NEUROTENSIN IS METABOLIZED BY ENDOGENOUS PROTEASES IN PROSTATE-CANCERCELL-LINES

The formation and processing of neurotensin (NT) by three prostate can cer cell lines was investigated. Neurotensin (NT) immunoreactivity was detected in conditioned media and extracts of LNCaP cells. Using HPLC techniques, the immunoreactivity extracted from LNCaP cells coeluted with synthetic NT standard. Metalloendopeptidase 3.4.24.15 activity wa s detected in PC-3, DU-145 and LNCaP cells, whereas high levels of neu tral endopeptidase 3.4.24.11 activity was detected only in LNCaP cells . NT was relatively stable when incubated with PC-3 or D-145 cells but was rapidly degraded by LNCaP cells to NT1-11 and NT1-10. Phosphorami don inhibited the metabolism of NT by LNCaP cells. These data suggest that NT is present in and metabolized by LNCaP cellular enzymes. (C) 1 998 Elsevier Science Inc.