Correlation Of PCNA, P27, P53, P16 Protein And Gene Expression With Clinicopathologic Parameters And Prognosis Of Hypopharyngeal Carcinoma

Obstive To investigate the expression of PCNA, p27, p53 and p16 protein and gene mRNA in squamous cell carcinoma of the hypopharynx and study the relationship between them and clinicopathologic parameters and prognosis of the hypopharyngeal carcinoma and between the expression of PCNA, p27, p53, p16 protein and that of gene.Methods Paraffin-embedded tissue sections of 48 cases of of primary hypopharyngeal squamous carcinomas diagnosed and treated surgically from January in 1994 to January in 2000 as well as in 15 cases of common squamous epithelial mucosa were detected for PCNA, p27, p53, p16 protein and gene expression respectively by immunohistochemistry and by in-situ hybridisation.Results The rate of the overexpression of PCNA and p53 protein was notablely higher in the hypopharyngeal cancer tissue than in the common squamous epithelial tissue, but the loss of the expression of p27 and pi6 protein was significantly related to hypopharyngeal carcinoma(P<0.05). Neither the expression of PCNA, p27, p53 or p16 protein related to the primary site of hypopharyngeal carcinoma. p27 protein immunoreactivity correlated negatively with clinical stage (Spearman's correlation coefficient, P=0.006), cervical lymph node metastasis, and poor prognosis, but positively with histological differentiation (Spearman's correlation coefficient, P=0.008). There was a negative correlation between the expression of pi6 and clinical stage (Spearman's correlation coefficient, P=0.009).The loss of p16 protein expression was related to a shortened survical period. p53 protein overexpression positively correlated with clinical stage, cervical lymph node metastasis, recurrence and poor prognosis. The overexpression of PCNA was related to an advanced clinical stage, poor histological differentiation, recurrence and poor prognosis, but not to metastasis of cervical lymph nodes. The expression of p53 protein positively correlated with that of PCNA, butnegatively with that of p27 protein. p16 and p53 gene expression was notablely higher in the hypopharyngeal cancer tissue than that in the common squamous epithelial tissue,but to PCNA gene,the result was reverse. There was a coincidence between the expression of p27, p16 or PCNA mRNA and that of respective protein. The loss of the expression p16 gene was significantly related to an advanced clinical stage and poor prognosis of the patients with hypopharyngeal cancer. There was no notetable correlation between either p27 or p53 gene expression and clinicopathologic parameters.Conclusions The expression of PCNA, p27, p16 and p53 protein may provide a reference in evaluating proliferating speed, malignancy level, clinicopathological behavor of hypopharyngeal carcinoma and prognsis of the patients. The expression of PCNA, p27, and p16 protein was almost indentical with that of respective mRNA. In hypopharyngeal cancer, it was unusual that p27 gene altered, which may occur during post-transcription. In addition, PCNA expression may provide a maker for early-period diagnosis for hypopharyngeal carcinoma.