The role of DNA methylation in ageing and cancer

Colorectal cancer microbiome programs DNA methylation of host cells by affecting methyl donor metabolism

BACKGROUND

Colorectal cancer (CRC) arises from complex interactions between host and environment, which include the gut and tissue microbiome. It is hypothesized that epigenetic regulation by gut microbiota is a fundamental interface by which commensal microbes dynamically influence intestinal biology. The aim of this study is to explore the interplay between gut and tissue microbiota and host DNA methylation in CRC.

METHODS

Metagenomic sequencing of fecal samples was performed on matched CRC patients (n = 18) and healthy controls (n = 18). Additionally, tissue microbiome was profiled with 16S rRNA gene sequencing on tumor (n = 24) and tumor-adjacent normal (n = 24) tissues of CRC patients, while host DNA methylation was assessed through whole-genome bisulfite sequencing (WGBS) in a subset of 13 individuals.

RESULTS

Our analysis revealed substantial alterations in the DNA methylome of CRC tissues compared to adjacent normal tissues. An extensive meta-analysis, incorporating publicly available and in-house data, identified significant shifts in microbial-derived methyl donor-related pathways between tumor and adjacent normal tissues. Of note, we observed a pronounced enrichment of microbial-associated CpGs within the promoter regions of genes in adjacent normal tissues, a phenomenon notably absent in tumor tissues. Furthermore, we established consistent and recurring associations between methylation patterns of tumor-related genes and specific bacterial taxa.

CONCLUSIONS

This study emphasizes the pivotal role of the gut microbiota and pathogenic bacteria in dynamically shaping DNA methylation patterns, impacting physiological homeostasis, and contributing to CRC tumorigenesis. These findings provide valuable insights into the intricate host-environment interactions in CRC development and offer potential avenues for therapeutic interventions in this disease.

GametesOmics: A Comprehensive Multi-omics Database for Exploring the Gametogenesis in Humans and Mice

Gametogenesis plays an important role in the reproduction and evolution of species. The transcriptomic and epigenetic alterations in this process can influence the reproductive capacity, fertilization, and embryonic development. The rapidly increasing single-cell studies have provided valuable multi-omics resources. However, data from different layers and sequencing platforms have not been uniformed and integrated, which greatly limits their use for exploring the molecular mechanisms that underlie oogenesis and spermatogenesis. Here, we develop GametesOmics, a comprehensive database that integrates the data of gene expression, DNA methylation, and chromatin accessibility during oogenesis and spermatogenesis in humans and mice. GametesOmics provides a user-friendly website and various tools, including Search and Advanced Search for querying the expression and epigenetic modification(s) of each gene; Tools with Differentially expressed gene (DEG) analysis for identifying DEGs, Correlation analysis for demonstrating the genetic and epigenetic changes, Visualization for displaying single-cell clusters and screening marker genes as well as master transcription factors (TFs), and MethylView for studying the genomic distribution of epigenetic modifications. GametesOmics also provides Genome Browser and Ortholog for tracking and comparing gene expression, DNA methylation, and chromatin accessibility between humans and mice. GametesOmics offers a comprehensive resource for biologists and clinicians to decipher the cell fate transition in germ cell development, and can be accessed at http://gametesomics.cn/.

Elevated serum homocysteine levels associated with poor recurrence-free and overall survival in patients with colorectal cancer

This study aimed to evaluate the significance of homocysteine (HCY) levels in predicting recurrence-free survival (RFS) and overall survival (OS) in colorectal cancer (CRC) patients. This retrospective study involved 1272 CRC patients. The risk of mortality increased with increasing HCY levels in CRC patients. The optimal HCY cutoff value in CRC patients was 15.2 μmol/L. The RFS (45.8% vs. 60.5%, p < 0.001) and OS (48.2% vs. 63.2%, p < 0.001) of patients with high HCY levels were significantly lower than those of patients with low HCY levels. Patients with high HCY levels were older, male, had large tumours, high carcinoembryonic antigen (CEA) levels, and long hospital stays, and incurred high hospitalisation costs. Multivariate analysis showed that when HCY levels exceeded 15.2 μmol/L, the risk of adverse RFS and OS increased by 55.7% and 61.4%, respectively. Subgroup analysis showed that HCY levels could supplement CEA levels and pathological staging. We constructed HCY-based prognostic nomograms, which demonstrated feasible discrimination and calibration values better than the traditional tumour, node, metastasis staging system for predicting RFS and OS. Elevated serum HCY levels were strongly associated with poor RFS and OS in CRC patients. HCY-based prognostic models are effective tools for a comprehensive evaluation of prognosis.

Pan-cancer analysis reveals correlation between RAB3B expression and tumor heterogeneity, immune microenvironment, and prognosis in multiple cancers

RAB3B is essential for the transportation and secretion within cells. Its increased expression is linked to the development and progression of various malignancies. However, understanding of RAB3B's involvement in carcinogenesis is mostly limited to specific cancer subtypes. Hence, exploring RAB3B's regulatory roles and molecular mechanisms through comprehensive cancer datasets might offer innovative approaches for managing clinical cancer. To examine the potential involvement of RAB3B in the development of cancer, we analyzed data from various sources including The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression Project (GTEx), cBioPortal, HPA, UALCAN, and tissue microarray (TAM). Using bioinformatics techniques, we examined the correlation between RAB3B expression and prognosis, tumor heterogeneity, methylation modifications, and immune microenvironment across different cancer types. Our findings indicate that elevated RAB3B expression can independently predict prognosis in many tumors and has moderate accuracy for diagnosing most cancers. In most cancer types, we identified RAB3B mutations that showed a significant correlation with tumor mutational burden (TMB), mutant-allele tumor heterogeneity (MATH), and microsatellite instability (MSI). Abnormal DNA methylation patterns were also observed in most cancers compared to normal tissues. Additionally, we found significant correlations between RAB3B expression, immune cell infiltration, and immune scores across various cancers. Through pan-cancer analysis, we observed significant differences in RAB3B expression levels between tumors and normal tissues, making it a potential primary factor for cancer diagnosis and prognosis. The IHC results revealed that the expression of RAB3B in six types of tumors was consistent with the results of the pan-cancer analysis of the database. Furthermore, RAB3B showed potential associations with tumor heterogeneity and immunity. Thus, RAB3B can be utilized as an auxiliary diagnostic marker for early tumor detection and a prognostic biomarker for various tumor types.

Fresh Insights Into SLC25A26: Potential New Therapeutic Target for Cancers: A Review

SLC25A26 is the only known human mitochondrial S-adenosylmethionine carrier encoding gene. Recent studies have shown that SLC25A26 is abnormally expressed in some cancers, such as cervical cancer, low-grade glioma, non-small cell lung cancer, and liver cancer, which suggests SLC25A26 can affect the occurrence and development of some cancers. This article in brief briefly reviewed mitochondrial S-adenosylmethionine carrier in different species and its encoding gene, focused on the association of SLC25A26 aberrant expression and some cancers as well as potential mechanisms, summarized its potential for cancer prognosis, and characteristics of mitochondrial diseases caused by SLC25A26 mutation. Finally, we provide a brief expectation that needs to be further investigated. We speculate that SLC25A26 will be a potential new therapeutic target for some cancers.

Vascular dementia: From pathobiology to emerging perspectives

Vascular dementia (VaD) is the second most common type of dementia. VaD is synonymous with ageing, and its symptoms place a significant burden on the health and wellbeing of older people. Despite the identification of a substantial number of risk factors for VaD, the pathological mechanisms underpinning this disease remain to be fully elucidated. Consequently, a biogerontological imperative exists to highlight the modifiable lifestyle factors which can mitigate against the risk of developing VaD. This review will critically examine some of the factors which have been revealed to modulate VaD risk. The survey commences by providing an overview of the putative mechanisms which are associated with the pathobiology of VaD. Next, the factors which influence the risk of developing VaD are examined. Finally, emerging treatment avenues including epigenetics, the gut microbiome, and pro-longevity pharmaceuticals are discussed. By drawing this key evidence together, it is our hope that it can be used to inform future experimental investigations in this field.

Epigenetic Reprogramming Drives Epithelial Disruption in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) remains a major public health challenge that contributes greatly to mortality and morbidity worldwide. Although it has long been recognized that the epithelium is altered in COPD, there has been little focus on targeting it to modify the disease course. Therefore, mechanisms that disrupt epithelial cell function in patients with COPD are poorly understood. In this study, we sought to determine whether epigenetic reprogramming of the cell-cell adhesion molecule E-cadherin, encoded by the CDH1 gene, disrupts epithelial integrity. By reducing these epigenetic marks, we can restore epithelial integrity and rescue alveolar airspace destruction. We used differentiated normal and COPD-derived primary human airway epithelial cells, genetically manipulated mouse tracheal epithelial cells, and mouse and human precision-cut lung slices to assess the effects of epigenetic reprogramming. We show that the loss of CDH1 in COPD is due to increased DNA methylation site at the CDH1 enhancer D through the downregulation of the ten-eleven translocase methylcytosine dioxygenase (TET) enzyme TET1. Increased DNA methylation at the enhancer D region decreases the enrichment of RNA polymerase II binding. Remarkably, treatment of human precision-cut slices derived from patients with COPD with the DNA demethylation agent 5-aza-2'-deoxycytidine decreased cell damage and reduced air space enlargement in the diseased tissue. Here, we present a novel mechanism that targets epigenetic modifications to reverse the tissue remodeling in human COPD lungs and serves as a proof of concept for developing a disease-modifying target.

