SQSTM1 and breast cancer: We previously showed that the endocrine therapy-resistant (estrogen-independent and Tamoxifen-resistant) MCF7-TamC3 cells exhibit lowered baseline autophagic flux levels [decreased expression of ATG12-ATG5 conjugate, increased expression of SQSTM1 (p62), and reduced rate of degradation of the SQSTM1 protein] compared to MCF7 breast cancer cells 15.