CHAC1 and breast cancer: Identifying novel biomarkers responsible for tumor progression may provide a better course of treatment, and may also contribute in improving the prognosis of breast cancer patients (5, 6) Located on chromosome no 2 (2p16.2), Cation transport regulator homolog 2 (CHAC2) is one of the members of the CHAC family that catalyzes the glutathione degradation to 5-oxoproline and cystein-glycine, however with lower catalytic efficiency compared to CHAC1 (7).