Mismatch repair deficiency in CRC induces a chemokine signature associated with CD8⁺ T cell recruitment. (A) Chemokine expression in dMMR CRCs and CIN CRCs from the TCGA PanCancer Atlas. (B) dMMR and CIN models of the MC38 mouse CRC cell line were created by mutating Mlh1 and Kras, respectively. Chemokine expression in the cell lines was assessed by qPCR. n = 3 repeats. (C and D) Chemokine secretion was analyzed by cytokine bead array of the cell supernatants (C) or Western blotting (D) of lysates from three different clones of dMMR MC38 cells and two different clones of CIN MC38 CRC cells. Clones 1 were used in all subsequent experiments. n = 3 repeats each. (E) Infiltration of CD8⁺CD3⁺ T cells into subcutaneously injected dMMR and CIN MC38 CRC tumors was assessed by flow cytometry. n ≥ 4 mice per group, four repeats. (F) Chemokine expression was assessed by qPCR on whole tissue transcripts isolated from subcutaneous dMMR and CIN CRCs. n ≥ 4 mice per group, four repeats. dMMR versus CIN: *, P ≤ 0.05; **, P ≤ 0.01; *** P, ≤ 0.005. RPKM, reads per kilobase million.