食管鳞癌标本中C-MYC、Rb、P16和EGFR表达的定位分析

Topographical analysis of Rb,P16,C-MYC and EGFR protein expression in esophageal squamous cell carcinoma specimens

目的 :研究C MYC、Rb、P1 6及EGFR蛋白在食管鳞癌标本中的定位表达。方法 :采用免疫组化方法定位分析 4 5例原发性食管鳞癌大体标本中C MYC、Rb、P1 6及EGFR蛋白的表达。将食管标本固定并沿食管长轴取成大小为 2 .0cm× 0 .5cm的若干段组织。根据组织学检查结果 ,绘图显示每例食管标本不同病变及各种蛋白在不同区域 (正常黏膜、单纯增生、不典型增生、原位癌及浸润癌 )中的分布情况。结果 :C MYC、EGFR在食管癌自然病史中呈现渐进性高表达 ,而Rb则在其中呈现渐进性低表达 ,P1 6表达则无渐进性。EGFR、P1 6表达在单纯增生和不典型增生中差异有统计学意义 ;而C MYC、Rb则在原位癌与浸润癌中差异有统计学意义。此外 ,Rb与C MYC在食管癌组织中的表达呈负相关 (P <0 .0 5 )。绘图显示出每一例食管癌大体标本中同一区域不同肿瘤标记物表达的差异、同一种肿瘤标记物在不同区域表达的差异及同一种肿瘤标记物在同一种黏膜病变中表达的差异。结论 :EGFR、p1 6基因的改变可能是食管癌发生发展过程中的早期事件 ;而c myc、Rb基因的改变可能是其中的中晚期事件 ,并赋予肿瘤细胞更多的恶性生物学行为 ;上述基因在食管癌发生发展中存在相互协调作用。

Aim:To observe the expression of Rb,P16,C MYC and EGFR proteins in esophageal squamous cell carcinoma specimens. Methods: Immunohistochemistry was used to topographically analyze the expression of Rb,P16,C MYC,and EGFR protein in 45 cases of esophageal squamous cell carcinoma in situ specimens. Specimens were fixed in 10% formalin and then the entire resected esophagus was cut into longitudinal sections (2.0 cm in the length and 0.5 cm in the width) and embedded in paraffin. For each specimen, a diagram showing the topographic location of cancerous and precancerous lesions was generated. Results: Stepwise over expression of C MYC and EGFR, reduction of Rb expression and dysregulation of P16 were observed in the esophageal carcinogenesis. Significant differences in expression of EGFR ( P < 0.05) and P16 ( P <0.001) were observed between hyperplasia and dysplasia tissues; expression of C MYC ( P <0.05) and Rb ( P <0.05) had significant difference between the invasive carcinoma and the carcinoma in situ. Furthermore, the expression of Rb was negatively correlated with that of C MYC ( P <0.05). The diagrams could directly show the differences of different markers in the same lesion, the same marker in different lesions and the same marker in the same lesion. Conclusion: Alteration of EGFR and P16 gene expression may be the early event of the esophageal carcinogenesis; while alteration of c-MYC and Rb gene expression is the later event of carcinogenesis. Rb and C-MYC genes may cooperate with each other in esophageal carcinogenesis. These novel diagrams can indicate more latent information.