We recently confirmed GLB1 as a marker of senescence in a well-described reference cell culture system and applied this to PCa tissue samples.[19] In that study of FFPE prostate tissues, GLB1 levels were markedly increased in HGPIN (p<0.0001), a pathologic entity known to contain senescent cells[32] and further found that primary PCa samples associated with metastatic disease had lower levels of expression compared to localized tumors (p = 0.0003). Here, GLB1 is linked to metastatic neoplasm.