title: Functions of MiRNA-128 on the regulation of head and neck squamous cell carcinoma growth and apoptosis.
abstract: BACKGROUND
  Incidence of head and neck squamous cell carcinoma (HNSCC) has continuously increased in past years while its survival rate has not been significantly improved. There is a critical need to better understand the genetic regulation of HNSCC tumorigenesis and progression. In this study, we comprehensively analyzed the function of miRNA-128 (miR-128) in the regulation of HNSCC growth and its putative targets in vitro and in vivo systems.
  
  
  METHODS
  The function and targets of miR-128 were investigated in human HNSCC cell lines (JHU-13 and JHU-22), which were stably transfected with the miR-128 gene using a lentiviral delivery system. The expression levels of miR-128 and its targeted proteins were analyzed with qRT-PCR, Western blotting and flow cytometry. The binding capacity of miRNA-128 to its putative targets was determined using a luciferase report assay. MTT, colony formation, and a tumor xenograft model further evaluated the effects of miR-128 on HNSCC growth.
  
  
  RESULTS
  We generated two miR-128 stably transfected human HNSCC cell lines (JHU-13miR-128 and JHU-22miR-128). Enforced expression of miR-128 was detected in both cultured JHU-13miR-128 and JHU-22miR-128 cell lines, approximately seventeen to twenty folds higher than in vector control cell lines. miRNA-128 was able to bind with the 3'-untranslated regions of BMI-1, BAG-2, BAX, H3f3b, and Paip2 mRNAs, resulting in significant reduction of the targeted protein levels. We found that upregulated miR-128 expression significantly inhibited both JHU-13miR-128 and JHU-22miR-128 cell viability approximately 20 to 40%, and the JHU-22miR-128 tumor xenograft growth compared to the vector control groups.
  
  
  CONCLUSIONS
  miR-128 acted as a tumor suppressor inhibiting the HNSCC growth by directly mediating the expression of putative targets. Our results provide a better understanding of miRNA-128 function and its potential targets, which may be valuable for developing novel diagnostic markers and targeted therapy.
authors.affiliation: Department of Genetics and Human Genetics, Howard University, Washington, DC, United States of America.
authors.forename: Belinda
authors.initials: B
authors.lastname: Hauser
authors.affiliation: Department of Oral Pathology, Howard University, Washington DC, United States of America.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Department of Oral Pathology, Howard University, Washington DC, United States of America.
authors.forename: Xiaowu
authors.initials: X
authors.lastname: Pang
authors.affiliation: Zhejiang Cancer Research Institute, Hangzhou, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Ling
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Howard University, Washington, DC, United States of America.
authors.forename: Ernest
authors.initials: E
authors.lastname: Myers
authors.affiliation: Department of Radiology, Howard University, Washington DC, United States of America; Cancer Center, Howard University, Washington, District of Columbia, United States of America.
authors.forename: Paul
authors.initials: P
authors.lastname: Wang
authors.affiliation: Departments of Otolaryngology-Head and Neck Surgery, and Head & Neck Research Division, Johns Hopkins University, Baltimore, Maryland, United states of America.
authors.forename: Joseph
authors.initials: J
authors.lastname: Califano
authors.affiliation: Department of Genetics and Human Genetics, Howard University, Washington, DC, United States of America; Department of Oral Pathology, Howard University, Washington DC, United States of America; Cancer Center, Howard University, Washington, District of Columbia, United States of America.
authors.forename: Xinbin
authors.initials: X
authors.lastname: Gu
mesh_terms: D000818:Animals; D017209:Apoptosis; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D006258:Head and Neck Neoplasms / Q000235:genetics* / Q000473:pathology*; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D035683:MicroRNAs / Q000235:genetics*; D018832:Molecular Chaperones / Q000235:genetics; D009368:Neoplasm Transplantation; D063150:Polycomb Repressive Complex 1 / Q000235:genetics; D016601:RNA-Binding Proteins / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics; D051028:bcl-2-Associated X Protein / Q000235:genetics
chemical_list: C492980:BAG2 protein, human; C494826:BAX protein, human; C069077:BMI1 protein, human; C545189:MIRN128 microRNA, human; D035683:MicroRNAs; D018832:Molecular Chaperones; C488448:PAIP2 protein, human; D016601:RNA-Binding Proteins; D012097:Repressor Proteins; D051028:bcl-2-Associated X Protein; D063150:Polycomb Repressive Complex 1