In vivo and in vitro investigation of cytotoxic and antitumor activities of polyphenolic leaf extract of Hibiscus sabdariffa against breast cancer cell lines

In folk medicine Hibiscus sabdariffa (HS) L. (Malvaceae) has been used for the treatment of several ailments. HS leaf is highly enriched with polyphenol and many polyphenols is a very promising anticancer bioactive marker as inhibition of cell propagation and induction of differentiation. Therefore the main object of this research is to investigate the cytotoxic and anti-cancer activity of leaf extract of Hibiscus sabdariffa. Cytotoxic effect of polyphenol extract of Hibiscus sabdariffa leaves on breast cancer cell line (MCF-7, T– 47-D and MDA - MB-231) were investigated using SRB assay. Total phenolic and flavonoids contents were determined using HPTLC methods. In vitro, antioxidant activity was also determined. Antimetastasis, neovascularization potential of the extract was carried out in vivo study on the zebra fish model compared with standard drug paclitaxel. Extract of Hibiscus sabdariffa showed 50% growth inhibition of MCF-7, MDA-MB-231, and T-47-D cells in dose dependant manner, respectively as compared to standard drug adriamycin. HPTLC analysis revealed the presence of flavonoids and phenolic compounds and Significant (p<0.05) antioxidant activity was observed. Consistent with in vitro data, the polyphenol extract showed significant tumor growth inhibition (45 ± 2.24 %) in zebra fish equivalent to paclitaxel. The extract significantly reduced the angiogenesis (15 ± 0.7 %) (p<0.05) and inhibit the metastasis compared to the negative control group. The effective dose of 80 µg treatments reduced up to 60% of the tumor cells compared to the model. Similar reductions in neovascularization level and mortality levels were observed. Results reflected cytotoxicity in breast cancer cell lines and inhibits the growth of breast cancer cell lines (MDA-MB-231) and estrogen receptor-expressing breast cancer cell lines (MCF-7 and T-47-D), significant prevention of metastasis, and angiogenesis in zebra fish suggesting Hibiscus sabdariffa has the potential to be a good anti-cancer agent for breast cancer.