抑癌基因p16对维A酸诱导肺癌细胞分化作用的影响

目的探讨抑癌基因p16在维A酸(RA)对肺癌细胞的增殖抑制和分化调控过程中的作用.方法运用基因转染技术将抑癌基因p16转入人肺癌细胞A549中,进而以浓度为5×10-6mol/L的全反式维A酸(ATRA)处理转染和未转染p16基因的肺癌A549细胞1～4d,观察A549细胞生长,流式细胞仪进行细胞周期分析,应用免疫组化分析肺组织分化标志物粘蛋白(MUC1)的变化,同时Westernblot观察ATRA对P16蛋白表达的影响.结果转染p16抑癌基因的A549肺癌细胞经ARTA处理后,细胞增殖能力明显下降,更多的细胞被阻滞于G1/G0期,MUC1的表达下调,Westernblot表明经ATRA处理后P16蛋白表达增加.结论抑癌基因p16能协同RA抑制肺癌A549细胞的恶性增殖及诱导其分化.

Influence of suppressor gene p16 on retinoic acid inducing lmg cancer cell A549 differentiation

OBJECTIVE: To investigate the role of suppressor gene p16 in the process of differential regulation of retinoic acid (RA) on the A549 lung cancer cells. METHODS: Tumor suppressor gene p16 was transfered into A549 cells and the cells were treated with all-trans retinoic acid (ATRA) at the dosage of 5 x 10(-6) mol/L for 4 d. After that, the proliferation and differentiation of A549 cells were examined by growth curve and cytometry analysis, the change of lung lineage-specific marker MUC1 was tested by immunohistochemical staining. Meanwhile, Western blot was used to observe the change of p16 protein expression in A549 cells treated with ATRA. RESULTS: ATRA could obviously inhibit the growth and induce the differentiation of A549 cells that were transfered with p16 gene. There were more cells arrested in G1/G0 phase and the expression of MUC1 was markedly down-regulated than in control cells. The expression of p16 protein was up-regulated in A549 cells treated with ATRA. CONCLUSION: Suppressor gene p16 could enhance the effects of RA on proliferative suppression and differential induction of A549 cells.