Nutritional Epigenetics in Cancer

Epigenetic contribution to the relationship between obesity and cancer

Obesity and cancer are two major health issues all around the world due to their elevated prevalence. Several experimental and epidemiological studies have demonstrated the relationship between obesity and cancer, in which obesity is considered a risk factor for cancer development. The ultimate goal of knowing the epigenetic contribution to the relationship between obesity and cancer is to find the method of intervention or treatment of obesity and cancer. Therefore, providing the most general perspective on epigenetic contribution to the relationship between obesity and cancer is necessary. Obesity is closely related to some common cancers that are currently encountered, including breast, esophagus, liver, kidney, uterus, colorectal, pancreatic, and gallbladder. Obesity has a significant impact that increases the risk of cancer deaths and thereby indirectly affects the choice of treatment. It is estimated that about 4-8% of cancer cases are caused by obesity. In particular, the basic mechanism to understand the relationship between cancer is very complicated and has not been fully understood. This work is aimed at summarizing the current knowledge of the role of epigenetic regulation in the relationship between obesity, and potential applications.

The pharmacoepigenetic paradigm in cancer treatment

Epigenetic modifications, characterized by changes in gene expression without altering the DNA sequence, play a crucial role in the development and progression of cancer by significantly influencing gene activity and cellular function. This insight has led to the development of a novel class of therapeutic agents, known as epigenetic drugs. These drugs, including histone deacetylase inhibitors, histone acetyltransferase inhibitors, histone methyltransferase inhibitors, and DNA methyltransferase inhibitors, aim to modulate gene expression to curb cancer growth by uniquely altering the epigenetic landscape of cancer cells. Ongoing research and clinical trials are rigorously evaluating the efficacy of these drugs, particularly their ability to improve therapeutic outcomes when used in combination with other treatments. Such combination therapies may more effectively target cancer and potentially overcome the challenge of drug resistance, a significant hurdle in cancer therapy. Additionally, the importance of nutrition, inflammation control, and circadian rhythm regulation in modulating drug responses has been increasingly recognized, highlighting their role as critical modifiers of the epigenetic landscape and thereby influencing the effectiveness of pharmacological interventions and patient outcomes. Epigenetic drugs represent a paradigm shift in cancer treatment, offering targeted therapies that promise a more precise approach to treating a wide spectrum of tumors, potentially with fewer side effects compared to traditional chemotherapy. This progress marks a step towards more personalized and precise interventions, leveraging the unique epigenetic profiles of individual tumors to optimize treatment strategies.

ALDH1A3 contributes to tumorigenesis in high-grade serous ovarian cancer by epigenetic modification

High-grade serous ovarian cancer (HGSOC) is the most lethal histotype of ovarian cancer due to its unspecific symptoms in part. ALDH1A3 (aldehyde dehydrogenase 1 family member A3) is a key enzyme for acetyl-CoA production involving aggressive behaviors of cancers. However, ALDH1A3's effects and molecular mechanisms in HGSOC remain to be clarified. Using RNA-seq and publicly available datasets, ALDH1A3 was found to be highly expressed in HGSOC, and associated with poor survival. Knockdown of ALDH1A3 prevented HGSOC tumorigenesis and enhanced cell sensitivity to paclitaxel or cisplatin. ALDH1A3 expression in HGSOC cells was found to be increased by hypoxia, but decreased by HIF-1α inhibitor KC7F2. The dual-luciferase reporter assay showed that the increased transcriptional activity of ALDH1A3 induced by HIF-1α overexpression was reduced by KC7F2. In addition, PITX1 (paired like homeodomain 1) was identified to be inhibited by ALDH1A3 knockdown, and PITX1 depletion inhibited cell proliferation. The mechanistic studies showed that ALDH1A3 knockdown reduced the acetylation of histone 3 lysine 27 (H3K27ac). Treatment of exogenous acetate with NaOAc or inhibition of histone deacetylase with Pracinostat increased H3K27ac and PITX1 levels. CHIP assay demonstrated a significant enrichment of H3K27ac at the PITX1 promoter, and ALDH1A3 knockdown reduced the binding between H3K27ac and PITX1. Taken together, our data suggest that ALDH1A3, transcriptional activated by HIF-1α, promotes tumorigenesis and decreases chemosensitivity by increasing H3K27ac of PITX1 promoter in HGSOC.

