Key Laboratory of Environment and Health, Ministry of Education and Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Gastrointestinal Surgery Department, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Arch Toxicol. 2020 Jan;94(1):295-303. doi: 10.1007/s00204-019-02600-9. Epub 2019 Oct 23.
GWAS-identified 10q22.3 loci with lead SNP rs704017 are significantly associated with CRC risk in both Asian and European populations. However, the functional mechanism of this region is unclear. In this study, we performed a fine-mapping analysis to identify the causal SNPs. To identify potential functional SNPs in linkage disequilibrium with the lead SNP, we searched for the potential target genes using a Hi-C database and an RNA interfering-based on-chip approach. The results indicated that rs12263636 (r = 0.41) showed the highest potential to be functional. It resided in a region with enhancer markers and a topologically associating domain. We found that RPS24 was the only gene that significantly promoted the proliferation rate of CRC cells and might have promoter-enhancer interaction with rs12263636. Dual-luciferase reporter assays confirmed that the risk alleles of two variants (rs3740253 and rs7071351) in RPS24 promoter could increase the expression of luciferase. Case control study consisting of 1134 cases and 2039 health controls confirmed that both the two variants were associated with risk of CRC (rs3740253: P = 0.0079, OR = 1.15, 95% CI 1.04-1.28; rs7071351: P = 0.0085, OR = 1.15, 95% CI 1.04-1.28). And plasmid containing mutant haplotypes containing all the three mutations (rs12263636 or rs3740253 and rs7071351) could most significantly increase luciferase expression, compared with any haplotype of the three mutations. The study explained the functional mechanism for the 10q22.3 loci and provided new insights into the prevention and treatment of CRC.
GWAS 鉴定的 10q22.3 位点的 lead SNP rs704017 与亚洲和欧洲人群的 CRC 风险显著相关。然而，该区域的功能机制尚不清楚。在这项研究中，我们进行了精细映射分析以确定因果 SNP。为了确定与 lead SNP 处于连锁不平衡的潜在功能 SNP，我们使用 Hi-C 数据库和基于 RNA 干扰的芯片方法搜索潜在的靶基因。结果表明，rs12263636(r=0.41) 具有最高的功能潜力。它位于具有增强子标记和拓扑关联域的区域。我们发现 RPS24 是唯一显著促进 CRC 细胞增殖率的基因，并且可能与 rs12263636 具有启动子-增强子相互作用。双荧光素酶报告基因检测证实，RPS24 启动子中两个变体(rs3740253 和 rs7071351)的风险等位基因可以增加荧光素酶的表达。由 1134 例病例和 2039 例健康对照组成的病例对照研究证实，这两个变体均与 CRC 风险相关(rs3740253：P=0.0079，OR=1.15，95%CI1.04-1.28；rs7071351：P=0.0085，OR=1.15，95%CI1.04-1.28)。与包含三个突变(rs12263636 或 rs3740253 和 rs7071351)的所有突变杂合子相比，含有突变杂合子的质粒可以最显著地增加荧光素酶的表达。该研究解释了 10q22.3 位点的功能机制，并为 CRC 的预防和治疗提供了新的见解。
