GSE174471
Elucidating the mechanism underlying prostate turmorigenesis mediated by AR in Shh-responsive cells
The activation of the androgen receptor (AR) through binding of androgens is essential for prostate tumorigenesis. Although significant effort has been devoted to determining the intrinsic mechanism underlying AR action and designing therapies to directly target AR expressing tumor cells, these therapies failed in most prostate cancer patients. Here, we demonstrate that loss of AR in stromal sonic-hedgehog Gli1-lineage cells diminishes prostate epithelial oncogenesis and tumor development using both in vivo tissue recombination assays and mouse models. Single-cell RNA sequencing combined with other experimental analyses showed that AR loss in stromal Gli1-lineage niches resulted in robust increased expression of insulin-like growth factor binding protein 3 (IGFBP3) through attenuation of AR suppression on Sp1-regulated transcription. Aberrant increased IGFBP3 further inhibits IGF1 induced Wnt signaling activation in subsets of basal epithelial cells, impairing oncogenic cell growth and tumor development. IGFBP3 further showed to attenuate IGF1-induced oncogenic growth of prostatic organoids derived from mouse basal epithelia. Loss of human prostate tumor basal cell signatures was identified in basal cells with AR-deficient microenvironment. This study demonstrates the niche effect of stromal AR in Gli1-lineage cells in supporting prostate tumorigenesis, implicating co-targeting tumor epithelial and stromal AR signaling for treating advanced prostate cancer. Overall design: Two sequencing datasets were analyzed containing HiMyc and HiMyc-ARKO mouse prostate tissues