous compounds, such as crinamine. Even though its mechanism of action is still unknown, crinamine was previously shown to possess anticancer activity. In this study, we demonstrate that crinamine was more cytotoxic to cervical cancer cells than normal cells. It also inhibited anchorage-independent tumor spheroid growth more effectively than existing chemotherapeutic drugs carboplatin and 5-fluorouracil or the CDK9 inhibitor FIT-039. Additionally, unlike cisplatin, crinamine induced apoptosis without promoting DNA double-strand breaks. It suppressed cervical cancer cell migration by inhibiting the expression of positive regulators of epithelial-mesenchymal transition SNAI1 and VIM. Importantly, crinamine also exerted anti-angiogenic activities by inhibiting secretion of VEGF-A protein in cervical cancer cells and blood vessel development in zebrafish embryos. Gene expression analysis revealed that its mechanism of action might be attributed, in part, to downregulation of cancer-related genes, such as AKT1, BCL2L1, CCND1, CDK4, PLK1, and RHOA. Our findings provide a first insight into crinamine’s anticancer activity, highlighting its potential use as an alternative bioactive compound for cervical cancer chemoprevention and therapy. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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11 pages, 2323 KiB  
Article
Quercetin Interrupts the Positive Feedback Loop Between STAT3 and IL-6, Promotes Autophagy, and Reduces ROS, Preventing EBV-Driven B Cell Immortalization
by Marisa Granato, Maria Saveria Gilardini Montani, Claudia Zompetta, Roberta Santarelli, Roberta Gonnella, Maria Anele Romeo, Gabriella D’Orazi, Alberto Faggioni and Mara Cirone
Biomolecules 2019, 9(9), 482; https://doi.org/10.3390/biom9090482 - 12 Sep 2019
Cited by 27 | Viewed by 5131
Abstract
The oncogenic gammaherpesvirus Epstein–Barr virus (EBV) immortalizes in vitro B lymphocytes into lymphoblastoid cell lines (LCLs), a model that gives the opportunity to explore the molecular mechanisms driving viral tumorigenesis. In this study, we addressed the potential of quercetin, a widely distributed flavonoid [...] Read more.
The oncogenic gammaherpesvirus Epstein–Barr virus (EBV) immortalizes in vitro B lymphocytes into lymphoblastoid cell lines (LCLs), a model that gives the opportunity to explore the molecular mechanisms driving viral tumorigenesis. In this study, we addressed the potential of quercetin, a widely distributed flavonoid displaying antioxidant, anti-inflammatory, and anti-cancer properties, in preventing EBV-driven B cell immortalization. The results obtained indicated that quercetin inhibited thectivation of signal transducer and activator of transcription 3 (STAT3) induced by EBV infection and reduced molecules such as interleukin-6 (IL-6) and reactive oxidative species (ROS) known to be essential for the immortalization process. Moreover, we found that quercetin promoted autophagy and counteracted the accumulation of sequestosome1/p62 (SQSTM1/p62), ultimately leading to the prevention of B cell immortalization. These findings suggest that quercetin may have the potential to be used to counteract EBV-driven lymphomagenesis, especially if its stability is improved. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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14 pages, 2107 KiB  
Article
Antrodia cinnamomea Enhances Chemo-Sensitivity of 5-FU and Suppresses Colon Tumorigenesis and Cancer Stemness via Up-Regulation of Tumor Suppressor miR-142-3p
by Yan-Jiun Huang, Vijesh Kumar Yadav, Prateeti Srivastava, Alexander TH Wu, Thanh-Tuan Huynh, Po-Li Wei, Chi-Ying F. Huang and Tse-Hung Huang
Biomolecules 2019, 9(8), 306; https://doi.org/10.3390/biom9080306 - 25 Jul 2019
Cited by 15 | Viewed by 4359
Abstract
5-Fluorouracil (5-FU) regimen remains the backbone of the first-line agent to treat colon cancer, but often these patients develop resistance. Cancer stem cells (CSC’s) are considered as one of the key contributors in the development of drug resistance and tumor recurrence. We aimed [...] Read more.
