Characterization of microbial and host requirements for colonic biofilm assembly and biofilm-mediated colon tumorigenesis

散发性结直肠癌(CRC)仍然是全球的健康负担，是癌症的主要原因之一。 和癌症相关的死亡，引人注目的是，在中国的年轻患者中也出现了严重的健康危机 美国年龄在50岁以下。这些数据表明，识别变化的贡献者的新努力 儿童权利公约的景观是迫切需要的。在这份R00提案中，我们试图剖析大会和 侵袭性、多菌结肠生物膜背后的致瘤机制 在西尔斯实验室建立，几乎是肝脏近端结直肠癌的普遍特征 柔韧。在没有结直肠癌的健康患者的亚组(10%-15%)上也发现了生物膜，其中 生物膜与早期的癌前改变有关，表明细菌生物膜在结直肠癌中的作用。 发展。这些生物膜也与多胺代谢物的大量升高有关。 光谱分析和诱导小鼠产生强烈的IL-17反应 周，一种细胞因子标志与人类结直肠癌预后较差有关。由以下物质制成的组织浆液 人类生物膜在小鼠结肠远端重新组装成生物膜；这些浆液中的一些--但不是全部-- 在无菌ApcMin/+小鼠体内直接致瘤10-15周。一种广泛的培养 在小鼠体内接种致瘤泥浆后，发现35个细菌分离株，当再次接种时 到另外的小鼠，重述了肿瘤发生的原始患者的肿瘤浆液。我们的具体目标 寻求在这些初步研究的基础上再接再厉。特定目标(SA)1将确定关键细菌种类 在导致生物被膜形成和肿瘤形成的35种分离混合物中。SA2将测试 假设IL-17和其他免疫参数是生物被膜形成和 结合单细胞RNA测序、流式细胞术和生物膜介导的肿瘤发生 QRT-PCR法。用IL-17抗体或基因敲除小鼠进行治疗调节将被用来证实 IL-17在生物膜形成和生物膜介导的肿瘤发生中的需求。SA3将利用高级 测定患者和小鼠生物膜相关代谢物的质谱学方法 组织和这些代谢物在选定样本中的定位。这项提案中的实验将 提供有关生物膜形成的宿主和微生物需求的有价值的信息 生物膜介导的肿瘤发生，可能导致生物膜潜在的治疗靶点或生物标记物。

Sporadic colorectal cancer (CRC) remains a global health burden as one of the leading causes of cancer and cancer-related deaths, and, strikingly, is also emerging as an acute health crisis in younger patients in the US under the age of 50. These data suggest that novel efforts to identify contributors to the changing landscape of CRC are urgently needed. In this R00 proposal, we seek to dissect the assembly and tumorigenic mechanisms behind invasive, polymicrobial colonic biofilms, which were previously established in the Sears laboratory to be a nearly universal feature of CRC tumors proximal to the hepatic flexure. Biofilms were also identified on a subset (10-15%) of healthy patients without CRC, in whom biofilms were associated with early, procarcinogenic changes, positing a role for bacterial biofilms in CRC development. These biofilms were also associated with elevations in polyamine metabolites in mass spectrometry-based analyses and induced a strong Interleukin-17 (IL-17) response in the mice by one week, a cytokine signature associated with a worse prognosis in human CRC. Tissue slurries made from human biofilms re-assembled into biofilms in the distal mouse colon; some - but not all – of these slurries were directly tumorigenic in germ-free ApcMin/+ mice by 10-15 weeks. Extensive culturing of one tumorigenic slurry following inoculation into mice revealed 35 bacterial isolates that, when re-inoculated into additional mice, recapitulated the tumorigenesis of the original patient tumor slurry. Our specific aims seek to build on these preliminary studies. Specific Aim (SA) 1 will identify the critical bacterial species within the 35 isolate mixture that are responsible for biofilm formation and tumorigenesis. SA2 will test the hypothesis that IL-17 and other immune parameters are critical mediators of biofilm formation and biofilm-mediated tumorigenesis utilizing a combination of single-cell RNA sequencing, flow cytometry, and qRT-PCR. Therapeutic modulation with an IL-17 antibody or knockout mice will be used to confirm the requirement of IL-17 in biofilm formation and biofilm-mediated tumorigenesis. SA3 will utilize advanced mass spectrometry methods to determine metabolites associated with biofilms in both patient and mouse tissues and the localization of these metabolites in select samples. The experiments in this proposal will provide valuable information regarding the host and microbial requirements for biofilm formation and biofilm-mediated tumorigenesis that may lead to potential therapeutic targets or biomarkers for biofilms.