The Relationship between the Methylation of RASSF1A、MGMT、DAPK、p16、RARβ and the Sensitivity to Cisplatin in A549 Cell Line

Abstract: It was reported that the changes of multiple gene expression regulated by the methylation might be one of regulation factor in the sensitivity to chemotherapy. In order to search for the biomarker for the sensitivity to cisplatin in lung cancer， A549 cell line and its homologous cisplatin-resistant cell line (A549-DDP) were cultured. Methylation specific PCR (MSP) was used to detect the methylation status of 5 candidate gene (RASSF1A， MGMT， DAPK， p16， RARβ). RT-PCR was used to detect the mRNA expression of these 5 genes among the two cell lines. The results indicated， in A549 cell line， RASSF1A， MGMT， p16 were unmethylated and high expressed， and the three genes were hypermethylated and low expressed in A549-DDP cell line， but unmethylated status and high level of mRNA expression of RARβ gene were found in A549-DDP only， and there was no difference in the methylation and expression of DAPK. Treated with demethylating agent (5-aza-CdR)， the mRNA expression of those three hypermethylation gene (RASSF1A， MGMT， p16) in A549-DDP was upregulated， the effect was dependent on the concentration of 5-aza-CdR and the time duration. The present study indicated that the mRNA changes regulated by the methylation of RASSF1A， MGMT， p16， RARβ might be the possible reason for A549’s sensitivity to cisplatin. As a potential biomarker for the sensitivity to cisplatin， the methylation panel of RASSF1A， MGMT， p16， RARβ in lung cancer is deserved to be further investigated in clinic.

CSTR: 32200.14.cjcb.2011.12.0006