Mahooti Sepi, Porter Kyle, Alpaugh Mary L, Ye Yin, Xiao Yi, Jones Susie, Tellez Joseph D, Barsky Sanford H
Department of Pathology and Center for Biostatistics, The Ohio State University College of Medicine, Columbus, Ohio 43210.
Center for Biostatistics, The Ohio State University College of Medicine, Columbus, Ohio 43210.
Oncotarget. 2010 Jun;1(2):131-147. doi: 10.18632/oncotarget.117.
The canonical view of the origin of tumor lymphovascular emboli is that they usually originate from lymphovascular invasion as part of a multistep metastatic process. Recent experimental evidence has suggested that metastasis can occur earlier than previously thought and we found evidence that tumor emboli formation can result from the short-circuiting step of encircling lymphovasculogenesis. Experimentally, we used a xenograft of human inflammatory breast cancer (MARY-X), a model that exhibited florid tumor emboli, to generate tumoral spheroids in vitro. In observational studies, we chose human breast carcinoma cases where there appeared to be a possible transition of in situ carcinoma to lymphovascular emboli without intervening stromal invasion. These cases were studied by morphometry as well as IHC with tumor proliferation (Ki-67) and adhesion (E-cadherin) markers, myoepithelial (p63), as well as endothelial (podoplanin [D2-40], CD31, VEGFR-3, Prox-1) markers. Unlabelled spheroids coinjected with either GFP or RFP-human myoepithelial cells or murine embryonal fibroblasts (MEFs) gave rise to tumors which exhibited GFP/RFP immunoreactivity within the cells lining the emboli-containing lymphovascular channels. In vitro studies demonstrated that the tumoral spheroids induced endothelial differentiation of cocultured myoepithelial cells and MEFs, measured by real time PCR and immunofluorescence. In humans, the in situ clusters exhibited similar proliferation, E-cadherin immunoreactivity and size as the tumor emboli (p =.5), suggesting the possibility that the latter originated from the former. The in situclusters exhibited a loss (50%-100%) of p63 myoepithelial immunoreactivity but not E-cadherin epithelial immunoreactivity. The tumor emboli were mainly present within lymphatic channels whose dual p63/CD31, p63/D2-40 and p63/VEGFR-3 and overall weak patterns of D2-40/CD31/VEGFR-3 immunoreactivities suggested that they represented immature and newly created vasculature derived from originally myoepithelial-lined ducts. Collectively both experimental as well as observational studies suggested the possibility that these breast cancer emboli resulted from encircling lymphovasculogenesis rather than conventional lymphovascular invasion.
肿瘤淋巴管栓子起源的传统观点认为，它们通常起源于淋巴管侵犯，是多步骤转移过程的一部分。最近的实验证据表明，转移可能比之前认为的更早发生，并且我们发现有证据显示肿瘤栓子的形成可能源于围绕淋巴管生成的短路步骤。在实验中，我们使用了人炎性乳腺癌异种移植模型（MARY-X），该模型呈现出大量肿瘤栓子，以在体外生成肿瘤球体。在观察性研究中，我们选择了一些人类乳腺癌病例，这些病例中似乎存在原位癌向淋巴管栓子的可能转变，而没有中间的间质浸润。通过形态计量学以及使用肿瘤增殖（Ki-67）和黏附（E-钙黏蛋白）标记物、肌上皮（p63）以及内皮（足板蛋白[D2-40]、CD31、VEGFR-3、Prox-1）标记物的免疫组化对这些病例进行了研究。与绿色荧光蛋白（GFP）或红色荧光蛋白（RFP）标记的人肌上皮细胞或小鼠胚胎成纤维细胞（MEF）共注射的未标记球体产生了肿瘤，这些肿瘤在含有栓子的淋巴管通道内衬细胞内呈现出GFP/RFP免疫反应性。体外研究表明，通过实时聚合酶链反应（PCR）和免疫荧光检测，肿瘤球体诱导了共培养的肌上皮细胞和MEF的内皮分化。在人类中，原位细胞簇与肿瘤栓子表现出相似的增殖、E-钙黏蛋白免疫反应性和大小（p = 0.5），这表明后者可能起源于前者。原位细胞簇呈现出p63肌上皮免疫反应性的丧失（50%-100%），但E-钙黏蛋白上皮免疫反应性未丧失。肿瘤栓子主要存在于淋巴管内，其p63/CD31、p63/D2-40和p63/VEGFR-3的双重表达以及D2-40/CD31/VEGFR-3免疫反应性的整体较弱模式表明，它们代表了源自最初由肌上皮衬里的导管的未成熟和新生成的脉管系统。总体而言，实验研究和观察性研究均表明，这些乳腺癌栓子可能源于围绕淋巴管生成，而非传统的淋巴管侵犯。
