Effect of Sulforaphane and 5-Aza-2'-Deoxycytidine on Melanoma Cell Growth

Harnessing Sulforaphane Potential as a Chemosensitizing Agent: A Comprehensive Review

Recent advances in oncological research have highlighted the potential of naturally derived compounds in cancer prevention and treatment. Notably, sulforaphane (SFN), an isothiocyanate derived from cruciferous vegetables including broccoli and cabbage, has exhibited potent chemosensitizing capabilities across diverse cancer types of bone, brain, breast, lung, skin, etc. Chemosensitization refers to the enhancement of cancer cell sensitivity to chemotherapy agents, counteracting the chemoresistance often developed by tumor cells. Mechanistically, SFN orchestrates this sensitization by modulating an array of cellular signaling pathways (e.g., Akt/mTOR, NF-κB, Wnt/β-catenin), and regulating the expression and activity of pivotal genes, proteins, and enzymes (e.g., p53, p21, survivin, Bcl-2, caspases). When combined with conventional chemotherapeutic agents, SFN synergistically inhibits cancer cell proliferation, invasion, migration, and metastasis while potentiating drug-induced apoptosis. This positions SFN as a potential adjunct in cancer therapy to augment the efficacy of standard treatments. Ongoing preclinical and clinical investigations aim to further delineate the therapeutic potential of SFN in oncology. This review illuminates the multifaceted role of this phytochemical, emphasizing its potential to enhance the therapeutic efficacy of anti-cancer agents, suggesting its prospective contributions to cancer chemosensitization and management.

Natural Bioactive Compounds Targeting Epigenetic Pathways in Cancer: A Review on Alkaloids, Terpenoids, Quinones, and Isothiocyanates

Cancer is one of the most complex and systemic diseases affecting the health of mankind, causing major deaths with a significant increase. This pathology is caused by several risk factors, of which genetic disturbances constitute the major elements, which not only initiate tumor transformation but also epigenetic disturbances which are linked to it and which can induce transcriptional instability. Indeed, the involvement of epigenetic disturbances in cancer has been the subject of correlations today, in addition to the use of drugs that operate specifically on different epigenetic pathways. Natural molecules, especially those isolated from medicinal plants, have shown anticancer effects linked to mechanisms of action. The objective of this review is to explore the anticancer effects of alkaloids, terpenoids, quinones, and isothiocyanates.

Progress and promises of epigenetic drugs and epigenetic diets in cancer prevention and therapy: A clinical update

Epigenetic modifications are heritable yet reversible, essential for normal physiological functions and biological development. Aberrant epigenetic modifications, including DNA methylation, histone modification, and non-coding RNA (ncRNA)-mediated gene regulation play a crucial role in cancer progression. In cellular reprogramming, irregular epigenomic modulations alter cell signaling pathways and the expression of tumor suppressor genes and oncogenes, resulting in cancer growth and metastasis. Therefore, alteration of epigenetic-status in cancer cells can be used as a potential target for cancer therapy. Several synthetic epigenetic inhibitors (epi-drugs) and natural epigenetic modulatory bioactives (epi-diets) have been shown to have the potential to alter the aberrant epigenetic status and inhibit cancer progression. Further, the use of combinatorial approaches with epigenetic drugs and diets has brought promising outcomes in cancer prevention and therapy. In this article, we have summarized the epigenetic modulatory activities of epi-drugs, epi-diets, and their combination against various cancers. We have also compiled the preclinical and clinical status of these epigenetic modulators in different cancers.

Epigenetic Control of Cdkn2a.Arf Protects Tumor-Infiltrating Lymphocytes from Metabolic Exhaustion

T-cell exhaustion in cancer is linked to poor clinical outcomes, where evidence suggests T-cell metabolic changes precede functional exhaustion. Direct competition between tumor-infiltrating lymphocytes (TIL) and cancer cells for metabolic resources often renders T cells dysfunctional. Environmental stress produces epigenome remodeling events within TIL resulting from loss of the histone methyltransferase EZH2. Here, we report an epigenetic mechanism contributing to the development of metabolic exhaustion in TIL. A multiomics approach revealed a Cdkn2a.Arf-mediated, p53-independent mechanism by which EZH2 inhibition leads to mitochondrial dysfunction and the resultant exhaustion. Reprogramming T cells to express a gain-of-function EZH2 mutant resulted in an enhanced ability of T cells to inhibit tumor growth in vitro and in vivo. Our data suggest that manipulation of T-cell EZH2 within the context of cellular therapies may yield lymphocytes that are able to withstand harsh tumor metabolic environments and collateral pharmacologic insults. SIGNIFICANCE: These findings demonstrate that manipulation of T-cell EZH2 in cellular therapies may yield cellular products able to withstand solid tumor metabolic-deficient environments. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/21/4707/F1.large.jpg.

The Impact of Natural Dietary Compounds and Food-Borne Mycotoxins on DNA Methylation and Cancer

Cancer initiation and progression is an accumulation of genetic and epigenetic modifications. DNA methylation is a common epigenetic modification that regulates gene expression, and aberrant DNA methylation patterns are considered a hallmark of cancer. The human diet is a source of micronutrients, bioactive molecules, and mycotoxins that have the ability to alter DNA methylation patterns and are thus a contributing factor for both the prevention and onset of cancer. Micronutrients such as betaine, choline, folate, and methionine serve as cofactors or methyl donors for one-carbon metabolism and other DNA methylation reactions. Dietary bioactive compounds such as curcumin, epigallocatechin-3-gallate, genistein, quercetin, resveratrol, and sulforaphane reactivate essential tumor suppressor genes by reversing aberrant DNA methylation patterns, and therefore, they have shown potential against various cancers. In contrast, fungi-contaminated agricultural foods are a source of potent mycotoxins that induce carcinogenesis. In this review, we summarize the existing literature on dietary micronutrients, bioactive compounds, and food-borne mycotoxins that affect DNA methylation patterns and identify their potential in the onset and treatment of cancer.

Natural Compounds as New Cancer Treatments

Cancer is still a global challenge worldwide with a high impact not only on human health, causing morbidity and mortality, but also on economics [...].

Effect of Sulforaphane and 5-Aza-2'-Deoxycytidine on Melanoma Cell Growth

Background: UV exposure-induced oxidative stress is implicated as a driving mechanism for melanoma. Increased oxidative stress results in DNA damage and epigenetic dysregulation. Accordingly, we explored whether a low dose of the antioxidant sulforaphane (SFN) in combination with the epigenetic drug 5-aza-2’-deoxycytidine (DAC) could slow melanoma cell growth. SFN is a natural bioactivated product of the cruciferous family, while DAC is a DNA methyltransferase inhibitor. Methods: Melanoma cell growth characteristics, gene transcription profiles, and histone epigenetic modifications were measured after single and combination treatments with SFN and DAC. Results: We detected melanoma cell growth inhibition and specific changes in gene expression profiles upon combinational treatments with SFN and DAC, while no significant alterations in histone epigenetic modifications were observed. Dysregulated gene transcription of a key immunoregulator cytokine—C-C motif ligand 5 (CCL-5)—was validated. Conclusions: These results indicate a potential combinatorial effect of a dietary antioxidant and an FDA-approved epigenetic drug in controlling melanoma cell growth.