用于分析基因工程小鼠模型中原位ATC肿瘤的高分辨率超声检查
Summary
本协议描述了用于可视化整个小鼠甲状腺和监测间变性甲状腺癌生长的高频超声检查。
Abstract
间变性甲状腺癌（ATC）与预后不良和中位生存时间短有关，但没有有效的治疗方法可显著改善结局。模仿ATC进展的基因工程小鼠模型可能有助于研究人员研究这种疾病的治疗方法。杂交三种不同基因型的小鼠， TPO-cre / ERT2;布拉夫CA/wt;建立了Trp53 Δex2-10/Δex2-10转基因ATC模型。腹腔注射他莫昔芬，过表达BrafV600E ，Trp53缺失诱导ATC小鼠模型，约1个月内产生肿瘤。应用高分辨率超声研究肿瘤的发生和发展，通过测量肿瘤大小获得动态生长曲线。与磁共振成像（MRI）和计算机断层扫描相比，超声在观察ATC鼠模型方面具有无创，便携，实时和无辐射暴露的优势。高分辨率超声适用于动态和多重测量。然而，小鼠甲状腺的超声检查需要相关的解剖学知识和经验。本文提供了利用高分辨率超声扫描转基因ATC模型中肿瘤的详细程序。同时，列出了超声参数调整、超声扫描技巧、动物的麻醉和恢复以及其他过程中需要注意的要素。
Introduction
虽然间变性甲状腺癌（ATC）占甲状腺癌的不到2%，但它每年导致超过50%的甲状腺癌相关死亡。诊断为 ATC 后的中位生存时间仅为约 6 个月，并且没有可显著提高生存率的治疗方法1，2。
ATC的罕见性阻碍了研究疾病如何开始和积极进展的研究。最近出现了模仿该疾病的基因工程小鼠模型，这些模型提供了对该疾病及其对可能治疗方法的反应的见解3，4，5。此类研究需要精确的肿瘤成像进行测量和监测，这通常使用磁共振成像、计算机断层扫描或高分辨率超声检查进行6，7。超声检查已广泛用于小鼠器官。它比磁共振成像和计算机断层扫描具有优势，因为它可以实时进行并且不会使受试者暴露于辐射中，并且必要的设备足够小，可以携带8，9。然而，使用超声连续监测ATC生长的研究很少;因此，这项工作探讨了超声在这种情况下的效用。
在这里，提出了一种使用高分辨率超声检查在ATC小鼠模型中准确扫描，监测和测量肿瘤的方案。
Protocol
Representative Results
Discussion
该协议使用高分辨率超声检查来分析基因工程小鼠模型中的原位ATC肿瘤。转基因模型，基因型为 TPO-cre/ERT2; 布拉夫CA/wt;Trp53 Δex2-10/Δex2-10，由我们的实验室开发。动物过度表达BrafV600E 而缺乏Trp53;腹膜内注射他莫昔芬导致肿瘤生长约1个月10。肿瘤生长迅速，并在50天内达到可测量的大小。该方案用于监测肿瘤生长4个月。
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Divulgations
The authors have nothing to disclose.
Acknowledgements
这项研究没有获得公共、商业或非营利资助机构的具体资助。
Materials
| Adhesive tape | Winner | ||
| Anesthesia system | RWDlifescience | ||
| Brafflox/wt mice | Collaboration with Institute of Life Science, eBond Pharmaceutical Technology Ltd, Chengdu, China | ||
| Chamber for anesthesia induction | RWDlifescience | ||
| Cotton swabs | Winner | ||
| Depilatory cream | Veet | ||
| Electric heating blanket | Petbee | ||
| Isoflurane vaporizer | RWDlifescience | ||
| Medical gloves | Winner | ||
| Paper towels | Breeze | B914JY | |
| TPO-cre/ERT2 mice | Collaboration with Institute of Life Science, eBond Pharmaceutical Technology Ltd, Chengdu, China | ||
| Trp53flox/wt mice | Collaboration with Institute of Life Science, eBond Pharmaceutical Technology Ltd, Chengdu, China | ||
| Ultrasound gel | Keppler | KL-250 | |
| Ultrasound machine | VisualSonics | Vevo 3100 |
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