Department of Pathology, Bács-Kiskun County Teaching Hospital, Nyíri út 38, Kecskemét, H-6000, Hungary.
Department of Pathology, University of Szeged, Állomás u. 1, Szeged, H-6725, Hungary.
Virchows Arch. 2018 Aug;473(2):145-153. doi: 10.1007/s00428-018-2343-z. Epub 2018 Mar 28.
Membranous Ki-67 staining with the MIB-1 antibody has been described in hyalinising trabecular adenomas of the thyroid and sclerosing haemangiomas of the lung. Its relatively rare occurrence in breast tumours has also been documented. The aim of the present study was to assess the rate of any membranous MIB-1 staining in breast specimens. The staining was performed at room temperature with 1:100 dilution of the antibody. One hundred four core needle biopsies and 41 operative specimens were analysed. Membranous staining was noted in 36/144 invasive carcinomas, 20/42 in situ carcinomas and 46/99 cases of peritumoural benign/normal breast epithelium. Most often, it presented as focal and partial polarised luminal membranous staining although complete circumferential staining also occurred, and membranous labelling was sometimes accompanied by cytoplasmic staining, too. In a few cases tested, greater dilution of the primary antibody did not abolish the membranous staining, which was absent with the SP6 monoclonal Ki-67 antibody. The membranous staining of invasive tumours showed no association with histological grade, lumen formation, oestrogen or progesterone receptor status or the Ki-67 nuclear labelling. In contrast, it was associated with a HER2-positive status, although it occurred in all molecular subtypes approached by immunohistochemistry. The background of this membranous staining remains elusive. It is unlikely to represent an artefact. At least partial sharing of an epitope of the nuclear Ki-67 protein with an unidentified membranous protein and some functional differences between membranous staining producing tumours and tumours lacking this pattern of staining may both contribute to some extent.
MIB-1 抗体的膜染色已在甲状腺透明小梁状腺瘤和肺硬化性血管瘤中被描述。其在乳腺肿瘤中的相对罕见发生也有记录。本研究旨在评估乳腺标本中任何膜 MIB-1 染色的发生率。染色在室温下用抗体 1:100 稀释进行。分析了 104 例核心针活检和 41 例手术标本。在 144 例浸润性癌中有 36 例、42 例原位癌中有 20 例、99 例肿瘤周围良性/正常乳腺上皮中有 46 例有膜染色。最常见的是，它呈局灶性和部分极化的腔膜染色，尽管也发生完全环形染色，并且膜标记有时伴有细胞质染色。在少数测试的情况下，减少抗体的稀释并不能消除膜染色，而 SP6 单克隆 Ki-67 抗体则没有膜染色。浸润性肿瘤的膜染色与组织学分级、腔形成、雌激素或孕激素受体状态或 Ki-67 核标记无关。相反，它与 HER2 阳性状态有关，尽管它发生在免疫组织化学所涉及的所有分子亚型中。这种膜染色的背景仍然难以捉摸。不太可能是一种人为假象。核 Ki-67 蛋白的表位与未鉴定的膜蛋白至少部分共享，以及产生膜染色的肿瘤和缺乏这种染色模式的肿瘤之间的一些功能差异，都可能在某种程度上促成这种情况。