Comprehensive analysis indicated that NDE1 is a potential biomarker for pan-cancer and promotes bladder cancer progression

BACKGROUND

The nuclear distribution E homologue 1 (NDE1) is a crucial dynein binding partner. The NDE1 protein has the potential to disrupt the normal functioning of centrosomes, leading to a compromised ability to generate spindles and ensure precise separation of chromosomes during cell division. The potential consequences of this phenomenon include genomic instability, malignant transformation and the proliferation of neoplastic growths. However, studies examining the connection between NDE1 and cancer is still very rare.

METHODS

The expression level, prognostic impact, gene change, DNA methylation, protein interaction, mRNA m6A modification, ceRNA network, associated gene and function enrichment, and immune-related effects of NDE1 in pan-cancer were examined using a range of online analytic tools and the R software package. The CCK-8 test, transwell assay, scratch assay and colony formation assay were used to confirm the effects of NDE1 on the proliferation, invasion and metastasis of bladder cancer cells.

RESULTS

Numerous tumour types have elevated NDE1, which is linked to a bad prognosis. NDE1 is an excellent diagnostic tool for many different types of cancer. Numerous malignancies have been linked to genetic changes in NDE1. NDE1 was connected to TMB, MSI, several immunological checkpoint genes and immune cell infiltration. NDE1 is linked to a number of immunological subtypes. NDE1 could affect how well immunotherapy works to treat different types of cancer. NDE1 was mostly associated with cell cycle, chromosomal segregation, DNA replication and mitotic segregation, according to GO and KEGG analyses. NDE1 physically binds to PAFAH1B1 and DCTN1, respectively. The proliferation, invasion and metastasis of bladder cancer cells may be prevented by NDE1 knockdown. Furthermore, knockdown of NDE1 promoted the apoptosis of bladder cancer cells.

CONCLUSION

High expression of NDE1 is present in a variety of tumours, which is linked to a bad prognosis for cancer. Knockdown of NDE1 inhibited the proliferation, invasion and metastasis of bladder cancer cells, and promoted the apoptosis. For a number of malignancies, NDE1 may be a biomarker for immunotherapy and prognosis.

First principles studies on the adsorption of rare base-pairs on the surface of B/N atom doped γ-graphyne

Rare base-pairs consists of guanine (G) paired with rare bases, such as 5-methylcytosine (5-meCyt), 5-hydroxymethylcytosine (5-hmCyt), 5-carboxylcytosine (5-caCyt), and 5-formylcytosine (5-fCyt), have become the focus of epigenetic research because they can be used as markers to detect some chronic diseases and cancers. However, the correlation detection of these rare base-pairs is limited, which in turn limits the development of diagnostic tests and devices. Herein, the interaction of rare base-pairs adsorbed on pure and B/N-doped γ-graphyne (γ-GY) nanosheets was explored using the density functional theory. The calculated adsorption energy showed that the system of rare base-pairs on B-doped γ-GY is more stable than that on pure γ-GY or N-doped γ-GY. Translocation time values indicate that rare base-pairs can be successfully distinguished as the difference in their translocation times is very large for pure and B/N-doped γ-GY nanosheets. Meanwhile, sensing response values illustrated that pure and B-doped γ-GY are the best for G-5-hmCyt adsorption, while the N-doped γ-GY is the best for G-Cyt adsorption. The findings indicate that translocation times and sensing response can be used as detection indexes for pure and B/N doped γ-GY, which will provide a new way for experimental scientists to develop the biosensor components.

Possible Molecular Mechanisms of Hypertension Induced by Sleep Apnea Syndrome/Intermittent Hypoxia

Intermittent hypoxia (IH) is a central characteristic of sleep apnea syndrome (SAS), and it subjects cells in the body to repetitive apnea, chronic hypoxia, oxygen desaturation, and hypercapnia. Since SAS is linked to various serious cardiovascular complications, especially hypertension, many studies have been conducted to elucidate the mechanism of hypertension induced by SAS/IH. Hypertension in SAS is associated with numerous cardiovascular disorders. As hypertension is the most common complication of SAS, cell and animal models to study SAS/IH have developed and provided lots of hints for elucidating the molecular mechanisms of hypertension induced by IH. However, the detailed mechanisms are obscure and under investigation. This review outlines the molecular mechanisms of hypertension in IH, which include the regulation systems of reactive oxygen species (ROS) that activate the renin-angiotensin system (RAS) and catecholamine biosynthesis in the sympathetic nervous system, resulting in hypertension. And hypoxia-inducible factors (HIFs), Endotheline 1 (ET-1), and inflammatory factors are also mentioned. In addition, we will discuss the influences of SAS/IH in cardiovascular dysfunction and the relationship of microRNA (miRNA)s to regulate the key molecules in each mechanism, which has become more apparent in recent years. These findings provide insight into the pathogenesis of SAS and help in the development of future treatments.

A prognostic model based on DNA methylation-related gene expression for predicting overall survival in hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) continues to increase in morbidity and mortality among all types of cancer. DNA methylation, an important epigenetic modification, is associated with cancer occurrence and progression. The objective of this study was to establish a model based on DNA methylation risk scores for identifying new potential therapeutic targets in HCC and preventing cancer progression.

Methods

Transcriptomic, clinical, and DNA methylation data on 374 tumor tissues and 50 adjacent normal tissues were downloaded from The Cancer Genome Atlas-Liver Hepatocellular Carcinoma database. The gene expression profiles of the GSE54236 liver cancer dataset, which contains data on 161 liver tissue samples, were obtained from the Gene Expression Omnibus database. We analyzed the relationship between DNA methylation and gene expression levels after identifying the differentially methylated and expressed genes. Then, we developed and validated a risk score model based on the DNA methylation-driven genes. A tissue array consisting of 30 human hepatocellular carcinoma samples and adjacent normal tissues was used to assess the protein and mRNA expression levels of the marker genes by immunohistochemistry and qRT-PCR, respectively.

Results

Three methylation-related differential genes were identified in our study: GLS, MEX3B, and GNA14. The results revealed that their DNA methylation levels were negatively correlated with local gene expression regulation. The gene methylation levels correlated strongly with the prognosis of patients with liver cancer. This was confirmed by qRT-PCR and immunohistochemical verification of the expression of these genes or proteins in tumors and adjacent tissues. These results revealed the relationship between the level of relevant gene methylation and the prognosis of patients with liver cancer as well as the underlying cellular and biological mechanisms. This allows our gene signature to provide more accurate and appropriate predictions for clinical applications.

Conclusion

Through bioinformatics analysis and experimental validation, we obtained three DNA methylation marker: GLS, MEX3B, and GNA14. This helps to predict the prognosis and may be a potential therapeutic target for HCC patients.

Epigenetic Regulation in Urothelial Carcinoma

Urothelial carcinoma (UC) is a common malignancy that remains a clinical challenge: Non-muscle-invasive urothelial carcinoma (NMIUC) has a high rate of recurrence and risk of progression, while muscle-invasive urothelial carcinoma (MIUC) has a high mortality. Although some new treatments, such as immunotherapies, have shown potential effects on some patients, most cases of advanced UC remain incurable. While treatments based on epigenetic mechanisms, whether combined with traditional platinum-based chemotherapy or emerging immunotherapy, show therapeutic advantages. With the advancement of sequencing and bioinformatics, the study of epigenomics, containing DNA methylation, histone modifications, chromatin remodeling, and non-coding RNA, is increasingly linked with the occurrence and progression of UC. Since the epigenetics of UC is a constantly developing field of medicine, this review aims to summarize the latest research on epigenetic regulation of UC, generalize the mechanism of epigenetics in UC, and reveal the potential epigenetic therapies in the clinical setting, in order to provide some new clues on the discovery of new drugs based on the epigenetics.

A new mathematical model of folate homeostasis in E. coli highlights the potential importance of the folinic acid futile cycle in cell growth

Folate (vitamin B9) plays a central role in one-carbon metabolism in prokaryotes and eukaryotes. This pathway mediates the transfer of one-carbon units, playing a crucial role in nucleotide synthesis, methylation, and amino acid homeostasis. The folinic acid futile cycle adds a layer of intrigue to this pathway, due to its associations with metabolism, cell growth, and dormancy. It also introduces additional complexity to folate metabolism. A logical way to deal with such complexity is to examine it by using mathematical modelling. This work describes the construction and analysis of a model of folate metabolism, which includes the folinic acid futile cycle. This model was tested under three in silico growth conditions. Model simulations revealed: 1) the folate cycle behaved as a stable biochemical system in three growth states (slow, standard, and rapid); 2) the initial concentration of serine had the greatest impact on metabolite concentrations; 3) 5-formyltetrahydrofolate cyclo-ligase (5-FCL) activity had a significant impact on the levels of the 7 products that carry the one-carbon donated from folates, and the redox couple NADP/NADPH; this was particularly evident in the rapid growth state; 4) 5-FCL may be vital to the survival of the cells by maintaining low levels of homocysteine, as high levels can induce toxicity; and 5) the antifolate therapeutic trimethoprim had a greater impact on folate metabolism with higher nutrient availability. These results highlight the important role of 5-FCL in intracellular folate homeostasis and mass generation under different metabolic scenarios.

