单细胞和批量 RNA 测序的综合分析揭示了结直肠癌中铜死亡相关基因的预后模型和肿瘤微环境重塑机制。

BACKGROUND: Recently, there has been a great deal interest in cuproptosis, a form of programmed cell death that is mediated by copper. The specific mechanism through which cuproptosis-related genes impact the development of colorectal cancer (CRC) remains unknown. METHODS: Here, we combined bulk RNA-seq with scRNA-seq to investigate the CRGs functions within CRC. A number of 61 cuproptosis-related genes were chosen for further investigation. Nine prognostic CRGs were identified by Lasso-Cox. The RiskScore was created and the patients have been separated into two different groups, low- and high-RiskScore group. The CIBERSORT, ESTIMATE, MCP-counter, TIDE, and IPS have been employed to score the TME, and GSVA and GSEA were utilized to evaluate the pathway within the both groups. Further, we used cell communication analysis to explore the tumor microenvironment remodeling mechanisms of the COX17 and DLAT based on scRNA-seq. Finally, we used IHC and qPCR to validate the expression of COX17 and DLAT. RESULTS: AOC3, CCS, CDKN2A, COX11, COX17, COX19, DLD, DLAT, and PDHB have been recognized as prognostic CRGs in CRC. The high-risk group exhibited the worst prognosis, an immune-deficient phenotype, and were more resistant to ICB treatment. Further, scRNA-seq analysis revealed that elevated expression of COX17 in CD4-CXCL13Tfh could contribute to the immune evasion while DLAT had the opposite effect, reversing T cell exhaustion and inducing pyroptosis to boost CD8-GZMKT infiltration. CONCLUSIONS: The current investigation has developed a prognostic framework utilizing cuproptosis-related genes that is highly effective in predicting prognosis, TME type, and response to immunotherapy in CRC patients. Furthermore, our study reveals a novel finding that elevated levels of COX17 expression within CD4-CXCL13 T cells in CRC mediates T cell exhaustion and Treg infiltration, while DLAT has been found to facilitate the anti-tumor immunity activation through the T cell exhaustion reversal and the induction of pyroptosis.

背景：最近，人们对铜死亡这种由铜介导的程序性细胞死亡形式产生了浓厚的兴趣。铜死亡相关基因影响结直肠癌（CRC）发展的具体机制尚不清楚。

方法：在这里，我们结合 bulk RNA-seq 和 scRNA-seq 来研究 CRC 中 CRGs 的功能。选择了 61 个铜死亡相关基因进行进一步研究。通过 Lasso-Cox 确定了 9 个预后 CRGs。创建了 RiskScore，并将患者分为低风险和高风险两组。使用 CIBERSORT、ESTIMATE、MCP-counter、TIDE 和 IPS 对 TME 进行评分，使用 GSVA 和 GSEA 对两组中的通路进行评估。此外，我们使用细胞通讯分析基于 scRNA-seq 探索 COX17 和 DLAT 的肿瘤微环境重塑机制。最后，我们使用 IHC 和 qPCR 验证 COX17 和 DLAT 的表达。

结果：AOC3、CCS、CDKN2A、COX11、COX17、COX19、DLD、DLAT 和 PDHB 被认为是 CRC 中的预后 CRGs。高危组预后最差，表现为免疫缺陷表型，对 ICB 治疗的抵抗力更强。此外，scRNA-seq 分析显示 CD4-CXCL13Tfh 中 COX17 的高表达有助于免疫逃逸，而 DLAT 则产生相反的效果，逆转 T 细胞衰竭并诱导细胞焦亡以促进 CD8-GZMKT 浸润。

结论：本研究利用铜死亡相关基因构建了一种预测 CRC 患者预后、TME 类型和对免疫治疗反应的有效预后框架。此外，我们的研究揭示了一个新发现，即在 CRC 中 CD4-CXCL13 T 细胞中 COX17 表达水平升高介导 T 细胞衰竭和 Treg 浸润，而 DLAT 通过逆转 T 细胞衰竭和诱导细胞焦亡促进抗肿瘤免疫激活。