Similar Datasets
Project description:Histone deacetylase inhibitors (HDACi) are part of a growing class of epigenetic therapies used for the treatment of cancer. Although HDACis are effective in the treatment of T-cell lymphomas, treatment of solid tumors with this class of drugs has not been successful. Overexpression of the multidrug resistance protein P-glycoprotein (P-gp), encoded by ABCB1, is known to confer resistance to the HDACi romidepsin in vitro, yet increased ABCB1 expression has not been associated with resistance in patients, suggesting that other mechanisms of resistance arise in the clinic. To identify alternative mechanisms of resistance to romidepsin, we selected MCF-7 breast cancer cells with romidepsin in the presence of the P-gp inhibitor verapamil to reduce the likelihood of P-gp-mediated resistance. The resulting cell line, MCF-7 DpVp300, does not express P-gp and was found to be selectively resistant to romidepsin but not to other HDACis such as belinostat, panobinostat, or vorinostat. RNA-sequencing analysis revealed upregulation of the mRNA coding for the putative methyltransferase, METTL7A, whose paralog, METTL7B, was previously shown to methylate thiol groups on hydrogen sulfide and captopril. As romidepsin has a thiol as the zinc-binding moiety, we hypothesized that METTL7A could inactivate romidepsin and other thiol-based HDACis via methylation of the thiol group. We demonstrate that expression of METTL7A or METTL7B confers resistance to thiol-based HDACis and that both enzymes are capable of methylating thiol-containing HDACis. We thus propose that METTL7A and METTL7B confer resistance to thiol-based HDACis by methylating and inactivating the zinc-binding thiol.
| S-EPMC11223745 | biostudies-literature
Project description:Histone deacetylase inhibitors (HDI) are among the growing class of epigenetic therapies used for the treatment of cancer. Although histone deacetylase inhibitors (HDIs) are effective in the treatment of T-cell lymphomas, solid tumors are largely resistant, and few mechanisms of resistance have been described. Overexpression of the multi-drug resistance gene ABCB1 that encodes P-glycoprotein (P-gp) is known to confer resistance to the HDI romidepsin, yet it is not associated with resistance in patients, suggesting other mechanisms of resistance arise in patients. To identify alternative romidepsin resistance mechanisms, we selected MCF-7 breast cancer cells with romidepsin in the presence of verapamil to reduce the chance of P-gp over-expression developing as a resistance mechanism. The resulting subline, MCF-7 DpVp300, does not express P-gp and was found to be selectively resistant to romidpesin but not other HDIs such as belinostat, panobinostat, or vorinostat. RNA sequencing analysis demonstrated upregulation of the putative methyltransferase, METTL7A, a paralog of which, METTL7B, was found to methylate thiol groups on hydrogen sulfide and captopril. We hypothesized that METTL7A could methylate and inactivate romidepsin as well as other HDIs with a thiol as the zinc binding group. Here we show that expression of METTL7A is necessary for thiol-based HDI resistance in the MCF-7 DpVp300 cell line, and that expression of METTL7A or METTL7B in sensitive cells confers resistance to thiol based HDIs. We thus propose that METTL7A and METTL7B confer resistance to thiol-based HDIs by methylating and inactivating the zinc-binding thiol.
2025-05-13 | GSE217128 | GEO
Project description:Histone deacetylase inhibitors (HDI) are among the growing class of epigenetic therapies used for the treatment of cancer. Although histone deacetylase inhibitors (HDIs) are effective in the treatment of T-cell lymphomas, solid tumors are largely resistant, and few mechanisms of resistance have been described. Overexpression of the multi-drug resistance gene ABCB1 that encodes P-glycoprotein (P-gp) is known to confer resistance to the HDI romidepsin, yet it is not associated with resistance in patients, suggesting other mechanisms of resistance arise in patients. To identify alternative romidepsin resistance mechanisms, we selected MCF-7 breast cancer cells with romidepsin in the presence of verapamil to reduce the chance of P-gp over-expression developing as a resistance mechanism. The resulting subline, MCF-7 DpVp300, does not express P-gp and was found to be selectively resistant to romidpesin but not other HDIs such as belinostat, panobinostat, or vorinostat. RNA sequencing analysis demonstrated upregulation of the putative methyltransferase, METTL7A, a paralog of which, METTL7B, was found to methylate thiol groups on hydrogen sulfide and captopril. We hypothesized that METTL7A could methylate and inactivate romidepsin as well as other HDIs with a thiol as the zinc binding group. Here we show that expression of METTL7A is necessary for thiol-based HDI resistance in the MCF-7 DpVp300 cell line, and that expression of METTL7A or METTL7B in sensitive cells confers resistance to thiol based HDIs. We thus propose that METTL7A and METTL7B confer resistance to thiol-based HDIs by methylating and inactivating the zinc-binding thiol.
