Bowden Michaela, Zhou Chensheng W, Zhang Sui, Brais Lauren, Rossi Ashley, Naudin Laurent, Thiagalingam Arunthi, Sicinska Ewa, Kulke Matthew H
Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.
IPSEN Innovation, Les Ulis, France.
Oncotarget. 2017 Apr 7;8(33):54331-54344. doi: 10.18632/oncotarget.16908. eCollection 2017 Aug 15.
Current diagnostic and prognostic blood-based biomarkers for neuroendocrine tumors are limited. MiRNAs have tumor-specific expression patterns, are relatively stable, and can be measured in patient blood specimens. We performed a multi-stage study to identify and validate characteristic circulating miRNAs in patients with metastatic small intestine neuroendocrine tumors, and to assess associations between miRNA levels and survival.
Using a 742-miRNA panel, we identified candidate miRNAs similarly expressed in 19 small intestine neuroendocrine tumors and matched plasma samples. We refined our panel in an independent cohort of plasma samples from 40 patients with metastatic small intestine NET and 40 controls, and then validated this panel in a second, large cohort of 120 patients with metastatic small intestine NET and 120 independent controls.
miRNA profiling of 19 matched small intestine neuroendocrine tumors and matched plasma samples revealed 31 candidate miRNAs similarly expressed in both tissue and plasma. We evaluated expression of these 31 candidate miRNAs in 40 independent cases and 40 normal controls, and identified 4 miRNAs (miR-21-5p, miR-22-3p, miR-29b-3p, and miR-150-5p) that were differently expressed in cases and controls (p<0.05). We validated these 4 miRNAs in a separate, larger panel of 120 cases and 120 controls. We confirmed that high circulating levels of miR-22-3p (p<0.0001), high levels of miR 21-5p, and low levels of miR-150-5p (p=0.027) were associated with the presence of metastatic small intestine NET. While levels of 29b-3p were lower in cases than in controls in both the initial cohort and the validation cohort, the difference in the validation cohort did not reach statistical significance. We further found that high levels of circulating miR-21-5p, high levels of circulating miR-22-3p and low levels of circulating miR-150-5p were each independently associated with shorter overall survival. A combined analysis using all three markers was highly prognostic for survival (HR 0.47, 95% CI 0.27-0.82).
Our study suggests that elevated circulating levels of miR-21-5p and miR-22-3p and low levels of miR-150-5p are characteristic in patients with metastatic small intestine neuroendocrine tumors, and further suggests that levels of these miRNAs are associated with overall survival. These observations provide the basis for further validation studies, as well as studies to assess the biological function of these miRNAs in small intestine neuroendocrine tumors.
目前用于神经内分泌肿瘤的基于血液的诊断和预后生物标志物有限。微小RNA（miRNA）具有肿瘤特异性表达模式，相对稳定，且可在患者血液样本中检测到。我们开展了一项多阶段研究，以识别和验证转移性小肠神经内分泌肿瘤患者中具有特征性的循环miRNA，并评估miRNA水平与生存之间的关联。
我们使用一个包含742种miRNA的检测板，在19例小肠神经内分泌肿瘤及其配对的血浆样本中识别出表达相似的候选miRNA。我们在一个独立队列（40例转移性小肠神经内分泌肿瘤患者的血浆样本和40例对照）中优化了检测板，然后在第二个大型队列（120例转移性小肠神经内分泌肿瘤患者和120例独立对照）中对该检测板进行了验证。
对19对匹配的小肠神经内分泌肿瘤及其配对血浆样本进行miRNA分析，发现31种候选miRNA在组织和血浆中表达相似。我们在40例独立病例和40例正常对照中评估了这31种候选miRNA的表达，鉴定出4种miRNA（miR-21-5p、miR-22-3p、miR-29b-3p和miR-150-5p）在病例和对照中表达差异有统计学意义（p<0.05）。我们在一个单独的、更大的队列（120例病例和120例对照）中验证了这4种miRNA。我们证实，循环中miR-22-3p水平升高（p<0.0001）、miR-21-5p水平升高以及miR-150-5p水平降低（p=0.027）与转移性小肠神经内分泌肿瘤的存在相关。虽然在初始队列和验证队列中，病例组中miR-29b-3p水平均低于对照组，但在验证队列中的差异未达到统计学意义。我们进一步发现，循环中miR-21-5p水平升高、miR-22-3p水平升高以及miR-150-5p水平降低均分别与较短的总生存期独立相关。使用所有这三种标志物进行的联合分析对生存具有高度预后价值（风险比0.47，95%置信区间0.27-0.82）。
我们的研究表明，转移性小肠神经内分泌肿瘤患者循环中miR-21-5p和miR-22-3p水平升高以及miR-150-5p水平降低具有特征性，并且进一步表明这些miRNA的水平与总生存期相关。这些观察结果为进一步的验证研究以及评估这些miRNA在小肠神经内分泌肿瘤中的生物学功能的研究提供了基础。
