RESUMO
The present study has demonstrated that P-5m octapeptide (P-5m) has therapeutic potential in metastatic human hepatocarcinoma, possibly through the modulation of matrix metalloproteinase-2 expression. The purpose of the present study was to evaluate the antitumor effect of P-5m combined with 5-fluorouracil (5-Fu) on the treatment of hepatoma 22 (H22) hepatocarcinoma malignant ascites in a mouse model. The inhibitory effect on the growth of mouse ascites tumors was monitored by measuring body weight gain, survival time, ascites volume, numbers of tumor cells, DNA synthesis and peritoneal capillary permeability analysis. The present data revealed a significant reduction in ascites volume and cell count in mice that were treated with P-5m plus 5-Fu. Furthermore, the median survival time in mice in the combination group was prolonged compared with the disease control group. Moreover, a significant reduction in the total H22 ascites cell count in mice from the combination group was observed when compared with the disease control group. P-5m plus 5-Fu was able to induce the cell cycle arrest and inhibit the peritoneal capillary permeability of the mice. To conclude, the present study indicated that P-5m may have therapeutic potential in ascites caused by hepatocellular carcinoma.
RESUMO
P-5m, an octapeptide derived from domain 5 of HKa, was initially found to inhibit the invasion and migration of melanoma cells. The high metastatic potential of melanoma cells was prevented by the HGK motif in the P-5m peptide in vitro and in an experimental lung metastasis model, suggesting that P-5m may play an important role in the regulation of tumor metastasis. The aim of this study was to measure the effect of P-5m on tumor metastasis of human hepatocarcinoma cell line (HCCLM3) in vitro and in vivo in a nude mouse model of hepatocellular carcinoma (HCC), and detect the mechanisms involved in P-5m-induced anti-metastasis. By gelatin zymography, matrix metallo-proteinases 2 (MMP-2) activity in HCCLM3 was dramatically diminished by P-5m peptide. In addition, the migration and metastasis of HCCLM3 cells was also inhibited by the peptide in vitro. In an orthotopic model of HCC in nude mice, P-5m treatment effectively reduced the lung metastasis as well as the expression of MMP-2 in the tumor tissues. Overall, these observations indicate an important role for P-5m peptide in HCC invasion and metastasis, at least partially through modulation MMP-2 expression. These data suggests that P-5m may have therapeutic potential in metastatic human hepatocarcinoma.