Department of Pathology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China.
Department of Pain, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China.
Front Immunol. 2023 Jan 12;13:1055412. doi: 10.3389/fimmu.2022.1055412. eCollection 2022.
Medullary thyroid carcinoma (MTC), a thyroid C cell-derived malignancy, is poorly differentiated and more aggressive than papillary, follicular and oncocytic types of thyroid cancer. The current therapeutic options are limited, with a third of population suffering resistance. The differential gene expression pattern among thyroid cancer subtypes remains unclear. This study intended to explore the exclusive gene profile of MTC and construct a comprehensive regulatory network via integrated analysis, to uncover the potential key biomarkers.
Multiple datasets of thyroid and other neuroendocrine tumors were obtained from GEO and TCGA databases. Differentially expressed genes (DEGs) specific in MTC were identified to construct a transcription factor (TF)-mRNA-miRNA network. The impact of the TF-mRNA-miRNA network on tumor immune characteristics and patient survival was further explored by single-sample GSEA (ssGSEA) and ESTIMATE algorithms, as well as univariate combined with multivariate analyses. RT-qPCR, cell viability and apoptosis assays were performed for in vitro validation.
We identified 81 genes upregulated and 22 downregulated in MTC but not in other types of thyroid tumor compared to the normal thyroid tissue. According to the L1000CDS2 database, potential targeting drugs were found to reverse the expressions of DEGs, with panobinostat (S1030) validated effective for tumor repression in MTC by in vitro experiments. The 103 DEGs exclusively seen in MTC were involved in signal release, muscle contraction, pathways of neurodegeneration diseases, neurotransmitter activity and related amino acid metabolism, and cAMP pathway. Based on the identified 15 hub genes, a TF-mRNA-miRNA linear network, as well as REST-cored coherent feed-forward loop networks, namely REST-KIF5C-miR-223 and REST-CDK5R2-miR-130a were constructed via online prediction and validation by public datasets and our cohort. Hub-gene, TF and miRNA scores in the TF-mRNA-miRNA network were related to immune score, immune cell infiltration and immunotherapeutic molecules in MTC as well as in neuroendocrine tumor of lung and neuroblastoma. Additionally, a high hub-gene score or a low miRNA score indicated good prognoses of neuroendocrine tumors.
The present study uncovers underlying molecular mechanisms and potential immunotherapy-related targets for the pathogenesis and drug discovery of MTC.
甲状腺髓样癌（MTC）是一种甲状腺 C 细胞来源的恶性肿瘤，其分化程度较差，比甲状腺乳头状癌、滤泡癌和嗜酸细胞癌更为侵袭性。目前的治疗选择有限，有三分之一的患者会出现耐药。甲状腺癌亚型之间的差异基因表达模式仍不清楚。本研究旨在通过综合分析探索 MTC 的特有基因谱，并构建一个全面的调控网络，以揭示潜在的关键生物标志物。
从 GEO 和 TCGA 数据库中获取甲状腺和其他神经内分泌肿瘤的多个数据集。鉴定出特定于 MTC 的差异表达基因（DEGs），以构建转录因子（TF）-mRNA-miRNA 网络。通过单样本 GSEA（ssGSEA）和 ESTIMATE 算法以及单变量与多变量分析进一步探讨 TF-mRNA-miRNA 网络对肿瘤免疫特征和患者生存的影响。进行 RT-qPCR、细胞活力和凋亡测定以进行体外验证。
与正常甲状腺组织相比，我们在 MTC 中鉴定出 81 个上调和 22 个下调的基因，而在其他类型的甲状腺肿瘤中没有。根据 L1000CDS2 数据库，发现了一些潜在的靶向药物可以逆转 DEGs 的表达，体外实验表明帕比司他（S1030）对 MTC 的肿瘤抑制作用有效。在 MTC 中仅发现的 103 个 DEGs 参与信号释放、肌肉收缩、神经退行性疾病途径、神经递质活性和相关氨基酸代谢以及 cAMP 途径。基于鉴定的 15 个枢纽基因，通过在线预测和公共数据集以及我们的队列验证，构建了 TF-mRNA-miRNA 线性网络以及 REST-cored 相干前馈环网络，即 REST-KIF5C-miR-223 和 REST-CDK5R2-miR-130a。TF-mRNA-miRNA 网络中的枢纽基因、TF 和 miRNA 评分与 MTC 以及肺神经内分泌肿瘤和神经母细胞瘤中的免疫评分、免疫细胞浸润和免疫治疗分子有关。此外，高枢纽基因评分或低 miRNA 评分表明神经内分泌肿瘤预后良好。
本研究揭示了 MTC 发病机制和药物发现的潜在分子机制和潜在免疫治疗相关靶点。
