Combinational Use of Phytochemicals and Chemotherapeutic Drugs Enhance Their Therapeutic Potential on Human Cervical Cancer Cells

The negative side effects of chemotherapeutic drugs have led to the need to identify safer therapeutics. A wide array of epidemiological and experimental data encourages the use of dietary agents to impede or delay different stages of cancer. Well tolerated lower doses of individual agents can be effectively employed if there is therapeutic synergy; thereby minimizing the side effects and enhancing successful outcome. However, a variety of interactions are possible when different agents are used in combination, therefore, dietary agents alone or in combination with chemotherapeutic agents must be thoroughly studied before considering them for clinical settings. This study was designed to determine the interaction of two phytochemicals (quercetin, sulforaphane) with each other as well as with established chemotherapeutic drugs, like cisplatin and 5-fluorouracil. Cell viability assay, cell cycle analysis, and scratch wound assay were performed to understand their combined impact on proliferation and metastasis of HeLa cells. Further, combination index (CI) was calculated to identify the type of interaction between the tested compounds concurrently. Concurrent administration of sublethal doses of the phytochemicals with chemotherapeutic drugs resulted in augmented anti-proliferative potential evidenced in elevated cytotoxicity, apoptosis induction, and inhibition of migration. Combination index was < 1 and indicated synergy between the tested compounds. Combination of these compounds can help to develop cancer treatment better.