A Comparison of Thiazolyl blue (MTT) versus Sulforhodamine B (SRB) Assay in Assessment of Antiproliferative Effect of Bromelain on 4T1, AGS, and PC3 Cancer Cell Lines

All natural anticancer agents are cytotoxic basically and act mainly by the inhibition cell proliferation; but they have different mechanisms. Two assays, thiazolyl blue [3- (4, 5-dimethylthiazol-2-yl) -2, 5-diphenyl-terazoliumbromide or MTT] and sulforhodamine B (SRB), are used to assess cell growth. This study aimed to compare measurements between MTT and SRB on the cancer cell lines.
Different concentrations of the bromelain were added to cultured cells including mouse breast cancer (4T1), human gastric carcinoma (AGS), and human prostate carcinoma (PC3) cell lines and incubated at 24 and 48 hours. The growth and proliferation rates of the studied cells were investigated using both MTT and SRB assays after treatment with bromelain. The differences between cells were determined using Kruskal-Wallis and Dunns tests.
Findings: Bromelain significantly decreased growth and proliferation rate of 4T1, AGS and PC3 cancer cells, in a concentration-dependent manner at different times, in both MTT and SRB assays.
Findings showed that both MTT and SRB assays gained similar data regardless of the cell types.