Protein-bound polysaccharide K partially prevents apoptosis of circulating T cells induced by anti-cancer drug S-1 in patients with gastric cancer.
METHODS
It has been shown that T-cell dysfunction, including apoptosis of peripheral blood T cells, commonly occurs in patients receiving chemotherapy. In order to evaluate whether concomitant administration of the oral biological response modifier protein-bound polysaccharide K (PSK) could induce anti-apoptotic effects in patients treated with the anti-cancer drug, S-1, peripheral blood T cells were analyzed for induction of apoptosis, caspase-3 activities and expression of proapoptotic protein Bax and anti-apoptotic protein Bcl-2 in patients with curatively resected stage III gastric cancer, who were randomly assigned to postoperative adjuvant therapy with S-1 alone (n = 10) or S-1 combined with PSK (n = 10).


RESULTS
T-cell apoptosis 5 weeks after adjuvant therapy was significantly higher in the S-1 group (24.1 +/- 5.0%) than in the S-1 + PSK group (19.1 +/- 3.9%). S-1 induced T-cell apoptosis and concomitantly elevated caspase-3 activities and Bax expression in peripheral blood T cells. In addition, PSK partially prevented the T-cell apoptosis induced by S-1.


CONCLUSIONS
PSK could partially prevent the T-cell apoptosis induced by S-1.
Kono
Koji
K
First Department of Surgery, University of Yamanashi, Yamanashi, Japan. kojikono@yamanashi.ac.jp
Kawaguchi
Yoshihiko
Y
Mizukami
Yoshiki
Y
Mimura
Kousaku
K
Sugai
Hidemitsu
H
Akaike
Hidenori
H
Fujii
Hideki
H
D000368:Aged; D000903:Antibiotics, Antineoplastic / Q000627:therapeutic use*; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D017024:Chemotherapy, Adjuvant; D004338:Drug Combinations; D004359:Drug Therapy, Combination; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D010094:Oxonic Acid / Q000627:therapeutic use*; D011509:Proteoglycans / Q000627:therapeutic use*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D013274:Stomach Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D013601:T-Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D005641:Tegafur / Q000627:therapeutic use*; D051028:bcl-2-Associated X Protein / Q000378:metabolism
D000903:Antibiotics, Antineoplastic; D000964:Antimetabolites, Antineoplastic; D004338:Drug Combinations; D011509:Proteoglycans; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; C079198:S 1 (combination); D005641:Tegafur; C010770:polysaccharide-K; D010094:Oxonic Acid; D020169:Caspases