TK6 SMAD/TGFbeta Reporter (Luc) cells are derived from the human lymphoblastoid TK6 cell line by stably integration of a SMAD/TGFbeta firefly luciferase reporter construct. TK6 cells are heterozygous for thymidine kinase (TK), are commonly used in research related to genotoxicity, mutagenesis, and DNA repair, as well as evaluating the safety of new drug candidates. TK6 SMAD/TGFbeta Reporter (Luc) cells stably express firefly luciferase under the control of the SMAD/TGFbeta response elements, can be used for monitoring the activity of TGF?/SMAD signaling pathway.