One of these genes is BGN, a signaling molecule derived from the ECM, which is involved in collagen fiber assembly, tumor invasion, and metastasis.[50] Previous studies by Frank et al[51] have demonstrated a positive correlation of BGN protein expression with prostate-specific antigen recurrence, TMPRRS2:ERG fusion, and PTEN deletion in PCa. The gene discussed is PTEN; the disease is posterior cortical atrophy.