Incorporating MicroRNA into Molecular Phenotypes of Circulating Tumor Cells Enhances the Prognostic Accuracy for Patients with Metastatic Breast Cancer

The molecular phenotype of circulating tumor cells (CTCs) was associated with clinical outcome of patients with breast cancer. CTCs isolated from patients with metastatic breast cancer (MBC) display a unique microRNA (miRNA) expression profile. The

The phenotypic assemblies of CTC incorporating miR-106b show enhanced prognostic accuracy of overall survival in patients with MBC. Implications for practice: In order to enhance the prognostic accuracy of the circulating tumor cell (CTC) phenotype in patients with metastatic breast cancer (MBC), this study screened and identified a CTC-specific microRNA (miRNA), miR-106b, as an upregulated molecule based on the comparison of miRNA profile between CTCs, primary tumors, and healthy blood donors. By incorporating miR-106b into a combined prediction model, the prognostic accuracy of the CTC phenotype for patients with MBC was greatly improved in both the training and validation cohorts. This work provides clinical evidence supporting the prognostic potential of CTC-specific miRNA for patients with MBC. These results indicate that developing CTC-specific miRNAs as new biomarkers will help to further optimize personalized therapy. 关键词。乳腺癌 • 循环肿瘤细胞 • 微小 RNA • 预后 • 转移 摘要 背景。循环肿瘤细胞 (CTC) 的分子表型与乳腺癌患者的临床结果相关。从转移性乳腺癌 (MBC) 患者中分离出的 CTC 显示出独特的微小 RNA(miRNA)表达谱。本研究的目的是通过将miRNA 添加进组合预测模型，来提高 MBC 患者 CTC 表型的预后准确性。 受试者、材料和方法。采用细胞搜索法检测 CTC，采用磁细胞分选法富集 CTC。采用miRNA 深度测序技术和定量聚合酶链反应筛选并验证可能的 CTC 特异性miRNA 候选物。从两个独立队列中纳入 MBC 患者，并分析总生存率 (OS) 和化疗反应。 结果。我们筛选并确定，与 CTC = 0/7.5 mL (n = 16) 的患者和健康供体(n = 8)相比，在 CTC ≥ 5/7.5 mL (n = 16)的 MBC 患者中，miR‐106b 是一种上调分子。CTC 特异性 miR‐106b 的表达与 CTC 中波形蛋白和 E‐钙粘蛋白相关，并作为预测 OS 的独立因素 [风险比 2.157，95% 置信区间 (CI)1.098–4.239，p = 0.026]。尽管 CTC 特异性 miR‐106b、E‐钙粘蛋白和波形蛋白各自显示了预后潜力，但基于三个标志物组合的 OS 预后表现在队列 1 [曲线下面积 (AUC)0.752，95% CI 0.658‐0.847，n = 128]中显著增强，并在队列 2(AUC 0.726，95% CI 0.595‐0.856， n = 91)中得到进一步验证。此外，包含 miR‐106b 的组合模型与治疗反应相关。 结论。包含 miR‐106b 的 CTC 表型组合显示，MBC 患者总生存率的预后准确性增强。 实践意义:为了提高转移性乳腺癌(MBC)患者循环肿瘤细胞(CTC)表型的预后准确性，本研究在比较 CTC、原发性肿瘤和健康供体之间的微小RNA (miRNA)谱的基础上，筛选并确定了一种 CTC 特异性miRNA，即 miR‐106b，作为上调分子。通过将 miR‐106b 添加进组合预测模型，在训练队列和验证队列中，MBC 患者 CTC 表型的预后准确性都有了很大提高。本研究提供了临床证据，证明 CTC 特异性miRNA 对 MBC 患者的预后潜力。这些结果表明，开发 CTC 特异性miRNA 作为新的生物标志物将有助于进一步优化个体化治疗。

CTCs were detected by CellSearch and enriched by magnetic cell sorting. miRNA deep sequencing and quantitative polymerase chain reaction were used to screen and verify potentially CTC-specific miRNA candidates. Patients with MBC were enrolled from two independent cohorts, and overall survival (OS) and chemotherapy response were analyzed.

We screened and identified that miR-106b was an upregulated molecule in patients with MBC with CTC ≥5/7.5 mL (n = 16) compared with patients with CTC = 0/7.5 mL (n = 16) and healthy donors (n = 8). The expression of CTC-specific miR-106b correlated with vimentin and E-cadherin in CTC and acted as an independent factor for predicting OS (hazard ratio 2.157, 95% confidence interval [CI] 1.098-4.239, p = .026). Although CTC-specific miR-106b, E-cadherin, and vimentin showed a prognostic potential independently, the prognostic performance for OS based on the combination of three markers was significantly enhanced in Cohort 1 (area under the curve [AUC] 0.752, 95% CI 0.658-0.847, n = 128) and further validated in Cohort 2 (AUC 0.726, 95% CI 0.595-0.856, n = 91). Besides, a combined model incorporating miR-106b was associated with therapy response.