Center for Cardiovascular Regeneration, Department of Cardiovascular Sciences, Houston Methodist Research Institute, TX.
Circulation. 2018 Aug 28;138(9):913-928. doi: 10.1161/CIRCULATIONAHA.118.033939.
Angiogenesis is integral for embryogenesis, and targeting angiogenesis improves the outcome of many pathological conditions in patients. TBX20 is a crucial transcription factor for embryonic development, and its deficiency is associated with congenital heart disease. However, the role of TBX20 in angiogenesis has not been described.
Loss- and gain-of-function approaches were used to explore the role of TBX20 in angiogenesis both in vitro and in vivo. Angiogenesis gene array was used to identify key downstream targets of TBX20.
Unbiased gene array survey showed that TBX20 knockdown profoundly reduced angiogenesis-associated PROK2 (prokineticin 2) gene expression. Indeed, loss of TBX20 hindered endothelial cell migration and in vitro angiogenesis. In a murine angiogenesis model using subcutaneously implanted Matrigel plugs, we observed that TBX20 deficiency markedly reduced PROK2 expression and restricted intraplug angiogenesis. Furthermore, recombinant PROK2 administration enhanced angiogenesis and blood flow recovery in murine hind-limb ischemia. In zebrafish, transient knockdown of tbx20 by morpholino antisense oligos or genetic disruption of tbx20 by CRISPR/Cas9 impaired angiogenesis. Furthermore, loss of prok2 or its cognate receptor prokr1a also limited angiogenesis. In contrast, overexpression of prok2 or prokr1a rescued the impaired angiogenesis in tbx20-deficient animals.
Our study identifies TBX20 as a novel transcription factor regulating angiogenesis through the PROK2-PROKR1 (prokineticin receptor 1) pathway in both development and disease and reveals a novel mode of angiogenic regulation whereby the TBX20-PROK2-PROKR1 signaling cascade may act as a "biological capacitor" to relay and sustain the proangiogenic effect of vascular endothelial growth factor. This pathway may be a therapeutic target in the treatment of diseases with dysregulated angiogenesis.
血管生成对于胚胎发生至关重要，靶向血管生成可改善患者许多病理状况的预后。TBX20 是胚胎发育的关键转录因子，其缺失与先天性心脏病有关。然而，TBX20 在血管生成中的作用尚未描述。
采用缺失和获得功能的方法，在体外和体内研究 TBX20 在血管生成中的作用。采用血管生成基因芯片鉴定 TBX20 的关键下游靶基因。
无偏基因芯片调查显示，TBX20 敲低显著降低了与血管生成相关的 PROK2（促血管生成素 2）基因表达。事实上，TBX20 的缺失会阻碍内皮细胞迁移和体外血管生成。在使用皮下植入的 Matrigel 塞的小鼠血管生成模型中，我们观察到 TBX20 缺乏显著降低 PROK2 表达并限制塞内血管生成。此外，重组 PROK2 给药可增强小鼠后肢缺血模型中的血管生成和血流恢复。在斑马鱼中，通过 morpholino 反义寡核苷酸或 CRISPR/Cas9 对 tbx20 进行基因敲除，瞬态敲低 tbx20，会损害血管生成。此外，prok2 或其同源受体 prokr1a 的缺失也限制了血管生成。相比之下，prok2 或 prokr1a 的过表达可挽救 tbx20 缺陷动物中的受损血管生成。
本研究确定 TBX20 是一种新型转录因子，通过 PROK2-PROKR1（促血管生成素受体 1）途径调节发育和疾病中的血管生成，并揭示了一种新的血管生成调节模式，其中 TBX20-PROK2-PROKR1 信号级联可能作为“生物电容器”，传递和维持血管内皮生长因子的促血管生成效应。该途径可能是治疗血管生成失调疾病的靶点。
