The effect of polysaccharide k with S-1 based chemotherapy in advanced gastric cancer.

Background/aims: Polysaccharide K (PSK) is widely used in Japan as a biological response modifier for cancer patients. We investigated the effects of PSK with S-1 based chemotherapy for advanced gastric cancer patients in immune response.

Methodology: Nine advanced gastric cancer patients who underwent chemotherapy at the University of Tokushima were included in this study. In all patients, 3g PSK was received orally and S-1 based chemotherapy for 2 weeks alternately for 8 weeks. Serial changes in immunological parameters (Foxp3, Natural killer (NK), CD4/CD8) were monitored.

Results: The levels of Foxp3 at 8 weeks was significantly decreased compared with 2 weeks (4.26% vs. 3.11%). In NK activity at 8 weeks was significantly increased compared with 2 weeks (27% vs. 47%).

Conclusions: These results of this study suggested that chemotherapy with PSK improved the immune response in advanced gastric cancer patients. Especially Foxp3 was concerned in this mechanism.