title: Effects of microRNA-221/222 on cell proliferation and apoptosis in prostate cancer cells.
abstract: OBJECTIVE
  To investigate the role of miR-221/222 in cell proliferation and apoptosis in human prostate cancer cells, and examine the effects of miR-221/222 on caspase-10 expression.
  
  
  METHODS
  Prostate cancer cells were transfected with miR-221/222 mimics or inhibitors. Cell proliferation was assessed by MTT assay. The expression levels of miR-221/222 were detected with quantitative real-time PCR. Apoptosis was induced with TNF-α/CHX treatment, and evaluated by Hoechst 33342 staining, propidium iodide (PI) flow cytometric analysis, caspase-3 activity measurement, and Western blot analysis. Luciferase activity assay, quantitative real-time PCR, and Western blot were performed to evaluate the effects of miR-221/222 on caspase-10 expression.
  
  
  RESULTS
  Our results showed that miR-221/222 could promote the proliferation of prostate cancer cells, including LNCaP and PC3 cells. After transfection and apoptosis induction, Hoechst 33342 staining and PI flow cytometric assay showed that apoptosis was dramatically decreased in prostate cancer cells treated with miR-221/222 mimics. Moreover, caspase-3 activity was dramatically decreased, and the cleaved forms of caspase-3 were reduced, in the miR-221/222 mimic-treated group. On the contrary, miR-221/222 knockdown sensitized the prostate cancer cells to TNF-α/CHX-induced apoptosis. In addition, a negative correlation was observed between the expressions of miR-221/222 and caspase-10 in prostate cancer cells. miR-221/222 could repress the expression of caspase-10, which was confirmed by the luciferase reporter assay.
  
  
  CONCLUSIONS
  miR-221/222 promote cell proliferation and repress apoptosis, through suppressing caspase-10, in prostate cancer cells. Our results provide promising evidence for the miRNA-based therapeutic strategy of prostate cancers.
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical School of Shandong University, Jinan 250012, Shandong, China; Jinan Infectious Disease Hospital, Jinan 250012, Shandong, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical School of Shandong University, Jinan 250012, Shandong, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical School of Shandong University, Jinan 250012, Shandong, China.
authors.forename: Chaoyang
authors.initials: C
authors.lastname: Li
authors.affiliation: Medical School of Shandong University, Jinan 250012, Shandong, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Xue
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical School of Shandong University, Jinan 250012, Shandong, China.
authors.forename: Shihu
authors.initials: S
authors.lastname: Zhao
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical School of Shandong University, Jinan 250012, Shandong, China.
authors.forename: Panpan
authors.initials: P
authors.lastname: Zhan
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical School of Shandong University, Jinan 250012, Shandong, China.
authors.forename: Yani
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical School of Shandong University, Jinan 250012, Shandong, China.
authors.forename: Pengju
authors.initials: P
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical School of Shandong University, Jinan 250012, Shandong, China.
authors.forename: Anli
authors.initials: A
authors.lastname: Jiang
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical School of Shandong University, Jinan 250012, Shandong, China. Electronic address: chenweiwen@sdu.edu.cn.
authors.forename: Weiwen
authors.initials: W
authors.lastname: Chen
mesh_terms: D017209:Apoptosis; D053455:Caspase 10 / Q000235:genetics*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000473:pathology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D053455:Caspase 10; D035683:MicroRNAs; D014409:Tumor Necrosis Factor-alpha; C525709:MIR221, human; C525710:MIR222, human; C506438:CASP10 protein, human
keywords: Apoptosis; Caspase-10; Cell proliferation; Prostate cancer; miR-221/222