TPM3 and malignant colon neoplasm: KM12 represents a human colon cancer cell line expressing TrkA and more specifically tropomyosin 3-TrkA (TPM3-NTRK1) fusion protein [14, 53], since non-radiolabeled TRACK and entrectinib resulted in similar IC50 values in the nanomolar range when competing with [18F]TRACK binding in KM12 cells.