Jung Ki Yoo1, Ji Min Lee1, Seung Hee Kang1, Seong Ho Jeon1, Chang Min Kim1, Seung-Hun Oh2, Chang-Hyun Kim3, Nam Keun Kim4, Jin Kyeoung Kim5. 1. Department of Pharmacy, College of Pharmacy, CHA University, 335 Pangyo-ro, Bundang-gu, Seongman-si, Gyeonggi-do, 463-400, Republic of Korea. 2. Department of Neurology, CHA Bundang Medical Center, CHA University, Seongnam-si, Gyeonggi-do, 463-954, Republic of Korea. 3. College of Medicine, Dongguk Ilsan Hospital, Gyeonggi-do, 410-773, Republic of Korea. 4. Department of Biomedical Science, College of Life Science, CHA University, 335 Pangyo-ro, Bundang-gu, Seongman-si, Gyeonggi-do, 463-400, Republic of Korea. 5. Department of Pharmacy, College of Pharmacy, CHA University, 335 Pangyo-ro, Bundang-gu, Seongman-si, Gyeonggi-do, 463-400, Republic of Korea. Electronic address: kyeoung66@hanmail.net.
Abstract
OBJECTIVES: MicroRNAs have critical roles in cancer development by regulating the expression of oncogenes or tumor suppressor genes. We identified and characterized a novel miRNA, miR-CHA1, in human lung cancer cells. The aim of this study was to investigate its novel function in human lung cancer by targeting XIAP. MATERIAL AND METHODS: Novel miRNA cloning, Real-time qRT-PCR, western blotting, dual luciferase assay, miRNA transfection, proliferation and apoptosis assay were carried on human lung cancer cell line A549. Fifteen paired NSCLC tissues and noncancerous lung tissues were collected. In vivo xenograft assay was performed. RESULTS: Expression of miR-CHA1 was downregulated in human lung cancer cell lines and tissues compared with normal cells and tissues. We identified a putative target gene, XIAP, whose expression was regulated by miR-CHA1 overexpression. XIAP is an inhibitor of apoptosis that represses the activation of caspase 3 and 9. XIAP mRNA and protein levels were directly suppressed by miR-CHA1. XIAP has an important role in carcinogenesis, and previous studies suggest that it may regulate cell survival and proliferation by its anti-apoptotic ability. CONCLUSION: Taken together, miR-CHA1 inhibited cell proliferation and induced apoptosis in vitro and in vivo by targeting XIAP. These data can be applied to identify novel therapeutic targets for lung cancer therapy.
OBJECTIVES: MicroRNAs have critical roles in cancer development by regulating the expression of oncogenes or tumor suppressor genes. We identified and characterized a novel miRNA, miR-CHA1, in humanlung cancer cells. The aim of this study was to investigate its novel function in humanlung cancer by targeting XIAP. MATERIAL AND METHODS: Novel miRNA cloning, Real-time qRT-PCR, western blotting, dual luciferase assay, miRNA transfection, proliferation and apoptosis assay were carried on humanlung cancer cell line A549. Fifteen paired NSCLC tissues and noncancerous lung tissues were collected. In vivo xenograft assay was performed. RESULTS: Expression of miR-CHA1 was downregulated in humanlung cancer cell lines and tissues compared with normal cells and tissues. We identified a putative target gene, XIAP, whose expression was regulated by miR-CHA1 overexpression. XIAP is an inhibitor of apoptosis that represses the activation of caspase 3 and 9. XIAP mRNA and protein levels were directly suppressed by miR-CHA1. XIAP has an important role in carcinogenesis, and previous studies suggest that it may regulate cell survival and proliferation by its anti-apoptotic ability. CONCLUSION: Taken together, miR-CHA1 inhibited cell proliferation and induced apoptosis in vitro and in vivo by targeting XIAP. These data can be applied to identify novel therapeutic targets for lung cancer therapy.