| Abstract |
Tumor suppressor genes silenced by CpG methylation uncover the molecular mechanism of tumorigenesis and potential tumor biomarkers. Our previous research found that the promoter of zinc-finger protein 82 (ZFP82) was highly methylated in multiple cancers, including esophageal cancer, which induces the occurrence and development of tumors. Here, we describe the frequent detection of methylation of the ZFP82 promoter CpG Island in patients who did not respond to neoadjuvant chemotherapy, indicating that ZFP82 may related to esophageal cancer chemo-resistance. We further verified that in esophageal cancer cells expressing wild-type p53, ZFP82 bound to the HDAC3 promoter and mediated its interaction with p53, leading to HDAC3 cleavage and reduction of p53 ubiquitin-dependent proteasomal degradation, thus enhancing wild-type p53 stability. In cells expressing mutant p53, ZFP82 interacted with HDAC3 to regulate the down-regulation of HSP 70, leading to degradation of mutant p53. Through both mechanisms, the restoration of ZFP82 enhanced the chemosensitivity in esophageal cancer cells expressing wild-type p53 or mutant p53, significantly inhibiting in vivo tumorigenicity of these cells. Analyses of the expression of ZFP82 and clinical data indicated that ZFP82 expression correlated with improved prognosis. Our results define a mechanism for p53 stabilization via ZFP82-dependent HDAC3 decay under genotoxic stress conditions and validate a candidate bio-marker of early prediction of patients who will respond to esophageal cancer neoadjuvant chemotherapy.
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