Hypoxia-induced autophagy promotes human prostate stromal cells survival and ER-stress.

Benign prostatic hyperplasia (BPH) is emerging as one of the most common diseases seriously threatening the health of elderly men. Accumulating evidences indicate that hypoxia could induce BPH. However, the underlying mechanism of BPH induced by hypoxia is not clear. In the study, hypoxia-induced autophagy could promote cell survival and endoplasmic reticula stress (ER stress) in WPMY-1 cells. Cell viability induced by hypoxia could been decreased by autophagy inhibitors (3-methyladenine, bafilomycin A1) or siRNA interference in two autophagy genes (Beclin1, ATG5) in WPMY-1 cells. Furthermore, ER stress was present in hypoxia-treated WPMY-1 cells, while autophagy and cell survival could been inhibited by C/EBP-homologous protein siRNA (CHOP), which is an important protein of ER stress pathway. Taken together, our data support a novel model that autophagy as a cytoprotective response promotes cell survival via ER stress under hypoxia in human prostate stromal cells.