Department of Pediatric Surgery, Children's Hospital of Fudan University, National Children's Medical Center, 399 Wanyuan Road, Shanghai 201102, China.
Department of Pediatric Surgery, Children's Hospital of Fudan University, National Children's Medical Center, 399 Wanyuan Road, Shanghai 201102, China.
J Pediatr Surg. 2021 Jul;56(7):1203-1210. doi: 10.1016/j.jpedsurg.2021.03.023. Epub 2021 Mar 26.
Kaposiform hemangioendothelioma (KHE) is a rare vascular tumor that occurs in children. Prox1 is a specific lymphatic marker for KHE. We intended to establish a Prox1 transgenic cell line resembling KHE and investigate the mechanism of sirolimus in treating KHE.
Prox1 was stably expressed in infantile hemangioma cell HemECs. RT-qPCR and Western blot were conducted to measure the expression of target genes. CCK-8, EdU assay, and cell cycle analysis were conducted to detect cell proliferation. Wound healing and transwell assay were used to evaluate cell migration and invasion.
Both mRNA and protein levels of Prox1, LYVE-1, Podoplanin were upregulated in Prox1 HemECs. An acceleration of cell growth and a rise in migration and invasion were observed with Prox1 overexpression. Sirolimus inhibited cell proliferation, promoted apoptosis and led to G1 phase arrest in Prox1 HemECs. The expression of p-mTOR, p-4EBP1, and p-P70S6K decreased and the ratio of LC-3 II/LC-3 I elevated after treatment of sirolimus.
Stable overexpression of Prox1 in HemECs induced a lymphatic endothelial reprogramming, and enhanced aggressive biological effects, partly resembled the invasion of KHE, and could serve as a novel model for KHE. Sirolimus may block mTOR-mediated pathways and induced autophagy in KHE.
卡波西样血管内皮细胞瘤（KHE）是一种罕见的儿童血管肿瘤，Prox1 是 KHE 的特异性淋巴管标志物。本研究旨在建立类似于 KHE 的 Prox1 转基因细胞系，并探讨西罗莫司治疗 KHE 的机制。
Prox1 在婴儿血管瘤细胞 HemECs 中稳定表达。采用 RT-qPCR 和 Western blot 检测靶基因的表达。CCK-8、EdU 检测和细胞周期分析检测细胞增殖。划痕愈合和 Transwell 检测用于评估细胞迁移和侵袭。
Prox1 HemECs 中 Prox1、LYVE-1、Podoplanin 的 mRNA 和蛋白水平均上调。Prox1 过表达可加速细胞生长，促进迁移和侵袭。西罗莫司抑制 Prox1 HemECs 的增殖，促进细胞凋亡，并导致 G1 期阻滞。西罗莫司处理后，p-mTOR、p-4EBP1 和 p-P70S6K 的表达减少，LC-3 II/LC-3 I 的比值升高。
HemECs 中 Prox1 的稳定过表达诱导淋巴管内皮重编程，并增强侵袭性生物学效应，部分类似于 KHE 的侵袭，可作为 KHE 的新型模型。西罗莫司可能通过阻断 mTOR 介导的通路并诱导 KHE 中的自噬来发挥作用。
