TNNC1 and cancer: Furthermore, the genes encoding cTnC (TNNC1; Id: COSG56773), fsTnC (TNNC2; Id: COSG65631), and all three TnT isoforms (TNNT1, Id: COSG65275; TNNT2, Id: COSG67007; TNNT3, Id: COSG60869) are overexpressed in several cancer types according to the COSMIC database.