Comparison of potential chemotherapeutic agents, 5-fluoruracil, green tea, and thymoquinone on colon cancer cells.

Antioxidants have been found to be quite successful in deterring certain disease processes for years, especially cancer. Antioxidants protect the body by neutralizing the free radicals and donating one of their own electrons, thus ending the scavenger reaction. Epigallocatechin-3-gallate (EGCG), the most abundant catechin found in green tea, is a valuable scavenger of reactive oxygen species in vitro as well as in vivo. Thymoquinone (TQ), a major active component of black seed (Nigella sativa), is also known for its powerful scavenger abilities as an inhibitor of oxidative stress and has been utilized in the Middle East for centuries for healing properties. These two potent antioxidants when compared to the chemotherapeutic drug of choice, 5-fluorouracil (5-FU), have demonstrated incredible chemotherapeutic responses to the SW-626 cell line. The objective of this study was to evaluate and compare the effects of SW-626 colon cancer cells after a 24, 48, and 72 hour incubation periods with low, medium, and high doses of EGCG, TQ, and 5-FU. Cell viability, cell number, cellular morphology, and cellular metabolism were compared for the control and treatment groups. The results of this study evidenced a similar significant decrease in cell number as early as 24 hours in the groups treated with TQ and EGCG compared to 5-FU. Increases in cellular damage were evident after 24, 48, and 72 hours and in all treated groups compared with the control. Reduced cell numbers in the treated groups suggests the possibility that TQ and EGCG may have similar chemotherapeutic effects on cancer cells as 5-FU.