In order to evaluate the capacity of human sarcoma cells to produce Kynurenine as an immunosuppressive mechanism, we exposed two sarcoma cell lines—namely IB115 (dedifferentiated liposarcoma) and IB136 (leiomyosarcoma)—to increasing concentrations of human interferon gamma (hIFNg) for 48 h before cell supernatant collection for Kynurenine measurement by mean of an immuno-assay (ImmuSmol). The gene discussed is IFNG; the disease is leiomyosarcoma.