Department of Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, NO.277, West Yanta Road, Xi'an, 710061, Shaanxi, China.
Department of Second Medical Oncology, The 3201 Affiliated Hospital of Xi'an Jiaotong University, Hanzhong, Shaanxi, China.
BMC Bioinformatics. 2022 Sep 27;23(1):390. doi: 10.1186/s12859-022-04951-0.
Collagen VI family (COL6A) is a major member of extracellular matrix protein. There is accumulating evidence that COL6A is involved in tumorigenesis and tumor progression. In this study, we performed a systematic analysis of COL6A in pan-cancer based on their molecular features and clinical significance.
Based on updated public databases, we integrated several bioinformatics analysis methods to investigate the expression levels of COL6A as well as the relationship between their expression and patient survival, immune subtypes, tumor microenvironment, stemness scores, drug sensitivity, and DNA methylation.
The expression levels of COL6A members varied in different cancers, suggesting their expression was cancer-dependent. Among COL6A members, COL6A1/2/3 were predicted poor prognosis in specific cancers. Furthermore, COL6A1/2/3 expression levels revealed a clear correlation with immune subtypes, and COL6A1/2/3 were associated with tumor purity, that is, gene expression levels were generally higher in tumors with higher stromal scores and immune scores. COL6A1/2/3 had a significantly negative correlation with RNA stemness scores, and meanwhile they were also related to DNA stemness scores in different degrees. In addition, the expression of COL6A1/2/3 was significantly related to drug sensitivity of cancer cells. Finally, our study revealed that COL6A1/2/3 expression was mainly negatively correlated with gene methylation, and the methylation levels showed remarkable differences in various cancers.
These findings highlight both the similarities and differences in the molecular characteristics of COL6A members in pan-cancer, and provide comprehensive insights for further investigation into the mechanism of COL6A.
胶原 VI 家族（COL6A）是细胞外基质蛋白的主要成员。越来越多的证据表明 COL6A 参与肿瘤的发生和进展。在这项研究中，我们基于其分子特征和临床意义，对泛癌中的 COL6A 进行了系统分析。
基于更新的公共数据库，我们整合了几种生物信息学分析方法，研究了 COL6A 的表达水平及其与患者生存、免疫亚型、肿瘤微环境、干性评分、药物敏感性和 DNA 甲基化之间的关系。
COL6A 成员的表达水平在不同癌症中存在差异，提示其表达具有癌症依赖性。在 COL6A 成员中，COL6A1/2/3 在特定癌症中被预测为预后不良。此外，COL6A1/2/3 的表达水平与免疫亚型有明显的相关性，COL6A1/2/3 与肿瘤纯度有关，即基质评分和免疫评分较高的肿瘤中基因表达水平通常较高。COL6A1/2/3 与 RNA 干性评分呈显著负相关，同时与不同程度的 DNA 干性评分也有关。此外，COL6A1/2/3 的表达与癌细胞的药物敏感性显著相关。最后，我们的研究表明 COL6A1/2/3 的表达主要与基因甲基化呈负相关，并且在不同癌症中甲基化水平存在显著差异。
这些发现突出了泛癌中 COL6A 成员分子特征的相似性和差异性，为进一步研究 COL6A 的机制提供了全面的见解。
