Antibiotic-induced microbial imbalance, or dysbiosis, has systemic and long-lasting effects on the host and response to cancer therapies. However, the effects on tumor endothelial cells are largely unknown. Therefore, the goal of the current study was to generate matched B16-F10 melanoma associated endothelial cell lines isolated from mice with and without antibiotic-induced dysbiosis. After validating endothelial cell markers on a genomic and proteomic level, functional angiogenesis assays (i.e., migration and tube formation) also confirmed their vasculature origin. Subsequently, we found that tumor endothelial cells derived from dysbiotic mice (TEC-Dys) were more sensitive to ionizing radiotherapy in the range of clinically-relevant hypofractionated doses, as compared to tumor endothelial cells derived from orthobiotic mice (TEC-Ortho). In order to identify tumor vasculature-associated drug targets during dysbiosis, we used tandem mass tag mass spectroscopy and focused on the statistically significant cellular membrane proteins overexpressed in TEC-Dys. By these criteria c-Met was the most differentially expressed protein, which was validated histologically by comparing tumors with or without dysbiosis. Moreover, in vitro, c-Met inhibitors Foretinib, Crizotinib and Cabozantinib were significantly more effective against TEC-Dys than TEC-Ortho. In vivo, Foretinib inhibited tumor growth to a greater extent during dysbiosis as compared to orthobiotic conditions. Thus, we surmise that tumor response in dysbiotic patients may be greatly improved by targeting dysbiosis-induced pathways, such as c-Met, distinct from the many targets suppressed due to dysbiosis.

抗生素引起的微生物失衡或生态失调对宿主和对癌症治疗的反应具有系统性和持久的影响。然而，对肿瘤内皮细胞的影响在很大程度上是未知的。因此，当前研究的目标是生成匹配的 B16-F10 黑色素瘤相关内皮细胞系，这些内皮细胞系是从有和没有抗生素引起的生态失调的小鼠中分离出来的。在基因组和蛋白质组水平上验证内皮细胞标记后，功能性血管生成测定（即迁移和管形成）也证实了它们的脉管系统起源。随后，我们发现与来自正生小鼠的肿瘤内皮细胞 (TEC-Ortho) 相比，来自失调小鼠 (TEC-Dys) 的肿瘤内皮细胞对临床相关大分割剂量范围内的电离放射疗法更敏感。为了在生态失调期间识别肿瘤脉管系统相关的药物靶点，我们使用串联质量标签质谱法并专注于 TEC-Dys 中过表达的具有统计学意义的细胞膜蛋白。根据这些标准，c-Met 是表达差异最大的蛋白质，通过比较有或没有生态失调的肿瘤在组织学上得到验证。此外，在体外，c-Met 抑制剂 Foretinib、Crizotinib 和 Cabozantinib 对 TEC-Dys 的疗效显着高于 TEC-Ortho。在体内，与正生条件相比，Foretinib 在生态失调期间更大程度地抑制肿瘤生长。因此，我们推测，通过靶向菌群失调诱导的通路（例如 c-Met）可能会大大改善菌群失调患者的肿瘤反应，这与许多因菌群失调而被抑制的靶点不同。