Summary: | 碩士 === 國立中興大學 === 生物醫學研究所 === 104 === N-(carboxymethyl)lysine (CML), a prominent Advanced glycation end products (AGE) accumulate in human tissue proteins during aging, particularly under hyperglycemia conditions. CML induce oxidative stress, inflammation and association with cancer metastasis. However, the cellular and molecular mechanisms of the development, progression, and metastasis of gastric cancer still remain to be clarified. Because of bradykinin receptor B2 (BDKRB2) overexpression in gastric carcinoma, we studied its role in induction of peritoneal dissemination. Both CML and BDKRB2 is upregulated in gastric cancer tissues and associated with clinic-pathological stage. Gene silencing BDKRB2 gene inhibits peritoneal metastasis in animal model by PET/CT tomography and CML expression by ELISA. Unexpectedly, ligand binding assays demonstrated that CML binding with BDKRB2. Moreover, we found that CML-induced transcription factor aryl hydrocarbon receptor (AhR) expression and further regulate BDKRB2 axis. Subsequently, promote epithelial-mesenchymal transition (EMT) progression. These results proved via immune-fluoresce image, QPCR, Western Blotting, EMSA and CHIP assay. Importantly, gene silencing by AhR or pharmacology inhibitor alpha-Naphthoflavone (-NF) efficiently down regulated BDKRB2 and EMT by CML induction. These results are contrary to AhR overexpression and beta-Naphthoflavone (-NF), AhR pharmacology antagonist. Finally, gene silencing BDKRB2 or antagonist, HOE 140, also markedly decreased EMT characteristics of marker. Surprisingly, BDKRB2 also significantly displayed inflammation associated gastrointestinal cancer carcinogenesis by endoscope image and histology analysis via de-BDKRB2 and promoted AhR expression mechanism. We elucidate for the first time that AhR regulates BDKRB2 activation by CML, promotes gastric cancer EMT process and peritoneal dissemination. The mechanism not only in gastric cancer but also in colon cancer is same patent. These finding providing new insights to development of therapeutic approach to reduce tumor growth and peritoneal metastasis, may extend beyond cancer involving pathologic development.
|