An objective of the present invention is to provide novel therapeutic agents for cancer, which have an excellent antitumor effect in cancer patients by enhancing their immune function. The present inventors discovered that the administration of at IL-6 inhibitor and/or gemcitabine or a salt thereof to tumor-bearing organisms yields an excellent antitumor T cell response-enhancing effect, and completed the present invention. In addition, the present inventors discovered that the T cell response-enhancing effect produces an excellent antitumor effect.
