Figure 1

Androgen depletion and high cell density both promote neuroendocrine transdifferentiation (NED) of LNCaP and LAPC-4 cells independent of AR activity. LNCaP and LAPC-4 cells were cultivated for 2 to 16 days in the presence (FBS) or absence (CS) of androgens in the cultivation medium. A, Western blot analysis of the expression of γ-enolase and tubulin β-III. B, qRT-PCR analysis of changes in mRNA levels of L-dopa decarboxylase (DDC), chromogranin A (CHGA), and γ-enolase (ENO2). The bars represent means ± standard deviation (SD) from three independent experiments. C, Immunofluorescence detection of tubulin β-III expression in LNCaP cells. D, Western blot analysis of changes in expression of androgen receptor (AR) in LNCaP and LAPC-4 cells. AR activity was assessed by (E) western blot analysis of protein levels of androgens-regulated protein tumor necrosis factor receptor superfamily member 10D (DcR2), and (F) qRT-PCR analysis of changes in mRNA levels of the prostate-specific antigen (KLK3). The data represent means ± SD of three independent experiments. “*”denotes statistical significance (P < 0.05) compared with control (2 days in FBS).