Combination of 5-Florouracil and polyphenol EGCG exerts suppressive effects on oral cancer cells exposed to radiation

Abstract Objective Natural compounds such as epigallocatechin-3-gallate (EGCG) have previously shown chemotherapeutic properties with few side-effects. In our study, we evaluated the effects of combining EGCG with 5-fluorouracil (5-FU) and radiotherapy on oral squamous cell cancer. We evaluated whether the combination of lower doses of 5-FU with EGCG could be equally or more effective than the use of higher doses of 5-FU alone. Methods Cell viability, migration and cell cycles were assayed in oral cancer cell lines treated with 5-FU, 5-FU + EGCG and radiation (0, 2.5 and 5 Gy). Results This study found that the combination of EGCG with 5-FU reduced cell viability and migration distance compared to control samples and the same dose of 5-FU alone. Addition of EGCG increased the number of cells in the G2/M phase, while 5-FU arrested the cell cycle in phase S. Moreover, cell exposure to 5 Gy radiation decreased the effects of combining with EGCG. Conclusions In summary, the combination of EGCG and 5-FU reduced both cell viability and migration as well as altered the cell cycle to a greater extent than 5-FU alone.