DNA methylation regulates pancreatic gene expression and links maternal high-fat diet to the offspring glucose metabolism

Maternal high-fat diet (HFD) is related to an increased risk of glucose metabolism disorders throughout the whole life of offspring. The pancreas is a glucose homeostasis regulator. Accumulating evidence has revealed that maternal HFD affects offspring pancreas structure and function. However, the potential mechanism remains unclear. In this study, the mouse dam was fed with HFD or control diet (CD) during prepregnancy, pregnancy and lactation. The pancreatic insulin secretion function and islet genome methylome of offspring were analyzed. Pancreatic islet specific gene methylation was detected by using MeDIP qPCR. The results showed that body weight, blood glucose after oral glucose loads, fasting serum insulin, and HOMA-IR index values were significantly higher in male 12-week-old offspring from HFD dams than in the offspring from CD dams. Maternal HFD induced insulin secretion defects in male offspring. Compared with that in maternal CD group, methylation of the Abcc8 and Kcnj11 genes was increased in maternal HFD group in male offspring pancreatic islets. Furthermore, the expression levels of Abcc8 and Kcnj11 were downregulated by intrauterine exposure to a maternal HFD. In summary, maternal HFD results in a long-term functional disorder of the pancreas that is involved in insulin secretion-related gene DNA hypermethylation.

Molecular Expression and Prognostic Implications of Krüppel-Like Factor 3 (KLF3) in Clear Cell Renal Cell Carcinoma

A major subtype of renal cancer is clear cell renal cell carcinoma (ccRCC). Krüppel-like factor 3 (KLF3) dysfunction is also revealed leading to poor prognosis in multiple cancer types. However, dysregulation and molecular dynamics of KLF3 underlying ccRCC progression still remains elusive. Here KLF3 gene and protein expressions in ccRCC were explored using data cohorts from The Cancer Genome Atlas (TCGA), Human Protein Atlas (HPA), Clinical Proteomic Tumor Analysis Consortium (CPTAC) and verified them in our patient cohort. Correlations of KLF3 expression with clinicopathological features, epigenetic modification, and immune microenvironment characteristics were further investigated. KLF3 was significantly down-regulated expressed in ccRCC tissues compared to adjacent normal controls. Adverse pathological parameters and poor prognosis were associated with lower expression of KLF3. Mechanically, KLF3 regulation was mainly attributed to CpG island methylation. KLF3-high expression subgroup was significantly enriched in cell signaling pathways most associated with EMT markers, angiogenesis, inflammatory response, apoptosis, TGF-β, degradation of ECM, G2M checkpoint, and PI3K-AKT-mTOR. Based on GDSC database, KLF3 upregulation was identified to be associated with higher sensitivities towards PI3K-Akt-mTOR pathway inhibitors such as PI-103, PIK-93, and OSI-027. In addition, patients with down-regulated KLF3 expressions were found more sensitive towards Trametinib, Cetuximab, and Erlotinib. Collectively, our findings suggest that KLF3 may act as a suitable biomarker for prognosis prediction, tumor microenvironment (TME) phenotype identification, thereby helping ccRCC patients to make better therapeutic decisions.

Identification of Key DNA methylation sites related to differentially expressed genes in Lung squamous cell carcinoma

Changes in DNA methylation level at some CpG locus are closely associated with the occurrence of lung squamous cell carcinoma (LUSC). However, its specific regulatory mechanism is still unclear. Therefore, it is necessary to systematically identify and analyze those key CpG sites whose DNA methylation levels are closely related to the differential expression of up- and down-regulated genes in LUSC. Due to the dispersion of DNA methylation sites in different regions of genome, to study the correlation between gene expression level and DNA methylation, we divided gene into 6 non-overlapping functional regions and proposed a two-step correlation analysis method to identify differential DNA methylation sites and matched differential expression genes. As a results, we obtained 39 key CpG sites scattered in 27 genes. Through comparative analysis of LUSC-normal sample pairs, we found that these sites and genes can accurately cluster LUSC samples and normal samples. Finally, we used these sites and genes to distinguish LUSC from normal samples. The results suggest that they can be used as effective biomarkers for identifying LUSC. In addition, the proposed two-step correlation analysis method can also be extended to the identification of biomarkers of other cancers and diseases.

Exploring the Interplay Between Vitamin B12-related Biomarkers, DNA Methylation, and Gene-Nutrition Interaction in Esophageal Precancerous Lesions

BACKGROUND

Vitamin B12 depletion has been suggested to be associated with esophageal precancerous lesions (EPL). However, the potential mechanisms remain unclear.

AIMS

This study aims to evaluate the role of vitamin B12 and its regulated epigenetic modification in EPL and provide preliminary information on the identification of potential molecular biomarkers for the early prediction of EPL.

METHODS

We collected information and samples from the Early Diagnosis and Early Treatment Project of Esophageal Cancer database from 200 EPL cases and 200 matched controls. Vitamin B12, one-carbon metabolism biomarkers, genetic polymorphism of TCN2 C776G, and DNA methylation were compared. Preliminarily identified candidate promoters of differentially methylated CpG positions were further verified by targeted bisulfite sequencing.

RESULTS

EPL cases had significantly lower serum levels of vitamin B12 and transcobalamin II, and higher serum levels of homocysteine and 5-methyltetrahydrofolate than controls. The TCN2 C776G polymorphism was found to be associated with susceptibility to EPL and may interact with vitamin B12 nutritional status to influence the risk of EPL in male subjects. In addition, global hypomethylation related to vitamin B12 depletion was observed in EPL cases, along with region-specific hypermethylation of UGT2B15 and FGFR2 promoters.

CONCLUSIONS

This study suggests that vitamin B12 depletion may be associated with aberrant DNA methylation and increased risk of EPL through the one-carbon metabolism pathway, presents that the TCN2 C776G polymorphism may interact with vitamin B12 nutritional status to affect EPL risk in males, and also identifies specific locations in the UGT2B15 and FGFR2 promoters with potential as promising molecular biomarkers.

The role of dietary polyphenols in alternating DNA methylation in cancer

Natural products such as curcumin, quercetin, and resveratrol have been shown to have antitumor effectsand several studies have examined their role in treating cancer, either alone or in combination with other chemotherapeutic drugs. These compounds are capable of affecting different cancer-related mechanisms, such as proliferation, inflammation, invasion, and metastasis. Along with all of the benefits of these agents, affecting epigenetic processes is one of the most important aspects of their impact. Epigenetic modifications can be categorized into three main processes that include DNA methylation, histone modification, and regulation of small non-coding RNAs. Therefore, targeting DNA methylation can be used as a cancer treatment strategy by identifying or developing methylation modulators. Herein, we take a look into the studies investigating the role of natural products (e.g. curcumin, resveratrol, epigallocatechin gallate (EGCG), and quercetin) in alternating the DNA methylation status of various cancer cells. We discuss how these compounds reduce the expression of enzymes mediating the methylation of tumor suppressor genes and thereby, increasing the expression of tumor suppressors while reactivating antitumor signaling pathways.

The important role of miR-1-3p in cancers

Cancer is a malignant tumor that seriously threatens human life and health. At present, the main treatment methods include surgical resection, chemotherapy, radiotherapy, and immunotherapy. However, the mechanism of tumor occurrence and development is complex, and it produces resistance to some traditional treatment methods, leading to treatment failure and a high mortality rate for patients. Therefore, exploring the molecular mechanisms of tumor occurrence, development, and drug resistance is a very important task. MiRNAs are a type of non-coding small RNA that regulate a series of biological effects by binding to the 3'-UTR of the target mRNA, degrading the mRNA, or inhibiting its translation. MiR-1-3p is an important member of them, which is abnormally expressed in various tumors and closely related to the occurrence and development of tumors. This article introduces miR-1-3p from multiple aspects, including its production and regulation, role in tumor occurrence and development, clinical significance, role in drug resistance, and approaches for targeting miR-1-3p. Intended to provide readers with a comprehensive understanding of the important role of miR-1-3p in tumors.

GPR37 expression as a prognostic marker in gliomas: a bioinformatics-based analysis

BACKGROUND

Gliomas are the most frequently diagnosed primary brain tumors, and are associated with multiple molecular aberrations during their development and progression. GPR37 is an orphan G protein-coupled receptor (GPCR) that is implicated in different physiological pathways in the brain, and has been linked to various malignancies. The aim of this study was to explore the relationship between GPR37 gene expression and the clinicopathological factors, patient prognosis, tumor-infiltrating immune cell signature GSEA and methylation levels in glioma.

