胰腺癌致死率极高，但其恶性增殖及转移的机制仍不明确。我们前期研究发现胰腺癌组织高表达胰蛋白酶，而且高达13.5%的胰腺癌患者存在胰蛋白酶原基因（PRSS1）突变，提示突变型胰蛋白酶可能促进胰腺癌的恶性行为。因此，本课题拟开展以下研究：1）在细胞水平阐明提高突变型胰蛋白酶活性（过表达）对胰腺癌的促进作用，降低胰蛋白酶活性（RNAi）对胰腺癌恶性行为的抑制作用； 2）腹腔种植转染突变体的癌细胞，构建负瘤鼠模型，在体验证突变与胰腺癌增殖、转移的关系；3）确定胰腺癌增殖和转移是否和PRSS1突变造成的酶-抗酶失衡相关；4）过表达突变型胰蛋白酶，检测PAR-2和ERK是否激活，明确突变型胰蛋白酶通过PAR-2受体激活ERK信号通路促进肿瘤发展的机制。本课题将不仅在细胞、动物模型层次阐明胰腺癌恶性增殖和转移的新机制，而且可能发现胰腺癌治疗的新靶标。

Pancreatic cancer is a malignat tumor of digestive system with high mortality. But the mechanism of malignant proliferation and metastasis is not clear so far. Our previous studies have found that the expression of trypsin in pancreatic cancer tissues is high, and there are trypsinogen gene (PRSS1) mutation in patients with pancreatic cancer up to 13.5%. All of these prompt that mutant trypsin may promote the malignant behavior of pancreatic cancer cells. Therefore, this study would be conducted as follows:1) To clarify from forward and reverse aspects that the proliferation of pancreatic cancer cells would be promoted through over the expression mutant trypsin gene and the proliferation of pancreatic cancer cells would be inhibited through reducing the expression of mutant trypsin gene such as RNAi at the cellular level. 2) To plant the cancer cells which would have been transfected the gene of mutant trypsin to abdominal cavity of mouse and construct the model of mouse with pancreatic cancer in order to validate the relationship between the mutant trypsin and the proliferation and metastasis of pancreatic cancer cells in vivo. 3) To ensure whether the proliferation and metastasis of pancreatic cancer cells are related to enzyme - antienzyme imbalance which is caused by PRSS1 mutations. 4) To overexpress the mutant trypsin and detect whether PAR-2 and ERK are activated or not, so as to confirm the mutant trypsin via PAR-2 receptor activating ERK signal pathway to promote the proliferation and metastasis of pancreatic cancer cells. In summary, this research will probably not only elucidate the new molecular mechanism of the pancreatic cancer proliferation and metastasisfrom at cell and animal levels but also find new targets in the treatment.