Adipocyte-conditioned medium enhances the proliferation, motility and invasion of prostate cancer cell lines: Involvement of the microRNAs

Adipocytes (e.g., periprostatic adipose tissues, bone marrow) are one of the critical components in the prostate cancer tumor microenvironment. It has been reported that adipocytes influence the behavior of prostate cancer cells through adipocytokines and exosomes. We have previously shown effects of conditioned medium (CM) from adipocytes in behaviors of DU145 prostate cancer cells, and analyzed the microRNA profile of DU145 cells cultured in CM by a microarray. In this study, two additional cell lines (LNCaP and PC-3)were added to analyze cell behaviors. CM enhanced the proliferation, motility and invasion of PC-3 cells as same as DU-145 while not enhanced these behaviors of LNCaP, suggesting that CM promote androgen-independent cancer cell behaviors. However, in the invasion assay under CM, DU145 and PC-3 cells showed different amoeboid-mesenchymal transition plasticity, suggesting that effects of CM involve different mechanisms depending on the cell line. In addition, we re-analyzed the microRNA profiles of DU145 and PC-3 cells, verified target scores using miRDB and Target Scan, assessed overall survival and disease-free survival using GEPIA and Human Protein Atlas to identify candidate target genes. We also confirmed the expression levels of these candidate target genes in DU145 and PC3 cells using the DepMap. These results suggest that CM may affect behaviors of prostate cancer cells through microRNA-5787 and its multiple target genes such as WWOX and FLNA.