Fig. 7. MSCs in tumor stroma serve as an ALDHhigh cancer stem cell niche.
(A) Immunofluorescence analyses were performed on tumors derived from LoVo cells (5 × 104 cells/injection) injected along with tdTomato-MSCs (5 × 105 cells/injection), using antibodies against tdTomato-RFP (in green), ALDH1 (in red, panel a), Fibroblast Surface Protein FSP (in red, panel b), and COX2 (cyan). Panels a and b are serial sections from one tumor. (B) IL-1 and COX2 mRNA expression in human colon and breast carcinoma. The “Fold Change” indicates the average mRNA levels of the three genes in colon mucinous carcinoma samples, compared to that of normal colon samples (panel a) and in TNBC samples, compared to that of non-TNBC samples (panel b). (C) The proposed interactions for induction and maintenance of EMT, cancer cell stemness and invasiveness by MSCs. AA: arachidonic acid