CEACAM5 and colorectal cancer: Engineered with a colorectal cancer‐specific anti‐carcinoembryonic antigen (CEA) CAR, these FcγRI‐CAR‐HMs demonstrated potent tumoricidal activity (>80% CRC cell lysis in vitro), deep tissue penetration (>100 μm in 3D tumor spheroids), and significant therapeutic efficacy (≈89% tumor regression in vivo).