Although the mechanism of this alteration is not known, we can speculate that gal-9 slows down a feed-forward loop involving CD4+ Th1 + T-cells, interferon-γ, malignant cells and CXCL10 as explained in the cartoon on Fig. 7B. Our data showing that gal-9 produced by MB49 cells impairs the anti-tumor immune response probably by both cell-autonomous and cell-intrinsic mechanisms seems to contradict reports of a better prognosis for a category of human malignancies—especially breast carcinomas—with abundant expression of gal-918. This evidence concerns the gene CD4 and breast carcinoma.