The correlation of ECM-1 and Dkk-3 expression in WPMY-1 cells, ECM-1 inhibition of TGFBI-dependent prostate cancer cell invasion and the correlation of ECM1 and DKK3 expression with relapse-free survival, suggest that ECM-1 also participates in the Dkk-3 defense mechanism. This evidence concerns the gene DKK3 and Familial prostate cancer.