Protein expression analysis revealed that OBS increased Nrf2 (showing a 1.7- to 1.2-fold) and Bcl-2 levels (by 1.3- to 1.8-fold), and reduced Bax (by 0.7- to 0.8-fold) and caspase-3 (by 0.7- and 0.7-fold) levels altered by CIS treatment. Here, BCL2 is linked to in situ carcinoma.