Ferritin heavy chain (FTH1) exerts significant antigrowth effects in breast cancer cells by inhibiting the expression of c-MYC

Overexpression of ferritin heavy chain (FTH1) often associates with good prognosis in breast cancer (BCa), particularly in the triple-negative subtype (triple-negative breast cancer). However, the mechanism by which FTH1 exerts its possible tumor suppressor effects in BCa is not known. Here, we examined the bearing of FTH1 silencing or overexpression on several aspects of BCa cell growth in vitro. FTH1 silencing promoted cell growth and mammosphere formation, increased c-MYC expression, and reduced cell sensitivity to chemotherapy. In contrast, FTH1 overexpression inhibited cell growth, decreased c-MYC expression, and sensitized cancer cells to chemotherapy; silencing of c-MYC recapitulated the effects of FTH1 overexpression. These findings show for the first time that FTH1 suppresses tumor growth by inhibiting the expression of key oncogenes, such as c-MYC.</p

Genetic mutations and non‐coding RNA‐based epigenetic alterations mediating the Warburg effect in colorectal carcinogenesis

Colorectal cancer (CRC) development is a gradual process defined by the accumulation of numerous genetic mutations and epigenetic alterations leading to the adenoma‐carcinoma sequence. Despite significant advances in the diagnosis and treatment of CRC, it continues to be a leading cause of cancer‐related deaths worldwide. Even in the presence of oxygen, CRC cells bypass oxidative phosphorylation to produce metabolites that enable them to proliferate and survive—a phenomenon known as the “Warburg effect”. Understanding the complex glucose metabolism in CRC cells may support the development of new diagnostic and therapeutic approaches. Here we discuss the most recent findings on genetic mutations and epigenetic modulations that may positively or negatively regulate the Warburg effect in CRC cells. We focus on the non‐coding RNA (ncRNA)‐based epigenetics, and we present a perspective on the therapeutic relevance of critical molecules and ncRNAs mediating the Warburg effect in CRC cells. All the relevant studies were identified and assessed according to the genes and enzymes mediating the Warburg effect. The findings summarized in this review should provide a better understanding of the relevance of genetic mutations and the ncRNA‐based epigenetic alterations to CRC pathogenesis to help overcome chemoresistance.</p

Genetic mutations and non‐coding RNA‐based epigenetic alterations mediating the Warburg effect in colorectal carcinogenesis

Colorectal cancer (CRC) development is a gradual process defined by the accumulation of numerous genetic mutations and epigenetic alterations leading to the adenoma‐carcinoma sequence. Despite significant advances in the diagnosis and treatment of CRC, it continues to be a leading cause of cancer‐related deaths worldwide. Even in the presence of oxygen, CRC cells bypass oxidative phosphorylation to produce metabolites that enable them to proliferate and survive—a phenomenon known as the “Warburg effect”. Understanding the complex glucose metabolism in CRC cells may support the development of new diagnostic and therapeutic approaches. Here we discuss the most recent findings on genetic mutations and epigenetic modulations that may positively or negatively regulate the Warburg effect in CRC cells. We focus on the non‐coding RNA (ncRNA)‐based epigenetics, and we present a perspective on the therapeutic relevance of critical molecules and ncRNAs mediating the Warburg effect in CRC cells. All the relevant studies were identified and assessed according to the genes and enzymes mediating the Warburg effect. The findings summarized in this review should provide a better understanding of the relevance of genetic mutations and the ncRNA‐based epigenetic alterations to CRC pathogenesis to help overcome chemoresistance.</p

SARS-CoV-2 Infection-Induced Promoter Hypomethylation as an Epigenetic Modulator of Heat Shock Protein A1L (HSPA1L) Gene

