The mechanisms of the apoptosis of pancreatic cancer cells induced by all-trans retinoic acid

Objective The aim of this study was to observe the effects of all trans retinoic acid (ATRA) on cell growth in vitro and the signal pathway during apoptosis of pancreatic cancer cells induced by ATRA. Methods Pancreatic adenocarcinoma cell line Patu 8988 cells were treated by ATRA. Apoptosis was detected by flow cytometry, DNA degradation assay and TUNEL respectively, and the exprssion of p53 and bcl 2/bax mRNA was assessed by RT PCR, and bcl 2, bax and phospho p53 protein was detected by Western blot. Results After the treatment with ATRA, the apoptotic rates of Patu 8988 cells were increased compared with that in the control. TUNEL assay showed a strong positive reactions occurred after the treatment at 72hr. DNA degradation assay also showed a typical DNA ladder pattern consistent with apoptosis. Apoptosis of Patu 8988 cells was accompanied by the upregulation of bax and phospho p53 (Ser 46) expression, but the expression of bcl 2 is down regulated compared with that in the untreated cells. Conclusions ATRA is able to induce the apoptosis of pancreatic cancer cells, and the upregulated expression of bcl 2/bax and p53 is contributed to the apoptosis of the cells induced by ATRA.