DETECTION OF PSP94 AND ITS SPECIFIC BINDING-SITES IN THE PROSTATE ADENOCARCINOMA CELL-LINE LNCAP

Purpose: To evaluate the expression of prostate secretory protein of 9 4 amino acids (PSP94) and PSP94 binding proteins in the LNCaP cell lin e. Materials and Methods: The reverse-transcription polymerase chain r eaction (RT-PCR) and Southern blot hybridization were employed to assa y the expression of PSP94. Immunoprecipitation with specific polyclona l antibodies was used to detect PSP94 secreted by the LNCaP cells. The binding proteins were assayed by equilibrium binding assays. Results: PSP94 was expressed and secreted in the LNCaP cells. As well as, LNCa P cells expressed surface membrane proteins capable of binding PSP94 i n a specific and saturable manner. Exposure of LNCaP cells to exogenou s PSP94 resulted in the up-regulation of PSP94 binding sites, indicati ng functional interactions for PSP94 and its receptor in this cell lin e. Conclusion: The expression of PSP94 and its receptors may bet parti ally regulated by an autocrine pathway in the LNCaP cell line.