FPOA induces apoptosis in HeLa human cervical cancer cells through a caspase-mediated pathway

In the present study, the triterpenoid 3-acetoxylanosta-8,24-dien-21-oic acid (FPOA) was extracted from Fomitopsis pinicola. The aim of the present was to elucidate the mechanism of action of FPOA in HeLa cervical cancer cells. Cell viability was examined using an MTT assay and the morphological detection of apoptosis was conducted using DAPI staining. The rate of apoptosis was examined via Annexin V-FITC/PI double staining and the expression levels of apoptosis-associated proteins were determined by western blot analysis. FPOA was observed to inhibit HeLa cell proliferation, with IC(50) values of 25.28, 15.30 and 11.79 µg/ml at 24, 48 and 72 h, respectively. Typical apoptotic bodies were observed in the HeLa cells following treatment with FPOA, as revealed by DAPI staining. The percentage of apoptotic cells was 3.00, 3.12, 6.18 and 32.28% following treatment with FPOA at concentrations of 0, 7.5, 15 and 30 µg/ml, respectively. Western blot analysis showed that caspase-3 and −9 were cleaved more frequently after treatment with FPOA. Furthermore, the expression of Bax was increased but Bcl-2 expression was decreased after treatment with FPOA. These results suggest that FPOA can induce HeLa cell apoptosis through a caspase-mediated pathway.