CCN2 and nasopharyngeal carcinoma: The Mann-Whitney test of positive rates in NPC and NP samples indicated that BIRC5 protein expression was significantly higher in NPC (P < 0.004) compared to NP samples, while TGFBR2 and CTGF were significantly lower in NPC (P < 0.002 and 0.001 respectively) compared to NP samples, supporting the reliability of the array data.