Onco, Volume 2, Issue 3 (September 2022) – 6 articles

Introduction: In this work, we develop a multi-scale model to calculate corrections to the prescription dose to predict compensation required for the DNA repair mechanism and the repopulation of the cancer cells due to the occurrence of patient scheduling variabilities and the treatment time-gap in fractionation scheme. Methods: A system of multi-scale, time-dependent birth-death Master equations is used to describe stochastic evolution of double-strand breaks (DSBs) formed on DNAs and post-irradiation intra and inter chromosomes end-joining processes in cells, including repair and mis-repair mechanisms in microscopic scale, with an extension appropriate for calculation of tumor control probability (TCP) in macroscopic scale. Variabilities in fractionation time due to systematic shifts in patient’s scheduling and randomness in inter-fractionation treatment time are modeled. For an illustration of the methodology, we focus on prostate cancer. Results: We derive analytical corrections to linear-quadratic radiobiological indices $\alpha$ and $\beta$ as a function of variabilities in treatment time and shifts in patient’s scheduling. We illustrate the dependence of the absolute value of the compensated dose on radio-biological sensitivity, $\alpha /\beta$, DNA repair half-time, $T_{1/2}$, tumor cells repopulation rate, and the time-gaps among treatment fractions due to inter-patient variabilities. At a given tumor size, delays between fractions totaling 24 h over the entire course of treatment, in a typical prostate cancer fractionation scheme, e.g., 81 Gy, 1.8 Gy per fraction and 45 treatment days, require up to 10% compensation dose if the sublethal DNA repair half-time, $T_{1/2}$, spans over 10 h. We show that the contribution of the fast DNA repair mechanisms to the total dose is negligible. Instead, any compensation to the total dose stems from the tumor cell repopulation that may go up to a significant fraction of the original dose for a time gap of up to one week. Conclusions: We recommend implementation of time irregularities in treatment scheduling in the clinic settings to be taken into account. To achieve a clinical endpoint, corrections to the prescription dose must be assessed, in particular, if modern external beam therapy techniques such as IMRT/VMAT are used for the treatment of cancer. Full article

Here, we evaluated transcript-level IL3RA/CD123 expression in mixed lineage leukemia 1 (MLL) gene/KMT2A-rearranged (MLL-R⁺) vs. MLL-R⁻ pediatric AML as well as infant ALL by comparing the archived datasets of the transcriptomes of primary leukemic cells from the corresponding patient populations. Our studies provide unprecedented evidence that IL3RA/CD123 expression exhibits transcript-level amplification in MLL-R⁺ pediatric AML and infant ALL cells. IL3RA was differentially upregulated in MLL-AF10⁺ (2.41-fold higher, p-value = 4.4 × 10⁻⁶) and MLL-AF6⁺ (1.83-fold higher, p-value = 9.9 × 10⁻⁴) but not in MLL-AF9⁺ cases compared to other pediatric AML cases. We also show that IL3RA/CD123 expression is differentially amplified in MLL-AF4⁺ (1.76-fold higher, p-value = 2.1 × 10⁻⁴) as well as MLL-ENL⁺ infant ALL (1.43-fold higher, p-value = 0.055). The upregulated expression of IL3RA/CD123 in MLL-R⁺ pediatric AML and infant ALL suggests that CD123 may be a suitable target for biotherapy in these high-risk leukemias. Full article

Small-cell lung cancer (SCLC) is a high-grade neuroendocrine carcinoma, corresponding to about 15% of lung cancers, occurring predominantly in smokers and associated with a very poor prognosis. Key genetic alterations very frequently observed in SCLC are represented by the loss of TP53 and RB1, due to mutational events or deletions; frequent amplification or overexpression of MYC family genes (MYC, MYCL and MYCN); frequent genetic alterations by mutation/deletion of KMT2D, RB family members p107 (RBL1) and p130 (RBL2), PTEN, NOTCH receptors and CREBBP. The profile of expression of specific transcription factors allowed to differentiate four subtypes of SCLC defined according to levels of ASCL1 (SCLC-A), NEUROD1 (SCLC-N), POUF23 (SCLC-P) or YAP1 (SCLC-Y). A recent study identified the subgroup SCLC-I, characterized by the expression of inflammatory/immune-related genes. Recent studies have characterized at molecular level other lung neuroendocrine tumors, including large cell neuroendocrine cancers (LCNECs) and lung carcinoids. These molecular studies have identified some therapeutic vulnerabilities that can be targeted using specific drugs and some promising biomarkers that can predict the response to this treatment. Furthermore, the introduction of immunotherapy (immune checkpoint blockade) into standard first-line treatment has led to a significant clinical benefit in a limited subset of patients. Full article

