Wilson Katherine S, Roberts Helen, Leek Russell, Harris Adrian L, Geradts Joseph
Nuffield Department of Clinical Laboratory Sciences, University of Oxford, Oxford, United Kingdom.
Am J Pathol. 2002 Oct;161(4):1171-85. doi: 10.1016/S0002-9440(10)64394-5.
Overexpression of the oncogene HER2/neu (c-erbB-2) occurs in up to 30% of breast cancers and is correlated with reduced survival, especially in node-positive disease. The aim of this study was to identify genes associated with the aggressive phenotype of HER2/neu-positive breast cancer cells using cDNA microarrays. RNA was extracted from three HER2/neu-positive and three HER2/neu-negative breast cancer cell lines. Pooled RNA was hybridized in duplicate to the breast specific microarray filters from Research Genetics containing 5184 unique cDNAs. Subsequently, a similar comparison was performed for pooled RNAs from 10 node-positive, ER-positive invasive ductal carcinomas, half of which were HER2/neu overexpressers. In HER2/neu overexpressing breast cancer cell lines, 90 (1.7%) genes were up-regulated and 46 (0.9%) were down-regulated, compared to cell lines with low HER2/neu protein levels. In contrast, in HER2/neu overexpressing primary breast cancers, more genes were down-regulated (N = 132, 2.5%) than up-regulated (N = 19, 0.4%). Many of the differentially expressed genes have previously not been known to play a role in human neoplasia, and some of them may represent novel tumor suppressor or oncogenes. No genes were up-regulated, and only a small number of genes were down-regulated both in cell lines and in carcinomas with high HER2/neu protein levels. These included transforming acidic coiled-coil containing protein 1, glycogen phosphorylase BB, complement 1q and one EST. The differential expression of select genes was confirmed by Northern blotting (trefoil factor 3) or by immunocytochemistry (glycogen phosphorylase BB, vimentin, KAI1). In an extended validation study, 18 of 41 ER-negative, but none of 46 ER-positive, breast carcinomas were found to express vimentin, and all but one of the vimentin-positive tumors were confined to the HER2/neu-negative subgroup (P = 0.0019). Our findings support an important role of the mammary stroma in determining the clinical breast cancer phenotype.
致癌基因HER2/neu（c-erbB-2）在高达30%的乳腺癌中过表达，且与生存率降低相关，尤其是在淋巴结阳性疾病中。本研究的目的是使用cDNA微阵列鉴定与HER2/neu阳性乳腺癌细胞侵袭性表型相关的基因。从三个HER2/neu阳性和三个HER2/neu阴性乳腺癌细胞系中提取RNA。将混合RNA一式两份与Research Genetics公司的乳腺特异性微阵列滤膜杂交，该滤膜包含5184个独特的cDNA。随后，对来自10例淋巴结阳性、雌激素受体（ER）阳性浸润性导管癌的混合RNA进行了类似比较，其中一半为HER2/neu过表达者。与HER2/neu蛋白水平低的细胞系相比，在HER2/neu过表达的乳腺癌细胞系中，90个（1.7%）基因上调，46个（0.9%）基因下调。相比之下，在HER2/neu过表达的原发性乳腺癌中，下调的基因（N = 132，2.5%）比上调的基因（N = 19，0.4%）更多。许多差异表达基因以前未知在人类肿瘤形成中起作用，其中一些可能代表新的肿瘤抑制基因或致癌基因。在HER2/neu蛋白水平高的细胞系和癌组织中，没有基因上调，只有少数基因下调。这些基因包括含转化酸性卷曲螺旋蛋白1、糖原磷酸化酶BB、补体1q和一个EST。通过Northern印迹法（三叶因子3）或免疫细胞化学法（糖原磷酸化酶BB、波形蛋白、KAI1）证实了所选基因的差异表达。在一项扩展的验证研究中，发现41例ER阴性乳腺癌中有18例表达波形蛋白，而46例ER阳性乳腺癌中无一例表达波形蛋白，并且除1例之外，所有波形蛋白阳性肿瘤均局限于HER2/neu阴性亚组（P = 0.0019）。我们的研究结果支持乳腺基质在决定临床乳腺癌表型中起重要作用。
