A preliminary study of single intraperitoneal administration of paclitaxel followed by sequential systemic chemotherapy with S-1 plus paclitaxel for advanced gastric cancer with peritoneal metastasis.

AIM: A preliminary study with the aim of evaluating the safety and efficacy of a single intraperitoneal administration of paclitaxel, combined with intravenous administration of paclitaxel plus S-1, was carried out in gastric cancer patients with peritoneal metastasis. PATIENTS AND METHODS: Paclitaxel was administered intraperitoneally at 80 mg/m(2). After one to two weeks, S-1 was administered at 80 mg/m(2)/day for 14 consecutive days, followed by seven days' rest. Paclitaxel was administered intravenously at 50 mg/m(2) on days 1 and 8. The safety, pharmacokinetic analysis and efficacy of this therapy were investigated. RESULTS: Fifteen patients were enrolled in this study. The toxic effects of the intraperitoneal chemotherapy were mild. The toxic effects with the systemic chemotherapy were acceptable. The ratio of (AUC peri)/(AUC pla) was 1065:1 in the pharmacokinetic analysis. The one-year overall survival rate was 10/15 (66.7%). CONCLUSION: A single intraperitoneal administration of paclitaxel combined with intravenous administration of paclitaxel plus S-1 is a well-tolerated and feasible treatment for patients with gastric cancer with peritoneal metastasis.

NS-398 inhibits tumor growth and liver metastasis of colon cancer through induction of apoptosis and suppression of the plasminogen activation system in a mouse model.

BACKGROUND: Cyclooxygenase-2 (COX-2) is overexpressed in colon cancers. The plasminogen activation (PA) system relates to cancer invasion and metastasis through the degradation of the extracellular matrix. COX-2 also relates to degradation of the extracellular matrix, but the relationship between COX-2 and the plasminogen activator system is unclear. STUDY DESIGN: In vivo: Colon 38 (G0) primary and (G5) metastatic cell lines were implanted in C57BL/6 mice treated with or without COX-2 inhibitor (NS-398). Animal survival and tumor growth were measured. On day 19, tumors were excised and tumor cell apoptosis measured. For metastasis, G5 cells were injected into the spleen, and, after 23 days, liver metastasis was determined. In vitro: G0 or G5 cells were treated with NS-398. Supernatant prostaglandin E2 and mRNA expressions of COX-2, vascular endothelial growth factor (VEGF), urokinase-type plasminogen activator (u-PA), u-PA receptor, plasminogen activator inhibitor type-1 (PAI-1), and PAI-2 were measured. Tumor cell proliferation was also determined. RESULTS: In vivo: Mean survival of NS-398-treated animals was higher than controls for both G5 and G0 (G5: p < 0.003, G0: p < 0.02). G5 tumors grew faster than G0 tumors (p < 0.001) and NS-398 significantly inhibited tumor growth (p < 0.001), induced tumor cell apoptosis (p < 0.001), and significantly reduced metastasis (p < 0.003) in G5 animals. In vitro: PGE(2) production was higher in G5 than G0 cells (p < 0.001); NS-398 significantly reduced prostaglandin E(2) levels in G5 cells (p < 0.001). mRNA expression of COX-2, vascular endothelial growth factor, and u-PA receptor was higher in G5 than G0 cells, and NS-398 significantly inhibited u-PA mRNA expression in G5 cells. NS-398 significantly reduced proliferation in G5 cells (p < 0.05). CONCLUSIONS: COX-2 inhibition significantly decreases tumor growth in this model by inducing apoptosis and blocking u-PA production in G5 colon cancer cells, which is associated with significant inhibition of liver metastases.