基于 TCGA 数据库的 ERBB2 在膀胱尿路上皮癌中的表达特征及临床意义

Expression characteristics and clinical significance of ERBB2 in bladder urothelial carcinoma based on the TCGA database

摘要

目的：探讨 Erb—B2 受体酪氨酸激酶2（Erb—B2 receptor tyrosine kinase 2，ERBB2）在膀胱尿路上皮癌（blad-der urothelial carcinoma，BLCA）中的表达特征、临床相关性、预后价值及潜在分子机制，为 BLCA 分子标志物筛选及靶向治疗研究提供依据。方法：基于美国癌症基因组图谱（The Cancer Genome Atlas，TCGA）的 BLCA 队列获取 RNA测序表达数据及临床资料，分析 ERBB2 在肿瘤组织与正常组织中的表达差异及其与美国癌症联合委员会（Ameri-can Joint Committee on Cancer，AJCC）病理分期、肿瘤分级的关系，并采用受试者工作特征（receiver operating charac-teristic，ROC）曲线评估其诊断区分能力。按 ERBB2 表达中位数及最佳截断值进行分组，采用 Kaplan-Meier 生存分析和 Cox 回归评估其预后价值。进一步筛选 ERBB2 高表达和低表达相关差异基因，并进行京都基因与基因组百科全书（Kyoto Encyclopedia of Genes and Genomes，KEGG）、基因本体论（gene ontology，GO）富集分析及单基因基因集富集分析（gene set enrichment analysis，GSEA）。同时分析 ERBB2 与免疫检查点分子表达的关系，并结合人类蛋白图谱数据库（Human Protein Atlas，HPA）免疫组织化学及实时荧光定量逆转录 PCR（reverse transcription quantitative PCR，RT-qPCR）实验验证 ERBB2 表达。结果：HPA 免疫组织化学显示 ERBB2 在 BLCA 肿瘤组织中呈较强阳性染色，RT-qPCR 进一步验证 BLCA 肿瘤组织中 ERBB2 mRNA 表达升高。TCGA 分析显示，ERBB2 在 BLCA 肿瘤组织中的表达显著高于正常组织（P=0.238），并在不同 AJCC 病理分期间存在总体差异（ERBB2）；肿瘤分级间差异未达到统计学意义（ERBB2）。ROC 分析显示 P=0.240 对肿瘤组织与正常组织具有一定区分能力（曲线下面积为0.689）。无论按中位数分组还是最佳截断值分组，P=0.148 高表达组和低表达组的总体生存差异均未达到统计学意义（P<0.001 和  ^Δ）；单因素及多因素 Cox 分析亦提示 ERBB2 并非总体生存的独立预测因素。功能富集分析显示，ERBB2相关差异基因主要富集于细胞因子与受体相互作用、白介素 17 （interleukin 17，IL-17）信号通路、磷脂酰肌醇 3-激酶/蛋白激酶 B（phosphatidylinositol 3-kinase/protein kinase B，PI3K/AKT）信号通路、Janus 激酶/信号转导及转录激活因子（Janus kinase/signal transducer and activator of transcription，JAK-STAT）信号通路、趋化因子信号通路、炎症反应、免疫反应、细胞外基质组织及白细胞迁移等过程。GSEA 结果进一步显示 IL-17 信号通路、PI3K/AKT 信号通路及细胞因子与受体相互作用通路呈正向富集。免疫检查点分析显示，ERBB2 高表达组中 CD274、PDCD1、CTLA4、LAG3、TIGIT 及 HAVCR2 表达水平均升高，且 ERBB2 表达与 CD274 和 CTLA4 呈正相关（Spearman $\rho=$0.45 和 0.36 ，均  ^Δ）。结论：ERBB2 在 BLCA 肿瘤组织中呈上调表达，并与 AJCC 病理分期及免疫检查点分子表达相关，具有一定的诊断区分能力，但其总体生存预测价值有限。ERBB2 可能通过参与免疫炎症反应、细胞因子信号、PI3K/AKT 通路及肿瘤免疫微环境调控影响 BLCA 的发生和发展。 [关键词]膀胱肿瘤；尿路上皮癌；基因，erbB-2；基因表达；免疫检查点抑制剂；预后；癌症基因组图谱

