SPARC and posterior cortical atrophy: Of the genes found to be present at reduced levels in the Ago complex (Table 1), the Thy-1 cell surface antigen (THY1) [24], chemokine (C-C motif ligand 2 (CCL2, MCP1)) [45], matrix Gla protein (MGP) [46], periostin (POSTN) [47, 48], secreted protein, acidic, cysteine-rich (SPARC, osteonectin) [49], or cathepsin K (CSTK) [50] have been found to be overexpressed in PCa.