Syk (spleen tyrosine kinase), a non-receptor tyrosine kinase that mediates signaling downstream of a variety of transmembrane receptors, has been detected to be highly associated with malignant tumors including, but not limited to, lymphoid malignancies, colon cancer, non-small cell lung cancer, breast cancer, and ovarian cancer 29, 37-39. Here, NTRK1 is linked to breast cancer.