The data obtained from non‐reciprocal IFNα/βR−/− BM chimeras then indicated that liver radio‐resistant stromal cells represent a primary target of the anti‐tumor activity of IFNα, in keeping with the idea that the hepatic stroma can contribute to metastatic cancer cell proliferation (Braet et al, 2007; Vidal‐Vanaclocha, 2008; Sleeman et al, 2012; Spaapen et al, 2014). This evidence concerns the gene IFNA1 and metastatic malignant neoplasm.