Objective: Mechanism of cell death inducing pathway of chloroform fraction of methanolic extract of Solanum nigrum were studied in a panel of cervical cancer cell line.Methods: Cells were treated with IC50 doses (previously determined by MTT assay), and various experiments were performed. For cellular and nuclear morphology, cells were stained with Hoechst33258 and observed under phase and fluorescence microscopy. Cell cycle shift and apoptotic assay (AnnexinV-FITC/PI) were studied by flow cytometry. Expressions of relevant genes were studied at the transcriptional and translational levels. ROS induction and loss of MMP and presence of γH2AX were studied by fluorescent microscopy. Constituents of the fraction were separated by column chromatography and bioassayed by MTT assay. Bioactive sub-fractions were identified by GC-MS.Results: Typical apoptotic morphological features were found in the treated cells. Most cells were found in late apoptotic stages. In HeLa and C33A cell lines, cells were blocked at G1/S, in SiHa, subG0 population increased. Expression of antiapoptotic Bcl-2 decreased and that of proapoptotic BAX, p53, p21 increased. Expression of HPV16 and human ET1 also decreased. ROS mediated DNA damage was detected and induced apoptosis. Different fatty acids along with other compounds were detected in the chloroform fraction, all of which are reported to have anticancer properties.
Conclusion:From the study it can be concluded that fatty acid rich chloroform fraction of S. nigrum is capable of inducing apoptosis in cervical cancer cells, through ROS mediated DNA damage.