雄激素非依赖性前列腺癌耐药转化过程中异常甲基化基因的鉴定

Identification of Aberrant Methylation Genes in the Process of Drug Resistance Transformation of Androgen Independent Prostate Cancer

目的探讨DNA甲基化在雄激素非依赖性前列腺癌耐药转变过程中的作用。方法以雄激素依赖性前列腺癌LNCa P细胞为对照组,雄激素非依赖性前列腺癌细胞LNCa P-AI为实验组,采用Illumina DNA甲基化芯片检测两组细胞基因组DNA甲基化水平,并对甲基化芯片数据进行生物信息学分析;实时荧光定量RT-PCR检测前列腺特异抗原PSA mRNA的相对表达量。结果 LNCa P细胞相比,发现LNCa P-AI细胞共有2619个基因甲基化水平发生改变,其中758个基因发生高甲基化,占差异基因的28.9%,1860个基因表现为低甲基化,占差异基因的71.1%,这些差异甲基化基因涉及Notch信号通路和胰岛素样生长因子1信号通路。LNCa P-AI细胞PSA基因甲基化水平上升了3.67倍,其PSA mRNA表达水平下调了6.5倍。结论DNA甲基化参与了前列腺癌雄激素非依赖性转变的过程,可能是导致前列腺癌耐药的诱因之一。

Objective To investigate the role of DNA methylation in the process of drug resistance in the androgen independent prostate cancer. Methods The androgen dependent prostate cancer LNCaP cells were chosen as the control group. The androgen independent prostate cancer cell LNCaP - AI was chosen as the experimental group. Genomie DNA methylation levels in the two groups were detected by DNA Illumina methylation mieroarray, DNA methylation microarray data was analyzed by bioinformatics methods. The relative expression of prostate specific antigen mRNA was detected by real time fluorescent quantitative RT - PCR assay. Results LNCaP - AI cells were found to have a total of 2619 gene methylation levels change in contrast to LNCaP cells. Totally 758 of these genes were highly methylated, accounting for 28.9% of the difference. Totally 1860 genes showed low methylation, accounting for 71.1% of the difference. These genes involved in Notch signaling pathway and insulin like growth factor 1 signaling pathway. PSA gene methylation level of PSA cells increased by 3.67 times, and the expression level of mRNA LNCaP - AI was down regulated by 6.5 times. Conclusion DNA methylation is involved in the process of androgen independent transition of prostate cancer, which may be one of the causes of prostate cancer drug resistance.