The discovery of therapeutically targetable oncogenic driver alterations has led to marked improvements in NSCLC outcomes. Targeted agents have been approved for an expanding list of biomarkers. Consequently, the accurate and timely identification of targetable alterations with diagnostic molecular profiling is crucial. The use of multiplexed tissue assays, such as next-generation sequencing (NGS), has increased significantly. However, significant limitations with tissue NGS remain, such as insufficient tissue, scheduling limitations, the need for repeat biopsies, and long turnaround times. Liquid biopsies, using plasma circulating tumor DNA (ctDNA), have the potential to overcome these issues, with simpler sample processing requirements, greater convenience, and better patient acceptability. In particular, an early liquid biopsy may allow patients access to highly effective therapies faster, allow better symptom control and quality of life, prevent rapid clinical deterioration, and reduce patient anxiety at diagnosis. More broadly, it may also allow for the more cost-effective delivery of healthcare to patients. Full article

Immune checkpoint inhibition (ICI) has emerged as a therapeutic option for acute myeloid leukemia (AML) for patients that suffer from relapsed or high-risk disease, or patients ineligible for standard therapy. We aimed to study ICI as monotherapy and/or combined therapy (with chemotherapy (QT), for AML patients. The PRISMA statement was used. The literature used comprised clinical trials, randomized controlled trials, and systematic reviews published within the last 7 years. The blockade of CTLA-4 presented a 42% of complete remission within AML. Nivolumab in high-risk AML showed a median recurrence-free survival (RFS) of 8.48 months. The same drug on relapsed hematologic malignancies after allogenic transplantation shows a 1-year OS of 56%. The use of prophylaxis post allogenic transplantation cyclophosphamide (PTCy), following checkpoint inhibition, demonstrated different baseline disease and transplantation characteristics when compared to no-PCTy patients, being 32% and 10%, respectively. CTLA-4 blockage was a worthy therapeutic approach in relapsed hematologic malignancies, presenting long-lasting responses. The approach to AML and myelodysplastic syndrome patients with ICI before allogenic hematopoietic stem cell transplantation and the use of a graft-versus-host disease prophylaxis have shown improvement in the transplantation outcomes, and therefore AML treatment. Full article

Fucoxanthinol (FxOH), the main metabolite of the marine carotenoid fucoxanthin, exerts anti-cancer effects. However, fragmentary information is available on the growth-inhibiting effects of FxOH on breast cancer (BC). We investigated the growth-inhibiting effects of FxOH on human BC cells (MCF-7 and MDA-MB-231 cells), and the underlying mechanisms, differently from previous studies, by using comprehensive transcriptome analysis. The molecular mechanisms of FxOH were evaluated using flow cytometry, microarray, Western blotting, and gene knockdown analyses. FxOH (20 μM) significantly induced apoptosis in MCF-7 and MDA-MB-231 cells. Transcriptome analysis revealed that FxOH modulated the following 12 signaling pathways: extracellular matrix (ECM), adhesion, cell cycle, chemokine and cytokine, PI3K/AKT, STAT, TGF-β, MAPK, NF-κB, RAS/Rho, DNA repair, and apoptosis signals. FxOH downregulated the levels of laminin β1, integrin α5, integrin β1, integrin β4, cyclin D1, Rho A, phosphorylated (p)paxillin (Tyr³¹), pSTAT3(Ser⁷²⁷), and pSmad2(Ser^465/467), which play critical roles in the 12 signaling pathways mentioned above. Additionally, FxOH upregulated the levels of pERK1/2(Thr²⁰²/Tyr²⁰⁴) and active form of caspase-3. Integrin β1 or β4 knockdown significantly inhibited the growth of MCF7 and MDA-MB-231 cells. These results suggest that FxOH induces apoptosis in human BC cells through some core signals, especially the ECM–integrins axis, and the downstream of cell cycle, STAT, TGF-β, RAS/Rho, MAPK, and/or DNA repair signals. Full article