Expression And Clinical Significance Of PTEN And P21～(waf1) In Nasopharyngeal Carcinoma

Objective:To investigate the expression and distribution of PTEN and P21waf1 in nasopharyngeal carcinoma, nasopharyngeal precancerous lesion and chronic nasopharyngitis to provide some acceptable indications about the funtion of the tumor suppressor gene PTEN and P21waf1, and to elucidate the relationship between EB virus infection and the expression of the tumor suppressor gene .It may be provide proof for the study of pathogenesis of nasopharyngeal carcinoma and gene therapy.Methods: The study was a single-factor design. 78 cases of NPC as the experimental group, 1 1 cases of precancerous lesion and 25 cases of chronic nasopharyngitis (CN) as the control group were drawn at random .The expression and distribution of PTEN and P21wafl were studied by immunohistochemistry. Results: (l)The positive expression rates of PTEN in CN were significantly higher thanthat in NPC. The expression of PTEN in cells was chiefly located incytoplasm, only few located in nuclear.(2) In NPC ,the positive expression rate of PTEN in I - II phase was significantly higher than that in III- IV phase.(3) In NPC ,the positive expression rate of PTEN declined as the increase of the EB virus infection liter.(4) In NPC with lymph node metastasis, the positive expression rate of PTEN wasn't higher than that in NPC without lymph node metastasis.(5) The positive expression rate of P21wafl in NPC was significantly higher than that in CN. The expression of P21wa" in cells was chiefly located in nuclear, only few located in cytoplasm.(6) In NPC, the positive expression rate of P21watl in III -IV phase was significantly higher than that in I - II phase.(7) In NPC ,the positive expression rate of P21wafl increased with EB virus infection liter's rising.(8) In NPC with lymph node metastasis, the positive expression rate of P2rvatl was significantly higher than that in NPC without lymph node metastasis.Conclusions:The difference of positive rates of PTEN in CN and NPC was significant statistically.(P<0.05), and that in I -II phase and III -IV phase was also significant statistically .On the contrary, The difference of positive rates of P21wafl in CN and NPC was significant statistically.(P<0.05), and that in I -II phase and HI- IV phase was also significant statistically. We can draw contusions that PTEN and P21wafl have close relations with the TNM stage of NPC; PTEN and P21wafl may play a role in the etiology, progression and metastisis of nasopharyngeal carcinoma. They can be used as indexes todetermine the malignant degree and progression of nasopharyngenl carcinoma,and to predict the patients prognosis.