Shan Yan-Shen, Hsu Hui-Ping, Lai Ming-Derg, Yen Meng-Chi, Chen Wei-Ching, Fang Jung-Hua, Weng Tzu-Yang, Chen Yi-Ling
Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
1] Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan [2] Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Sci Rep. 2015 Apr 30;5:9783. doi: 10.1038/srep09783.
Gastric cancer metastasis remains a major cause of cancer-related deaths. There is an urgent need to develop new therapeutic approaches targeting metastatic gastric cancer. Argininosuccinate synthetase 1 (ASS1) expression is increased in gastric cancer. We detected the protein expression of ASS1 in human gastric cancer cell lines (AGS, NCI-N87, and MKN45) and in murine gastric cancer cell lines (3I and 3IB2). We used vector-mediated short hairpin RNA (shRNA) expression to silence ASS1 expression in the MKN45 and 3IB2 cell lines, and analyzed the effects of this protein on cell migration and metastasis. We demonstrated that ASS1 silencing suppressed cell migration in the MKN45 and 3IB2 cell lines. ASS1 knockdown significantly reduced liver metastasis in mice after the intrasplenic implantation of 3IB2 cancer cell clones. To determine whether arginine restriction may represent a therapeutic approach to treat gastric cancer, the sensitivity of tumor cells to arginine depletion was determined in gastric cancer cells. Arginine depletion significantly inhibited cell migration in the gastric cancer cell line. The silencing of ASS1 expression in MKN45 and 3IB2 gastric cancer cells markedly decreased STAT3 protein expression. In conclusion, our results indicate that the ASS1 protein is required for cell migration in gastric cancer cell lines.
胃癌转移仍然是癌症相关死亡的主要原因。迫切需要开发针对转移性胃癌的新治疗方法。精氨酸琥珀酸合成酶1（ASS1）在胃癌中的表达增加。我们检测了人胃癌细胞系（AGS、NCI-N87和MKN45）以及鼠胃癌细胞系（3I和3IB2）中ASS1的蛋白表达。我们使用载体介导的短发夹RNA（shRNA）表达来沉默MKN45和3IB2细胞系中的ASS1表达，并分析该蛋白对细胞迁移和转移的影响。我们证明，沉默ASS1可抑制MKN45和3IB2细胞系中的细胞迁移。在脾脏内植入3IB2癌细胞克隆后，敲低ASS1可显著减少小鼠的肝转移。为了确定精氨酸限制是否可能是治疗胃癌的一种方法，我们在胃癌细胞中测定了肿瘤细胞对精氨酸消耗的敏感性。精氨酸消耗显著抑制了胃癌细胞系中的细胞迁移。在MKN45和3IB2胃癌细胞中沉默ASS1表达显著降低了STAT3蛋白表达。总之，我们的结果表明，ASS1蛋白是胃癌细胞系中细胞迁移所必需的。
