Effect of radiation on the viability of HepG2 cancer cell line targeted with different amount of radiosensitizer

Radiosensitizer (RS) were applied prior to radiation therapy to increase the therapeutic efficacy. This is due to some cancer cells were resistance toward radiation by producing large amount of antioxidant enzyme to scavenges the free radicals. The amount of RS added prior to irradiation played an important role to increase the efficacy of treatment but peroxide may cause unnecessary stress to the cancer cells before the treatment of irradiation. In this paper, different amount of RS were tested to evaluate the optimum amount of RS to avoid over-stress to the cancer cells while showing radiosensitizing effect by comparing to sample without RS. RS with different concentration started from 5% to 50% are added to hepatocellular carcinoma (HepG2) cancer cell line prior to 2Gy of fractionated dose. Cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, 24 hours after irradiation. In this study it is observed that the concentration of RS range between 5-20% did not cause reduction on the viability percentage of the studied HepG2 cells whereas 25-50% caused significant reduction on cell viability. The radiosensitizing effect of RS at 20% concentration exhibits 18.68% more cell death compared to treatment with radiation alone. It is therefore suggested that 20% is the optimum amount of RS which able to enhance the radiosensitizing ability without causing toxicity to the cell, thus induced more cancer cell death during radiotherapy