转移是癌症相关死亡的主要原因，针对血管生成的治疗策略成为治疗黑色素瘤转移的疗法。发现具有特异作用机制的新型抗血管生成化合物仍然是我们的目标。在本研究中，通过生物活性引导，我们发现了海洋源真菌Aspergillus clavutus LZD32-24的乙酸乙酯提取物在Tg (fli1a: EGFP) 斑马鱼模型中具有显著的抗血管生成活性。通过广泛的色谱分离，我们分离得到了48个吲哚喹唑啉类生物碱，其中包括21个新的类似物，命名为clavutoines A-U (1-21)。通过光谱数据（包括ECD、单晶X射线衍射和量子化学计算）确定了它们的结构，并进行了构型确定。在这些活性类似物中，喹哚啉B（QB）在斑马鱼胚胎中抑制血管生长方面表现出最佳功效。QB显著抑制了人脐静脉内皮细胞（HUVECs）的迁移、侵袭和管腔形成，并且具有较弱的细胞毒性。研究发现QB通过抑制ROCK/MYPT1/MLC2/coffin和FAK/Src信号通路，然后干扰肌动蛋白细胞骨架的结构，从而发挥作用。此外，QB减少了离体鸡胚绒毛膜（CAM）中新血管的数量，并通过抑制血管生成来抑制C57BL/6小鼠肺中B16F10黑色素瘤细胞的转移。这些发现表明QB是一种潜在的新型抗血管生成剂，可用于抑制黑色素瘤的转移。版权所有©2023 Elsevier Inc.。保留所有权利。

Metastasis is the leading cause of cancer-related mortality, targeting angiogenesis emerges as a therapeutic strategy for the treatment of melanoma metastasis. Discovery of new antiangiogenic compounds with specific mechanism of action is still desired. In present study, a bioassay-guidance uncovers the EtOAc extract of a marine-derived fungus Aspergillus clavutus LZD32-24 with significant inhibitory activity against the angiogenesis in Tg (fli1a: EGFP) zebrafish model. Extensive chromatographic fractionation led to the isolation of 48 indoloquinazoline alkaloids, including 21 new analogues namely clavutoines A-U (1-21). Their structures were determined by the spectroscopic data, including the ECD, single crystal X-ray diffraction and quantum chemical calculation for the configurational assignments. Among the bioactive analogues, quinadoline B (QB) showed the most efficacy to suppress the zebrafish vascular outgrowth in zebrafish embryos. QB markedly inhibited the migration, invasion and tube formation with weak cytotoxicity in human umbilical vein endothelial cells (HUVECs). Investigation of the mode of action revealed QB suppressed the ROCK/MYPT1/MLC2/coffin and FAK /Src signaling pathways, and subsequently disrupted actin cytoskeletal organization. In addition, QB reduced the number of new vessels sprouting from the ex vivo chick chorioallantoic membrane (CAM), and inhibited the metastasis of B16F10 melanoma cells in lung of C57BL/6 mice through suppressing angiogenesis. These findings suggest that QB is a potential lead for the development of new antiangiogenic agent to inhibit melanoma metastasis.Copyright © 2023 Elsevier Inc. All rights reserved.