MicroRNA-21in Papillary Thyroid Cancer In TPC-1

BackgroundmicroRNA-21(miR-21) is one of the earliest discovered tiny RNA, it is located the17q23.2chromosome fragment FRA17B the brittle region has independent transcription units. In recent years research:miR-21showed overexpression in breast cancer, lung cancer, stomach cancer, glioblastoma cell tumor, pancreatic neuroendocrine tumors, pancreatic cancer, bile duct cancer, liver cancer, prostate cancer and other cancers. Especially in the human brain glioblastoma (high grade), miR-21expression levels can be higher than other non-cancerous tissue from6to10times; However, in normal adult white matter, miR-21also The level of expression. Seen in this light, the expression of miR-21is not particularly obvious specificity. Numerous studies show that:miR-21to promote tumor cell transformation function is to rely on the inhibition of tumor suppressor genes, that is, programmed cell death factor4to achieve. In miR-21in human breast cancer and a significant rise, but also with tumor stage, tumor cell proliferation index is closely related, which prompted us miR-21may play an oncogene in tumor development role. Reported a direct target of miR-21in different types of tumors. Its tumor suppressor function, can inhibit translation with the translation initiation factor eIF4A and eIF4G’s binding interactions, thereby inhibiting the formation of the translational complex, programmed cell death factor4(PDCD4) is found in recent years, a new type of tumor inhibitor, it is P13K/Akt signaling pathways downstream molecules, PDCD4through inhibition of mitogen activated protein kinase kinase kinase kinase1(MAP4K1), which is upstream of JNK (Jun N-terminal kinase) inhibitor of metalloproteinase activity Expression lock, the purpose is to inhibit the invasion and vascular inner colon. The PDCD4reduce the expression of E-cadherin, and activate P-catenin/Tcf (T cell factor) in colon tumor cells is dependent transcriptional repression and AP-1-dependent transcription. These results provide a molecular explanation for PDCD4inhibition of tumor invasion. PDCD4inhibit tumor formation, to promote the role of apoptosis.In this study, by the TPC-1papillary thyroid carcinoma transfected cells were transiently transfected with miR-21, followed by immunohistochemistry and flow cytometry to detect cell apoptosis and proliferation, and PDCD4expression. To explore the relationship between the two and the mechanism of action in papillary thyroid cancer.ObjectiveLiposomal transfection reagent Lipofectamine2000TM transient transfection the eukaryotic recombinant the plasmid pEZX-eGFP-miR-21, the plasmid with high expression in papillary thyroid cancer in TPC-1, the test for the next furtherstudy of miR-21in TPC-1papillary thyroid cancer in apoptosis, metastasis, and lay a solid foundation for the role in the proliferation of its gene regulation mechanism.Methods(1) transiently transfected with Lipofectamine2000TM miR-21to papillary thyroid cancer in TPC-1;(2) and identification of recombinant plasmids after transient transfection pEZX-eGFP-miR-21, immunohistochemistry to detect the expression of transfected PDCD4immunohistochemical method;(3) using the MTT assay transient transfection of the miR-21TPC-1cell proliferation; observed before and after transfection cell proliferation curves(4) the use of flow cytometry to detect transientTPC-1cell apoptosis after transfection, change the image of the apoptosis observed after transfection.Results(1) liposomes transmitted reagents miR-21transfected TPC-1cells transiently transfected with papillary thyroid cancer in TPC-1, a larger proportion of spindle cell expression of green fluorescent protein. (2) immunohistochemical detection of transfected transiently transfected with miR-21group, the the transfection group of cell membrane was tan of PDCD4expression was significantly higher.(3) MTT assay miR-21gene transfectionafter can significantly promote the TPC-1cell proliferation. Transfection group and blank plasmid group cell number has increased faster but the group transfected TPC-1cell proliferation.(P<0.05).(4) transfection of miR-21cell apoptosis rate of the control group, there are significant differences between the apoptosis rate is significantly reduced.ConclusionTransient transfection pEZX-eGFP-miR-21after transfection promoted cell proliferation, decreased apoptosis, suggesting that high expression of miR-21can promote the development of papillary thyroid carcinoma, and this effect may be through reduced PDCD4protein expression to achieve.