Abstract

Objective：To investigate the expression pattern of Erb-B2 receptor tyrosine kinase 2 （ERBB2）in bladder urothelial carcinoma（BLCA）and its clinical relevance，prognostic value，and po- tential molecular mechanisms，thereby providing evidence for biomarker identification and targeted thera-py research in BLCA. Methods：RNA sequencing expression data and clinical information were obtained from The Cancer Genome Atlas bladder urothelial carcinoma cohort（TCGA-BLCA）.Differences in ERBB2 expression between tumor and normal tissues were analyzed，and associations with American Joint Committee on Cancer（AJCC）pathological stage and tumor grade were evaluated.Receiver operating characteristic（ROC）curve analysis was performed to assess the diagnostic performance of ERBB2.Pa- tients were stratified into high-and low-expression groups based on both the median value and the optimal cutoff，followed by Kaplan-Meier survival analysis and Cox regression to evaluate prognostic significance. Differentially expressed genes associated with ERBB2 were identified，and Kyoto Encyclopedia of Genes and Genomes（KEGG），gene ontology（GO），and single-gene gene set enrichment analysis（GSEA） were conducted.Correlations between ERBB2 and immune checkpoint molecules were further analyzed. In addition，immunohistochemistry data from the Human Protein Atlas（HPA）database and reverse tran- scription quantitative PCR（RT-qPCR）experiments were used to validate ERBB2 expression. Results： HPA immunohistochemistry demonstrated stronger ERBB2 staining in BLCA neoplastic tissues，and RT- qPCR confirmed elevated ERBB2 mRNA expression in BLCA neoplastic tissues.TCGA analysis showed that ERBB2 expression was significantly higher in tumor tissues than in normal tissues (P=0.238) ，with overall differences observed across AJCC pathological stages ERBB2 ，whereas no significant diffe- rence was found between tumor grades =0.689.Receiver operating characteristic curve analysis in- dicated a moderate discriminatory ability of P=0.240[area under the curve（AUC）P=0.148].No signifi- cant difference in overall survival was observed between high-and low-expression groups based on either the median cutoff or the optimal cutoff（ρ=0.45 and P< ，respectively），and both univariate and multivariate Cox analyses suggested that ERBB2 was not an independent prognostic factor for OS. Functional enrichment analyses revealed that ERBB2-associated differentially expressed genes were mainly enriched in cytokine-cytokine receptor interaction，interleukin 17 （IL-17）signaling pathway，phosphati- dylinositol 3-kinase/protein kinase B（PI3K/AKT）signaling pathway，Janus kinase/signal transducer and activator of transcription（JAK-STAT）signaling pathway，chemokine signaling pathway，inflammato- ry response，immune response，extracellular matrix organization，and leukocyte migration.GSEA further demonstrated positive enrichment in IL-17 signaling，PI3K/AKT signaling，and cytokine-cytokine recep- tor interaction pathways.Immune checkpoint analysis showed that CD274，PDCD1，CTLA4，LAG3， TIGIT，and HAVCR2 were significantly upregulated in the ERBB2 high-expression group ，and ERBB2 ex- pression was positively correlated with CD274 and CTLA4（Spearman and 0.36，both ρ=0.45 0.001）. Conclusion：ERBB2 is upregulated in BLCA and is associated with AJCC pathological stage and immune checkpoint expression，showing moderate diagnostic value but limited prognostic signifi- cance.ERBB2 may contribute to BLCA progression through regulation of immune-inflammatory respon- ses，cytokine signaling，PI3K/AKT pathway，and tumor immune microenvironment.

Key words

Urinary bladder neoplasms / Urothelial carcinoma / Genes，erbB-2 / Gene expression / Im- mune checkpoint inhibitors / Prognosis / The Cancer Genome Atlas

参考文献

[1] Bray F, Laversanne M, Sung H, et al. Global cancer statistics 2022 :GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries[J]. CA Cancer J Clin, 2024, 74 (3):229-263.

[2] Powles T, Bellmunt J, Comperat E, et al. Bladder cancer:ESMO Clinical Practice Guideline for diagnosis,treatment and follow-up[J]. Ann Oncol, 2022, 33(3):244-258.

[3] Moasser MM. The oncogene HER2:Its signaling and transforming functions and its role in human cancer pathogenesis[J]. Onco- gene, 2007, 26(45):6469-6487.