Numerous researches have focused on the genetic variations affecting SARS-CoV-2 infection, whereas the epigenetic effects are inadequately described. In this report, for the first time, we have identified potential candidate genes that might be regulated via SARS-CoV-2 induced DNA methylation changes in COVID-19 infection. At first, in silico transcriptomic data of COVID-19 lung autopsies were used to identify the top differentially expressed genes containing CpG Islands in their promoter region. Similar gene regulations were also observed in an in vitro model of SARS-CoV-2 infected lung epithelial cells (NHBE and A549). SARS-CoV-2 infection significantly decreased the levels of DNA methyltransferases (DNMT1, DNMT3A, and DNMT3B) in lung epithelial cells. Out of 14 candidate genes identified, the expression of 12 genes was upregulated suggesting promoter hypomethylation, while only two genes were downregulated suggesting promoter hypermethylation in COVID-19. Among those 12 upregulated genes, only HSPA1L and ULBP2 were found to be upregulated in AZA-treated lung epithelial cells and immune cells, suggesting their epigenetic regulation. To confirm the hypomethylation of these two genes during SARS-CoV-2 infection, their promoter methylation and mRNA expression levels were determined in the genomic DNA/RNA obtained from whole blood samples of asymptomatic, severe COVID-19 patients and equally matched healthy controls. The methylation level of HSPA1L was significantly decreased and the mRNA expression was increased in both asymptomatic and severe COVID-19 blood samples suggesting its epigenetic regulation by SARS-CoV-2 infection. Functionally, HSPA1L is known to facilitate host viral replication and has been proposed as a potential target for antiviral prophylaxis and treatment.</p

SARS-CoV-2 Infection-Induced Promoter Hypomethylation as an Epigenetic Modulator of Heat Shock Protein A1L (HSPA1L) Gene

Numerous researches have focused on the genetic variations affecting SARS-CoV-2 infection, whereas the epigenetic effects are inadequately described. In this report, for the first time, we have identified potential candidate genes that might be regulated via SARS-CoV-2 induced DNA methylation changes in COVID-19 infection. At first, in silico transcriptomic data of COVID-19 lung autopsies were used to identify the top differentially expressed genes containing CpG Islands in their promoter region. Similar gene regulations were also observed in an in vitro model of SARS-CoV-2 infected lung epithelial cells (NHBE and A549). SARS-CoV-2 infection significantly decreased the levels of DNA methyltransferases (DNMT1, DNMT3A, and DNMT3B) in lung epithelial cells. Out of 14 candidate genes identified, the expression of 12 genes was upregulated suggesting promoter hypomethylation, while only two genes were downregulated suggesting promoter hypermethylation in COVID-19. Among those 12 upregulated genes, only HSPA1L and ULBP2 were found to be upregulated in AZA-treated lung epithelial cells and immune cells, suggesting their epigenetic regulation. To confirm the hypomethylation of these two genes during SARS-CoV-2 infection, their promoter methylation and mRNA expression levels were determined in the genomic DNA/RNA obtained from whole blood samples of asymptomatic, severe COVID-19 patients and equally matched healthy controls. The methylation level of HSPA1L was significantly decreased and the mRNA expression was increased in both asymptomatic and severe COVID-19 blood samples suggesting its epigenetic regulation by SARS-CoV-2 infection. Functionally, HSPA1L is known to facilitate host viral replication and has been proposed as a potential target for antiviral prophylaxis and treatment.</p

Protein arginine N-methyltransferase 5 in colorectal carcinoma:Insights into mechanisms of pathogenesis and therapeutic strategies

Protein arginine N-methyltransferase 5 (PRMT5) enzyme is one of the eight canonical PRMTs, classified as a type II PRMT, induces arginine monomethylation and symmetric dimethylation. PRMT5 is known to be overexpressed in multiple cancer types, including colorectal cancer (CRC), where its overexpression is associated with poor survival. Recent studies have shown that upregulation of PRMT5 induces tumor growth and metastasis in CRC. Moreover, various novel PRMT5 inhibitors tested on CRC cell lines showed promising anticancer effects. Also, it was suggested that PRMT5 could be a valid biomarker for CRC diagnosis and prognosis. Hence, a deeper understanding of PRMT5-mediated CRC carcinogenesis could provide new avenues towards developing a targeted therapy. In this study, we started with in silico analysis correlating PRMT5 expression in CRC patients as a prelude to further our investigation of its role in CRC. We then carried out a comprehensive review of the scientific literature that dealt with the role(s) of PRMT5 in CRC pathogenesis, diagnosis, and prognosis. Also, we have summarized key findings from in vitro research using various therapeutic agents and strategies directly targeting PRMT5 or disrupting its function. In conclusion, PRMT5 seems to play a significant role in the pathogenesis of CRC; therefore, its prognostic and therapeutic potential merits further investigation.</p

