NTRK1 and osteosarcoma: β−adrenergic signaling promotes pro−angiogenic and stress−response programs in sarcomas; propranolol reduced proliferation and angiogenesis and enhanced cisplatin efficacy in osteosarcoma xenografts, nominating β−blockade as a feasible adjunct to TRK inhibition and to immune checkpoint therapy where adrenergic tone blunts effector function (79, 80).