5-Fluorouracil (5-FU) regimen remains the backbone of the first-line agent to treat colon cancer, but often these patients develop resistance. Cancer stem cells (CSC’s) are considered as one of the key contributors in the development of drug resistance and tumor recurrence. We aimed to provide preclinical evidence for Antrodia cinnamomea (AC), as a potential in suppressing colon cancer CSC’s to overcome 5-FU drug-resistant. In-vitro assays including cell viability, colony formation, AC + 5-FU drug combination index and tumor sphere generation were applied to determine the inhibitory effect of AC. Mouse xenograft models also incorporated to evaluate in vivo effect of AC. AC treatment significantly inhibited the proliferation, colony formation and tumor sphere generation. AC also inhibited the expression of oncogenic markers (NF-κB, and C-myc), EMT/metastasis markers (vimentin and MMP3) and stemness associated markers (β-catenin, SOX-2 and Nanog). Sequential treatment of AC and 5-FU synergized and reduces colon cancer viability both in vivo and in vitro. Mechanistically, AC mediated anti-tumor effect was associated with an increased level of tumor suppressor microRNAs especially, miR142-3p. AC can be a potent synergistic adjuvant, down-regulates cancer stemness genes and enhances the antitumor ability of 5-FU by stimulating apoptosis-associated genes, suppressing inflammation and metastasis genes through miR142-3p in colon cancer. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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17 pages, 2970 KiB  
Article
A Sesquiterpenoid from Farfarae Flos Induces Apoptosis of MDA-MB-231 Human Breast Cancer Cells through Inhibition of JAK–STAT3 Signaling
by Hyeri Jang, Hyejin Ko, Kwangho Song and Yeong Shik Kim
Biomolecules 2019, 9(7), 278; https://doi.org/10.3390/biom9070278 - 13 Jul 2019
Cited by 22 | Viewed by 4731
Abstract
Triple-negative breast cancers (TNBCs) are hard-to-treat breast tumors with poor prognosis, which need to be treated by chemotherapy. Signal transducer and activator of transcription 3 (STAT3) is a transcription factor involved in proliferation, metastasis, and invasion of cancer cells. Therefore, research on searching [...] Read more.
Triple-negative breast cancers (TNBCs) are hard-to-treat breast tumors with poor prognosis, which need to be treated by chemotherapy. Signal transducer and activator of transcription 3 (STAT3) is a transcription factor involved in proliferation, metastasis, and invasion of cancer cells. Therefore, research on searching for promising compounds with metabolism that suppress phosphorylation or transcription of STAT3 in TNBC cells is important. Farfarae Flos is well known as a traditional medicine for treating inflammation. However, few studies have shown that sesquiterpenoids from Farfarae Flos have an anticancer effect. In this study, efficient separation methods and an MTT assay were conducted to isolate an anticancer compound from Farfarae Flos against TNBC MDA-MB-231 cells. Here, 7β-(3-Ethyl-cis-crotonoyloxy)-1α-(2-methylbutyryloxy)-3,14-dehydro-Z-notonipetranone (ECN), a compound isolated from Farfarae Flos showed a potent cytotoxic effect on MDA-MB-231 cells. ECN inhibited JAK–STAT3 signaling and suppressed the expression of STAT3 target genes. In addition, ECN induced apoptosis through both extrinsic and intrinsic pathways. Furthermore, we investigated that ECN inhibited the growth of tumors by intraperitoneal administration in mice injected with MDA-MB-231 cells. Therefore, ECN can be an effective chemotherapeutic agent for breast cancer treatment. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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17 pages, 5556 KiB  
Article
Formononetin Regulates Multiple Oncogenic Signaling Cascades and Enhances Sensitivity to Bortezomib in a Multiple Myeloma Mouse Model
by Chulwon Kim, Jong Hyun Lee, Jeong-Hyeon Ko, Arunachalam Chinnathambi, Sulaiman Ali Alharbi, Omar H.M. Shair, Gautam Sethi and Kwang Seok Ahn
Biomolecules 2019, 9(7), 262; https://doi.org/10.3390/biom9070262 - 7 Jul 2019
Cited by 27 | Viewed by 3523
Abstract
Here, we determined the anti-neoplastic actions of formononetin (FT) against multiple myeloma (MM) and elucidated its possible mode of action. It was observed that FT enhanced the apoptosis caused by bortezomib (Bor) and mitigated proliferation in MM cells, and these events are regulated [...] Read more.
