Apoptosis Induced by Prednisolone Occurs without Altering the Promoter Methylation of BAX and BCL-2 Genes in Acute Lymphoblastic Leukemia Cells CCRF-CEM.

OBJECTIVE: one of the main mechanisms in which cancer cells are resistant to chemotherapy drugs and therapeutic strategies is resistance to apoptosis due to these anticancer factors. Regulating the expression of genes through epigenetics, especially regulation through methylation, is one of the key aspects of regulating gene expression and the function of genes, which is also regulated by the pathways regulating the pathway of apoptosis. The epigenetic regulatory phenomenon in cancer cells can undergo a change in regulation and induces resistance to apoptosis against chemotherapy and anticancer factors. The purpose of the present scrutiny was defined to probe the effect of subtoxic prednisolone dose on the level of promoter methylation and gene expression of BAX and BCL2 in the CCRF-CEM cells. METHODS: The treated cells by prednisolone, cultured in RPMI 1640 medium in standard condition. Alteration in promoter DNA methylation was analyzed by use of methylation specific-PCR (MSP) technique after the defined intervened time of Prednisolone treatment with a subtoxic dose. RESULTS: Prednisolone can induce apoptosis via alteration in BAX and BCL2 genes, based on our previous scrutiny. This essay shows no varies in the Pattern of DNA methylation of examined genes; however, prednisolone changes the expression of examined genes. CONCLUSION: Lack of alteration through prednisolone treatment in DNA methylation template of BAX and BCL2 genes make this possible that Prednisolone affects apoptotic gene expression via different pathways, which need more research to be done about it.
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Epigenetic mechanisms are behind the regulation of the key genes associated with the osteoblastic differentiation of the mesenchymal stem cells: The role of zoledronic acid on tuning the epigenetic changes.

Mesenchymal stem cells (MSCs) are multipotent stem cells and show distinct features such as capability for self-renewal and differentiation into several lineages of cells including osteoblasts, chondrocytes, and adipocytes. In this study, the methylation status of the promoter region of zinc finger and BTB domain containing 16 (ZBTB16), twist-related protein 1(Twist1), de novo DNA methyltransferases 3A (DNMT3A), SRY-box 9 (Sox9), osteocalcin (OCN), and peroxisome proliferator-activated receptor γ2 (PPARγ2) genes and their messenger RNA (mRNA) expression levels were evaluated during the osteoblastic differentiation of MSCs (ODMSCs). We planned two experimental groups including zoledronic acid (ZA)-treated and nontreated cells (negative control) which both were differentiated into the osteoblasts. Methylation level of DNA in the promoter regions was assayed by methylation-specific-quantitative polymerase chain reaction (MS-qPCR), and mRNA levels of the target inhibitory/stimulatory genes during osteoblastic differentiation of MSCs were measured using real-time PCR. During the experimental induction of ODMSCs, the mRNA expression of the OCN gene was upregulated and methylation level of its promoter region was decreased. Moreover, Sox9 and PPARγ2 mRNA levels were attenuated and their promoter regions methylation levels were significantly augmented. However, the mRNA expression of the DNMT3A was not affected during the ODMSCs though its methylation rate was increased. In addition, ZA could enhance the expression of the ZBTB16 and decrease its promoter regions methylation and on the opposite side, it diminished mRNA expression of Sox9, Twist1, and PPARγ2 genes and increased their methylation rates. Intriguingly, ZA did not show a significant impact on gene expression and methylation levels the OCN and DNMT3A. We found that methylation of the promoter regions of Sox9, OCN, and PPARγ2 genes might be one of the main mechanisms adjusting the genes expression during the ODMSCs. Furthermore, we noticed that ZA can accelerate the MSCs differentiation to the osteoblast cells via two regulatory processes; suppression of osteoblastic differentiation inhibitor genes including Sox9, Twist1, and PPARγ2, and through promotion of the ZBTB16 expression.

Altered T-cell subpopulations in recurrent pregnancy loss patients with cellular immune abnormalities.

Recurrent pregnancy loss (RPL) is a multifactorial disorder of women in reproductive age, which in some cases is caused by immunologic abnormalities. In this study, we aimed to evaluate cellular and molecular components of the immune system like different T-cell subsets and their regulating microRNAs (miRNAs) in RPL women and control group. Fifty RPL and 50 healthy subjects were recruited. Subsets of T cells, including regulatory T (Treg) cells, helper T (Th) 17 cells, exhausted T cells, exhausted Treg cells were evaluated by flow cytometry. Transcription factors of T cells and related miRNA profile were quantified using real-time polymerase chain reaction (RT-PCR). Assessment showed that Treg and exhausted T cells, were decreased in RPL patients (p = 0.009 and 0.02, respectively), while an increase was observed in Th17 and exhausted Treg frequency ( p = 0.013 and 0.0037, respectively). Messenger RNA expression level of T-bet and IRF4 was upregulated in RPL patients ( p = 0.011 and 0.0001, respectively), while Th2- and Treg-related transcription factors, GATA3 and GITR, were downregulated in these patients compared with the healthy subjects ( p = 0.0008 and <0.000, respectively). Treg-associated miRNAs, the miR-106b-25-93 cluster, showed a higher rate in RPL patients ( P = 0.007, 0.001, and 0.029, respectively), however, we observed no significant difference in the expression level of Th17-associated miRNA, mir-326. According to the results, we concluded that unbalanced immune responses and deregulated function of T-cell subsets may lead to reproduction-related failure like a miscarriage. Therefore, evaluation of immune cells and related miRNA profile may serve as prognostic biomarker for the treatment of RPL patients.

