The difference between left- and right-sided colon cancer has become the focus of global attention, and researchers have found differences in the morbidity, molecular biological characteristics, and response to targeted drug therapy between left- and right-sided colon cancer. Therefore, the identification of more effective predictive indicators is critical for providing guidance to future clinical work. We collected samples from different colon sites and regions and analyzed the identities and distributions of differentially expressed species in the microbiota in the left and right sides of the colon to better explore the pathogenesis of colon cancer and provided a basis for individualized drug therapy. We collected samples from different regions in the body of 40 patients with colon cancer, including stool and tissues. The Subjects were classified into four groups, and this classification was mainly based on the colon cancer distribution. The microbiota composition of the left-sided and right-sided colon samples was assessed by specifically amplifying the V3-V4 region of the 16S rDNA gene from DNA extracts from the samples. These amplicons were examined by Illumina HiSeq 2500 sequencing. The microbial taxa in the left-sided colon samples are more abundant than those in the right-sided colon samples. The flora in the left-sided colon samples, such as Clostridium perfringens and Fusobacterium nucleatum, might be associated with VEGF expression and are more likely to promote colon cancer. The microbiota distribution in the right-sided colon samples is less invasive and harmful and particularly rich in Bifidobacterium dentium. In addition, Streptococcus, which is the target of EGFR, was found to be expressed in both the left- and right-sided colon samples but was found at a higher level in the left-sided colon samples. Additionally, the differential pathways involved in the left-sided colon samples mainly mediate DNA damage, methylation, and histone modifications, whereas those in the right-sided colon samples are dominated by DNA synthesis. The comparison of only the geographical differences revealed a significant difference in the distribution of the microbial population. The adherent microbiota composition and structural changes between the left- and right-sided colon samples might contribute to the development of colon cancer, lead to different morbidities, and further affect the prognosis of patients and their sensitivity to targeted drugs. Therefore, the identification of the differential flora in the colon could be used as an indicator for predicting the occurrence and development of colon cancer, which is also beneficial for future individualized drug therapy.

左侧和右侧结肠癌之间的差异已成为全球关注的焦点，研究人员发现左侧和右侧结肠癌的发病率，分子生物学特征以及对靶向药物治疗的反应存在差异。因此，确定更有效的预测指标对于为将来的临床工作提供指导至关重要。我们收集了来自不同结肠部位和区域的样本，并分析了结肠左右两侧菌群中差异表达物种的身份和分布，以更好地探讨结肠癌的发病机理，并为个体化药物治疗提供了基础。我们从40名结肠癌患者的身体不同区域收集了样本，包括粪便和组织。将受试者分为四组，该分类主要基于结肠癌的分布。通过从样品DNA提取物中特异性扩增16S rDNA基因的V3-V4区，可以评估左侧和右侧结肠样品的微生物群组成。通过Illumina HiSeq 2500测序检查了这些扩增子。左侧结肠样品中的微生物分类比右侧结肠样品中的丰富。左侧结肠样本中的菌群，例如 通过Illumina HiSeq 2500测序检查了这些扩增子。左侧结肠样品中的微生物分类比右侧结肠样品中的丰富。左侧结肠样本中的菌群，例如 通过Illumina HiSeq 2500测序检查了这些扩增子。左侧结肠样品中的微生物分类比右侧结肠样品中的丰富。左侧结肠样本中的菌群，例如产气荚膜梭菌 和 核梭菌可能与VEGF表达有关，并且更有可能促进结肠癌。右侧结肠样品中的微生物群分布具有较小的侵入性和有害性，尤其是富含牙双歧杆菌。此外，链球菌发现EGFR（EGFR）的靶标在左侧和右侧结肠样品中均表达，但在左侧结肠样品中水平较高。此外，左侧结肠样品中涉及的差异途径主要介导DNA损伤，甲基化和组蛋白修饰，而右侧结肠样品中的差异途径则以DNA合成为主。仅地理差异的比较揭示了微生物种群分布的显着差异。左侧和右侧结肠样品之间粘附的微生物群组成和结构变化可能有助于结肠癌的发展，导致不同的发病率，并进一步影响患者的预后及其对靶向药物的敏感性。因此，