Objective: To determine the screening of the expression of membrane proteins in androgen-dependent prostate cancer (ADPC) and androgen-independent prostate cancer (AIPC) and to explore the mechanism of membrane proteins in these two cancers.
Methods: Serum samples were collected from 3 patients with ADPC and another 3 patients with AIPC. The serum was incubated with ADPC cell line LNCaP and/or AIPC cell line PC-3 and detected by immunoprecipitation and Western blot. Differentially expressed proteins between ADPC and AIPC identified by mass spectrometry were compared and their expression level and location were analyzed by immunofluorescence.
Results: Altogether 11 membrane proteins were identifited, such as the Neural-Cadherin precursor, ER60 precursor, Claudin-4, and so on. Immunofluorescence revealed that the expression level of Claudin-4 in PC-3 cells was higher than in LNCaP cells.
Conclusion: We can use the screening method to study membrane proteins in prostate cancer. Claudin-4 may play an important role in the pathogenesis and the development of AIPC.