Tenascin-C shapes TRAIL control over tumor immunity

TRAIL cytotoxicity is exploited as anti-cancer therapy since many years, however incomplete knowledge is generating many obstacles. Here, we address whether the highly abundant extracellular matrix molecule tenascin-C (TNC) orchestrating an immune suppressive tumor microenvironment and binding TRAIL impacts TRAIL cytotoxicity. We used an immune competent autologous NT193 breast cancer model with a knockdown (KD) of Tnfsf10 (encoding TRAIL) and observed accelerated tumor growth marked by less apoptosis, more proliferation and less myeloid cell infiltration as seen by flow cytometry. Grafting the same Tnfsf10 KD cells into a TNC knockout host showed repressed tumor growth suggesting that TNC is involved in regulating TRAIL functions.