CD44 and neoplasm: The binding of HA to CD44 triggers direct cross-signaling between different signaling pathways including HER2, c-src kinase and ERK [21,33,37,43,44,66] and it is this function which is thought to be involved in increased motility, adhesion, and invasion of cancer cells as well as tumor growth, including ovarian cancer [13,32,61,67,68].