TNN and neoplasm: The observation that tenascin-W co-localizes with endothelial cell markers in the tumor stroma of brain (Martina et al., 2010), kidney, colon, breast, ovary, and prostate cancer (Brellier et al., 2012b), but is completely absent in corresponding normal tissues, encouraged additional studies to determine a possible function of tenascin-W in promoting tumor angiogenesis.