葎草酮对人胃癌细胞SGC-7901 N-乙酰基转移酶1活性及基因表达的抑制作用

Inhibition of humulon on arylamine N-acetyltransferase-1 activity and gene expression in SGC-7901 cells

目的探讨葎草酮抗肿瘤作用以及其与N-乙酰基转移酶1(NAT1酶)之间的关系。方法采用HPLC法,以对氨基苯甲酸(PABA)为底物,测定PABA被NAT1乙酰化为乙酰化对氨基苯甲酸(Ac-PABA)的量,间接反映NAT1酶的活性。采用RT-PCR法,测定葎草酮对NAT1mRNA表达的影响。结果葎草酮能够显著降低SGC-7901完整细胞和细胞质中Ac-PABA的生成量;随着作用时间的增加,Ac-PABA的生成量逐渐增加,但与其相同时间点的阴性对照组比较,葎草酮组Ac-PABA的生成量明显减少;葎草酮能够降低SGC-7901细胞中NAT1 mRNA的表达。结论葎草酮通过抑制NAT1的活性和基因表达两个方面减少芳香胺类化合物代谢为乙酰化的芳香胺类致癌物的量,从而预防癌症的发生,防止癌症的进一步恶化。

Objective To study the anti-tumor effects of humul on on arylamine N-acetyltransferase-1 （NAT1） activity. Methods Employing HPLC, using PABA as substrate, in intact SGC-7901 cells and their cytoplasm, making PABA being acetylated to Ac-PABA by NAT1 as the activity of NAT1. Reverse transcriptase polymerase chain reaction （RT-PCR） assay was used to study the expression of the NAT1 mRNA. Results The results show that humulon could inhibit the production of Ac-PABA in intact SGC-7901 cell and the cytoplasm, the production of Ac-PABA was gradually increased with the interaction time increasing. But comparing with corresponding negative control group′s, the production of Ac-PABA was decreased evidently and the humulone could inhibit the expression of NAT1 mRNA. Conclusion Humulon could prevent the occurrence and deterioration of cancer. Its mechanisms can be attributed to its effect on decreasing the production of acetylation of carcinogenic aromatic amines, which is acetylated from aromatic amines, and inhibiting the NAT1 activity and expression of NAT1 mRNA.