NTRK1 and neoplasm: Decorin acts as a powerful tumor suppressor by inducing the p21WAF1/CIP1 cyclin-dependent kinase inhibitor [26], as well as through its ability to directly bind and block the action of several receptor tyrosine kinases (RTKs) such as EGFR [27,28], the hepatocyte growth factor receptor Met [29], vascular endothelial growth factor receptor (VEGFR) [30], and insulin-like growth factor-1 receptor (IGF-1R) [31].