METHODS

We explored the diagnostic value, clinical relevance, and molecular function of GPR37 in glioma using TCGA, STRING, cBioPortal, Tumor Immunity Estimation Resource (TIMER) database and MethSurv databases. Besides, the "ssGSEA" algorithm was conducted to estimate immune cells infiltration abundance, with 'ggplot2' package visualizing the results. Immunohistochemical staining of clinical samples were used to verify the speculations of bioinformatics analysis.

RESULTS

GPR37 expression was significantly higher in the glioma tissues compared to the normal brain tissues, and was linked to poor prognosis. Functional annotation of GPR37 showed enrichment of ether lipid metabolism, fat digestion and absorption, and histidine metabolism. In addition, GSEA showed that GPR37 was positively correlated to the positive regulation of macrophage derived foam cell differentiation, negative regulation of T cell receptor signaling pathway, neuroactive ligand receptor interaction, calcium signaling pathway, and negatively associated with immunoglobulin complex, immunoglobulin complex circulating, ribosome and spliceosome mediated by circulating immunoglobulin etc. TIMER2.0 and ssGSEA showed that GPR37 expression was significantly associated with the infiltration of T cells, CD8 T cell, eosinophils, macrophages, neutrophils, NK CD56dim cells, NK cells, plasmacytoid DCs (pDCs), T helper cells and T effector memory (Tem) cells. In addition, high GPR37 expression was positively correlated with increased infiltration of M2 macrophages, which in turn was associated with poor prognosis. Furthermore, GPR37 was positively correlated with various immune checkpoints (ICPs). Finally, hypomethylation of the GPR37 promoter was associated with its high expression levels and poor prognosis in glioma.

CONCLUSION

GPR37 had diagnostic and prognostic value in glioma. The possible biological mechanisms of GPR37 provide novel insights into the clinical diagnosis and treatment of glioma.

Epigenetic Modulators as Therapeutic Agents in Cancer

Epigenetics play a crucial role in gene regulation and cellular processes. Most importantly, its dysregulation can contribute to the development of tumors. Epigenetic modifications, such as DNA methylation and histone acetylation, are reversible processes that can be utilized as targets for therapeutic intervention. DNA methylation inhibitors disrupt DNA methylation patterns by inhibiting DNA methyltransferases. Such inhibitors can restore normal gene expression patterns, and they can be effective against various forms of cancer. Histone deacetylase inhibitors increase histone acetylation levels, leading to altered gene expressions. Like DNA methylation inhibitors, histone methyltransferase inhibitors target molecules involved in histone methylation. Bromodomain and extra-terminal domain inhibitors target proteins involved in gene expression. They can be effective by inhibiting oncogene expression and inducing anti-proliferative effects seen in cancer. Understanding epigenetic modifications and utilizing epigenetic inhibitors will offer new possibilities for cancer research.

Hypomethylation of CD3D promoter induces immune cell infiltration and supports malignant phenotypes in uveal melanoma

Alterations in DNA methylation in malignant diseases have been heralded as promising targets for diagnostic, prognostic, and predictive values. This study was based on epigenetic alterations and immune cell infiltration analysis to investigate the mechanism of CD3D methylation in uveal melanoma (UM). Bioinformatics analysis was performed on transcriptome data, 450 K methylation data, and clinical information of UM patients from the TCGA database. Stromal and immune cell infiltration was evaluated by calculating the StromalScore and ImmuneScore of UM samples. UM samples were divided into high and low StromalScore and ImmuneScore groups, followed by differential and enrichment analyses. PPI network construction and correlation analysis was used to identify the core prognosis-related genes. The bioinformatics analysis results were confirmed in UM cell experiments. StromalScore and ImmuneScore were significantly associated with the prognosis of UM patients. CD3D, IRF1, CCL3, and FN1 were identified as core genes driven by methylation that affected the prognosis of UM patients. CD3D expression showed the highest correlation with its methylation and was closely related to the four key immune cells in UM development. CD3D was hypomethylated and abundantly expressed in UM cells, while silencing of CD3D inhibited the proliferation, migration, and invasion of UM cells in vitro. In summary, this study identifies hypomethylation of CD3D promoter in UM, which was associated with immune cell infiltration of UM.

Identification and validation of SERPINE1 as a prognostic and immunological biomarker in pan-cancer and in ccRCC

Background: SERPINE1, a serine protease inhibitor involved in the regulation of the plasminogen activation system, was recently identified as a cancer-related gene. However, its clinical significance and potential mechanisms in pan-cancer remain obscure. Methods: In pan-cancer multi-omics data from public datasets, including The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx), and online web tools were used to analyze the expression of SERPINE1 in different cancers and its correlation with prognosis, genetic alteration, DNA promoter methylation, biological processes, immunoregulator expression levels, immune cell infiltration into tumor, tumor mutation burden (TMB), microsatellite instability (MSI), immunotherapy response and drug sensitivity. Further, two single-cell databases, Tumor Immune Single-cell Hub 2 (TISCH2) and CancerSEA, were used to explore the expression and potential roles of SERPINE1 at a single-cell level. The aberrant expression of SERPINE1 was further verified in clear cell renal cell carcinoma (ccRCC) through qRT-PCR of clinical patient samples, validation in independent cohorts using The Gene Expression Omnibus (GEO) database, and proteomic validation using the Clinical Proteomic Tumor Analysis Consortium (CPTAC) database. Results: The expression of SERPINE1 was dysregulated in cancers and enriched in endothelial cells and fibroblasts. Copy number amplification and low DNA promoter methylation could be partly responsible for high SERPINE1 expression. High SERPINE1 expression was associated with poor prognosis in 21 cancers. The results of gene set enrichment analysis (GSEA) indicated SERPINE1 involvement in the immune response and tumor malignancy. SERPINE1 expression was also associated with the expression of several immunoregulators and immune cell infiltration and could play an immunosuppression role. Besides, SERPINE1 was found to be related with TMB, MSI, immunotherapy response and sensitivity to several drugs in cancers. Finally, the high expression of SERPINE1 in ccRCC was verified using qRT-PCR performed on patient samples, six independent GEO cohorts, and proteomic data from the CPTAC database. Conclusion: The findings of the present study revealed that SERPINE1 exhibits aberrant expression in various types of cancers and is associated with cancer immunity and tumor malignancy, providing novel insights for individualized cancer treatment.

The multi-omics analyses of acsl1 reveal its translational significance as a tumor microenvironmental and prognostic biomarker in clear cell renal cell carcinoma

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is the dominant subtype of kidney cancer. Dysregulation of long-chain acyl-CoA synthetase 1 (ACSL1) is strongly implicated in undesirable results in varieties of cancers. Nevertheless, the dysregulation and associated multi-omics characteristics of ACSL1 in ccRCC remain elusive.

METHODS

We probed the mRNA and protein profiles of ACSL1 in RCC using data from the Cancer Genome Atlas, Gene Expression Omnibus, the Human Protein Atlas (HPA), and Clinical Proteomic Tumor Analysis Consortium (CPTAC) and verified them in our patient cohort and RCC cell lines. Correlations between ACSL1 expression and clinicopathological features, epigenetic modification and immune microenvironment characteristics were analyzed to reveal the multi-omics profile associated with ACSL1.

RESULTS

ACSL1 was down-regulated in ccRCC tissues compared to adjacent normal tissues. Lower expression of ACSL1 was linked to unfavorable pathological parameters and prognosis. The dysregulation of ACSL1 was greatly ascribed to CpG island-associated methylation modification. The ACSL1 high-expression subgroup had enriched fatty acid metabolism-related pathways and high expression of ferroptosis-related genes. In contrast, the ACSL1 low-expression subgroup exhibited higher immune and microenvironment scores, elevated expression of immune checkpoints PDCD1, CTLA4, LAG3, and TIGIT, and higher TIDE scores. Using data from the GDSC database, we corroborated that down-regulation of ACSL1 was associated with higher sensitivity towards Erlotinib, Pazopanib, and PI3K-Akt-mTOR-targeted therapeutic strategies.

CONCLUSION

Taken together, our findings point to ACSL1 as a biomarker for prognostic prediction of ccRCC, identifying the tumor microenvironment (TME) phenotype, and even contributing to treatment decision-making in ccRCC patients.

An evolutionary perspective of lifespan and epigenetic inheritance

In the last decade epigenetics has come to the fore as a discipline which is central to biogerontology. Age associated epigenetic changes are routinely linked with pathologies, including cardiovascular disease, cancer, and Alzheimer's disease; moreover, epigenetic clocks are capable of correlating biological age with chronological age in many species including humans. Recent intriguing empirical observations also suggest that inherited epigenetic effects could influence lifespan/longevity in a variety of organisms. If this is the case, an imperative exists to reconcile lifespan/longevity associated inherited epigenetic processes with the evolution of ageing. This review will critically evaluate inherited epigenetic effects from an evolutionary perspective. The overarching aim is to integrate the evidence which suggests epigenetic inheritance modulates lifespan/longevity with the main evolutionary theories of ageing.

