Ms. Stratton et al., Expression of the matrix metalloproteinase promatrilysin in coculture of prostate carcinoma cell lines, PROSTATE, 48(3), 2001, pp. 206-209
BACKGROUND. Matrix metalloproteinases (MMPs) are involved in tumor progress
ion. Matrilysin (MMP-7) has been shown to be upregulated in prostatic carci
nomas and can increase the invasive capacity of DU-145 cells. Because of th
e heterogenous nature of prostatic tumors, we examined promatrilysin expres
sion in cocultures containing two different prostatic carcinoma cell lines,
DU-145 and LNCaP.
METHODS. Using enzyme linked immunosorbent assay (ELISA) analyses, promatri
lysin expression was measured in DU-145/LNCaP cocultures and conditioned me
dia cross-cultures. The effects of blocking IL-6 on promatrilysin expressio
n were examined by pretreating conditioned media with IL-6 neutralizing ant
ibody.
RESULTS. A significant induction of promatrilysin expression was observed i
n DU-145/LNCaP cocultures compared to LNCaP cells alone. In addition, DU-14
5 conditioned medium induced the same fold induction of promatrilysin as wa
s observed in the cocultures. LNCaP cell conditioned medium did not induce
promatrilysin expression in DU-145 cells. Neutralization of IL-6 with neutr
alizing antibody abrogated DU-145 conditioned media induced promatrilysin e
xpression to baseline levels.
CONCLUSIONS. IL-6 secreted by DU-145 cells can induce promatrilysin express
ion in LNCaP cells. IL-6, in vivo, may act as a paracrine signaling factor
that regulates matrix metalloproteinase expression. Therefore, IL-6 may pla
y a role in invasive metastatic processes of a prostate carcinoma.