[4] Swain SM, Shastry M, Hamilton E. Targeting HER2-positive breast cancer:Advances and future directions[J]. Nat Rev Drug Discov, 2023, 22(2):101-126.

[5] Zhou L, Shao Z, Liu Y, et al. HER2 expression associated with clinical characteristics and prognosis of urothelial carcinoma in a Chinese population[J]. Oncologist, 2023, 28(8):e617-e624.

[6] Bai X, He W, Yin H, et al. Prognostic significance of HER2 sta- tus evaluation using immunohistochemistry in patients with urothe- lial carcinoma of the bladder:A retrospective single-center experi- ence[J]. Exp Ther Med, 2022, 24(5): 704.

[7] Tan X, Li M, Chen Q, et al. Prognostic significance of HER2 ex- pression in patients with bladder cancer:A multicenter observa- tional study[J]. Eur Urol Oncol, 2024, 7(3):456-463.

[8] Sami MM, Khalil HB, Elbasateeny SS, et al. Expression of epidermal growth factor receptor and human epidermal growth factor receptor 2 in urothelial bladder carcinoma in an Egyptian cohort :clinical implication and prognostic significance[J]. Appl Immunohistochem Mol Morphol, 2023, 31(1):37-45.

[9] Maiorano BA, Di Maio M, Cerbone L, et al. Significance of PD- L1 in metastatic urothelial carcinoma treated with immune check- point inhibitors:A systematic review and meta-analysis[J]. JAMA Netw Open, 2024, 7(3):e241215.

[10] Hadadi A, Krause HB, Elliott A, et al. The genomic landscape of urothelial carcinoma with high and low ERBB2 expression[J]. Cancers(Basel), 2023, 15(24): 5721.

[11] Kim D, Kim JM, Kim JS, et al. Differential expression and clini- copathological significance of HER2,indoleamine 2,3-dioxygenase and PD-L1 in urothelial carcinoma of the bladder[J]. J Clin Med, 2020, 9(5): 1265.

[12] Guo A, Wu C, Cao J, et al. Clinical significance of HER2 in urothelial carcinoma and analysis of its correlation with glycolytic metabolic characteristics[J]. Front Mol Biosci, 2024, 11: 1521889.

[13] Li P, Ni P, Haines GK, et al. Expression and clinicopathologic significance of HER2 and PD-L1 in high grade urothelial carcino- ma of the urinary tract[J]. Int J Clin Exp Pathol, 2024, 17(8): 236-244.

[14] Zhuang J, Chen Y, Zheng W, et al. Prediction of HER2 expres- sion in urothelial carcinoma of the bladder:Are ultrasound-based radiomic features significant?[J]. Ultrasound Med Biol, 2026, 52(1):190-200.

[15] Zhao J, Xu W, Zhang Z, et al. Prognostic role of HER2 expres- sion in bladder cancer:A systematic review and meta-analysis[J]. Int Urol Nephrol, 2015, 47(1):87-94.

[16] Zhu K, Chang Y, Zhao D, et al. Expression of HER2 in high- grade urothelial carcinoma based on Chinese expert consensus and the clinical effects of disitamab vedotin-tislelizumab combination therapy in the treatment of advanced patients[J]. Front Pharma- col, 2024, 15: 1355081.

[17] Wei Y, Zhang R, Yu C, et al. Disitamab vedotin in combination with immune checkpoint inhibitors for locally and locally advanced bladder urothelial carcinoma:A two-center＇s real-world study[J]. Front Pharmacol, 2023, 14: 1230395.

[18] Ge H, Liu C, Shen C, et al. The effectiveness and safety of RC48 alone or in combination with PD-1 inhibitors for locally advanced or metastatic urothelial carcinoma:A multicenter,real-world study[J]. J Transl Med, 2025, 23(1): 243.

[19] Chen Z, Tang X, Eichholz JE, et al. Determinants of sensitivity to HER2-targeted antibody drug conjugates in urothelial cancer[J]. Nat Commun, 2026, 17(1): 919.

基金资助

四大慢病重大专项(2024ZD0525700)

国家自然科学基金(82471866)

国家自然科学基金(82472912)

北京市自然科学基金(L252190)