Cangfu Daotan Wan alleviates polycystic ovary syndrome with phlegm-dampness syndrome via disruption of the PKP3/ERCC1/MAPK axis

BACKGROUND/AIM

Cangfu Daotan Wan (CFDTW) has been widely used for polycystic ovary syndrome (PCOS) patients in the type of stagnation of phlegm and dampness. In this study, we aimed to evaluate the mechanism underlying the therapeutic effect of CFDTW on PCOS with phlegm-dampness syndrome (PDS).

METHODS

In silico analysis was adopted to identify CFDTW potential targets and the downstream pathways in the treatment of PCOS. Expression of PKP3 was examined in the ovarian granulosa cells from PCOS patients with PDS and rat PCOS models induced by dehydroepiandrosterone (DHEA). PKP3/ERCC1 was overexpressed or underexpressed or combined with CFDTW treatment in ovarian granulosa cells to assay the effect of CFDTW on ovarian granulosa cell functions via the PKP3/MAPK/ERCC1 axis.

RESULTS

Clinical samples and ovarian granulosa cells of rat models were characterized by hypomethylated PKP3 promoter and upregulated PKP3 expression. CFDTW reduced PKP3 expression by enhancing the methylation of PKP3 promoter, leading to proliferation of ovarian granulosa cells, increasing S and G2/M phase-arrested cells, and arresting their apoptosis. PKP3 augmented ERCC1 expression by activating the MAPK pathway. In addition, CFDTW facilitated the proliferation of ovarian granulosa cells and repressed their apoptosis by regulating PKP3/MAPK/ERCC1 axis.

CONCLUSION

Taken together, this study illuminates how CFDTW confers therapeutic effects on PCOS patients with PDS, which may offer a novel theranostic marker in PCOS.

The biological significance of cuproptosis-key gene MTF1 in pan-cancer and its inhibitory effects on ROS-mediated cell death of liver hepatocellular carcinoma

Metal regulatory transcription factor 1 (MTF1) has been reported to be correlated with several human diseases, especially like cancers. Exploring the underlying mechanisms and biological functions of MTF1 could provide novel strategies for clinical diagnosis and therapy of cancers. In this study, we conducted the comprehensive analysis to evaluate the profiles of MTF1 in pan-cancer. For example, TIMER2.0, TNMplot and GEPIA2.0 were employed to analyze the expression values of MTF1 in pan-cancer. The methylation levels of MTF1 were evaluated via UALCAN and DiseaseMeth version 2.0 databases. The mutation profiles of MTF1 in pan-cancers were analyzed using cBioPortal. GEPIA2.0, Kaplan-Meier plotter and cBioPortal were also used to explore the roles of MTF1 in cancer prognosis. We found that high MTF1 expression was related to poor prognosis of liver hepatocellular carcinoma (LIHC) and brain lower grade glioma (LGG). Also, high expression level of MTF1 was associated with good prognosis of kidney renal clear cell carcinoma (KIRC), lung cancer, ovarian cancer and breast cancer. We investigated the genetic alteration and methylation levels of MTF1 between the primary tumor and normal tissues. The relationship between MTF1 expression and several immune cells was analyzed, including T cell CD8 + and dendritic cells (DC). Mechanically, MTF1-interacted molecules might participate in the regulation of metabolism-related pathways, such as peptidyl-serine phosphorylation, negative regulation of cellular amide metabolic process and peptidyl-threonine phosphorylation. Single cell sequencing indicated that MTF1 was associated with angiogenesis, DNA repair and cell invasion. In addition, in vitro experiment indicated knockdown of MTF1 resulted in the suppressed cell proliferation, increased reactive oxygen species (ROS) and promoted cell death in LIHC cells HepG2 and Huh7. Taken together, this pan-cancer analysis of MTF1 has implicated that MTF1 could play an essential role in the progression of various human cancers.

Molecular triage of cervical screening samples in women 55-59 years of age: a pilot study

BACKGROUND

With HPV screening the specificity of screening positives has decreased, even with a cytological triage test. Increases in colposcopies and detection of benign or low-grade dysplasia are reported, not least in older women. These results highlight the necessity to find other triage tests in HPV screening strategies, so that women can be more accurately selected for colposcopy, thus minimizing the clinically irrelevant findings.

METHODS

The study included 55- to 59-year-old women who exited the screening with normal cytology, but later in a follow-up test were positive for the HPV genotypes 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66 and 68 and had a cervical cone biopsy done. To model a screening situation with hrHPV-positive women, three different triage strategies, namely, cytology, genotyping and methylation, were performed. The study considered the effect of direct referral to colposcopy for HPV genotypes 16, 18, 31, 33, 45, 52 and 58, and methylation for FAM19A4 and hsa-mir124-2 and/or any form of abnormal cytology.

RESULTS

Seven out of 49 women aged 55-59 years with hrHPV had a cone biopsy with high-grade squamous intraepithelial lesion. No triage method found all cases, and when comparing positive and negative predictive value and false negative rate, cytology showed better results than genotyping and methylation.

CONCLUSION

This study does not support a switch in triage strategies from cytology to hrHPV genotyping and methylation for women above 55 years of age yet, but demonstrates the need for more evidence on molecular triage strategies.

The association between CTSZ methylation in peripheral blood and breast cancer in Chinese women

Purpose

Previous studies have shown that DNA methylation in peripheral blood may be associated with breast cancer (BC). To explore the association between the methylation level of the Cathepsin Z (CTSZ) gene in peripheral blood and BC, we conducted a case-control study in the Chinese population.

Methods

Peripheral blood samples were collected from 567 BC cases, 635 healthy controls, and 303 benign breast disease (BBD) cases. DNA extraction and bisulfite-specific PCR amplification were performed for all samples. The methylation levels of seven sites of the CTSZ gene were quantitatively determined by Mass spectrometry. The odds ratios (ORs) of CpG sites were evaluated for BC risk using per 10% reduction and quartiles analyses by logistic regression.

Results

Our analysis showed that five out of the seven CpG sites exhibited significant associations with hypomethylation of CTSZ and BC, compared to healthy controls. The highest OR was for Q2 of CTSZ_CpG_1 (OR: 1.62, P=0.006), particularly for early-stage breast cancer in the case of per 10% reduction of CTSZ_CpG_1 (OR: 1.20, P=0.003). We also found that per 10% reduction of CTSZ_CpG_5 (OR: 1.39, P=0.004) and CTSZ_CpG_7,8 (OR: 1.35, P=0.005) were associated with increased BC risk. Our study also revealed that four out of seven CpG sites were linked to increased BC risk in women under 50 years of age, compared to healthy controls. The highest OR was for per 10% reduction of CTSZ_CpG_1 (OR: 1.47, P<0.001). Additionally, we found that BC exhibited lower methylation levels than BBD at CTSZ_CpG_4 (OR for Q1: 2.18, P<0.001) and CTSZ_CpG_7,8 (OR for Q1: 2.01, P=0.001). Furthermore, we observed a correlation between methylation levels and tumor stage, ER, and HER2 status in BC patients.

Conclusion

Overall, our findings suggest that altered CTSZ methylation levels in peripheral blood may be associated with breast cancer, particularly in young women, and may serve as a potential biomarker for early-stage BC.

Elevated LILRB1 expression predicts poor prognosis and is associated with tumor immune infiltration in patients with glioma

BACKGROUND

Leukocyte immunoglobulin-like receptor subfamily B1 (LILRB1) is regarded as an inhibitory molecule. However, the importance of LILRB1 expression in glioma has not yet been determined. This investigation examined the immunological signature, clinicopathological importance and prognostic value of LILRB1 expression in glioma.

METHODS

We used data from the UCSC XENA database, the Cancer Genome Atlas (TCGA) database, the Chinese Glioma Genome Atlas (CGGA) database, the STRING database, the MEXPRESS database and our clinical glioma samples to perform bioinformatic analysis and used vitro experiments to examine the predictive value and potential biological roles of LILRB1 in glioma.

RESULTS

Higher LILRB1 expression was considerably present in the higher WHO grade glioma group and was linked to a poorer prognosis in patients with glioma. Gene set enrichment analysis (GSEA) revealed that LILRB1 was positively correlated with the JAK/STAT signaling pathway. LILRB1 combined with tumor mutational burden (TMB) and microsatellite instability (MSI) may be a promising indicator for the effectiveness of immunotherapy in patients with glioma. Increased LILRB1 expression was positively linked with the hypomethylation, M2 macrophage infiltration, immune checkpoints (ICPs) and M2 macrophage makers. Univariate and multivariate Cox regression analyses determined that increased LILRB1 expression was a standalone causal factor for glioma. Vitro experiments determined that LILRB1 positively enhanced the proliferation, migration and invasion in glioma cells. MRI images demonstrated that higher LILRB1 expression was related with larger tumor volume in patients with glioma.

CONCLUSION

Dysregulation of LILRB1 in glioma is correlated with immune infiltration and is a standalone causal factor for glioma.

