背景:结肠癌仍然是全球主要的健康问题,遗传因素在其发展中起着至关重要的作用。Toll样受体(TLRs)与各种癌症有关,但它们在结肠癌中的作用尚不清楚。本研究旨在鉴定TLRs启动子和3'UTR区的功能多态性,并评估其与结肠癌易感性的关系。
方法:我们进行了一项病例对照研究,涉及410名结肠癌患者和410名中国人群的健康对照。使用PCR-RFLP和TaqManMGB探针对TLR3,TLR4,TLR5和TLR7的多态性进行基因分型。使用逻辑回归分析,我们评估了TLRs多态性与结肠癌易感性的相关性.为了理解TLR4rs1927914多态性的生物学意义,我们进行了功能分析,包括荧光素酶报告基因测定和电泳迁移率变化测定(EMSA)。
结果:我们的结果表明,TLR4rs1927914多态性的G等位基因与结肠癌风险降低显着相关(OR=0.68,95CI=0.50-0.91)。分层分析表明,TLR4rs1927914AG或GG基因型有助于降低年轻人患结肠癌的风险(OR=0.52,95CI=0.34-0.81),男性(OR=0.58,95CI=0.38-0.87),非吸烟者(OR=0.58,95CI=0.41-0.83)和非饮酒者的OR(95CI)为0.66(0.46-0.93)。功能测定表明,在HCT116和LOVO结肠癌细胞中,由具有rs1927914A等位基因的TLR4启动子驱动的荧光素酶活性高5.43和2.07倍,分别,与包含rs1927914G等位基因的启动子驱动的结果相比。电泳迁移率变化分析(EMSA)结果表明rs1927914G等位基因增强转录因子结合。使用转录因子预测工具,我们发现G等位基因有助于抑制转录因子Oct1的结合,而A等位基因则不会。
结论:TLR4rs1927914多态性影响结肠癌的易感性,G等位基因通过调节基因表达提供保护作用。这些见解增强了我们对结肠癌风险的遗传决定因素的理解,并强调TLR4是癌症预防策略的有希望的目标。
BACKGROUND: Colon cancer remains a major health concern worldwide, with genetic factors playing a crucial role in its development. Toll-like receptors (TLRs) has been implicated in various cancers, but their role in colon cancer is not well understood. This study aims to identify functional polymorphisms in the promoter and 3\'UTR regions of TLRs and evaluate their association with colon cancer susceptibility.
METHODS: We conducted a case-control study involving 410 colon cancer patients and 410 healthy controls from the Chinese population. Genotyping of polymorphisms in TLR3, TLR4, TLR5 and TLR7 was performed using PCR-RFLP and TaqMan MGB probes. Using logistic regression analysis, we evaluated the association of TLRs polymorphisms and the susceptibility to colon cancer. To understand the biological implications of the TLR4 rs1927914 polymorphism, we conducted functional assays, including luciferase reporter assay and electrophoretic mobility shift assay (EMSA).
RESULTS: Our results demonstrated that the G-allele of the TLR4 rs1927914 polymorphism is significantly associated with a decreased risk of colon cancer (OR = 0.68, 95%CI = 0.50-0.91). Stratified analysis showed that TLR4 rs1927914 AG or GG genotype contributed to a decreased risk of colon cancer among younger individuals (OR = 0.52, 95%CI = 0.34-0.81), males (OR = 0.58, 95%CI = 0.38-0.87), non-smokers (OR = 0.58, 95%CI = 0.41-0.83) and non-drinker with OR (95%CI) of 0.66 (0.46-0.93). Functional assays demonstrated that in HCT116 and LOVO colon cancer cells, the luciferase activity driven by the TLR4 promoter with the rs1927914A allele was 5.43 and 2.07 times higher, respectively, compared to that driven by the promoter containing the rs1927914G allele. Electrophoretic mobility shift assay (EMSA) results indicated that the rs1927914G allele enhanced transcription factor binding. Using the transcription factor prediction tool, we found that the G allele facilitates binding of the repressive transcription factor Oct1, while the A allele does not.
CONCLUSIONS: The TLR4 rs1927914 polymorphism influence the susceptibility to colon cancer, with the G allele offering a protective effect through modulation of gene expression. These insights enhance our understanding of the genetic determinants of colon cancer risk and highlight TLR4 as a promising target for cancer prevention strategies.