PO.TB03.05 · 肿瘤生物学
NOVA1调控CD44的选择性剪接以抑制乳腺癌侵袭和转移
NOVA1 regulates alternative splicing of CD44 to suppress breast cancer invasion and metastasis
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
背景：异常的选择性剪接(AS)通过增强细胞可塑性、侵袭和转移促进乳腺癌进展。NOVA1是一种神经元特异性RNA结合蛋白和剪接调控因子，已被牵涉于多种疾病，但其在乳腺癌中的作用仍不清楚。
方法：使用TCGA和GSEA数据集分析NOVA1的表达和临床病理相关性，并通过RT-qPCR、Western印迹和免疫组化在患者样本中验证。在NOVA1过表达或敲低后进行功能实验(划痕愈合、transwell侵袭和小鼠转移模型)。转录组测序和AS分析鉴定了NOVA1调控的剪接事件，随后进行了聚焦于CD44异构体的验证和挽救实验。
结果：对来自TCGA数据集的89对原发性乳腺癌与匹配的癌旁正常组织的分析显示，NOVA1是差异表达最显著的剪接因子之一。NOVA1在乳腺癌中表达降低，并与良好预后相关。NOVA1过表达抑制迁移、侵袭和转移，并抑制上皮-间质转化(EMT)。转录组分析表明NOVA1调控细胞外基质构筑和CD44的选择性剪接，导致促转移异构体CD44v6的表达降低。相反，NOVA1沉默增加CD44v6表达并增强转移潜能。罗格列酮(Rosiglitazone)处理恢复了NOVA1表达并降低了癌细胞侵袭性。
结论：NOVA1通过抑制CD44v6介导的EMT发挥转移抑制因子的作用，在乳腺癌中建立了一个新的NOVA1-CD44v6剪接轴。药理学诱导NOVA1可能代表一种限制转移进展的有希望的策略。
查看英文原文 English abstract
Background: Aberrant alternative splicing (AS) promotes breast cancer progression by enhancing cellular plasticity, invasion, and metastasis. NOVA1, a neuron-specific RNA-binding protein and splicing regulator, has been implicated in multiple diseases, but its role in breast cancer remains unclear.
Methods: NOVA1 expression and clinicopathologic relevance were analyzed using TCGA and GSEA datasets and validated in patient samples by RT-qPCR, Western blotting, and immunohistochemistry. Functional assays (wound healing, transwell invasion, and mouse metastasis models) were performed following NOVA1 overexpression or knockdown. Transcriptomic sequencing and AS analyses identified NOVA1-regulated splicing events, followed by validation and rescue experiments focusing on CD44 isoforms.
Results: Analysis of 89 paired primary breast carcinomas and matched adjacent normal tissues from the TCGA dataset revealed that NOVA1 is among the most differentially expressed splicing factors. NOVA1 expression was reduced in breast cancer and associated with favorable prognosis. NOVA1 overexpression inhibited migration, invasion, and metastasis and suppressed epithelial-mesenchymal transition (EMT). Transcriptome profiling indicated that NOVA1 regulates extracellular matrix organization and alternative splicing of CD44 , leading to reduced expression of the pro-metastatic isoform CD44v6. Conversely, NOVA1 silencing increased CD44v6 expression and enhanced metastatic potential. Rosiglitazone treatment restored NOVA1 expression and reduced cancer cell invasiveness.
Conclusions: NOVA1 functions as a metastasis suppressor by repressing CD44v6-mediated EMT, establishing a novel NOVA1-CD44v6 splicing axis in breast cancer. Pharmacologic induction of NOVA1 may represent a promising strategy to limit metastatic progression.
利益披露 Disclosure
J. Huang, None..
H. Hu, None.