Here, we determined the anti-neoplastic actions of formononetin (FT) against multiple myeloma (MM) and elucidated its possible mode of action. It was observed that FT enhanced the apoptosis caused by bortezomib (Bor) and mitigated proliferation in MM cells, and these events are regulated by nuclear factor-κB (NF-κB), phosphatidylinositol 3-kinase (PI3K)/AKT, and activator protein-1 (AP-1) activation. We further noted that FT treatment reduced the levels of diverse tumorigenic proteins involved in myeloma progression and survival. Interestingly, we observed that FT also blocked persistent NF-κB, PI3K/AKT, and AP-1 activation in myeloma cells. FT suppressed the activation of these oncogenic cascades by affecting a number of signaling molecules involved in their cellular regulation. In addition, FT augmented tumor growth-inhibitory potential of Bor in MM preclinical mouse model. Thus, FT can be employed with proteasomal inhibitors for myeloma therapy by regulating the activation of diverse oncogenic transcription factors involved in myeloma growth. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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12 pages, 2793 KiB  
Article
Halogen-Substituted Derivatives of Dictyostelium Differentiation-Inducing Factor-1 Suppress Serum-Induced Cell Migration of Human Breast Cancer MDA-MB-231 Cells in Vitro
by Kyoko Totsuka, Yuka Makioka, Kyoichi Iizumi, Katsunori Takahashi, Yoshiteru Oshima, Haruhisa Kikuchi and Yuzuru Kubohara
Biomolecules 2019, 9(7), 256; https://doi.org/10.3390/biom9070256 - 28 Jun 2019
Cited by 6 | Viewed by 3226
Abstract
Triple-negative breast cancer (TNBC) is highly proliferative and metastatic, and because it lacks three major molecular targets for chemotherapy (estrogen receptor, progesterone receptor, and human epidermal receptor 2), it is extremely refractory. Differentiation-inducing factor 1 (DIF-1) and DIF-3, which are chlorinated alkylphenones, are [...] Read more.
Triple-negative breast cancer (TNBC) is highly proliferative and metastatic, and because it lacks three major molecular targets for chemotherapy (estrogen receptor, progesterone receptor, and human epidermal receptor 2), it is extremely refractory. Differentiation-inducing factor 1 (DIF-1) and DIF-3, which are chlorinated alkylphenones, are lead anticancer compounds found in the cellular slime mold Dictyostelium discoideum. Here, we examined the in vitro effects of DIF-1, DIF-3, and 25 DIF derivatives on cell proliferation and serum-induced cell migration in human MDA-MB-231 cells, a model TNBC cell line. We found that Br-DIF-1, a chlorine-to-bromine-substituted derivative of DIF-1, strongly suppressed cell migration (IC50, 3.8 μM) with negligible effects on cell proliferation (IC50, >20 μM). We then synthesized 18 derivatives of Br-DIF-1 and examined the in vitro effects of these derivatives on cell proliferation and serum-induced cell migration in MDA-MB-231 cells. Among the derivatives, Br-DIF-1(+1), Br-DIF-1(+2), and Br-DIF-3(+2) exhibited strong anti-cell migration activities with IC50 values of 1.5, 1.0, and 3.1 μM, respectively, without affecting cell proliferation (IC50, >20 μM). These results suggest that these Br-DIF derivatives are good lead compounds for the development of anti-metastatic drugs against TNBC. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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23 pages, 3268 KiB  
Article
Isoform-Specific Role of Akt in Oral Squamous Cell Carcinoma
by Nand Kishor Roy, Javadi Monisha, Ganesan Padmavathi, H. Lalhruaitluanga, Nachimuthu Senthil Kumar, Anuj Kumar Singh, Devivasha Bordoloi, Munindra Narayan Baruah, Gazi Naseem Ahmed, Imliwati Longkumar, Frank Arfuso, Alan Prem Kumar and Ajaikumar B. Kunnumakkara
Biomolecules 2019, 9(7), 253; https://doi.org/10.3390/biom9070253 - 27 Jun 2019
Cited by 40 | Viewed by 6028
Abstract
Protein kinase B (Akt) plays a very significant role in various cancers including oral cancer. However, it has three isoforms (Akt1, Akt2, and Akt3) and they perform distinct functions and even play contrasting roles in different cancers. Therefore, it becomes essential to evaluate [...] Read more.
