Gal-9 is localized in the cytoplasm and on the cell surface of cells and seems to be released from cancer cells. In solid tumors, the available studies suggested that Gal-9 has a cancer-suppressor function, with loss of Gal-9 being closely associated with increased metastasis and high recurrence. Kadowaki et al also showed that Gal-9 signaling can prolong survival by inducing macrophages to differentiate into plasmacytoid dendritic cell-like macrophages in a mouse lung-cancer model. These datas presented that Gal-9 may be a possible prognostic factor with anti-metastatic potential.
Jiang J, Jin M-S, Kong F, et al. Decreased Galectin-9 and Increased Tim-3 Expression Are Related to Poor Prognosis in Gastric Cancer. Busson P, ed. PLoS ONE. 2013;8(12):e81799.