NK cell immunotherapy against chemotherapy-resistant rhabdomyosarcoma

In children and young adults, rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma. Standard therapeutic concepts include surgery, chemotherapy and radiotherapy. Nevertheless, resistance can occur and the five-year survival rate of patients with metastatic or relapsed RMS is below 30% - underlining that new therapeutic approaches are urgently needed. Natural Killer (NK) cell immunotherapy has shown promise for the treatment of hematological diseases. Here, we investigated the interactions between NK cells and wildtype as well as chemotherapy-resistant RMS cell lines to learn more about RMS resistance and responsiveness to NK cells. We compared five parental RMS(RD, RH30, RH41, UKF-Rhb1 and RH36) to their vincristine-resistant sublines, as vincristine (VCR) is one of the standard cytostatic drugs used to treat RMS. To further improve NK cytotoxicity and allow specific retargeting, EGFR-CAR-NK cells were tested against the vincristine-resistant RMS cell lines. In addition, we plan to analyze chemotherapy-resistant Neuroblastoma cell lines, another common pediatric solid tumor.