Protein kinase B (Akt) plays a very significant role in various cancers including oral cancer. However, it has three isoforms (Akt1, Akt2, and Akt3) and they perform distinct functions and even play contrasting roles in different cancers. Therefore, it becomes essential to evaluate the isoform-specific role of Akt in oral cancer. In the present study, an attempt has been made to elucidate the isoform-specific role of Akt in oral cancer. The immunohistochemical analysis of oral cancer tissues showed an overexpression of Akt1 and 2 isoforms but not Akt3. Moreover, the dataset of “The Cancer Genome Atlas” for head and neck cancer has suggested the genetic alterations of Akt1 and 2 tend to be associated with the utmost poor clinical outcome in oral cancer. Further, treatment of oral cancer cells with tobacco and its components such as benzo(a)pyrene and nicotine caused increased mRNA levels of Akt1 and 2 isoforms and also enhanced the aggressiveness of oral cancer cells in terms of proliferation, and clonogenic and migration potential. Finally, silencing of Akt1 and 2 isoforms caused decreased cell survival and induced cell cycle arrest at the G2/M phase. Akt1/2 silencing also reduced tobacco-induced aggressiveness by decreasing the clonogenic and migration potential of oral cancer cells. Moreover, silencing of Akt1 and 2 isoforms was found to decrease the expression of proteins regulating cancer cell survival and proliferation such as cyclooxygenase-2, B-cell lymphoma 2 (Bcl-2), cyclin D1, and survivin. Thus, the important role of Akt1 and 2 isoforms have been elucidated in oral cancer with in-depth mechanistic analysis. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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16 pages, 4215 KiB  
Article
Novel Galiellalactone Analogues Can Target STAT3 Phosphorylation and Cause Apoptosis in Triple-Negative Breast Cancer
by Hyejin Ko, Jong Hyun Lee, Hyun Su Kim, Taewoo Kim, Young Taek Han, Young-Ger Suh, Jaemoo Chun, Yeong Shik Kim and Kwang Seok Ahn
Biomolecules 2019, 9(5), 170; https://doi.org/10.3390/biom9050170 - 3 May 2019
Cited by 23 | Viewed by 4304
Abstract
Aberrant activation of signal transducer and activator of transcription 3 (STAT3) has been documented in various malignancies including triple-negative breast cancers (TNBCs). The STAT3 transcription factor can regulate the different important hallmarks of tumor cells, and thus, targeting it can be a potential [...] Read more.
Aberrant activation of signal transducer and activator of transcription 3 (STAT3) has been documented in various malignancies including triple-negative breast cancers (TNBCs). The STAT3 transcription factor can regulate the different important hallmarks of tumor cells, and thus, targeting it can be a potential strategy for treating TNBC, for which only limited therapeutic options are available. In this study, we analyzed the possible effect of (-)-galiellalactone and its novel analogues, SG-1709 and SG-1721, and determined whether these agents exerted their antineoplastic effects by suppressing the STAT3 signaling pathway in TNBC cells. The two analogues, SG-1709 and SG-1721, inhibited both constitutive as well as inducible STAT3 phosphorylation at tyrosine 705 more effectively than (-)-galiellalactone, which indicates that the analogues are more potent STAT3 blockers. Moreover, SG-1721 not only inhibited nuclear translocation and DNA binding of STAT3 but also induced apoptosis, and decreased expression of diverse oncogenic proteins. Interestingly, SG-1721 also exhibited an enhanced apoptotic effect when combined with radiotherapy. Furthermore, in vivo administration of SG-1721 significantly attenuated breast xenograft tumor growth via decreasing levels of p-STAT3. Therefore, SG-1721 may be a promising candidate for further application as a pharmacological agent that can target STAT3 protein in treating TNBC. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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20 pages, 2878 KiB  
Article
Curcuma raktakanda Induces Apoptosis and Suppresses Migration in Cancer Cells: Role of Reactive Oxygen Species
by Shruti Mishra, Sumit Singh Verma, Vipin Rai, Nikee Awasthee, Jayadev S. Arya, Kaustabh K. Maiti and Subash C. Gupta
Biomolecules 2019, 9(4), 159; https://doi.org/10.3390/biom9040159 - 23 Apr 2019
Cited by 28 | Viewed by 4454
Abstract
Although over 100 species of Curcuma are reported, only Curcuma longa is extensively studied. Curcuma raktakanda, a poorly studied species, is most commonly distributed in the Kerala state of India. For the first time, we examined the efficacy of different fractions (acetone, [...] Read more.
