Institute of Pathology, Medical University of Graz, Austria.
Histopathology. 2011 Aug;59(2):225-34. doi: 10.1111/j.1365-2559.2011.03694.x.
To assess the prevalence of keratin 7 (K7) expression in colorectal cancer and to correlate findings with clinicopathological parameters and patients' outcome.
A total of 370 patients were evaluated for K7 expression by immunohistochemistry using a tissue microarray technique. K7 expression was scored semiquantitatively as either focal (<10%), moderate (10-50%) or extensive (>50%). In all, 32 (9%) tumours were immunoreactive for K7, with five cases showing extensive, four moderate and 23 focal expression, respectively. K7 expression was associated with poor tumour differentiation (P = 0.005) and the extent of tumour budding (P = 0.02). In whole sections, K7 immunoreactivity prevailed in single cells and small clusters of cells at the invasion front. Analysis of serial sections showed that K7-positive cells colocalized with keratin 20, whereas they lacked immunoreactivity for E-cadherin, MUC2 and MIB-1. Disease progression occurred in 52% of patients with K7-positive tumours and 41% with K7-negative tumours (P = 0.19); 48% of patients with K7-positive tumours but only 33% with K7-negative tumours died of disease (P = 0.06).
Aberrant expression of K7 in budding cancer cells represents a modification of the epithelial phenotype ('epithelial-epithelial transition': EET) which may be linked to gains in motility and invasive potential.
评估角蛋白 7（K7）在结直肠癌中的表达，并将研究结果与临床病理参数和患者预后相关联。
采用组织微阵列技术，通过免疫组织化学方法对 370 例患者的 K7 表达进行评估。K7 表达的评分采用半定量评分，分为局灶性（<10%）、中度（10-50%）或广泛（>50%）。共有 32 例（9%）肿瘤对 K7 呈免疫反应性，其中 5 例表现为广泛表达，4 例中度表达，23 例局灶性表达。K7 表达与肿瘤分化不良（P=0.005）和肿瘤芽出程度（P=0.02）相关。在全切片中，K7 免疫反应性在侵袭前沿的单个细胞和小细胞簇中占优势。对连续切片的分析表明，K7 阳性细胞与角蛋白 20 共定位，而它们缺乏 E-钙黏蛋白、MUC2 和 MIB-1 的免疫反应性。在 K7 阳性肿瘤患者中，52%发生疾病进展，在 K7 阴性肿瘤患者中，41%发生疾病进展（P=0.19）；在 K7 阳性肿瘤患者中，48%死亡，而在 K7 阴性肿瘤患者中，只有 33%死亡（P=0.06）。
芽出癌细胞中 K7 的异常表达代表上皮表型的改变（“上皮-上皮转变”：EET），这可能与运动和侵袭潜能的增加有关。
