Brachyury is a transcription factor of the T-box family typically expressed in notochord and chordoma. Some studies report brachyury as highly specific for chordoma, whereas others have concluded that brachyury is expressed in many types of common carcinomas by reverse transcription polymerase chain reaction and immunohistochemistry and could be involved in the epithelial-mesenchymal transition and metastatic process. In this study, we immunohistochemically evaluated 5229 different tumors for nuclear brachyury expression using a new rabbit monoclonal antibody and automated immunostaining (Leica Bond Max). Only nuclear labeling was scored, and antibody dilution of 1:2000 was used. In normal tissues, only rare cells in seminiferous tubules were labeled; all other organs were negative. All chordomas (75/76), except a sarcomatous one, were positive, whereas chondrosarcomas were negative. Among epithelial tumors, positivity was often detected in embryonal carcinoma (74%) and seminoma (45%). Pulmonary small cell carcinoma was often positive (41%), whereas pulmonary and pancreatic adenocarcinomas only rarely showed nuclear brachyury positivity (3% to 4%). Common carcinomas such as ductal carcinomas of the breast or adenocarcinomas of the prostate only exceptionally showed nuclear positivity (<1%). No colorectal, hepatocellular, renal cell, squamous cell, thyroid or urothelial carcinoma, or mesothelioma showed nuclear brachyury positivity. Among mesenchymal and neuroectodermal tumors, only isolated cases of melanoma, malignant peripheral nerve sheath tumor, rhabdomyosarcoma, synovial sarcoma, and follicular lymphoma showed nuclear expression. However, as shown previously with lung carcinoma, experiments with lower antibody dilutions (1:200 to 1:500) showed weak cytoplasmic and nuclear labeling in breast cancers. In addition to chordoma, we show here for the first time that nuclear brachyury expression is prevalent in embryonal carcinoma, seminoma, and small cell carcinoma of the lung but very rare in common carcinomas, sarcomas, and melanoma. With these reservations, we have demonstrated the presence of nuclear brachyury immunoreactivity to be a sensitive and fairly specific marker for chordoma.
Brachyury是一种T-box家族转录因子，通常在脊索和脊索瘤中表达。一些研究认为Brachyury对脊索瘤有高度特异性，而其他采用RT-PCR和免疫组化方法的研究认为Brachyury在多种常见的癌中可表达，并参与上皮-间质转化和转移过程。本研究中，我们应用免疫组化方法检测了5229例不同肿瘤Brachyury的核表达情况，并使用了一种新的兔单克隆抗体和自动免疫组化仪（Leca Bond Max）。我们只记录核的着色，使用的一抗稀释度为1:2000。正常组织中，只有曲细精管中少许细胞着色；其他所有器官均为阴性。所有的脊索瘤（75/76），除1例肉瘤型外，均为阳性，而软骨肉瘤为阴性。上皮性肿瘤中，胚胎性癌（74%）和精原细胞瘤（45%）常常阳性。肺小细胞癌常阳性（41%），而肺和胰腺腺癌Brachyury核阳性少见（3%-4%）。常见的癌如乳腺癌或前列腺癌偶见核阳性（＜1%）。结肠癌、肝细胞肝癌、肾细胞癌、鳞状细胞癌、甲状腺癌或尿路上皮癌、间皮瘤均无Brachyury核阳性。间叶和神经外胚层肿瘤中，只有黑色素瘤、恶性周围神经鞘膜瘤、横纹肌肉瘤、滑膜肉瘤和滤泡性淋巴瘤显示散在核阳性。然而，正如先前肺癌研究显示，实验中使用较低稀释度（1:200-1:500）可以在乳腺癌中呈弱的细胞浆和细胞核着色。除脊索瘤外，我们在此首次报道Brachyury核阳性普遍见于胚胎性癌、精原细胞瘤和肺小细胞癌，但在常见的癌、肉瘤和黑色素瘤中非常罕见。我们证实了Brachyury细胞核的免疫阳性是脊索瘤一个敏感和相对特异的标记。