Although over 100 species of Curcuma are reported, only Curcuma longa is extensively studied. Curcuma raktakanda, a poorly studied species, is most commonly distributed in the Kerala state of India. For the first time, we examined the efficacy of different fractions (acetone, hexane, and ethyl acetate) of C. raktakanda against glioma, cervical, and breast cancer cell lines. As determined by mitochondrial reductase activity assay, the viability of cancer cells was decreased in a concentration-dependent manner by the three fractions. The half maximal inhibitory concentration (IC-50) values after the treatment of C-6 glioma cells for 48 h was found to be 32.97 µg/mL (acetone extract), 40.63 µg/mL (hexane extract), and 51.65 µg/mL (ethyl acetate extract). Of the three fractions, the acetone fraction was more effective. The long-term colony formation of cancer cells was significantly suppressed by the acetone fraction. Analyses using DAPI (4′,6-diamidino-2-phenylindole) staining, AO/PI (acridine orange/propidium iodide) staining, DNA laddering, and sub-G1 population revealed that the acetone extract induced apoptosis in glioma cells. The extract induced reactive oxygen species generation and suppressed the expression of cell survival proteins. The migration of cancer cells was also suppressed by the acetone extract. The gas chromatography-mass spectrometry (GC-MS) analysis indicated that tetracontane, dotriacontane, hexatriacontane, pentacosane, hexacosane, and eicosane are the major components in the acetone extract. Collectively, the extract from C. raktakanda exhibited anti-carcinogenic activities in cancer cells. We are exploring whether the phytoconstituents, individually, or collectively contribute to the anti-cancer activities of C. raktakanda. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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18 pages, 2574 KiB  
Article
Greensporone A, a Fungal Secondary Metabolite Suppressed Constitutively Activated AKT via ROS Generation and Induced Apoptosis in Leukemic Cell Lines
by Kirti S. Prabhu, Kodappully S. Siveen, Shilpa Kuttikrishnan, Anh Jochebeth, Tayyiba A. Ali, Noor R. Elareer, Ahmad Iskandarani, Abdul Quaiyoom Khan, Maysaloun Merhi, Said Dermime, Tamam El-Elimat, Nicholas H. Oberlies, Feras Q. Alali, Martin Steinhoff and Shahab Uddin
Biomolecules 2019, 9(4), 126; https://doi.org/10.3390/biom9040126 - 29 Mar 2019
Cited by 15 | Viewed by 3911
Abstract
Greensporone A is a fungal secondary metabolite that has exhibited potential in vitro for anti-proliferative activity in vitro. We studied the anticancer activity of greensporone A in a panel of leukemic cell lines. Greensporone A-mediated inhibition of proliferation is found to be associated [...] Read more.
Greensporone A is a fungal secondary metabolite that has exhibited potential in vitro for anti-proliferative activity in vitro. We studied the anticancer activity of greensporone A in a panel of leukemic cell lines. Greensporone A-mediated inhibition of proliferation is found to be associated with the induction of apoptotic cell death. Greensporone A treatment of leukemic cells causes inactivation of constitutively activated AKT and its downstream targets, including members GSK3 and FOXO1, and causes downregulation of antiapoptotic genes such as Inhibitor of Apoptosis (IAPs) and Bcl-2. Furthermore, Bax, a proapoptotic member of the Bcl-2 family, was found to be upregulated in leukemic cell lines treated with greensporone A. Interestingly, gene silencing of AKT using AKT specific siRNA suppressed the expression of Bcl-2 with enhanced expression of Bax. Greensporone A-mediated increase in Bax/Bcl-2 ratio causes permeabilization of the mitochondrial membrane leading to the accumulation of cytochrome c in the cytoplasm. Greensporone A-induced cytochrome c accumulation causes the activation of caspase cascade and cleavage of its effector, poly(ADP-ribose) polymerase (PARP), leading to apoptosis. Greensporone A-mediated apoptosis in leukemic cells occurs through the generation of reactive oxygen species (ROS) due to depletion of glutathione (GSH) levels. Finally, greensporone A potentiated the anticancer activity of imatinib in leukemic cells. In summary, our study showed that greensporone A suppressed the growth of leukemic cells via induction of apoptotic cell death. The apoptotic cell death occurs by inhibition of AKT signaling and activation of the intrinsic apoptotic/caspase pathways. These results raise the possibility that greensporone A could be developed as a therapeutic agent for the treatment of leukemia and other hematological malignancies. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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Review

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28 pages, 13171 KiB  
Review
A Review of the Structure–Activity Relationship of Natural and Synthetic Antimetastatic Compounds
by Su Ki Liew, Sharan Malagobadan, Norhafiza M. Arshad and Noor Hasima Nagoor
Biomolecules 2020, 10(1), 138; https://doi.org/10.3390/biom10010138 - 14 Jan 2020
Cited by 48 | Viewed by 5496
Abstract
There are innumerable anticancer compounds derived from either natural or synthetic origins. Many of these compounds have been further developed through structural modifications to not only inhibit cancer cell growth but also to exert an antimetastatic effect. This is achieved by attaching different [...] Read more.
