GSS and malignant colon neoplasm: Ki et al. demonstrated that the mRNA and protein expression of GSH, the catalytic subunit of GCL (GCLC) and GSS, were significantly increased in the following five colon cancer cell lines: Caco 2, SNU 407, SNU 1033, HCT 116, and HT 29, when compared to the normal colon cell line FHC.