Apoptotic effect of resveratrol on human T-ALL cell line CCRF-CEM is unlikely exerted through alteration of BAX and BCL2 promoter methylation.

One of the fundamental barriers leading to failure of leukemia therapy is the resistance against conventional chemotherapies, common modality used to cure leukemia. Having the potential to trigger apoptosis in various human leukemia cell lines, resveratrol is regarded as a robust agent in chemotherapy regimens. The current study was aimed to assess whether the apoptotic effect of resveratrol on T-cell acute lymphoblastic leukemia cell line, CCRF-CEM, is exerted through DNA methylation of BAX and BCL2 gene promoters. For this purpose, the CCRF-CEM cells were treated by resveratrol under standard cell culture. To analyze the promoter DNA methylation changes, we used methylation-specific polymerase chain reaction technique following the resveratrol treatment at different dosages and time intervals. Based on our previous study, the resveratrol treatment can trigger apoptosis in CCRF-CEM cell line via upregulation of apoptotic BAX gene and downregulation of antiapoptotic BCL2 gene. Despite these alterations in gene expression, the current study reveals no changes in DNA methylation patterns of subjected genes following the resveratrol treatment. Unchanged status of DNA methylation of BAX and BCL2 genes may suggest that resveratrol causes the gene expression changes through a distinct mechanism which requires further studies to be understood.

Aberrant methylated EDNRB can act as a potential diagnostic biomarker in sporadic colorectal cancer while KISS1 is controversial.

Cancers are among the most serious threats of human health worldwide. Survival and mortality rates of colorectal cancer (CRC) strongly depend on the early diagnosis. The aberrant methylation pattern of genes as a diagnostic biomarker can serve as a practical option for timely detection and contribute subsequently to the enhancement of survival rate in CRC patients, since methylation changes are not only frequent but also can occur in initial tumorogenesis stages. It has been indicated that EDNRB and KISS1 genes are hypermethylated through progression and development of CRC. In current study, after extraction of genomic DNA from 45 paired tumor and adjacent non-cancerous tissue samples and treatment with bisulfite conversion, the methylation status of EDNRB and KISS1 CpG rich regions were assessed quantitatively using MS-HRM assay to determine practicability of these aberrant methylations for diagnosis of sporadic CRC and its discrimination from corresponding normal tissues. The results showed that the methylation distribution differences, comparing tumor tissues with their adjacent non-cancerous tissues, were statistically significant in all selected locations within EDNRB gene promoter (P < 0.001); they had also some correlations with tumor stage and grade. Nonetheless, methylation distribution in KISS1 gene CpG rich region revealed no statistically significant differences between CRC and adjacent non-cancerous tissues (P = 0.060). Overall, it can be concluded that aberrant methylated EDNRB can be a promising potential diagnostic biomarker for CRC, while KISS1 is controversial and needs to be more investigated.

Detection of aberrant methylated SEPT9 and NTRK3 genes in sporadic colorectal cancer patients as a potential diagnostic biomarker.

Colorectal cancer (CRC) is one of the most common malignancies, and the third leading cause of cancer mortality worldwide. Timely detection of CRC in patients with earlier stages provides the highest rate of survival. Epigenetic alterations are important in the occurrence and progression of CRC, and represent the primary modifications of cancer cells. Therefore, detection of these alterations in CRC cases are thought to hold great promise as diagnostic biomarkers. It has been shown that the SEPT9 and NTRK3 genes are aberrantly methylated and their detection can be used as biomarkers for early diagnosis of CRC. The present study analyzed promoter methylation status of these genes in CRC patients. Genomic DNA was extracted from 45 CRC and paired adjacent healthy tissues and undergone bisulfite conversion, and the methylation status of NTRK3 and SEPT9 were defined using the MS-HRM assay. Our results showed that there are statistically significant differences in methylation status of NTRK3 and specially SEPT9 between CRC and adjacent normal tissues (P<0.001). High sensitivity and specificity for a specific location in SEPT9 gene promoter as a diagnostic biomarker was observed. SEPT9 promoter hypermethylation may serve as a promising biomarker for the detection of CRC development. However, to validate the biomarker potential of NTRK3 there is a requirement for further investigation.