Effect Of Microrna-210 On Radiosensitivity In Nasopharyngeal Carcinoma Cells

PART 1 Toestablish the radiation-resistant nasopharyngeal carcinoma cellsObjective: Toestablish the radiation-resistant nasopharyngeal carcinoma cells(CNE-2R). The mi RNA microarray was used for detecting mi RNA expression profiles of the parental cell(CNE-2) cells and CNE-2R cells. In order to further study the relationship between mi RNAs and the radiosensitivity of nasopharyngeal carcinoma.Methods: The radiation-resistant nasopharyngeal carcinoma cells(CNE-2R) were established bydose gradient method. Cell cycle of CNE-2and CNE-2R cells were detected by flow cytometry, the survival fraction of cells were detected by clone formation assay.The differences of radiosensitivity between CNE-2 and CNE-2R cells were detected by cell cycle assay, cell viability assay andcolony formation assay.Mi RNA microarrays used for detecting mi RNA expression profiles of the CNE-2and CNE-2R cells.Results: The percentage of CNE-2 cells in G2/M phase was significantly greater than CNE-2R cells. At the same time, determination of cell viabilities showed that the CNE-2R cells had lower decreases in viability than the CNE-2 cells when irradiated with 0, 4,8,and 12 Gyof radiation. Furthermore, the radiosensitivities of the CNE-2 and CNE-2R cells were compared using the colony formation assay, which showed that the CNE-2R cells had a greater percentage of radioresistant cells than the CNE-2 cells. There were 92 mi RNAs expression remarkable changed over>2 fold in CNE-2R cell lines which we established, compared with CNE-2, andmi R-210 was verified by q PCR.Conclusions:There are many differencesmi RNAs between the acquiredradioresistant CNE-2R cells and their parental CNE-2 cells. The expression of mi R-210 in CNE-2R cells was 247.25-fold higher than the expression in CNE-2 cells.PART 2 Micro RNA-210 negatively regulatesthe radiosensitivityof nasopharyngeal carcinoma cellsObjective:The aim was to investigate the effect of mi R-210 on NPC cells, and mi R-210 may therefore have therapeutic potential forthetreatment of radiation resistance.Methods: CNE-2R cells were transfected with LV-hsa-mi R-210-inhibition, and CNE-2 cells were transfected with LV-hsa-mi R-210.The expression of mi R-210 was confirmed by reverse transcription-polymerase chain reaction. Cell cycle and apoptosisof CNE-2,CNE-2R-mi R-210-inhibition, CNE-2-mi R-210, CNE-2R cells were detected by flow cytometry. The cell viabilities were detected by cell viability assay. The survival fractions of cells were detected by clone formation assay.Results: The percentages of CNE-2R-mi R-210-inhibition and CNE-2cells in the G2/M phase were higher than in the CNE-2R and CNE-2-mi R-210 cells, and the percentages of cells in S phase were lower than in the CNE-2R and CNE-2-mi R-210 cells. After 4Gy of radiation,CNE-2R-mi R-210-inhibition and CNE-2 cells, which express low levels of mi R-210, had a higher apoptosis rate than CNE-2R and CNE-2-mi R-210 cells. After 4, 8, and 12 Gy of radiation, cell proliferation ability and survival fraction of CNE-2R-mi R-210-inhibition cells were lower than those of CNE-2R and CNE-2-mi R-210 cells, and similar to those of CNE-2cells.Conclusions: Together, these findings strongly suggest thatmi R-210 negatively regulates the radiosensitivity of NPC cells, and may thereforehave therapeutic potential for the treatment of radiation resistance.