1.Suppression of Aurora-A oncogenic potential by c-Myc downregulation.
Shangbin YANG ; Shun HE ; Xiaobo ZHOU ; Mei LIU ; Hongxia ZHU ; Yihua WANG ; Wei ZHANG ; Shuang YAN ; Lanping QUAN ; Jingfeng BAI ; Ningzhi XU
Experimental & Molecular Medicine 2010;42(11):759-767
The abnormality of serine/threonine kinase Aurora-A is seen in many types of cancers. Although in physiological context it has been shown to play a vital role in cellular mitosis, how this oncogene contributes to tumorigenesis remains unclear. Here we demonstrate that Aurora-A overexpression enhances both the expression level and transcriptional activity of c-Myc. The inhibition of c-Myc expression by RNA interference significantly impaired the oncogenic potential of Aurora-A, resulting in attenuated cellular proliferation and transformation rates as well as fewer centrosomal aberrations. Furthermore, downregulation of c-Myc effectively overcame Aurora-A-induced resistance to cisplatin in esophageal cancer cells. Taken together, our results suggest an important role for c-Myc in mediating the oncogenic activity of Aurora-A, which may in turn allow for future targeting of c-Myc as a potential therapeutic strategy for tumors with Aurora-A overexpression.
Cell Line, Transformed
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Cell Proliferation/drug effects
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Cell Transformation, Neoplastic/drug effects/genetics
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Centro
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Chromo
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Cisplatin/pharmacology
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Down-Regulation
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E
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Gene Expression Regulation, Neoplastic/drug effects
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Humans
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Protein-Serine-Threonine Kinases/genetics/*metabolism
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Proto-Oncogene Proteins c-myc/genetics/*metabolism
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RNA, Small Interfering/genetics
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Transcriptional Activation
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Transgenes/genetics
2.The epitope study on the SARS-CoV nucleocapsid protein.
Shuting LI ; Liang LIN ; Hao WANG ; Jianning YIN ; Yan REN ; Zhe ZHAO ; Jie WEN ; Cuiqi ZHOU ; Xumin ZHANG ; Xiaolei LI ; Jingqiang WANG ; Zhengfeng ZHOU ; Jinxiu LIU ; Jianmin SHAO ; Tingting LEI ; Jianqiu FANG ; Ningzhi XU ; Siqi LIU
Genomics, Proteomics & Bioinformatics 2003;1(3):198-206
The nucleocapsid protein (N protein) has been found to be an antigenic protein in a number of coronaviruses. Whether the N protein in severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is antigenic remains to be elucidated. Using Western blot and Enzyme-linked Immunosorbent Assay (ELISA), the recombinant N proteins and the synthesized peptides derived from the N protein were screened in sera from SARS patients. All patient sera in this study displayed strong positive immunoreactivities against the recombinant N proteins, whereas normal sera gave negative immunoresponses to these proteins, indicating that the N protein of SARS-CoV is an antigenic protein. Furthermore, the epitope sites in the N protein were determined by competition experiments, in which the recombinant proteins or the synthesized peptides competed against the SARS-CoV proteins to bind to the antibodies raised in SARS sera. One epitope site located at the C-terminus was confirmed as the most antigenic region in this protein. A detailed screening of peptide with ELISA demonstrated that the amino sequence from Codons 371 to 407 was the epitope site at the C-terminus of the N protein. Understanding of the epitope sites could be very significant for developing an effective diagnostic approach to SARS.
Blotting, Western
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Enzyme-Linked Immunosorbent Assay
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Epitopes
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chemistry
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immunology
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Humans
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Nucleocapsid Proteins
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chemistry
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immunology
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Peptide Fragments
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chemical synthesis
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Plasmids
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Recombinant Proteins
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immunology
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isolation & purification
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metabolism
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SARS Virus
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genetics
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immunology
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metabolism