Objective: To investigate the effect of docosahexaenoic acid (DHA) on apoptosis, migration and invasion of cervical cancer cell lines.
Methods: cervical cancer cell lines Hela and Siha in logarithmic phase were treated different concentrations of DHA. The morphological changes of the cells were observed microscopically and cell apoptosis was observed using Hoechst 33258 fluorescent staining. MTT assay was used to evaluate the effect of DHA in suppressing cell growth, and flow cytometry was employed to analyze the changes of cell apoptotic rate following DHA stimulations. Wound healing assay and Transwell migration assay were used to evaluate the migration of the cell lines. The expression levels of Bax, Bcl-2 cleaved caspase3, MMP-9 and VEGF proteins were detected by Western blotting.
Results: DHA exposure of the cells caused obvious morphological changes and dose-dependently increased the number of apoptotic bodies in the cells. MTT assay showed that DHA inhibited the growth of the cancer cells in a time- and concentration-dependent manner. DHA also effectively suppressed migration and invasion of the cancer cells. The cells exposed to DHA showed significantly down-regulation of Bcl-2, MMP-9 and VEGF proteins and up-regulation of cleaved-caspase 3 and Bax.
Conclusion: DHA can promote cervical carcinoma cell apoptosis by down-regulating the anti-apoptotic proteins Bax, Bcl-2 and cleaved-caspase3 and suppress cell invasion by decreasing MMP-9 and VEGF expressions.