DPP4 and renal cell carcinoma: The first-in-human (FIH) phase I clinical study of YS110 for CD26-expressing solid tumors (23 MM, 9 RCC and 1 urothelial carcinoma (UTC)) was recently conducted [8], demonstrating that YS110 therapy exhibited a favorable safety profile and resulted in encouraging disease control in patients with advanced/refractory tumors.