Division of Hematology/Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America.
PLoS One. 2012;7(6):e38589. doi: 10.1371/journal.pone.0038589. Epub 2012 Jun 15.
TSC2-deficient cells can proliferate in the lungs, kidneys, and other organs causing devastating progressive multisystem disorders such as lymphangioleiomyomatosis (LAM) and tuberous sclerosis complex (TSC). Preclinical models utilizing LAM patient-derived cells have been difficult to establish. We developed a novel animal model system to study the molecular mechanisms of TSC/LAM pathogenesis and tumorigenesis and provide a platform for drug testing.
TSC2-deficient human cells, derived from the angiomyolipoma of a LAM patient, were engineered to co-express both sodium-iodide symporter (NIS) and green fluorescent protein (GFP). Cells were inoculated intraparenchymally, intravenously, or intratracheally into athymic NCr nu/nu mice and cells were tracked and quantified using single photon emission computed tomography (SPECT) and computed tomography (CT). Surprisingly, TSC2-deficient cells administered intratracheally resulted in rapid dissemination to lymph node basins throughout the body, and histopathological changes in the lung consistent with LAM. Estrogen was found to be permissive for tumor growth and dissemination. Rapamycin inhibited tumor growth, but tumors regrew after the drug treatment was withdrawn.
We generated homogeneous NIS/GFP co-expressing TSC2-deficient, patient-derived cells that can proliferate and migrate in vivo after intratracheal instillation. Although the animal model we describe has some limitations, we demonstrate that systemic tumors formed from TSC2-deficient cells can be monitored and quantified noninvasively over time using SPECT/CT, thus providing a much needed model system for in vivo drug testing and mechanistic studies of TSC2-deficient cells and their related clinical syndromes.
TSC2 缺陷细胞可在肺部、肾脏和其他器官中增殖，导致破坏性的进行性多系统疾病，如淋巴管肌瘤病（LAM）和结节性硬化症复合征（TSC）。利用 LAM 患者来源细胞建立的临床前模型一直难以建立。我们开发了一种新的动物模型系统，以研究 TSC/LAM 发病机制和肿瘤发生的分子机制，并为药物测试提供一个平台。
从 LAM 患者的血管平滑肌脂肪瘤中获得的 TSC2 缺陷人细胞被工程改造为共表达钠碘转运体（NIS）和绿色荧光蛋白（GFP）。细胞通过实质内、静脉内或气管内接种到无胸腺 NCr nu/nu 小鼠体内，并使用单光子发射计算机断层扫描（SPECT）和计算机断层扫描（CT）进行跟踪和定量。令人惊讶的是，气管内给予 TSC2 缺陷细胞导致快速扩散到全身淋巴结盆地，并导致肺部出现符合 LAM 的组织病理学变化。雌激素被发现对肿瘤生长和扩散是允许的。雷帕霉素抑制肿瘤生长，但停药后肿瘤会重新生长。
我们生成了均匀的 NIS/GFP 共表达 TSC2 缺陷的、源自患者的细胞，这些细胞在气管内滴注后可在体内增殖和迁移。尽管我们描述的动物模型存在一些局限性，但我们证明，源自 TSC2 缺陷细胞的全身肿瘤可以使用 SPECT/CT 进行非侵入性监测和定量，从而为体内药物测试和 TSC2 缺陷细胞及其相关临床综合征的机制研究提供了急需的模型系统。
