In our orthotopic PDAC mouse model, RabMab1 lowers the levels of stromal CD206+ TAMs and impedes systemic spread; we propose that amelioration of metastases may in part be due to a decrease in TAMs because M2 polarized TAMs are known to promote epithelial-mesenchymal transition of pancreatic cancer cells [28]. Here, MRC1 is linked to familial pancreatic carcinoma.