Intraperitoneal 5-Azacytidine Alleviates Nerve Injury-Induced Pain in Rats by Modulating DNA Methylation

To investigate the role of DNA methylation in modulating chronic neuropathic pain (NPP), identify possible target genes of DNA methylation involved in this process, and preliminarily confirm the medicinal value of the DNA methyltransferases (DNMTs) inhibitor 5-azacytidine (5-AZA) in NPP by targeting gene methylation. Two rat NPP models, chronic constriction injury (CCI) and spinal nerve ligation (SNL), were used. The DNA methylation profiles in the lumbar spinal cord were assayed using an Arraystar Rat RefSeq Promoter Array. The underlying genes with differential methylation were then identified and submitted to Gene Ontology and pathway analysis. Methyl-DNA immunoprecipitation quantitative PCR (MeDIP-qPCR) and quantitative reverse transcription-PCR (RT-qPCR) were used to confirm gene methylation and expression. The protective function of 5-AZA in NPP and gene expression were evaluated via behavioral assays and RT-qPCR, respectively. Analysis of the DNA methylation patterns in the lumbar spinal cord indicated that 1205 differentially methylated fragments in CCI rats were located within DNA promoter regions, including 638 hypermethylated fragments and 567 hypomethylated fragments. The methylation levels of Grm4, Htr4, Adrb2, Kcnf1, Gad2, and Pparg, which are associated with long-term potentiation (LTP) and glutamatergic synapse pathways, were increased with a corresponding decrease in their mRNA expression, in the spinal cords of CCI rats. Moreover, we found that the intraperitoneal injection of 5-AZA (4 mg/kg) attenuated CCI- or SNL-induced mechanical allodynia and thermal hyperalgesia. Finally, the mRNA expression of hypermethylated genes such as Grm4, Htr4, Adrb2, Kcnf1, and Gad2 was reversed after 5-AZA treatment. CCI induced widespread methylation changes in the DNA promoter regions in the lumbar spinal cord. Intraperitoneal 5-AZA alleviated hyperalgesia in CCI and SNL rats, an effect accompanied by the reversed expression of hypermethylated genes. Thus, DNA methylation inhibition represents a promising epigenetic strategy for protection against chronic NPP following nerve injury. Our study lays a theoretical foundation for 5-AZA to become a clinical targeted drug.

Ultrasensitive photoelectrochemical biosensor for DNA 5-methylcytosine analysis based on co-sensitization strategy combined with bridged DNA nanoprobe

Altered DNA methylation in the form of 5-methylcytosine (5-mC) patterns is correlated with disease diagnosis, prognosis, and treatment response. Therefore, accurate analysis of 5-mC is of great significance for the diagnosis of diseases. Here, an efficient enhanced photoelectrochemical (PEC) biosensor was designed for the quantitative analysis of DNA 5-mC based on a cascaded energy level aligned co-sensitization strategy coupling with the bridged DNA nanoprobe (BDN). Firstly, Au nanoparticle/graphite phase carbon nitride/titanium dioxide (AuNPs/g-C₃N₄@TiO₂) nanocomposite was synthesized through in situ growth of AuNPs on g-C₃N₄@TiO₂ surface as a matrix to provide a stable background signal. Next, BDN with a high mass transfer rate synthesized from a pair of DNA tetrahedral as nanomechanical handles was used as a capture probe to bind to the target sequence. The polydopamine nanosphere was applied to load with CdTe QDs (PDANS-CdTe QDs) as a photocurrent label of 5-mC antibodies. When the 5-mC existed, a large number of PDANS-Ab-CdTe QDs were introduced to the electrode surface, the formed CdTe QDs/AuNPs/g-C₃N₄@TiO₂ co-sensitive structure could effectively enhance the electron transfer capability and photocurrent response rate due to the effective cascade energy level arrangement, leading to a significantly enhanced photocurrent signal. The proposed PEC biosensor manifested a wide range from 10^-17 M to 10^-7 M and a detection limit of 2.2 aM. Meanwhile, the excellent performance indicated the practicability of the designed strategy, thus being capable of the clinical diagnosis of 5-mC.

Therapeutic strategies of dual-target small molecules to overcome drug resistance in cancer therapy

Despite some advances in targeted therapeutics of human cancers, curative cancer treatment still remains a tremendous challenge due to the occurrence of drug resistance. A variety of underlying resistance mechanisms to targeted cancer drugs have recently revealed that the dual-target therapeutic strategy would be an attractive avenue. Compared to drug combination strategies, one agent simultaneously modulating two druggable targets generally shows fewer adverse reactions and lower toxicity. As a consequence, the dual-target small molecule has been extensively explored to overcome drug resistance in cancer therapy. Thus, in this review, we focus on summarizing drug resistance mechanisms of cancer cells, such as enhanced drug efflux, deregulated cell death, DNA damage repair, and epigenetic alterations. Based upon the resistance mechanisms, we further discuss the current therapeutic strategies of dual-target small molecules to overcome drug resistance, which will shed new light on exploiting more intricate mechanisms and relevant dual-target drugs for future cancer therapeutics.

RNA binding protein SAMD4: current knowledge and future perspectives

SAMD4 protein family is a class of novel RNA-binding proteins that can mediate post-transcriptional regulation and translation repression in eukaryotes, which are highly conserved from yeast to humans during evolution. In mammalian cells, SAMD4 protein family consists of two members including SAMD4A/Smaug1 and SAMD4B/Smaug2, both of which contain common SAM domain that can specifically bind to different target mRNAs through stem-loop structures, also known as Smaug recognition elements (SREs), and regulate the mRNA stability, degradation and translation. In addition, SAMD4 can form the cytoplasmic mRNA silencing foci and regulate the translation of SRE-containing mRNAs in neurons. SAMD4 also can form the cytosolic membrane-less organelles (MLOs), termed as Smaug1 bodies, and regulate mitochondrial function. Importantly, many studies have identified that SAMD4 family members are involved in various pathological processes including myopathy, bone development, neural development, and cancer occurrence and progression. In this review, we mainly summarize the structural characteristics, biological functions and molecular regulatory mechanisms of SAMD4 protein family members, which will provide a basis for further research and clinical application of SAMD4 protein family.

Arachidonate lipoxygenases 5 is a novel prognostic biomarker and correlates with high tumor immune infiltration in low-grade glioma

Objective: To investigate the prognostic value of arachidonate lipoxygenases 5 (ALOX5) expression and methylation, and explore the immune functions of arachidonate lipoxygenases 5 expression in low-grade glioma (LGG). Materials and Methods: Using efficient bioinformatics approaches, the differential expression of arachidonate lipoxygenases 5 and the association of its expression with clinicopathological characteristics were evaluated. Then, we analyzed the prognostic significance of arachidonate lipoxygenases 5 expression and its methylation level followed by immune cell infiltration analysis. The functional enrichment analysis was conducted to determine the possible regulatory pathways of arachidonate lipoxygenases 5 in low-grade glioma. Finally, the drug sensitivity analysis was performed to explore the correlation between arachidonate lipoxygenases 5 expression and chemotherapeutic drugs. Results: arachidonate lipoxygenases 5 mRNA expression was increased in low-grade glioma and its expression had a notable relation with age and subtype (p < 0.05). The elevated mRNA level of arachidonate lipoxygenases 5 could independently predict the disease-specific survival (DSS), overall survival (OS), and progression-free interval (PFI) (p < 0.05). Besides, arachidonate lipoxygenases 5 expression was negatively correlated with its methylation level and the arachidonate lipoxygenases 5 hypomethylation led to a worse prognosis (p < 0.05). The arachidonate lipoxygenases 5 expression also showed a positive connection with immune cells, while low-grade glioma patients with higher immune cell infiltration had poor survival probability (p < 0.05). Further, arachidonate lipoxygenases 5 might be involved in immune- and inflammation-related pathways. Importantly, arachidonate lipoxygenases 5 expression was negatively related to drug sensitivity. Conclusion: arachidonate lipoxygenases 5 might be a promising biomarker, and it probably occupies a vital role in immune cell infiltration in low-grade glioma.

DEF6 has potential to be a biomarker for cancer prognosis: A pan-cancer analysis

Introduction

DEF6 is a gene associated with the immune system and is thought to play a crucial role in autoimmunity. There are few DEF6-related studies in cancer, and it is assumed that DEF6 is a proto-oncogene. There is currently no pan-cancer analysis of DEF6, and we performed a systematic and comprehensive pan-cancer analysis of DEF6 in an attempt to reveal its role and function in cancer.

Methods

The data were analyzed by mining databases available to the public and by using R software. Moreover, immunohistochemistry was used to validate the results.

Results

Our results revealed that DEF6 is commonly aberrantly expressed in cancer and its expression is strongly correlated with survival prognosis in a variety of cancer types. Through correlation analysis we found that DEF6 was associated with multiple immune genes and was closely related to immune infiltration. In the enrichment analysis, DEF6 may have cross-talk with multiple cancer pathways and exert oncogenic or pro-cancer functions. In addition, we collected pathological samples from colorectal cancer patients for immunohistochemical analysis and found that patients with higher immunohistochemical scores had more lymph node metastases, higher CA199, and bigger tumor size.

