Analysis of human prostate cancer cell lines showed expression of S100A6 protein and mRNA in Du145 (derived from metastatic prostate in the brain), PC3 (derived from metastatic prostate in the bone), PC-3M and PC-3M-LN4 (metastatic variants of PC3), whereas the LNCaP cell line (derived from a lymph node metastasis) and LNCaP-LN3 and LNCaP-Pro5 cell lines (metastatic variants of LNCaP) (Pettaway et al, 1996) showed an absence of protein and mRNA. This evidence concerns the gene S100A6 and Familial prostate cancer.