AR and prostate cancer: To determine the importance of the CRD in sFRP1 for androgen-dependent prostate cancer cell proliferation, LNCaP cells and a subline of LNCaP, LNCaP-r, which expresses AR but is hormone resistant (Pousette et al, 1997), were transfected with empty vector, sFRP1 or the sFRP1 deletion mutants and grown in medium containing G418.