Discussion

Overall, DEF6 expression is closely related to cancers and has the potential to act as a cancer biomarker.

Methylation-mediated silencing of EDN3 promotes cervical cancer proliferation, migration and invasion

Cervical cancer (CC) remains one of the leading causes of cancer-related deaths worldwide. However, cervical cancer is preceded by the pre-malignant cervical intraepithelial neoplasia (CIN) that can last for up to 20 years before becoming malignant. Therefore, early screening is the key to prevent the progression of cervical lesions into invasive cervical cancer and decrease the incidence. The genes, down-regulated and hypermethylated in cancers, may provide potential drug targets for cervical cancer. In our current study, using the datasets from Gene Expression Omnibus (GEO) and the Cancer Genome Atlas (TCGA) databases, we found that endothelin 3 (EDN3) was downregulated and hypermethylated in cervical squamous cell carcinoma (CSCC). The further analysis in GSE63514 (n=128) dataset and in our samples (n=221) found that the expression of EDN3 was decreased with the degree of cervical lesions. Pyrosequencing was performed to evaluate 4 CpG sites of the EDN3 promoter region in our samples (n=469). The data indicated that the methylation level of EDN3 was increased with the degree of cervical lesions. EDN3 silencing mediated by methylation can be blocked by 5-Azacytidine (5-Aza), a DNA methyltransferase 1 (DNMT1) inhibitor, treatment in cervical cancer cell lines. Ethynyldeoxyuridine (EdU) assay, would-healing assay, clone formation assay and transwell assay were conducted to investigate the biological function of EDN3 in cervical cancer cell lines. The results of these experiments confirmed that overexpression of EDN3 could inhibit the proliferation, clone formation, migration and invasion of cervical cancer cells. EDN3 may provide potential biomarker and therapeutic target for CSCC.

CCNF is a potential pancancer biomarker and immunotherapy target

Background

CCNF catalyzes the transfer of ubiquitin molecules from E2 ubiquitin-conjugating enzymes to target proteins, thereby regulating the G1/S or G2/M transition of tumor cells. Thus far, CCNF expression and its potential as a pancancer biomarker and immunotherapy target have not been reported.

Methods

TCGA datasets and the R language were used to analyze the pancancer gene expression, protein expression, and methylation levels of CCNF; the relationship of CCNF expression with overall survival (OS), recurrence-free survival (RFS), immune matrix scores, sex and race; and the mechanisms for posttranscriptional regulation of CCNF.

Results

CCNF expression analysis showed that CCNF mRNA expression was higher in cancer tissues than in normal tissues in the BRCA, CHOL, COAD, ESCA, HNSC, LUAD, LUSC, READ, STAD, and UCEC; CCNF protein expression was also high in many cancer tissues, indicating that it could be an important predictive factor for OS and RFS. CCNF overexpression may be caused by CCNF hypomethylation. CCNF expression was also found to be significantly different between patients grouped based on sex and race. Overexpression of CCNF reduces immune and stromal cell infiltration in many cancers. Posttranscriptional regulation analysis showed that miR-98-5p negatively regulates the expression of the CCNF gene.

Conclusion

CCNF is overexpressed across cancers and is an adverse prognostic factor in terms of OS and RFS in many cancers; this phenomenon may be related to hypomethylation of the CCNF gene, which could lead to cancer progression and worsen prognosis. In addition, CCNF expression patterns were significantly different among patients grouped by sex and race. Its overexpression reduces immune and stromal cell infiltration. miR-98-5p negatively regulates CCNF gene expression. Hence, CCNF is a potential pancancer biomarker and immunotherapy target.

Blood-based DNA methylation signatures in cancer: A systematic review

DNA methylation profiles are in dynamic equilibrium via the initiation of methylation, maintenance of methylation and demethylation, which control gene expression and chromosome stability. Changes in DNA methylation patterns play important roles in carcinogenesis and primarily manifests as hypomethylation of the entire genome and the hypermethylation of individual loci. These changes may be reflected in blood-based DNA, which provides a non-invasive means for cancer monitoring. Previous blood-based DNA detection objects primarily included circulating tumor DNA/cell-free DNA (ctDNA/cfDNA), circulating tumor cells (CTCs) and exosomes. Researchers gradually found that methylation changes in peripheral blood mononuclear cells (PBMCs) also reflected the presence of tumors. Blood-based DNA methylation is widely used in early diagnosis, prognosis prediction, dynamic monitoring after treatment and other fields of clinical research on cancer. The reversible methylation of genes also makes them important therapeutic targets. The present paper summarizes the changes in DNA methylation in cancer based on existing research and focuses on the characteristics of the detection objects of blood-based DNA, including ctDNA/cfDNA, CTCs, exosomes and PBMCs, and their application in clinical research.

A pan-cancer analysis of the oncogenic role of procollagen C-endopeptidase enhancer (PCOLCE) in human

There is no evidence showing that the expression of procollagen C-endopeptidase enhancer (PCOLCE) is associated with human tumors, and pan-cancer analysis is not available. Based on public databases such as the cancer genome atlas, we investigated the potential role of PCOLCE expression in 33 different human tumors. PCOLCE expression in 11 tumors was significantly correlated with tumor prognosis and was a prognostic predictor for pancreatic adenocarcinoma, thymoma and CES. We also found that PCOLCE expression correlated with the immune microenvironment of tumors and the level of cancer-associated fibroblast infiltration. PCOLCE is a potential predictor of small molecule targeted drugs and immune checkpoint inhibitors. Finally, we found by enrichment analysis that PCOLCE localizes to extracellular structures and the extracellular matrix and exerts substantial effects on tumors through the PI3K-Akt and AGE-RAGE signaling pathways. We have a preliminary and relatively comprehensive understanding of the role of PCOLCE in various tumors.

Pan-Cancer Analysis of the Roles and Driving Forces of RAB42

RAB42 is a member of the RAS family. However, the roles and driving forces for RAB42 in tumors remain elusive. In this study, we performed a comprehensive pan-cancer analysis of the roles and regulatory mechanisms of RAB42 using bioinformatics and experiments. Online databases such as Sanger Box, ACLBI and TIDE were used to search for the expression levels, prognostic value and immune features of RAB42. We observed that RAB42 expression was upregulated in most tumors and was closely associated with poor prognosis. Enrichment analysis indicated that RAB42 was related to multiple biological functions, especially the immune process. RAB42 expression had a positive correlation with immune cell infiltration and immune checkpoint gene expression. RAB42 had a high predictive value for immunotherapy efficiency. Our study screened out susceptible drugs for the RAB42 protein by sensitivity analysis and virtual screening. Many key driver genes such as TP53 contributed to RAB42 expression. DNA methylation, super-enhancer and non-coding RNAs were the epigenetic factors responsible for RAB42 expression. In brief, RAB42 could serve as a diagnostic and prognostic biomarker in many tumor types. RAB42 might be a predictive biomarker and a new target for immunotherapy. Genetic and epigenetic factors were essential for RAB42 overexpression in tumors.

Genome-wide DNA methylation pattern in whole blood of patients with coal-burning arsenic poisoning

Exposure to coal-burning arsenic leads to an increased risk of cancer, multi-systems damage and chronic diseases, with DNA methylation one potential mechanism of arsenic toxicity. There are few studies on genome-wide methylation in the coal-burning arsenic poisoning population. Illumina 850 K methylation beadchip is the most suitable technology for DNA methylation of epigenome-wide association analysis. This study used 850 K to detect changes in Genome-wide DNA methylation in whole blood samples of 12 patients with coal-burning arsenic poisoning ( Arsenic poisoning group) and four healthy control participants (Healthy control group). There is clearly abnormal genome-wide DNA methylation in coal-burning arsenic poisoning, with 647 significantly different methylation positions, 524 different methylation regions and 335 significantly different methylation genes in arsenic poisoning patients compared with healthy controls. Further functional analysis of Gene ontology (GO) and Kyoto encyclopedia of genes (KEGG) found 592 GO items and 131 KEGG pathways between patients of coal-burning arsenic poisoning and healthy control. Then, analysis of gene degree and combined-score identified NAPRT1, NT5C3B, NEDD4L, SLC22A3 and RAB11B as target genes. Further validation by qRT-PCR indicates that mRNA expression of five genes changes significantly in the arsenic poisoning group (n = 72) compared to the healthy control group (n = 72). These results showed the genome-wide methylation pattern and highlighted five critical genes within the coal-burning arsenic poisoning population that involve Nicotinate and nicotinamide metabolism, Choline metabolism in cancer, and Ubiquitin mediated proteolysis. Next, the methylation profile of coal burning arsenic poisoning will be further excavation and the mechanism of coal burning arsenic poisoning will be further explored from five genes related pathways and functions.

