This supports the hypothesis of a specific protective role of high infiltration of breast tumors by cDC1, rather than the alternate hypothesis that differential levels of cDC1 gene expression in tumors reflect differences in their overall leukocyte infiltration and lead recapitulates the known different clinical outcome of “Hot” or “Warm” vs. “Cold” or “Icy” tumors. Here, MPPE1 is linked to breast neoplasm.