Luteolin inhibits proliferation, triggers apoptosis and modulates Akt/mTOR and MAP kinase pathways in HeLa cells

Flavonoids, a subclass of polyphenols, have been shown to be effective against several types of cancer, by decreasing proliferation and inducing apoptosis. Therefore, the aim of the present study was to assess the anti-carcinogenic potential of luteolin on HeLa human cervical cancer cells, through the use of a cell viability assay, DNA fragmentation assay, mitochondrial membrane potential assay, cell cycle analysis using Annexin/PI staining and flow cytometry, gene expression analysis and a protein profiling array. Luteolin treatment exhibited cytotoxicity towards HeLa cells in a dose- and time-dependent manner, and its anti-proliferative properties were confirmed by accumulation of luteolin-treated cells in sub-G1 phases. Cytotoxicity induced by luteolin treatment resulted in apoptosis, which was mediated through depolarization of the mitochondrial membrane potential and DNA fragmentation. Furthermore, luteolin treatment increased the expression of various proapoptotic genes, including APAF1, BAX, BAD, BID, BOK, BAK1, TRADD, FADD, FAS, and Caspases 3 and 9, whereas the expression of anti-apoptotic genes, including NAIP, MCL-1 and BCL-2, was decreased. Cell cycle regulatory genes, including CCND1, 2 and 3, CCNE2, CDKN1A, CDKN2B, CDK4 and CDK2, were decreased following treatment. Expression of TRAILR2/DR5, TRAILR1/DR4, Fas/TNFRSF6/CD95 and TNFR1/TNFRSF1A, as well as pro-apoptotic proteins, including BAD, BAX and Cytochrome C were consistently increased, and the expression of antiapoptotic proteins, HIF1α, BCL-X, MCL1 and BCL2, were found to be decreased following treatment. Expression of AKT1 and 2, ELK1, PIK3C2A, PIK3C2B, MAPK14, MAP3K5, MAPK3 and MAPK1 was significantly decreased at the transcriptional level. Expression of GSK3b (p-ser9), PRAS 40 (p-Ther246), BAD (p-ser112), PTEN (p-ser380), AKT (p-ser473), ERK2 (p-Y185/Y187), RISK2 (p-ser386), P70S6k (p-Thr421/ser424), PDK1(p-ser241), ERK1 (p-T202/Y204) and MTOR (p-ser2448) was downregulated and expression of P53 (p-ser241) and P27(p-Thr198) was upregulated by luteolin in a dose-dependent manner, indicating its anti-proliferative and apoptosis enabling properties, and this may have been mediated via inhibition of the AKT and the MAPK pathways. © 2021 Spandidos Publications. All rights reserved

PRMT5 Mediated HIF1α Signaling and Ras-Related Nuclear Protein as Promising Biomarker in Hepatocellular Carcinoma

Protein arginine N-methyltransferase 5 (PRMT5) has been identified as a potential therapeutic target for various cancer types. However, its role in regulating the hepatocellular carcinoma (HCC) transcriptome remains poorly understood. In this study, publicly available databases were employed to investigate PRMT5 expression, its correlation with overall survival, targeted pathways, and genes of interest in HCC. Additionally, we utilized in-house generated NGS data to explore PRMT5 expression in dysplastic nodules compared to hepatocellular carcinoma. Our findings revealed that PRMT5 is significantly overexpressed in HCC compared to normal liver, and elevated expression correlates with poor overall survival. To gain insights into the mechanism driving PRMT5 overexpression in HCC, we analyzed promoter CpG islands and methylation status in HCC compared to normal tissues. Pathway analysis of PRMT5 knockdown in the HCC cells revealed a connection between PRMT5 expression and genes related to the HIF1α pathway. Additionally, by filtering PRMT5-correlated genes within the HIF1α pathway and selecting up/downregulated genes in HCC patients, we identified Ras-related nuclear protein (RAN) as a target associated with overall survival. For the first time, we report that PRMT5 is implicated in the regulation of HIF1A and RAN genes, suggesting the potential prognostic utility of PRMT5 in HCC.</p