CD44 and melanoma: The inhibition of CD44 using anti-CD44 antibodies as anti-melanoma treatment showed success in an experimental study [41], while a recent phase I clinical trial of an anti-CD44 humanized antibody using the RG7356 in patients with metastatic or locally advanced CD44-expressing solid malignancies (6 melanoma from 65 different solid tumors of various entities) only demonstrated a modest anti-tumor activity [42] demanding alternative strategies to overcome CD44 expression in tumors.