Gene Ontology and Expression Studies of Strigolactone Analogues on a Hepatocellular Carcinoma Cell Line

Natural and Synthetic Anticancer Epidrugs Targeting the Epigenetic Integrator UHRF1

Cancer is one of the leading causes of death worldwide, and its incidence and mortality are increasing each year. Improved therapeutic strategies against cancer have progressed, but remain insufficient to invert this trend. Along with several other risk factors, abnormal genetic and epigenetic regulations play a critical role in the initiation of cellular transformation, as well as tumorigenesis. The epigenetic regulator UHRF1 (ubiquitin-like, containing PHD and RING finger domains 1) is a multidomain protein with oncogenic abilities overexpressed in most cancers. Through the coordination of its multiple domains and other epigenetic key players, UHRF1 regulates DNA methylation and histone modifications. This well-coordinated dialogue leads to the silencing of tumor-suppressor genes (TSGs) and facilitates tumor cells' resistance toward anticancer drugs, ultimately promoting apoptosis escape and uncontrolled proliferation. Several studies have shown that the downregulation of UHRF1 with natural compounds in tumor cells induces the reactivation of various TSGs, inhibits cell growth, and promotes apoptosis. In this review, we discuss the underlying mechanisms and the potential of various natural and synthetic compounds that can inhibit/minimize UHRF1's oncogenic activities and/or its expression.

Network pharmacological evaluation of strigolactones efficacy as potential inhibitors against therapeutic targets of hepatocellular carcinoma

PURPOSE

Hepatocellular carcinoma (HCC) is the uncontrolled growth of hepatocytes which results in nearly 5 million deaths worldwide. Specific strategies have been developed to treat HCC, including surgery, chemotherapy and radiotherapy. But, the effective disease dealing requires synergistic collaboration with other approaches, which often results in moderate to severe side effects during and after the treatment period. Therefore, the focus is now shifting to explore and retrieve those plant-based products that could be utilized to treat HCC with maximum efficacy without causing any side effects. Strigolactones (SL) are compounds of plant origin derived from Striga lutea responsible for controlling the branching pattern of stem and have reported anti-cancerous activity by promoting apoptosis at micromolar concentrations. However, little work has been done concerning determining the pharmacogenomic effect of strigolactones on HCC.

METHODS

Current work focuses on comparing therapeutic efficiencies of SL analogs against core targets of HCC using network pharmacology approach, pharmacokinetics analysis, gene ontogeny, functional enrichment analysis, molecular docking and Molecular Dynamics simulation.

RESULTS

Drug-target prediction and functional enrichment analysis showed that HDAC1 and HDAC2 are the core proteins involved in hepatocellular carcinoma that strigolactone analogs can target. Consequently, results from molecular docking and MD simulation analyses report that among all the SL analogs strigol, epistrigol and nijmegen1 can turn out to be most effective in downregulating the expression of HDAC1, HDAC2 and CYP19A.

CONCLUSION

Strigol, epistrigol and nijmegen1 could be used as potential inhibitors against HCC and can be further validated through in vitro/in vivo studies.

Transcriptomic analysis links hepatocellular carcinoma (HCC) in HZE ion irradiated mice to a human HCC subtype with favorable outcomes

High-charge, high-energy ion particle (HZE) radiations are extraterrestrial in origin and characterized by high linear energy transfer (high-LET), which causes more severe cell damage than low-LET radiations like γ-rays or photons. High-LET radiation poses potential cancer risks for astronauts on deep space missions, but the studies of its carcinogenic effects have relied heavily on animal models. It remains uncertain whether such data are applicable to human disease. Here, we used genomics approaches to directly compare high-LET radiation-induced, low-LET radiation-induced and spontaneous hepatocellular carcinoma (HCC) in mice with a human HCC cohort from The Cancer Genome Atlas (TCGA). We identified common molecular pathways between mouse and human HCC and discovered a subset of orthologous genes (mR-HCC) that associated high-LET radiation-induced mouse HCC with a subgroup (mrHCC2) of the TCGA cohort. The mrHCC2 TCGA cohort was more enriched with tumor-suppressing immune cells and showed a better prognostic outcome than other patient subgroups.

Thymoquinone and Difluoromethylornithine (DFMO) Synergistically Induce Apoptosis of Human Acute T Lymphoblastic Leukemia Jurkat Cells Through the Modulation of Epigenetic Pathways

Thymoquinone (TQ), a natural anticancer agent exerts cytotoxic effects on several tumors by targeting multiple pathways, including apoptosis. Difluoromethylornithine (DFMO), an irreversible inhibitor of the ornithine decarboxylase (ODC) enzyme, has shown promising inhibitory activities in many cancers including leukemia by decreasing the biosynthesis of the intracellular polyamines. The present study aimed to investigate the combinatorial cytotoxic effects of TQ and DFMO on human acute T lymphoblastic leukemia Jurkat cells and to determine the underlying mechanisms. Here, we show that the combination of DFMO and TQ significantly reduced cell viability and resulted in significant synergistic effects on apoptosis when compared to either DFMO or TQ alone. RNA-sequencing showed that many key epigenetic players including Ubiquitin-like containing PHD and Ring finger 1 (UHRF1) and its 2 partners DNA methyltransferase 1 (DNMT1) and histone deacetylase 1 (HDAC1) were down-regulated in DFMO-treated Jurkat cells. The combination of DFMO and TQ dramatically decreased the expression of UHRF1, DNMT1 and HDAC1 genes compared to either DFMO or TQ alone. UHRF1 knockdown led to a decrease in Jurkat cell viability. In conclusion, these results suggest that the combination of DFMO and TQ could be a promising new strategy for the treatment of human acute T lymphoblastic leukemia by targeting the epigenetic code.