NTRK1 and cancer: In addition to the EGFR family, an Eph receptor family of tyrosine receptor kinases (RTK) have critical functions in normal growth and development but were shown to be overexpressed in a host of human cancers (Zeng et al, 2003; Surawska et al, 2004; Fox et al, 2006; Taddei et al, 2009).