There are innumerable anticancer compounds derived from either natural or synthetic origins. Many of these compounds have been further developed through structural modifications to not only inhibit cancer cell growth but also to exert an antimetastatic effect. This is achieved by attaching different substituents to generate different structure–activity relationships. This review highlights the effectiveness of different functional groups known to have antimigration and antiproliferation activities, such as fluoro, methoxy, methyl, amino, hydroxy, nitro, bromo, chloro, methylamino, ethoxy, carbonyl, iodo, and trifluoromethyl groups. Additionally, the positioning of these functional groups plays an important role in their anticancer activities, which was evident in one of our studies comparing analogues of a natural compound. Thus, this review suggests future recommendations for the design and development of improved anticancer drugs with higher efficacy. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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17 pages, 1862 KiB  
Review
The Emerging Role of Long Non-Coding RNAs in the Metastasis of Hepatocellular Carcinoma
by Xuejiao Chen, Feng-Ru Tang, Frank Arfuso, Wen-Qi Cai, Zhaowu Ma, Jiyuan Yang and Gautam Sethi
Biomolecules 2020, 10(1), 66; https://doi.org/10.3390/biom10010066 - 31 Dec 2019
Cited by 67 | Viewed by 4191
Abstract
Long non-coding RNAs (lncRNAs) play multifaceted roles in modulating gene expression under both physiological and pathological processes. The dysregulation of lncRNAs has been increasingly linked with many human diseases, including a plethora of cancers. Mounting evidence indicates that lncRNAs are aberrantly expressed in [...] Read more.
Long non-coding RNAs (lncRNAs) play multifaceted roles in modulating gene expression under both physiological and pathological processes. The dysregulation of lncRNAs has been increasingly linked with many human diseases, including a plethora of cancers. Mounting evidence indicates that lncRNAs are aberrantly expressed in hepatocellular carcinoma (HCC) and can regulate HCC progression, as well as metastasis. In this review, we summarize the recent findings on the expanding roles of lncRNAs in modulating various functions of HCC, and elaborate on how can lncRNAs impact HCC metastasis and progression via interacting with chromatin, RNA, and proteins at the epigenetic, transcriptional, and post-transcriptional levels. This mini-review also highlights the current advances regarding the signaling pathways of lncRNAs in HCC metastasis and sheds light on the possible application of lncRNAs for the prevention and treatment of HCC. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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26 pages, 2934 KiB  
Review
Role of Reactive Oxygen Species in Cancer Progression: Molecular Mechanisms and Recent Advancements
by Vaishali Aggarwal, Hardeep Singh Tuli, Ayşegül Varol, Falak Thakral, Mukerrem Betul Yerer, Katrin Sak, Mehmet Varol, Aklank Jain, Md. Asaduzzaman Khan and Gautam Sethi
Biomolecules 2019, 9(11), 735; https://doi.org/10.3390/biom9110735 - 13 Nov 2019
Cited by 745 | Viewed by 20301
Abstract
Reactive oxygen species (ROS) play a pivotal role in biological processes and continuous ROS production in normal cells is controlled by the appropriate regulation between the silver lining of low and high ROS concentration mediated effects. Interestingly, ROS also dynamically influences the tumor [...] Read more.
