Agricultural Institute of Slovenia, Hacquetova ulica 17, SI-1000 Ljubljana, Slovenia.
Institute of Pathology, Faculty of Medicine, University of Ljubljana, Korytkova 2, SI-1000 Ljubljana, Slovenia.
Genes (Basel). 2023 Aug 17;14(8):1636. doi: 10.3390/genes14081636.
Cell-free DNA (cfDNA) from patient blood is emerging as a noninvasive diagnostic avenue for various cancers. We aimed to identify reliable biomarkers in cfDNA by investigating genes exhibiting significant differences between colorectal cancer and control samples. Our objective was to identify genes that showed a positive difference between cancer and control samples. To achieve this, we conducted an in silico analysis to identify genes that exhibit no significant variation in methylation between genomic DNA (gDNA) and cfDNA. We collected experimental data from publicly available repositories, which included 5-hydroxymethylcytosine (5hmC) profiles of gDNA and cfDNA samples from both cancer patients and healthy individuals. By comparing and overlapping these two groups, we identified 187 genes of interest, of which 53 genes had a positive difference among colon cancer patients and healthy individuals. Next, we performed an ANOVA test on these genes, resulting in the identification of 12 genes that showed statistically significant higher levels of 5hmC in cfDNA and gDNA from cancer patients compared to healthy individuals. Additionally, we compared the 5hmC status of these genes between cfDNA and gDNA from cancer patients. Interestingly, we found that the 5hmC of the toll like receptor 4 () gene was not statistically different between cfDNA and gDNA from cancer patients, indicating consistency between cfDNA and gDNA. These findings have important implications, not only for experimental validation but also for the development of more sensitive and robust noninvasive methods to improve diagnostic, prognostic, and treatment options for colon cancer.
无细胞游离 DNA(cfDNA)源自患者血液,正在成为各种癌症的一种非侵入性诊断途径。我们旨在通过研究在结直肠癌和对照样本之间表现出显著差异的基因,来鉴定 cfDNA 中的可靠生物标志物。我们的目标是鉴定出在癌症和对照样本之间存在阳性差异的基因。为了实现这一目标,我们进行了一项计算机分析,以鉴定出在基因组 DNA(gDNA)和 cfDNA 之间甲基化没有显著差异的基因。我们从公共可用的存储库中收集了实验数据,其中包括来自癌症患者和健康个体的 gDNA 和 cfDNA 样本的 5-羟甲基胞嘧啶(5hmC)图谱。通过比较和重叠这两组数据,我们确定了 187 个感兴趣的基因,其中 53 个基因在结肠癌患者和健康个体之间存在阳性差异。接下来,我们对这些基因进行了方差分析(ANOVA)测试,结果确定了 12 个基因,它们在癌症患者的 cfDNA 和 gDNA 中表现出统计学上显著更高水平的 5hmC,而在健康个体中则较低。此外,我们比较了这些基因在癌症患者的 cfDNA 和 gDNA 中的 5hmC 状态。有趣的是,我们发现 Toll 样受体 4()基因的 5hmC 在癌症患者的 cfDNA 和 gDNA 之间没有统计学差异,表明 cfDNA 和 gDNA 之间具有一致性。这些发现不仅对实验验证具有重要意义,而且对开发更敏感和稳健的非侵入性方法以改善结直肠癌的诊断、预后和治疗选择也具有重要意义。