Sarcosine induces increase in HER2/neu expression in androgen-dependent prostate cancer cells

Increasing evidence suggests that Human epidermal growth factor receptor 2 (HER2/neu) is involved in progression of prostate cancer. Recently, sarcosine was reported to be highly increased during prostate cancer progression, and exogenous sarcosine induces an invasive phenotype in benign prostate epithelial cells. The aim of this work was to investigate the effect of sarcosine on HER2/neu expression in prostate cancer cell lines LNCaP (androgen dependent), PC-3 and DU145 (both androgen independent). Relative amounts of HER2/neu and androgen receptor (AR) transcripts were determined using RT-qPCR. Total expression of HER2/neu was confirmed by Western blot (WB). HER2/neu protein on the surface of living LNCaP cells was visualized by confocal microscopy using a HER2/neu-specific fluorescent probe. Exposure of LNCaP cells to 50 μM sarcosine for 24 h resulted in a 58% increase of the HER2/neu mRNA level ( P