Supplement Use and Increased Risks of Cancer: Unveiling the Other Side of the Coin

There is a rising trend in the consumption of dietary supplements, especially among adults, with the purpose of improving health. While marketing campaigns tout the potential health benefits of using dietary supplements, it is critical to evaluate the potential harmful effects associated with these supplements as well. The majority of the scarce research on the potential harmful effects of vitamins focuses on the acute or chronic toxicities associated with the use of dietary supplements. Quality research is still required to further investigate the risks of long-term use of dietary supplements, especially the risk of developing cancers. The present review concentrates on studies that have investigated the association between the risk of developing cancers and associated mortality with the risk of dietary supplements. Such an association has been reported for several vitamins, minerals, and other dietary supplements. Even though several of these studies come with their own shortcomings and critics, they must draw attention to further investigate long-term adverse effects of dietary supplements and advise consumers and healthcare providers to ponder the extensive use of dietary supplements.

Clinical applications of abnormal DNA methylation in chronic myeloid leukemia

DNA methylation, a crucial biochemical process within the human body, fundamentally alters gene expression without modifying the DNA sequence, resulting in stable changes. The changes in DNA methylation are closely related to numerous biological processes including cellular proliferation and differentiation, embryonic development, and the occurrence of immune diseases and tumor. Specifically, abnormal DNA methylation plays a crucial role in the formation, progression, and prognosis of chronic myeloid leukemia (CML). Moreover, DNA methylation offers substantial potential for diagnosing and treating CML. Accordingly, understanding the precise mechanism of DNA methylation, particularly abnormal changes in the methylation of specific genes in CML, can potentially promote the development of novel targeted therapeutic strategies. Such strategies could transform into clinical practice, effectively aiding diagnosis and treatment of CML patients.

Deregulated transcription factors in the emerging cancer hallmarks

Cancer progression is a multifaceted process that entails several stages and demands the persistent expression or activation of transcription factors (TFs) to facilitate growth and survival. TFs are a cluster of proteins with DNA-binding domains that attach to promoter or enhancer DNA strands to start the transcription of genes by collaborating with RNA polymerase and other supporting proteins. They are generally acknowledged as the major regulatory molecules that coordinate biological homeostasis and the appropriate functioning of cellular components, subsequently contributing to human physiology. TFs proteins are crucial for controlling transcription during the embryonic stage and development, and the stability of different cell types depends on how they function in different cell types. The development and progression of cancer cells and tumors might be triggered by any anomaly in transcription factor function. It has long been acknowledged that cancer development is accompanied by the dysregulated activity of TF alterations which might result in faulty gene expression. Recent studies have suggested that dysregulated transcription factors play a major role in developing various human malignancies by altering and rewiring metabolic processes, modifying the immune response, and triggering oncogenic signaling cascades. This review emphasizes the interplay between TFs involved in metabolic and epigenetic reprogramming, evading immune attacks, cellular senescence, and the maintenance of cancer stemness in cancerous cells. The insights presented herein will facilitate the development of innovative therapeutic modalities to tackle the dysregulated transcription factors underlying cancer.

Association analysis of hepatocellular carcinoma-related hub proteins and hub genes

PURPOSE

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. The occurrence and development of HCC are closely related to epigenetic modifications. Epigenetic modifications can regulate gene expression and related functions through DNA methylation. This paper presents an association analysis method of HCC-related hub proteins and hub genes.

EXPERIMENTAL DESIGN

Bioinformatics analysis of HCC-related DNA methylation data is carried out to clarify the molecular mechanism of HCC-related genes and to find hub genes (genes with more connections in the network) by constructing in the gene interaction network. This paper proposes an accurate prediction method of protein-protein interaction (PPI) based on deep learning model DeepSG2PPI. The trained DeepSG2PPI model predicts the interaction relationship between the synthetic proteins regulated by HCC-related genes.

