宫颈癌组织中P16和HPV16/18E7的表达及意义

EXPRESSION OF P16 AND HPV16/18 E7 IN CERVICAL CANCER

①目的 研究宫颈癌组织中抑癌基因p16mRNA和蛋白质的表达 ,以及与HPV16 / 18E7表达的关系。②方法 采用聚合酶链反应 (PCR)技术检测 4 5例宫颈浸润癌组织、12例宫颈原位癌组织和 2 0例正常宫颈组织中HPV16 / 18的感染情况 ;采用RT PCR技术检测上述标本中HPV16 / 18阳性者E7mRNA的表达水平及所有标本中p16mRNA表达水平 ;采用免疫组化技术进一步检测HPV16 / 18E7、P16蛋白的表达情况。③结果 宫颈原位癌和浸润癌HPV16 / 18的感染率、HPV16 / 18E7mRNA和蛋白表达阳性率明显高于正常宫颈组织 ,差异有显著性 (χ2 =5 .12～ 15 .78,P <0 .0 5、0 .0 1) ,原位癌和浸润癌组之间比较差异无显著性 (χ2 =0 .119、0 .0 0 0 ,P >0 .0 5 ) ;原位癌和浸润癌 p16mRNA的相对表达量明显高于正常宫颈 ,差异有显著性 (F =5 .4 12 ,q =4 .12 5、5 .5 19,P<0 .0 5 ) ;HPV16 / 18E7阳性组 p16mRNA的表达阳性率明显高于阴性组 ,差异有显著性 (t=4 .12 7,P <0 .0 1) ;P16蛋白在宫颈原位癌和浸润癌组织中呈现过表达 ,在正常组织中为阴性表达或弱表达 ;p16mRNA的相对表达量与HPV16 / 18E7mRNA的相对表达量呈显著正相关 (r=0 .813,P <0 .0 5 ) ;P16蛋白的过表达与HPV16 / 18E7蛋白表达有相关关系 (χ2 =8.95 9,P <0 .0 1) ;

Objective To study the expression of tumor suppressor gene p16 in cervical cancer, and to analyze its relationship with expression of HPV16/18 E7. Methods HPV16/18 infection was detected using PCR method in tissues in 45 cases with infiltrated cancer(IC), 12 with cancer in situ(CIS) and 12 normal cervical tissue, in which, E7 mRNA expression was detected in HPV16/18-positive samples, and p16 and HPV16/18 E7 assessed in all samples by reverse transcription PCR and immunohistological technology. Results The infection rate and expression of HPV16/18 E7 in CIN and IC were higher than those in the normal cervical tissue(χ 2=5.12-15.78;P<0.05,0.01). The difference of expressions of p16 mRNA between CIS and IC was not significant (χ 2=0.119,0.000;P>0.05). Expression of p16 in HPV16/18 E7 positive tissue was higher than in normal tissue (t=4.127,P<0.01). p16 was over expressed in both CIS an IC, while expression in normal tissue was either weak or negative. The relative expressions between p16 mRNA and HPV16/18 E7 mRNA showed positive correlation(r=0.813,P<0.01). The over expression of P16 showed correlation to HPV16/18 E7(χ 2=8.959,P<0.01). The expressions of HPV16/18 E7 and p16 had nothing to do with the histological grading, lymph node metastasis, and size of the tumor as well as the patient's age (P>0.05). Conclusion Overexpression of tumor suppressor p16 occurs in early phase of the disease and precancerous lesions, which may be used to screen and early diagnose cervical cancer.