Chimeric antigen receptor (CAR) T cells have transformed hematologic cancer therapy but remain limited in solid tumors by antigen heterogeneity and a suppressive, pro-fibrotic microenvironment. We previously identified the urokinase plasminogen activator receptor (uPAR) as upregulated in senescent, pro-fibrotic cells and showed that uPAR-directed CAR T cells could safely reverse fibrosis in mice. Integrative analyses now reveal that uPAR is broadly expressed in solid tumors enriched for TP53 and RAS pathway mutations. These tumors adopt a progenitor-like state supported by a niche of uPAR-positive stromal cells with senescence features. Human uPAR CAR T cells eliminate tumor cells and their stromal support, induce durable regressions across diverse models, eradicate systemic metastases, and are potentiated by senescence-inducing therapies. Importantly, these cells achieve robust antitumor activity without sustained myelosuppression in mice reconstituted with human immune systems. Together, these findings establish uPAR as a broadly applicable CAR T target capable of overcoming major barriers in solid tumor therapy.
Zhang et al. (Sun,) studied this question.