RESULTS

This paper finds that four genes are the intersection of hub genes and hub proteins. The four genes are: FBL, CCNB2, ALDH18A1, and RPLP0. The association of RPLP0 gene with HCC is a new finding of this study. RPLP0 is expected to become a new biomarker for the treatment, diagnosis, and prognosis of HCC. The four proteins corresponding to the four genes are: ENSP00000221801, ENSP00000288207, ENSP00000360268, and ENSP00000449328.

CONCLUSIONS AND CLINICAL RELEVANCE

The association between the hub genes with the hub proteins is analyzed. The mutual verification of the hub genes and the hub proteins can obtain more credible HCC-related genes and proteins, which is helpful for the diagnosis, treatment, and drug development of HCC.

Implication of DNA methylation during lifestyle mediated weight loss

Over the past 50 years, the number of overweight/obese people increased significantly, making obesity a global public health challenge. Apart from rare monogenic forms, obesity is a multifactorial disease, most likely resulting from a concerted interaction of genetic, epigenetic and environmental factors. Although recent studies opened new avenues in elucidating the complex genetics behind obesity, the biological mechanisms contributing to individual's risk to become obese are not yet fully understood. Non-genetic factors such as eating behaviour or physical activity are strong contributing factors for the onset of obesity. These factors may interact with genetic predispositions most likely via epigenetic mechanisms. Epigenome-wide association studies or methylome-wide association studies are measuring DNA methylation at single CpGs across thousands of genes and capture associations to obesity phenotypes such as BMI. However, they only represent a snapshot in the complex biological network and cannot distinguish between causes and consequences. Intervention studies are therefore a suitable method to control for confounding factors and to avoid possible sources of bias. In particular, intervention studies documenting changes in obesity-associated epigenetic markers during lifestyle driven weight loss, make an important contribution to a better understanding of epigenetic reprogramming in obesity. To investigate the impact of lifestyle in obesity state specific DNA methylation, especially concerning the development of new strategies for prevention and individual therapy, we reviewed 19 most recent human intervention studies. In summary, this review highlights the huge potential of targeted interventions to alter disease-associated epigenetic patterns. However, there is an urgent need for further robust and larger studies to identify the specific DNA methylation biomarkers which influence obesity.

Metabolo-epigenetic interplay provides targeted nutritional interventions in chronic diseases and ageing

Epigenetic modifications are chemical modifications that affect gene expression without altering DNA sequences. In particular, epigenetic chemical modifications can occur on histone proteins -mainly acetylation, methylation-, and on DNA and RNA molecules -mainly methylation-. Additional mechanisms, such as RNA-mediated regulation of gene expression and determinants of the genomic architecture can also affect gene expression. Importantly, depending on the cellular context and environment, epigenetic processes can drive developmental programs as well as functional plasticity. However, misbalanced epigenetic regulation can result in disease, particularly in the context of metabolic diseases, cancer, and ageing. Non-communicable chronic diseases (NCCD) and ageing share common features including altered metabolism, systemic meta-inflammation, dysfunctional immune system responses, and oxidative stress, among others. In this scenario, unbalanced diets, such as high sugar and high saturated fatty acids consumption, together with sedentary habits, are risk factors implicated in the development of NCCD and premature ageing. The nutritional and metabolic status of individuals interact with epigenetics at different levels. Thus, it is crucial to understand how we can modulate epigenetic marks through both lifestyle habits and targeted clinical interventions -including fasting mimicking diets, nutraceuticals, and bioactive compounds- which will contribute to restore the metabolic homeostasis in NCCD. Here, we first describe key metabolites from cellular metabolic pathways used as substrates to "write" the epigenetic marks; and cofactors that modulate the activity of the epigenetic enzymes; then, we briefly show how metabolic and epigenetic imbalances may result in disease; and, finally, we show several examples of nutritional interventions - diet based interventions, bioactive compounds, and nutraceuticals- and exercise to counteract epigenetic alterations.