To determine whether tumor resident TdTOSX+ cells can affect tumor growth as do CAFs, TdTOSX+ cells were sorted from primary B16-F10 tumors inoculated in 8 week old doxy-fed Osx-cre;TdT mice and re-injected along with B16-F10 tumor cells at 5:1 ratio into age-matched WT recipient animals (Figure 3A). This evidence concerns the gene SP7 and neoplasm.