Porebska I, Harlozińska A, Bojarowski T
Department of Tumor Immunology, Wroclaw University of Medicine, Wroclaw, Poland.
Tumour Biol. 2000 Mar-Apr;21(2):105-15. doi: 10.1159/000030116.
The overexpression of three growth factor receptors: epidermal growth factor receptor (EGFR), ERB B2 and ERB B3 was evaluated immunohistochemically in 77 malignant and 15 benign colorectal neoplasms considering clinicopathological variables (histological structure, grade of differentiation, tumor localization, clinical stage of the disease). The relationship between the coexpression of EGFR-related proteins in individual patients was also evaluated. EGFR expression was revealed in comparable percentages of colorectal adenoma and in adenocarcinoma cases (80% and 70%) while ERB B2 expression was detectable more frequently in adenoma than in adenocarcinoma cases (87% and 54%). The presence of ERB B3 was observed in a higher percentage of adenocarcinoma than adenoma cases (65% and 40%). There was no correlation between the expression of studied tyrosine kinase receptors and histological grade or Dukes' clinical stage and localization (proximal or distal) of colorectal adenocarcinoma. The incidence of EGFR and ERB B2 expression was higher in tubulovillous (100% for both receptors) than in tubular adenomas (63% and 75%), while the ERB B3 receptor was revealed more frequently in tubular than in tubulovillous neoplasms (50% and 28%). These differences appeared to be statistically nonsignificant. The concomitant expression of two growth factor receptors was observed in a higher percentage of colorectal adenomas than adenocarcinomas, and the coexistence of three growth factors was revealed in comparable percentages in malignant and benign colorectal tumors. Our results support the promotional rather than direct transformational role for the EGFR supergene family in colorectal tumorigenesis. The frequently observed coexpression of more than one EGFR-related protein in colorectal neoplasms indicates the possible cooperation of these receptors in mitogenic signaling transduction, facilitating the development and maintenance of the malignant phenotype.
采用免疫组织化学方法，在77例恶性和15例良性结肠直肠肿瘤中评估了三种生长因子受体，即表皮生长因子受体（EGFR）、ERB B2和ERB B3的过表达情况，并考虑了临床病理变量（组织结构、分化程度、肿瘤定位、疾病临床分期）。还评估了个体患者中EGFR相关蛋白共表达之间的关系。在结肠直肠腺瘤和腺癌病例中，EGFR表达的比例相当（分别为80%和70%），而ERB B2在腺瘤中的表达比腺癌中更常见（分别为87%和54%）。腺癌中ERB B3的存在比例高于腺瘤（分别为65%和40%）。所研究的酪氨酸激酶受体的表达与结肠直肠腺癌的组织学分级、Dukes临床分期及定位（近端或远端）之间无相关性。EGFR和ERB B2在绒毛状腺瘤中的表达发生率高于管状腺瘤（两种受体均为100%），而ERB B3受体在管状肿瘤中比在绒毛状肿瘤中更常见（分别为50%和28%）。这些差异似乎无统计学意义。两种生长因子受体的同时表达在结肠直肠腺瘤中的比例高于腺癌，三种生长因子的共存情况在恶性和良性结肠直肠肿瘤中的比例相当。我们的结果支持EGFR超基因家族在结肠直肠肿瘤发生中起促进作用而非直接转化作用。在结肠直肠肿瘤中经常观察到一种以上EGFR相关蛋白的共表达，这表明这些受体可能在有丝分裂信号转导中协同作用，促进恶性表型的发展和维持。
