Cografting CCL2-deficient fibroblasts with DCIS.com BC cells in the subrenal capsule model inhibited tumor invasion and survival associated with decreased expression of the proinvasive factor aldehyde dehydrogenase (ALDH1) and decreased expression of the proapoptotic factor Htra serine protease 2 (HTRA2). Here, CCL2 is linked to ductal breast carcinoma in situ.