TKT and lymphoma: The antigenotoxic effects of caffeinated and decaffeinated instant coffee, as well as boiled coffee (coarse ground roasted coffee was boiled in water and hot-filtered), against MNNG-induced genotoxicity was evaluated in mouse lymphoma L5178Y cells using multiple assays: the comet assay, Tk locus mutation assay, and cytokinesis-block micronucleus assay.