Ohtani H, et al. - The in situ transforming growth factor β1 (TFGβ1) expression was evaluated during this study in subjects with lymphocyte-rich gastric carcinomas (Ly-rich GCs) with the aid of immunohistochemistry and in situ hybridization. The localization of latency-associated peptide (LAP) of TGFβ1 was primarily in immune cells in all cases, which was more abundant than in control GCs. The expression of LAP was more frequent in mature dendritic cells in Ly-rich GCs. Abundant expression of TGFβ1 in immune cells with contact to Treg cells in the lymphoid stroma. This, in turn, was consistent with the idea that TGFβ1 presented as one of the immunosuppressive factors in cancer stroma.