SH003 suppresses breast cancer growth by accumulating p62 in autolysosomes.

In this study, we demonstrate that SH003-induced autophagy via inhibiting STAT3 and mTOR results in an induction of lysosomal p62/SQSTM1 accumulation-mediated reactive oxygen species (ROS) generation and attenuates tumor growth. SH003 induced autophagosome and autolysosome formation by inhibiting activation of STAT3- and mTOR-mediated signaling pathways. However, SH003 blocked autophagy-mediated p62/SQSTM1 degradation through reducing of lysosomal proteases, Cathepsins, resulting in accumulation of p62/SQSTM1 in the lysosome. The accumulation of p62/SQSTM1 caused the increase of ROS, which resulted in the induction of apoptotic cell death. Therefore, we conclude that SH003 suppresses breast cancer growth by inducing autophagy. In addition, SH003-induced p62/SQSTM1 could function as an important mediator for ROS generation-dependent cell death suggesting that SH003 may be useful for treating breast cancer. PMID: 29179443 [PubMed]
Source: Oncotarget - Category: Cancer & Oncology Tags: Oncotarget Source Type: research