This case-control study explored compositions of gut microbiome in recurrent malignant gliomas patients who had received bevacizumab and Temozolomide combination treatment and Temozolomide monotherapy. We investigated gut microbiota communities in feces of 29 recurrent malignant gliomas patients received combination treatment with bevacizumab and Temozolomide (Group 1) and monotherapy with Temozolomide alone (Group 2). We took advantage of the high-throughput Illumina Miseq sequencing technology by targeting the third and fourth hypervariable (V3–V4) regions of the 16S ribosomal RNA (rRNA) gene. We found that the structures and richness of the fecal microbiota in Group 1 were different from Group 2 with LEfSe analysis. The fecal microbiota in both Group 1 and Group 2 were mainly composed by Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria. However, Group 1 patients had higher relative abundance of Firmicutes, Bacteroidetes, Actinobacteria and lower relative abundance of Bacteroidetes and Cyanobacteria in their fecal microbiota than that in Group 2 patients. To evaluate bevacizumab involved post-treatment state of the fecal microbiota profile, we used random forest predictive model and ensembled decision trees with an AUC of 0.54. This study confirmed that the gut microbiota was different in recurrent malignant gliomas patients received the combination therapy of bevacizumab and Temozolomide compared with Temozolomide monotherapy. Our discover can help better understand the influence of bevacizumab related treatment on recurrent malignant gliomas patients. Therefore, this finding may also support the potentially therapeutic options for recurrent malignant gliomas patients such as fecal microbiota transplant.

这项病例对照研究探讨了接受贝伐珠单抗和替莫唑胺联合治疗以及替莫唑胺单药治疗的复发性恶性胶质瘤患者的肠道微生物组组成。我们调查了 29 名接受贝伐珠单抗和替莫唑胺联合治疗（第 1 组）和单独替莫唑胺单药治疗（第 2 组）的复发性恶性胶质瘤患者粪便中的肠道微生物群落。我们利用高通量 Illumina Miseq 测序技术，靶向 16S 核糖体 RNA (rRNA) 基因的第三和第四高变区 (V3–V4)。通过 LEfSe 分析，我们发现第 1 组粪便微生物群的结构和丰富度与第 2 组不同。第 1 组和第 2 组的粪便微生物群主要由厚壁菌门、变形菌门、拟杆菌门和放线菌门。然而，第 1 组患者的厚壁菌门、拟杆菌门、放线菌门的相对丰度较高，而拟杆菌门和蓝藻门的相对丰度较低在他们的粪便微生物群中比在第 2 组患者中。为了评估贝伐珠单抗治疗后粪便微生物群概况的状态，我们使用了随机森林预测模型和 AUC 为 0.54 的集成决策树。该研究证实，与替莫唑胺单药治疗相比，接受贝伐珠单抗和替莫唑胺联合治疗的复发性恶性胶质瘤患者的肠道微生物群存在差异。我们的发现有助于更好地了解贝伐珠单抗相关治疗对复发性恶性胶质瘤患者的影响。因此，这一发现也可能支持复发性恶性胶质瘤患者的潜在治疗选择，例如粪便微生物群移植。