CD44 and breast carcinoma: Notably, the PDE5 gene was inversely associated with multiple metastasis suppressor genes (MSGs) (ARHGDIB, BRMS1, CASP8, CD44, CDH2, MAP2K4, MAPK14, PEBP1) in three human breast cancer gene expression cohorts (GSE2034, GSE1456 and GSE26304).