mRNA expression profiling of ebv-miR-BART7-expressing NPC cells

Nasopharyngeal carcinoma (NPC) is endemic in Southeast Asia and southern China. The primary treatment for NPC is radiotherapy. Despite of the encouraging results of radiotherapy, local recurrence or distant metastases of NPC after the initial therapy is frequently found due to radioresistance. Therefore, there is an urgent need to identify genes that control radiosensitivty, aiming to reduce disease recurrence. Epstein-Barr virus (EBV) infection was closely associated with undifferentiated NPC. EBV-encoded microRNAs (miRNAs) played crucial roles in the pathogenesis of NPC. Ebv-miR-BART7 belongs to the 44 EBV BART miRNAs and was found to be up-regulated in NPC tissues and plasma. Forced expression of ebv-miR-BART7 enhanced the radiosensitivity of NPC cells. However, the mechanisms underlying the sensitizing effect of ebv-miR-BART7 on radiation remain largely unknown. Given that miRNA exerts biological functions by regulating its targets, we used microarray to identify the targets of ebv-miR-BART7 that regulate radiosensitivity of NPC cells. NPC HONE1 cells were transfected with ebv-miR-BART7 mimic or negative control siRNA. The experiment was done in duplicate. Then, HONE1 cells were irradiated at 4 gray. RNA were extracted and hybridized on Affymetrix microarrays.