ABSTRACT
<p><b>OBJECTIVE</b>To explore the expression of CASP8 and its clinical significance in nasopharyngeal carcinoma (NPC).</p><p><b>METHODS</b>The differentially expressed genes between pooled NPC tissues and non-cancerous nasopharyngeal (NP) tissues were screened using 8 microarrays. Real-time PCR and immunohistochemistry were used to validate the detection results of CASP8 expression in NPC, and the correlation of CASP8 expression to the clinical characteristics was analyzed in the NPC cases.</p><p><b>RESULTS</b>Real-time PCR confirmed a reduced expression of CASP8 mRNA level in NPC tissues (P<0.0001), which was consistent with the microarray data. Immunohistochemistry indicated that CASP8 protein expression was also significantly down-regulated in NPC tissue compared to that in the non-cancerous nasopharyngeal tissues (P=0.02). The reduction of CASP8 expression was inversely correlated to lymph node metastasis (P=0.002) and the clinical stages (P=0.026) of NPC.</p><p><b>CONCLUSION</b>Decreased CASP8 expression is an unfavorable factor that promotes the development and progression of NPC.</p>