2025-05-13 | GSE217127 | GEO
Project description:Histone deacetylase inhibitors (HDI) are among the growing class of epigenetic therapies used for the treatment of cancer. Although histone deacetylase inhibitors (HDIs) are effective in the treatment of T-cell lymphomas, solid tumors are largely resistant, and few mechanisms of resistance have been described. Overexpression of the multi-drug resistance gene ABCB1 that encodes P-glycoprotein (P-gp) is known to confer resistance to the HDI romidepsin, yet it is not associated with resistance in patients, suggesting other mechanisms of resistance arise in patients. To identify alternative romidepsin resistance mechanisms, we selected MCF-7 breast cancer cells with romidepsin in the presence of verapamil to reduce the chance of P-gp over-expression developing as a resistance mechanism. The resulting subline, MCF-7 DpVp300, does not express P-gp and was found to be selectively resistant to romidpesin but not other HDIs such as belinostat, panobinostat, or vorinostat. RNA sequencing analysis demonstrated upregulation of the putative methyltransferase, METTL7A, a paralog of which, METTL7B, was found to methylate thiol groups on hydrogen sulfide and captopril. We hypothesized that METTL7A could methylate and inactivate romidepsin as well as other HDIs with a thiol as the zinc binding group. Here we show that expression of METTL7A is necessary for thiol-based HDI resistance in the MCF-7 DpVp300 cell line, and that expression of METTL7A or METTL7B in sensitive cells confers resistance to thiol based HDIs. We thus propose that METTL7A and METTL7B confer resistance to thiol-based HDIs by methylating and inactivating the zinc-binding thiol.
2025-05-13 | GSE217129 | GEO
Project description:The methyltransferases METTL7A and METTL7B confer resistance of cancer cells to thiol-based histone deacetylate inhibitors
| PRJNA896986 | ENA
Project description:The methyltransferases METTL7A and METTL7B confer resistance of cancer cells to thiol-based histone deacetylate inhibitors (ATAC-Seq)
| PRJNA896984 | ENA
Project description:The methyltransferases METTL7A and METTL7B confer resistance of cancer cells to thiol-based histone deacetylate inhibitors (RNA-Seq)
| PRJNA896981 | ENA
Project description:The methyltransferases METTL7A and METTL7B confer resistance of cancer cells to thiol-based histone deacetylate inhibitors (Mnase-Seq)
| PRJNA896983 | ENA
Project description:Methylation of DNA and histone proteins are mutually involved in the epigenetic regulation of gene expression mediated by DNA methyltransferases (DNMTs) and histone methyltransferases (HMTs). DNMTs methylate cytosine residues within gene promoters, whereas HMTs catalyze the transfer of methyl groups to lysine and arginine residues of histone proteins, thus causing chromatin condensation and transcriptional repression, which play an important role in the pathogenesis of cancer. The potential reversibility of epigenetic alterations has encouraged the development of dual pharmacologic inhibitors of DNA and histone methylation as anticancer therapeutics. Dietary flavones can affect epigenetic modifications that accumulate over time and have shown anticancer properties, which are undefined. Through DNA binding and in silico protein-ligand docking studies with plant flavones viz. Apigenin, Chrysin and Luteolin, the effect of flavones on DNA and histone methylation was assessed. Spectroscopic analysis of flavones with calf-thymus DNA revealed intercalation as the dominant binding mode, with specific binding to a GC-rich sequence in the DNA duplex. A virtual screening approach using a model of the catalytic site of DNMT and EZH2 demonstrated that plant flavones are tethered at both ends inside the catalytic pocket of DNMT and EZH2 by means of hydrogen bonding. Epigenetic studies performed with flavones exhibited a decrease in DNMT enzyme activity and a reversal of the hypermethylation of cytosine bases in the DNA and prevented cytosine methylation in the GC-rich promoter sequence incubated with the M.SssI enzyme. Furthermore, a marked decrease in HMT activity and a decrease in EZH2 protein expression and trimethylation of H3K27 were noted in histones isolated from cancer cells treated with plant flavones. Our results suggest that dietary flavones can alter DNMT and HMT activities and the methylation of DNA and histone proteins that regulate epigenetic modifications, thus providing a significant anticancer effect by altering epigenetic processes involved in the development of cancer.
| S-EPMC5033486 | biostudies-literature
Project description:Gastric cancer (GC) is one of the most frequent tumors in the world. Stomach adenocarcinoma is a heterogeneous tumor, turning the prognosis prediction and patients' clinical management difficult. Some diagnosis tests for GC are been development using knowledge based in polymorphisms, somatic copy number alteration (SCNA) and aberrant histone methylation. This last event, a posttranslational modification that occurs at the chromatin level, is an important epigenetic alteration seen in several tumors including stomach adenocarcinoma. Histone methyltransferases (HMT) are the proteins responsible for the methylation in specific amino acids residues of histones tails. Here, were presented several HMTs that could be relating to GC process. We use public data from 440 patients with stomach adenocarcinoma. We evaluated the alterations as SCNAs, mutations, and genes expression level of HMTs in these aforementioned samples. As results, it was identified the 10 HMTs most altered (up to 30%) in stomach adenocarcinoma samples, which are the PRDM14, PRDM9, SUV39H2, NSD2, SMYD5, SETDB1, PRDM12, SUV39H1, NSD3, and EHMT2 genes. The PRDM9 gene is among most mutated and amplified HMTs within the data set studied. PRDM14 is downregulated in 79% of the samples and the SUV39H2 gene is down expressed in patients with recurred/progressed disease. Several HMTs are altered in many cancers. It is important to generate a genetic atlas of alterations of cancer-related genes to improve the understanding of tumorigenesis events and to propose novel tools of diagnosis and prognosis for the cancer control.
| S-EPMC8369960 | biostudies-literature