Takanori Sano

Despite recent development of therapeutic strategies for intrahepatic lesions, standard guidelines for treatment of extrahepatic metastases of hepatocellular carcinoma have not been established. Surgical resection for intra-abdominal extrahepatic metastases of hepatocellular carcinoma was performed on 10 patients at our institution between 1992 and 2008. We retrospectively examined the clinicopathologic features and significance of a surgical approach in these patients. Nine of the 10 patients received treatment for primary hepatocellular carcinoma before surgery for intra-abdominal extrahepatic metastasis. A simultaneous intrahepatic lesion was detected in half of the patients when the extrahepatic metastasis was resected. Extrahepatic recurrent organs included adrenal glands, lymph nodes, abdominal wall, stomach and diaphragm. The mean survival period after resection was 36.1 months. Two patients are still alive without further recurrence. One patient died of retroperitoneal recurrence and 7 died of intrahepatic recurrence or liver failure after resection. With careful case selection, considering that not all extrahepatic metastases suggest systemic spread of hepatocellular carcinoma, surgical treatment for metastatic lesions in the abdominal cavity can provide a relatively good prognosis.

Background: Chemoresistance is a serious problem in pancreatic cancer, but the mechanism of resistance and strategies against the resistance have not been elucidated. We examined the potential of the phosphatidylinositol 3-kinase (PI3K)/Akt inhibitor LY294002 to enhance the anti-tumor effect of cisplatin and investigated the mechanism of chemoresistance in pancreatic cancer cells using a combination therapy of cisplatin and LY294002, both in vitro and in vivo. Methods: Cisplatin and LY294002, individually or in combination, were given to AsPC-1 and PANC-1 cell lines. Tumor growth, DNA fragments, and Akt phosphorylation were examined in vitro. To examine the therapeutic effect of cisplatin and LY294002, individually or combination an AsPC-1 tumor xenograft model was prepared for in vivo study. Results: Cisplatin induced growth inhibition and Akt phosphorylation in pancreatic cancer cells. LY294002 also inhibited cell proliferation but without showing Akt phosphorylation. However, the combination therapy markedly increased cleavage of caspase-3 and cytoplasmic histone-associated DNA fragments compared to the results with cisplatin alone. In the in vivo study, blocking the PI3K/Akt cascade with LY294002 increased the efficacy of cisplatin-induced inhibition of tumor growth in nude mice, suppressing half the tumor growth with cisplatin alone. There were no detectable side effects in mice treated with combination therapy. Conclusion: Our studies suggest that the PI3K/Akt pathway plays an important role in cisplatin resistance of pancreatic cancer cells. The augmentation of cisplatin with PI3K/Akt inhibitor may resolve the chemoresistance problem of cisplatin, and this might be a plausible strategy for achieving tolerance for chemotherapeutic agents in pancreatic cancer therapy.