Reactive oxygen species (ROS) play a pivotal role in biological processes and continuous ROS production in normal cells is controlled by the appropriate regulation between the silver lining of low and high ROS concentration mediated effects. Interestingly, ROS also dynamically influences the tumor microenvironment and is known to initiate cancer angiogenesis, metastasis, and survival at different concentrations. At moderate concentration, ROS activates the cancer cell survival signaling cascade involving mitogen-activated protein kinase/extracellular signal-regulated protein kinases 1/2 (MAPK/ERK1/2), p38, c-Jun N-terminal kinase (JNK), and phosphoinositide-3-kinase/ protein kinase B (PI3K/Akt), which in turn activate the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), matrix metalloproteinases (MMPs), and vascular endothelial growth factor (VEGF). At high concentrations, ROS can cause cancer cell apoptosis. Hence, it critically depends upon the ROS levels, to either augment tumorigenesis or lead to apoptosis. The major issue is targeting the dual actions of ROS effectively with respect to the concentration bias, which needs to be monitored carefully to impede tumor angiogenesis and metastasis for ROS to serve as potential therapeutic targets exogenously/endogenously. Overall, additional research is required to comprehend the potential of ROS as an effective anti-tumor modality and therapeutic target for treating malignancies. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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41 pages, 2410 KiB  
Review
Autophagy Modulators: Mechanistic Aspects and Drug Delivery Systems
by Shima Tavakol, Milad Ashrafizadeh, Shuo Deng, Maryam Azarian, Asghar Abdoli, Mahsa Motavaf, Delaram Poormoghadam, Hashem Khanbabaei, Elham Ghasemipour Afshar, Ali Mandegary, Abbas Pardakhty, Celestial T. Yap, Reza Mohammadinejad and Alan Prem Kumar
Biomolecules 2019, 9(10), 530; https://doi.org/10.3390/biom9100530 - 25 Sep 2019
Cited by 64 | Viewed by 8529
Abstract
Autophagy modulation is considered to be a promising programmed cell death mechanism to prevent and cure a great number of disorders and diseases. The crucial step in designing an effective therapeutic approach is to understand the correct and accurate causes of diseases and [...] Read more.
Autophagy modulation is considered to be a promising programmed cell death mechanism to prevent and cure a great number of disorders and diseases. The crucial step in designing an effective therapeutic approach is to understand the correct and accurate causes of diseases and to understand whether autophagy plays a cytoprotective or cytotoxic/cytostatic role in the progression and prevention of disease. This knowledge will help scientists find approaches to manipulate tumor and pathologic cells in order to enhance cellular sensitivity to therapeutics and treat them. Although some conventional therapeutics suffer from poor solubility, bioavailability and controlled release mechanisms, it appears that novel nanoplatforms overcome these obstacles and have led to the design of a theranostic-controlled drug release system with high solubility and active targeting and stimuli-responsive potentials. In this review, we discuss autophagy modulators-related signaling pathways and some of the drug delivery strategies that have been applied to the field of therapeutic application of autophagy modulators. Moreover, we describe how therapeutics will target various steps of the autophagic machinery. Furthermore, nano drug delivery platforms for autophagy targeting and co-delivery of autophagy modulators with chemotherapeutics/siRNA, are also discussed. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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22 pages, 1299 KiB  
Review
Fisetin and Quercetin: Promising Flavonoids with Chemopreventive Potential
by Dharambir Kashyap, Vivek Kumar Garg, Hardeep Singh Tuli, Mukerrem Betul Yerer, Katrin Sak, Anil Kumar Sharma, Manoj Kumar, Vaishali Aggarwal and Sardul Singh Sandhu
Biomolecules 2019, 9(5), 174; https://doi.org/10.3390/biom9050174 - 6 May 2019
Cited by 183 | Viewed by 17739
Abstract
Despite advancements in healthcare facilities for diagnosis and treatment, cancer remains the leading cause of death worldwide. As prevention is always better than cure, efficient strategies are needed in order to deal with the menace of cancer. The use of phytochemicals as adjuvant [...] Read more.
Despite advancements in healthcare facilities for diagnosis and treatment, cancer remains the leading cause of death worldwide. As prevention is always better than cure, efficient strategies are needed in order to deal with the menace of cancer. The use of phytochemicals as adjuvant chemotherapeutic agents in heterogeneous human carcinomas like breast, colon, lung, ovary, and prostate cancers has shown an upward trend during the last decade or so. Flavonoids are well-known products of plant derivatives that are reportedly documented to be therapeutically active phytochemicals against many diseases encompassing malignancies, inflammatory disorders (cardiovascular disease, neurodegenerative disorder), and oxidative stress. The current review focuses on two key flavonols, fisetin and quercetin, known for their potential pharmacological relevance. Also, efforts have been made to bring together most of the concrete studies pertaining to the bioactive potential of fisetin and quercetin, especially in the modulation of a range of cancer signaling pathways. Further emphasis has also been made to highlight the molecular action of quercetin and fisetin so that one could explore cancer initiation pathways and progression, which could be helpful in designing effective treatment strategies. Full article
(This article belongs to the Special Issue Antitumor Agents from Natural Sources)
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