Abstract :
Introduction: Prostate cancer is a potentially fatal condition considered as the most common non-skin cancer in the United State. In the Philippines, it is one of the top five cancers among men and 19.3 out of 100,000 male populations have prostate cancer. Different treatments have been used in prostate cancer such as chemotherapy, biotherapy and radiation therapy. Though these treatments are effective, they are very expensive. Researchers are constantly seeking new and more practical treatments which are not only effective but also cheap. Philippines is rich in natural resources as evidenced by its variety of plant species that have been reported to have medicinal values such as Molave (V. parviflora). Molave contains natural polyphenolic compounds (flavonoids) reported to have cytotoxic activity against cancer cells. The current study investigated the effect of crude flavonoid extract from Molave against PC-3 cell line. Specifically, it aimed to determine the concentration and time of exposure yielding the highest cytotoxic activity. Material and Methods: Flavonoid extract from Molave was as an intervention. MTT colorimetric assay was employed to assess the cytotoxic activity of Molave. Eight concentrations of the extract (500, 250, 125, 62.5, 31.25, 15.63, 7.81, 3.91 [micro]g/mL of plant extracts and 200 [micro]g/mL Doxorubicin HCl dissolved in 1% DMSO) were tested on PC-3 cells. The cells were incubated for 24 hours at 37[degrees]C, 5% CO2, 95% air and 100% relative humidity. After treatment, the absorbance was measured at 595 nm using Opsys MR[TM] 96-well microplate reader. Result: The data gathered from MTT assay show that the extract was able to elicit cytotoxic effect against PC-3 cells. Statistical analysis showed a significant difference between the untreated cells and extract concentrations of 250 and 500 [micro]g/mL for 24hr incubation, indicating their effectiveness in lowering the number of cancer cells. Also, 48-hr incubation was done and statistical analysis of the data also showed significant difference between the untreated cells and extract concentrations of 125, 250 and 500 [micro]g/mL; suggesting that prolonging incubation period can have better effect in lowering cancer cells. Conclusion: Data generated from the study suggests that flavonoid extract from V. parviflora leaves had cytotoxic activity against the PC-3 cell line. Keywords: flavonoids, PC-3 cell line, MTT cytotoxicity assay