P08

Generation of CAR-T cells for the treatment of squamous cell carcinomas in Fanconi anemia patients

A López(1) P Vela(1) J Bueren(1) J A Casado(1)

1:CIEMAT/CIBERER

Fanconi anemia (FA) is an inherited disease associated with bone marrow failure and cancer predisposition. In particular, FA patients have a 600-fold increased incidence of head and neck squamous cell carcinoma (HNSCC). Current therapies for FA-HNSCCs are inefficient and toxic due to the hypersensitivity of FA patients to radio-chemotherapy. Thus, immunotherapy with CAR-T cells constitutes a promising therapeutic approach for these tumors. Since the generation of CAR-T cells requires a significant ex vivo manipulation of T cells, and given that FA cells are characterized by a significant fragility compared to healthy cells, we investigated the possibility of generating CAR-T cells from FA patients as an autologous cell therapy against HNSCCs. Peripheral blood T-lymphocytes from healthy donors (HD) and FA patients were transduced with a gamma-retroviral vector kindly provided by J. Maher, that expresses a second generation CAR against the EGF receptor (EGFR), highly expressed in HNSCCs. In addition, we generated a novel lentiviral vector harboring the EGFR-CAR and an inducible suicide gene, Cas9. Although the rate of expansion of retroviral-mediated FA CAR-T cells was lower as compared to HD CAR-T cells, in both instances strong cytotoxic effects against FA-HNSCC cells were observed. Preliminary results obtained in lentiviral-mediated CAR-T cells confirmed the efficient generation and cytotoxic activity of FA CAR-T cells. Moreover, in this case the induction of Cas9 resulted in the eradication of FA CAR-T from in vitro cultures. Our studies demonstrate the feasibility of generating CAR-T cells from FA patients for the autologous treatment of HNSCCs.