CAR T-cell therapy has been highly effective in hematologic cancers but faces challenges in solid tumors due to the lack of safe, uniformly expressed surface antigens. A recent study found that the MiT/TFE-family fusion-driven glycoprotein NMB (GPNMB) is highly, homogeneously and stably expressed in primary and relapsed alveolar soft-part sarcoma (ASPS) and translocation renal cell carcinoma (tRCC).