Anti-proliferative Activity of Hibiscus sabdariffa L. Calyx Flavonoid Extracts on Cervical Cancer Cells using Flow Cytometry

Background: Impairment of the normal progression of the cell cycle affects the growth and development of the daughter cells, which may result in cancer cell proliferation. Herein, we investigate the effect of flavonoid fractions of Hibiscus sabdariffa L. calyx on cell cycle progression in cervical cancer cells. Methods: Flavonoids (bound and free), lipids and aqueous fractions were extracted from a methanolic extract of H. sabdariffa calyx using ethyl acetate, diethyl ether and petroleum ether. Each of these fractions were used to treat HeLa cervical cancer cells and monitored using a flow cytometer. Results: The cells exposed to the extract and its fractions had higher percentages of inactive cells (no cell division) at the quiescent (G0) and gap one phases (G1) of the cell cycle in comparison to control cells. The highest values were obtained from cells treated with the bound and free flavonoid fractions. Conclusion: The results of this study suggest that HeLa cervical cancer cell proliferation is significantly inhibited by H. sabdariffa flavonoid fractions. Daily consumption of beverages consisting of H. sabdariffa may therefore prevent the early stages of cervical cancer and inhibit the progression of the disease once it is established.