CD44 and prostate cancer: In cultured supernatants from prostate cancer cell lines derived from bone metastasis (PC3), soluble CD44, and variant 6 isoform (v6) was identified, however, it was not identified in lymph node metastatic prostate cancer cell line (LNCaP, Stevens et al., 1996; Desai et al., 2009; Gupta et al., 2012).