目的·探究miRNA表达失调在SHH激活型髓母细胞瘤（sonic hedgehog-activated subtype medulloblastoma，SHH-MB）中的作用，并比较裸鼠皮下同种异体移植模型与实体瘤患者的失调miRNA的相关特征。方法·使用鼠源SHH-MB细胞系（SmoWT和SMB56）建立裸鼠皮下同种异体移植模型。每种模型被随机分为以平滑蛋白受体抑制剂（smoothened inhibitor，SMOi）GDC-0449灌胃处理的实验组、以二甲基亚砜（dimethyl sulfoxide，DMSO）灌胃的对照组，并收取这4组裸鼠的肿瘤样本。采集出生后7 d（P7）及60 d（P60）的正常裸鼠的小脑组织作为P7正常小脑、P60正常小脑组。参照肿瘤样本，收取GDC-0449灌胃处理的P7正常裸鼠的小脑组织（P7小脑给药组）以及DMSO灌胃处理的P7正常裸鼠的小脑组织（P7小脑对照组）。分别采用mRNA测序（mRNA sequencing，mRNA-seq）和miRNA测序（microRNA sequencing，miRNA-seq）获得以上8组样本的mRNA和miRNA表达数据并进行样本表达谱相关性分析。通过差异表达分析系统解析：① 鼠源SHH-MB模型的肿瘤核心转录组特征。② 正常小脑发育相关的转录组特征。③ 肿瘤及发育小脑中Hedgehog（Hh）通路依赖和非Hh通路依赖的转录组特征。利用miRDB、TargetScan与miRTarBase数据库并结合mRNA差异表达结果，预测关键差异miRNA的靶基因。通过京都基因与基因组百科全书（Kyoto Encyclopedia of Genes and Genomes，KEGG）富集分析，解析靶基因涉及的核心信号通路。针对在P7发育小脑中鉴定到的Hh通路依赖的miR-204-5p，进行靶基因预测与靶基因KEGG通路富集分析。最后，搜集R2与基因表达综合数据库（Gene Expression Omnibus，GEO）中SHH-MB患者肿瘤及健康对照小脑的mRNA与miRNA表达数据，通过差异表达分析与韦恩分析评估差异表达miRNAs/mRNAs调控关系在人与小鼠之间的保守性。结果·样本mRNA表达谱相关性分析显示，SmoWT对照组与SMB56对照组的mRNA表达谱相似性较高；2个对照组与P7正常小脑组的相似性高于P60正常小脑组，而GDC-0449处理未显著改变这2个对照组的整体转录组特征。miRNA表达谱相关性分析结果与mRNA层面类似。SmoWT对照组、SMB56对照组与P7正常小脑、P60正常小脑组的差异表达分析鉴定出2个对照组中共同显著上调的95个miRNA、下调的126个miRNA；其中50个上调miRNA和38个下调miRNA在P7与P60正常小脑比较中同向表达。通过SmoWT实验组与SmoWT对照组、SMB56实验组与SMB56对照组的差异表达分析，鉴定出各模型中Hh通路与非Hh通路依赖的miRNA。韦恩分析显示，Hh通路依赖的miRNA（占差异miRNA总数的10%~20%）在模型间重叠极少；非Hh通路依赖的miRNA则在模型间高度保守。Hh通路依赖的差异表达miRNA的靶基因的KEGG通路富集结果显示，其富集于磷脂酰肌醇3激酶/蛋白激酶B信号通路（phosphoinositide 3-kinase/protein kinase B pathway，PI3K/AKT）、磷脂酶D（phospholipase D，PLD）、RAS/丝裂原活化蛋白激酶信号通路（RAS/mitogen-activated protein kinase pathway，RAS/MAPK）和DNA复制（DNA replication）通路。通过比较P7小脑给药组与P7小脑对照组，鉴定出P7小脑中7个Hh通路激活和1个Hh通路抑制的miRNA，285个Hh通路激活和72个Hh通路抑制的mRNA。miR-204-5p的靶基因富集于细胞周期通路。SHH-MB患者肿瘤与健康小脑对照样本的差异表达分析鉴定出22个人鼠保守的miRNA，其靶基因富集于环磷腺苷（cyclic adenosine monophosphate，cAMP）和细胞周期通路等。结论·鼠源SHH-MB模型表现出广泛的miRNA表达失调，但SMOi处理仅对其中小部分失调miRNA有逆转作用，提示Hh通路对miRNA失调的影响有限，并且仅有非Hh通路依赖的失调miRNA在2个鼠源模型之间表现出部分重叠。此外，SHH-MB鼠源模型与实体瘤患者来源的肿瘤有保守的失调miRNA特征。

Objective ·To investigate the role of miRNA expression dysregulation in sonic hedgehog-activated subtype medulloblastoma (SHH-MB), and to compare the dysregulated miRNA features between subcutaneous xenograft models in nude mice and patients with solid tumors. Methods ·Mouse SHH-MB cell lines (SmoWT and SMB56) were used to establish subcutaneous xenograft models in nude mice. For each model, mice were randomly divided into groups treated with the smoothened inhibitor (SMOi) GDC-0449 (SmoWT experimental group and SMB56 experimental group) or dimethyl sulfoxide (DMSO) (SmoWT control group and SMB56 control group), and tumor samples from these 4 groups were collected. Cerebellar tissues from normal P7 (postnatal day 7) and P60 nude mice were collected as controls (P7 normal cerebellum group and P60 normal cerebellum group). Following the same procedure, cerebellar tissues were also collected from P7 normal nude mice treated with GDC-0449 (P7 cerebellum treatment group) or DMSO (P7 cerebellum control group). mRNA sequencing (mRNA-seq) and microRNA sequencing (miRNA-seq) were performed on these eight sample groups to obtain mRNA and miRNA expression profiles. Subsequently, differential expression analysis was systematically employed to elucidate: ① the core transcriptomic features of tumors in mouse SHH-MB models; ② transcriptomic features associated with normal cerebellar development; ③ Hedgehog (Hh)-dependent and Hh-independent transcriptomic features in both tumors and developing cerebellum. Target genes of key differentially expressed miRNAs were predicted by integrating data from the miRDB, TargetScan, and miRTarBase databases, combined with mRNA differential expression results. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was then performed to identify core signaling pathways involving these target genes. Specifically, for the Hh-dependent miRNA miR-204-5p identified in the P7 developing cerebellum, target genes were predicted and subjected to KEGG pathway enrichment analysis. Finally, mRNA and miRNA expression profiles from SHH-MB patient tumors and healthy control cerebella were obtained from the R2 and Gene Expression Omnibus (GEO). Conservation of differentially expressed miRNAs/mRNAs and their regulatory relationships between humans and mice was then systematically assessed through differential expression and Venn analysis. Results ·Analysis of mRNA expression profile correlations revealed a high correlation between the SmoWT control and SMB56 control groups. Both tumor control groups showed higher correlation with the P7 normal cerebellum group than with the P60 normal cerebellum group. Treatment with GDC-0449 did not significantly alter the overall transcriptomic profiles of either control group. The miRNA expression profile correlation results were consistent with those observed in the mRNA profiles. Differential expression analysis comparing the SmoWT control and SMB56 control groups with the P7 and P60 normal cerebellum groups identified 95 commonly upregulated and 126 commonly downregulated miRNAs in the two control groups. Among these, 50 upregulated and 38 downregulated miRNAs showed the same expression trends in the P7 and P60 normal cerebellum comparison. Differential expression analysis between the SmoWT experimental and control groups and between the SMB56 experimental and control groups identified Hh-dependent and Hh-independent differentially expressed miRNAs in each model. Venn diagram showed that the Hh-dependent miRNAs (accounting for 10%-20% of all differentially expressed miRNAs) showed minimal overlap between mouse SHH-MB models, whereas Hh-independent miRNAs were highly conserved across models. KEGG pathway enrichment analysis of the target genes of Hh-dependent differentially expressed miRNAs showed significant enrichment in the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway, phospholipase D (PLD) pathway, RAS/mitogen-activated protein kinase (RAS/MAPK) pathway, and DNA replication pathways. Comparison between the P7 cerebellum treatment group and the P7 cerebellum control group identified 7 miRNAs and 285 mRNAs whose expression was promoted by the Hh pathway, and 1 miRNA and 72 mRNAs whose expression was inhibited by the Hh pathway in the P7 cerebellum. The target genes of miR-204-5p were enriched in the cell cycle pathway. Differential expression analysis of SHH-MB patient tumors vs healthy cerebellar controls identified 22 conserved human‑mouse miRNAs, with their target genes enriched in the cyclic adenosine monophosphate (cAMP) signaling pathway and the cell cycle pathway. Conclusion ·Mouse SHH-MB models exhibit extensive miRNA expression dysregulation. However, SMOi treatment reverses only a small subset of these dysregulated miRNAs, indicating a limited effect of the Hh pathway on miRNA dysregulation. Only Hh-independent dysregulated miRNAs show partial overlap between mouse SHH-MB models. Furthermore, there are conserved dysregulated miRNA features between mouse SHH-MB models and patients with solid tumors.