Abstract:

Objective   To determine expression of programmed cell death 5 (PDCD5) in laryngeal squamous cell carcinoma and reveal its possible correlation to clinical parameters. Methods   Expression of mRNA and protein of PDCD 5 were analysed in 41 laryngeal squamous cell carcinoma and 29 normal tissues adjacent to the carcinomas with reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. Immunohistochemistry was also applied to investigate protein expressions of PDCD 5 in squamous cell carcinoma and matched normal tissues. Result   The normal tissues adjacent to tumor lesions expressed higher levels of PDCD5 mRNA, whereas most of laryngeal squamous cell carcinoma expression was reduced or did not expres（P=0.006）. Compared with the normal tissues, most carcinoma exhibited less PDCD5 protein（P=0.012）. By immunohistochemistry, the loss of PDCD5 expression was identified as a frequent event in laryngeal squamous cell carcinoma. Expressions of PDCD5 protein and mRNA were correlated with clinical stages and histological gradings.There was no correlation with age,gender, tumor site or lymph node metastasis. Conclusions   The decrease or absence of PDCD5 expression is a frequent event in laryngeal squamous cell carcinoma, which might contribute to tumor development and progression. 

Key words: Larynx; Squamous Carcinoma; Programmed cell death 5; Apoptosis