Development of human prostate cancer cells to neuroendocrine-like cells by interleukin-1

Growth and development of some prostate epithelial cells are androgen-dependent. Non-androgenic hormones and growth factors may also influence prostate cells and the effect of interleukin 1beta (IL-1beta) has been investigated with an androgen-dependent human prostate cancer cell line LNCaP. Exposure of LNCaP cells to IL-1beta at picomole ranges resulted in a dose-dependent and progressive differentiation to neuroendocrine-like cells evidenced by dendrite formation and the development of specific neuroendocrine cell markers. Quantification by computer-based image analysis after immunostaining revealed a two-fold increase of chromogranin A in 90% of the cells and a ten-fold increase in the remaining 10%. Additionally, serotonin was developed in all the cells with the staining intensity increased by five-fold. Significant increase in cytokeratin 8 and reduction of prostate specific antigen was also noted. Proliferation was reduced in parallel to the cellular development. The IL-1beta effect was irreversible after several days of IL-1beta incubation. IL-1beta is produced constitutively and its secreted level has an inversed relation during the exponential and plateau phases of cell growth. An IL-1 autocrine regulation in the growth and differentiation of prostate cells is discussed.