Antibiotics treatment ameliorates TET2 loss-of-function associated hematological malignancies

TET2 is one of the most frequently mutated genes in hematological malignancies. TET2 mutations are also frequently observed in healthy individuals with clonal hematopoiesis. Additional factors, such as inflammatory stress, might promote the expansion and initiate the pre-leukemic condition of Tet2 deficient hematopoietic stem cells. Antibiotics treatment is frequently used in normal individuals and patients with hematological malignancies treatment to suppress infection-induced inflammation. However, prolonged antibiotics treatment resulted in bone marrow suppression and gut microbiota alteration. In our study, we observed that the expansion of Tet2 deficient myeloid cells are positively correlated with serum cytokine levels at pre-malignant stages. We then evaluated the effect of antibiotic treatment in Tet2 deficient myeloid and lymphoid tumors in vivo. We found that antibiotics treatment suppressed the growth of Tet2 deficient malignant cells in vivo. RNA-seq analysis revealed significant changes in immune related signaling pathways (e.g., Tnf-a signaling) in antibiotics treated Tet2 deficient myeloid and lymphoid tumor cells. Suppression of Tnf-a signaling using pharmacological inhibitors partially suppressed Tet2 deficient tumor cell growth in vivo. In summary, our results suggest that the expansion of Tet2 deficient blood cells are positively associated with a pre-inflammatory condition and suppression of inflammatory pathways may attenuate the progression of TET2 inactivation-associated hematological malignancies. Overall design: Normal Tet2KO CD4+ T cells and lymphoma cells were isolated from Tet2 deficient mouse model to identify the differential expressed genes. Tet2KO lymphoma mouse and CMML mouse were treated with and without antibiotics cocktail (ABX). Cells were isolated from these groups to identify the differential expressed genes between ABX treated and untreated groups. Third-party re-analysis: LK1 (GSM1902319) and LK2 (GSM1902320) processed data are represented in LK_KO-Tet2KO_CMML_vehicle-Tet2KO_CD4_Tcell-Tet2KO_lymphoma.normalized.txt.

TET2基因是血液系统恶性肿瘤中最常发生突变的基因之一。TET2突变在存在克隆性造血的健康个体中也较为常见。诸如炎症应激等其他因素，可促进TET2缺陷型造血干细胞的扩增，并启动其白血病前期病变状态。抗生素治疗常被应用于健康个体及血液系统恶性肿瘤患者，以抑制感染诱导的炎症反应。但长期抗生素治疗可引发骨髓抑制与肠道菌群失调。本研究中，我们观察到在恶性前期阶段，TET2缺陷型髓系细胞的扩增与血清细胞因子水平呈正相关。随后我们在体内评估了抗生素治疗对TET2缺陷型髓系及淋巴系肿瘤的作用效果。结果显示，抗生素治疗可在体内抑制TET2缺陷型恶性细胞的增殖。RNA测序（RNA-seq）分析显示，经抗生素处理的TET2缺陷型髓系及淋巴系肿瘤细胞中，免疫相关信号通路（如Tnf-a信号通路）发生了显著改变。使用药理学抑制剂抑制Tnf-a信号通路，可在体内部分抑制TET2缺陷型肿瘤细胞的增殖。综上，本研究结果表明，TET2缺陷型血细胞的扩增与前期炎症状态呈正相关；抑制炎症通路或可延缓TET2失活相关血液系统恶性肿瘤的进展。实验设计：本研究从TET2缺陷型小鼠模型中分离正常TET2敲除（Tet2KO）CD4+ T细胞及淋巴瘤细胞，以筛选差异表达基因。TET2敲除淋巴瘤小鼠与慢性粒单核细胞白血病（CMML）小鼠分别接受抗生素联合制剂（ABX）处理或空白对照处理。从各组小鼠中分离细胞，以筛选抗生素处理组与未处理组之间的差异表达基因。第三方再分析：LK1（GSM1902319）与LK2（GSM1902320）的处理后数据已收录于LK_KO-Tet2KO_CMML_vehicle-Tet2KO_CD4_Tcell-Tet2KO_lymphoma.normalized.txt文件中。