Acitretin induces apoptosis and changes of relative signaling pathway in epidermoid carcinoma cell line A431 / 浙江大学学报·医学版

ABSTRACT

<p><b>OBJECTIVE</b>To study the effects of Acitretin on growth inhibition and apoptosis of epidermoid carcinoma cell line A431 and its molecular mechanisms.</p><p><b>METHODS</b>A431 cells were treated with Acitretin at the concentration of 10(-5)mol/L in different time intervals. The inhibition of cell growth was determined by MTT method, morphological changes were observed by electron microscopy, apoptosis was assessed by flow cytometry and Annexin-V staining. The mRNA expression levels of STAT3, cyclinD1 and p42/44MAPK were detected by reverse transcriptase polymerase chain reaction (RT-PCR). The protein expression levels of P-STAT3 and CyclinD1 were observed by Western blot in A431 cells.</p><p><b>RESULT</b>(1)Acitretin inhibited the growth of A431 cells in vitro in a dose-and time-dependent manner. Morphological changes revealed characteristics of cell apoptosis. Flow cytometry showed more sub-G(1) phase in A431 cells and more cells positively stained with Annexin-V. (2)Acitretin significantly inhibited the expression of STAT3 and CyclinD1 mRNA in A431 cells in vitro in a time-dependent manner(P<0.05). The p-STAT3 and CyclinD1 protein levels were down regulated. The Acitretin could also down regulate the p42/4MAPK mRNA in A431 cells. (3) After incubation with Acitretin, the mRNA level of CyclinD1 in A431 cells was positively correlated with that of STAT3(p<0.05). The protein level of CyclinD1 was also positively correlated with that of p-STAT3(p<0.05). However, there was no correlation between Mrna levels of CyclinD1 and p42/44MAPK.</p><p><b>CONCLUSION</b>(1)Acitretin plays an inhibitory role in the tumor cell growth and induces the cell apoptosis in A431 cells. (2)The regulation of the Jak/STAT3 signaling pathway may play an important role in inducing growth inhibition and apoptosis by Acitretin in A431 cells.</p>