Two independent preclinical advances aim to tackle the core challenge of applying cell therapy to solid tumors. Columbia University researchers reported in Science that HLA‑independent T (HIT) receptors—ultra‑sensitive CAR‑like constructs—cleared kidney, ovarian and pancreatic tumors in models by detecting vanishingly low antigen levels. The approach redefines antigen thresholds for targeting "stealth" tumor cells. Separately, researchers showed that deletion of the nuclear receptor NR2F6 in CAR‑T cells reverses exhaustion and potentiates antitumor immunity. Together, the studies provide complementary strategies—enhanced receptor sensitivity and removal of intracellular brakes—that could be combined to widen CAR‑T applicability beyond hematologic malignancies.