Antioxidant activity in tumor sample was investigated by measuring the activity of malondialdehyde (MDA) and nitric oxide (NO). Tumors were weighed and mashed in ice-cold PBS solution before they were centrifuged at 8000 × g for 10 minutes in 4°C. For quantification of NO, the assay was carried out using Griess Reagent Kit for Nitrite Determination (Molecular Probes, Eugene, OR) in accordance to the user guidelines provided. For quantification of MDA, this assay was carried out according to the protocol outlined by Suhail et al.13 (link) Two hundred microliters of sample was mixed with 800 µL of PBS, 25 µL of butylated hydroxytoulene (BHT; 44 mg/5mL absolute ethanol solution), and 500 µL of 30% trichloroacetic acid before the mixture was subjected to vortex and incubated in ice for 2 hours. After 2 hours, it was centrifuged at 2000 × g for 15 minutes at room temperature. Then, 1 mL of supernatant obtained was mixed with 75 µL of 0.1 M EDTA and 250 µL of 1% thiobarbituric acid in 1 M NaOH and boiled for 15 minutes. After the solution cooled down to room temperature, the absorbance is recorded at 600 nm and 532 nm using a spectrophotometer (Beckman Coulter, Carlsbad, CA).