Characteristics of in vitro prostate cancer models grown in human serum

Abstract

Objective To compare growth, prostate serum antigen (PSA) production and integrin expression (α2β1, αvβ3, vitronectin receptor VR) in established in vitro models of prostate cancer, when growth media is supplemented with human serum (HS) from healthy men instead of fetal calf serum (FCS), the current standard supplement. Methods The cell lines RWPE, 22Rv1, and LNCaP representing increasing degrees of invasiveness, were cultured in growth media containing 1% HS or 10% FCS. Growth, PSA levels and integrin expression were measured using trypan blue exclusion, ELISA assays, monoclonal antibodies and flow cytometry respectively. Results There were no differences in growth or PSA production by cell lines cultured in HS versus FCS. Expression of the α2β1 integrin was observed to be significantly lower (p< 0.01) in 22Rv1s cultured in HS. 22Rv1 and LNCaP cell lines had lower α2β1 expression compared to RWPE (p<0.05). Expression of the αvβ3, VR was very minimal in all cell lines, although LNCaP expressed greater VR when cultured in HS compared to FCS (p = 0.03). Conclusions Cell lines representing human prostate cancer expressed differences in integrins reported to be involved in cell adhesion and angiogenesis when cultured using HS instead of FCS, despite the lack of change in growth and PSA production. This change in expression is significant in regard to standard culture methods and demonstrates that attempts to make culture methods more closely resemble human conditions must be considered. (Funding: CIHR grant; Elizabeth Donald Fellowship in Human Nutrition)