Furthermore, considering that 5a can block the active site of αvβ6/αvβ8 and inhibit TGFβ activation (a potent immunosuppressive mechanism in tumors), our results suggest that this peptide is a peculiar tumor-homing bi-selective inhibitor of αvβ6 and αvβ8 that could be exploited for targeting this immunosuppressive mechanism in tumors. The gene discussed is TGFB1; the disease is neoplasm.