ObjectiveTo explore the clinical significance of promoter hypermethylation of O6-methylguanine-DNA methyltransferase (MGMT) in cholangiocarcinoma. MethodsPromoter methylation status of MGMT gene and expression of MGMT protein were detected in cholangiocarcinoma by methylationspecific PCR and immunohistochemical staining, respectively. ResultsAberrant methylation of MGMT gene was detected in 17 patients (47.2%). Twentyone cases showed negative immunoreactivities. Of 21 patients with negative MGMT expression, 14 patients had aberrant methylation of MGMT gene. In 15 patients with positive MGMT expression, aberrant methylation of MGMT gene was only found in three cases. There was a negative correlation between promoter methylation status of MGMT gene and the expression of MGMT protein (rs=-0.816, Plt;0.05). Promoter methylation status of MGMT gene was related to depth of invasion, degree of differentiation, and TNM stage (Plt;0.05), but not to age of patient, gender, pathological type, and lymph node metastasis (Pgt;0.05). ConclusionsHypermethylation of MGMT promoter is a frequency molecular event in cholangiocarcinoma and may be involved in carcinogenesis. Methylation status of MGMT gene may be used to evaluate malignant degree of cholangiocarcinoma.
ObjectiveTo summarize the therapeutic targets of pancreatic cancer (PC). MethodsThe related literatures about the therapeutic targets of PC were reviewed. ResultsPC was one of the most challenging tumor in worldwide, and was characterized as a highly aggressive disease with poor overall prognosis and a high mortality rate. The hallmark of PC was its poor response to radio-and chemo-therapy. Current chemotherapeutic regimens could not provide substantial survival benefit with a clear increase in overall survival. Recently, several new approaches which could significantly improve the clinical outcome of PC had been described, involving signal-transduction pathways, immune response, stroma reaction, and epigenetic changes. ConclusionsMany therapeutic targets are involved in the treatment of PC. As current therapies failed to significantly improve the progression and the survival of PC, new therapeutic approaches and clinical studies are strongly required.
Recent advances in epigenetics indicate that several epigenetic modifications, including acetylation, methylatio, and microRNA (miRNA), play an important role in the pathogenesis of acute kidney injury (AKI). Our study reveales that enhancement of protein acetylation by pharmacological inhibition of class I histone deacetylases leads to more severe tubular injury, and delays the restoration of renal structure and function. The changes in promoter DNA methylation occurs in the kidney with ischemia/reperfusion. MiRNA expression is associated with the regulation of both renal injury and regeneration after AKI. Targeting the epigenetic process may provide a therapeutic treatment for patients with AKI. The purpose of this review is to summarize recent advances in epigenetic regulation of AKI and provide mechanistic insight into the role of acetylation, methylation, and miRNA expression in the pathological processes of AKI.