title: MicroRNA-205 suppresses the oral carcinoma oncogenic activity via down-regulation of Axin-2 in KB human oral cancer cell.
abstract: MicroRNA (miRNA) is a small noncoding RNA molecule, 19-25 nucleotides in length, which regulates several pathways including cell development, cell proliferation, carcinogenesis, apoptosis, etc. In this study, the over-expression of microRNA-205 (miR-205) increased the number of apoptotic cells by at least 4 times compared to the control. In addition, over-expressed miRNA in KB oral cancer cells triggered apoptosis via the caspase cascade, including the cleavage of caspase-9, caspase-7, caspase-3, and PARP. Flow cytometry showed that apoptotic cell death was increased significantly by 35.33% in KB oral cancer cells with over-expressed miR-205 compared to the control. The microarray data showed that axis inhibitor protein 2 (Axin2) was down-regulated in KB oral cancer cells transfected with miR-205. In addition, Axin2 was down-regulated by approximately 50% by over-expressed miR-205 at both the mRNA and protein levels. Interestingly, Axin2 was up-regulated in KB oral cancer compared to human normal oral keratinocytes. Furthermore, the cell cytotoxicity and apoptotic population of KB oral cancer cells were increased significantly after Axin2 siRNA transfection. These results suggest that Axin2 is might be as potential oncogene in KB oral cancer cells. The luciferase assay showed that over-expressed miR-205 in KB oral cancer cells suppressed AXIN2 expression through an interaction with its own binding site at AXIN2 3'UTR (64-92). These results suggest that miR-205 is a novel anti-oncogenic miRNA in KB oral cancer cells, and may have potential applications in oral cancer therapy.
authors.affiliation: Oral Biology Research Institute, School of Dentistry, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju, 501-759, Republic of Korea.
authors.forename: Jae-Sung
authors.initials: JS
authors.lastname: Kim
authors.forename: Sun-Young
authors.initials: SY
authors.lastname: Park
authors.forename: Seul Ah
authors.initials: SA
authors.lastname: Lee
authors.forename: Min-Gyeong
authors.initials: MG
authors.lastname: Park
authors.forename: Sun-Kyoung
authors.initials: SK
authors.lastname: Yu
authors.forename: Myoung-Hwa
authors.initials: MH
authors.lastname: Lee
authors.forename: Mi-Ra
authors.initials: MR
authors.lastname: Park
authors.forename: Su-Gwan
authors.initials: SG
authors.lastname: Kim
authors.forename: Ji-Su
authors.initials: JS
authors.lastname: Oh
authors.forename: Sook-Young
authors.initials: SY
authors.lastname: Lee
authors.forename: Chun Sung
authors.initials: CS
authors.lastname: Kim
authors.forename: Heung-Joong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Hong Sung
authors.initials: HS
authors.lastname: Chun
authors.forename: Jin-Soo
authors.initials: JS
authors.lastname: Kim
authors.forename: Sung-Min
authors.initials: SM
authors.lastname: Moon
authors.forename: Do Kyung
authors.initials: DK
authors.lastname: Kim
mesh_terms: D020413:3' Untranslated Regions; D017209:Apoptosis; D060466:Axin Protein / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites; D045744:Cell Line, Tumor; D002470:Cell Survival; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D009062:Mouth Neoplasms; D034622:RNA Interference
chemical_list: D020413:3' Untranslated Regions; D060466:Axin Protein; D035683:MicroRNAs; C491761:AXIN2 protein, human; C534425:MIR205, human