Epigenetics and genetics of hepatoblastoma: Linkage and treatment

Hepatoblastoma is a malignant embryonal tumor with multiple differentiation modes and is the clearest liver malignancy in children. However, little is known about genetic and epigenetic events in Hepatoblastoma. Increased research has recently demonstrated, unique genetic and epigenetic events in Hepatoblastoma, providing insights into its origin and precise treatment. Some genetic disorders and congenital factors are associated with the risk of Hepatoblastoma development, such as the Beckwith-Wiedemann syndrome, Familial Adenomatous polyposis, and Hemihypertrophy. Epigenetic modifications such as DNA modifications, histone modifications, and non-coding RNA regulation are also essential in the development of Hepatoblastoma. Herein, we reviewed genetic and epigenetic events in Hepatoblastoma, focusing on the relationship between these events and cancer susceptibility, tumor growth, and prognosis. By deciphering the genetic and epigenetic associations in Hepatoblastoma, tumor pathogenesis can be clarified, and guide the development of new anti-cancer drugs and prevention strategies.

Mapping Genetics and Epigenetics to Explore the Pathways beyond the Correlated Ageing Phenotype

Ageing is defined by the decline in the biological and physiological functions over time, which leads to health problems and increases risks of diseases. The modern societies are characterised by an ageing population, which represents challenges for the healthcare system. Within this context, there is a need to better understand the biological mechanisms beyond ageing in order to optimise geriatric therapies and medical approaches. Herein, we suggest exploring the genetic and epigenetic patterns related to ageing and correlate them with the ageing-related phenotype of the biological entities in order to establish mechanistic links and map the molecular pathways. Such links would have diverse implications in basic research, in clinics, as well as for therapeutic studies.

Integrative and Comprehensive Pan-Cancer Analysis of Lymphocyte-Specific Protein Tyrosine Kinase in Human Tumors

Lymphocyte-specific protein tyrosine kinase (LCK) is common in a variety of hematologic malignancies but comparatively less common in solid tumors. This study aimed to explore the potential diagnostic and prognostic value of LCK across tumors through integrative and comprehensive pan-cancer analysis, as well as experimental validation. Multiple databases were used to explore the expression, alteration, prognostic value, association with immune infiltration, and potential functional pathways of LCK in pan-cancers. The results were further validated by western blotting and qPCR of patient samples as well as tumor cell lines. High LCK expression typically represents a better prognosis. Notably, drug sensitivity prediction of LCK identified P-529 as a candidate for drug development. Gene Annotations (GO) and KEGG analyses showed significant enrichment of PD-L1 and the T-cell receptor pathway. The results from patient samples and tumor cell lines confirmed these conclusions in LIHC. In conclusion, LCK is differentially expressed in multiple tumors and normal tissues. Further analysis highlighted its association with prognostic implications, pan-cancer genetic alterations, and immune signatures. Our data provide evidence for a diagnostic marker of LCK and the possible use of LCK as a target for the treatment of tumors.

Several areas of overlap between obesity and aging indicate obesity as a biomarker of accelerated aging of human B cell function and antibody responses

Aging and obesity are high risk factors for several conditions and diseases. They are both associated with systemic inflammation and they are both ameliorated by a healthy life style, suggesting that they may share cellular and molecular pathways and underlying mechanisms. A close relationship between aging and obesity is also supported by the observation that the aging overweight/obese population is increasing worldwide, and mechanisms involved will be presented here. A focus of our work is to evaluate if obesity may be considered a good biomarker of accelerated aging of human antibody responses. We will summarize our published results showing the effects of obesity in accelerating age defects in the peripheral B cell pool and how these lead to dysfunctional humoral immunity.

Immunomodulatory effects of decitabine in pearl oyster Pinctada fucata martensii

Decitabine (DAC), an inhibitor of DNA methyltransferase, is typically used to reverse DNA methylation and is considered an epigenetic modifying drug. DNA methylation is crucial to the regulation of gene expression without altering genetic information. Our previous research showed that the DNA methylation levels of many immune-related genes changed after the pre-grafting condition in pearl production. In the present study, we evaluated the DNA methylation level and analyzed transcriptome, enzyme, and antimicrobial activities after DAC treatment to evaluate the effect of DAC on DNA methylation and immune system of pearl oyster Pinctada fucata martensii. Results showed that DAC significantly decreased the level of global DNA methylation in the hemocytes of the pearl oysters. Transcriptome analysis obtained 577 differentially expressed genes (DEGs) between the control and DAC treatment group. The DEGs were mainly enriched in the following pathways: "Relaxin signaling pathway," "Cytosolic DNA-sensing pathway," "Platelet activation," and "Peroxisome," and related genes were overexpressed after DAC treatment. DAC treatment resulted in a substantial increase in the levels of serum superoxide dismutase, interleukin-17, phenol oxidase, tumor necrosis factor, and antimicrobial activity, compared with the control. These results suggested that DAC can alter DNA methylation level, activate immune-related genes, and improve the level of humoral immunity in pearl oysters, thereby increasing our understanding of the mechanism underlying DNA methylation in immune regulation.

A Methylation Diagnostic Model Based on Random Forests and Neural Networks for Asthma Identification

Background

Asthma significantly impacts human life and health as a chronic disease. Traditional treatments for asthma have several limitations. Artificial intelligence aids in cancer treatment and may also accelerate our understanding of asthma mechanisms. We aimed to develop a new clinical diagnosis model for asthma using artificial neural networks (ANN).

Methods

Datasets (GSE85566, GSE40576, and GSE13716) were downloaded from Gene Expression Omnibus (GEO) and identified differentially expressed CpGs (DECs) enriched by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Random forest (RF) and ANN algorithms further identified gene characteristics and built clinical models. In addition, two external validation datasets (GSE40576 and GSE137716) were used to validate the diagnostic ability of the model.

Results

The methylation analysis tool (ChAMP) considered DECs that were up-regulated (n =121) and down-regulated (n =20). GO results showed enrichment of actin cytoskeleton organization and cell-substrate adhesion, shigellosis, and serotonergic synapses. RF (random forest) analysis identified 10 crucial DECs (cg05075579, cg20434422, cg03907390, cg00712106, cg05696969, cg22862094, cg11733958, cg00328720, and cg13570822). ANN constructed the clinical model according to 10 DECs. In two external validation datasets (GSE40576 and GSE137716), the Area Under Curve (AUC) for GSE137716 was 1.000, and AUC for GSE40576 was 0.950, confirming the reliability of the model.

Conclusion

Our findings provide new methylation markers and clinical diagnostic models for asthma diagnosis and treatment.

An insight into therapeutic efficacy of heterocycles as histone modifying enzyme inhibitors that targets cancer epigenetic pathways

Histone modifying enzymes are the key regulators involved in the post-translational modification of histone and non-histone. These enzymes are responsible for the epigenetic control of cellular functions. However, deregulation of the activity of these enzymes results in uncontrolled disorders such as cancer and inflammatory and neurological diseases. The study includes histone acetyltransferases, deacetylases, methyl transferases, demethylases, DNA methyl transferases, and their potent inhibitors which are in a clinical trial and used as medicinal drugs. The present review covers the heterocycles as target-specific inhibitors of histone-modifying enzyme, more specifically histone acetyltransferases. This review also confers more recent reports on heterocycles as potential HAT inhibitors covered from 2016-2022 and future perspectives of these heterocycles in epigenetic therapy.

lncRNA-AC079061.1/VIPR1 axis may suppress the development of hepatocellular carcinoma: a bioinformatics analysis and experimental validation

Background

Hepatocellular carcinoma (HCC) is one of the most malignant tumors to threaten human life, and the survival rate remains low due to delayed diagnosis. Meanwhile, lncRNAs have great potential for application in tumor prognosis, therefore relevant research in hepatocellular carcinoma is indispensable.

Methods

Based on the EZH2 expression, the differentially expressed lncRNAs DElncRNAs), miRNAs (DEmiRNAs), and mRNAs (DEmRNAs) were identified in hepatocellular carcinoma by using the TCGA database. Bioinformatics technology was utilized to determine the effect of key genes in HCC progression. The methylation and immune infiltration analyses were performed to explore the underlying function of hub genes. Finally, cellular function experiments were performed to investigate the association between identified genes and biological phenotypes in HCC.

Results

lncRNA-AC079061.1, hsa-miR-765, and VIPR1 were identified as independent factors that affect the prognosis of hepatocellular carcinoma. The immune infiltration analyses revealed that lncRNA-AC079061.1 can alter the immune microenvironment and thus inhibit the development of HCC by regulating the expression of an immune-related gene (VIPR1). Methylation analyses demonstrated that VIPR1 expression is negatively related to the methylation level in HCC. Experimental results suggested that lncRNA-AC079061.1 and VIPR1 were frequently downregulated in HCC cells, while hsa-miR-765 was significantly upregulated. Moreover, the lncRNA-AC079061.1/VIPR1 axis suppressed the proliferation and invasion of HCC cells.

Conclusion

The present study identified the lncRNA-AC079061.1/VIPR1 axis as a novel biomarker that inhibited the proliferation and invasion of hepatocellular carcinoma, affecting the ultimate disease outcome.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03573-7.