Abstract：
OBJECTIVE: Cushing\'s syndrome is characterized by high morbidity and mortality with high interindividual variability. Easily measurable biomarkers, in addition to the hormone assays currently used for diagnosis, could reflect the individual biological impact of glucocorticoids. The aim of this study is to identify such biomarkers through the analysis of whole blood transcriptome.
METHODS: Whole blood transcriptome was evaluated in 57 samples from patients with overt Cushing\'s syndrome, mild Cushing\'s syndrome, eucortisolism, and adrenal insufficiency. Samples were randomly split into a training cohort to set up a Cushing\'s transcriptomic signature and a validation cohort to assess this signature.
METHODS: Total RNA was obtained from whole blood samples and sequenced on a NovaSeq 6000 System (Illumina). Both unsupervised (principal component analysis) and supervised (Limma) methods were used to explore the transcriptome profile. Ridge regression was used to build a Cushing\'s transcriptome predictor.
RESULTS: The transcriptomic profile discriminated samples with overt Cushing\'s syndrome. Genes mostly associated with overt Cushing\'s syndrome were enriched in pathways related to immunity, particularly neutrophil activation. A prediction model of 1500 genes built on the training cohort demonstrated its discriminating value in the validation cohort (accuracy .82) and remained significant in a multivariate model including the neutrophil proportion (P = .002). Expression of FKBP5, a single gene both overexpressed in Cushing\'s syndrome and implied in the glucocorticoid receptor signaling, could also predict Cushing\'s syndrome (accuracy .76).
CONCLUSIONS: Whole blood transcriptome reflects the circulating levels of glucocorticoids. FKBP5 expression could be a nonhormonal marker of Cushing\'s syndrome.
METHODS: Whole blood transcriptome was evaluated in 57 samples from patients with overt Cushing\'s syndrome, mild Cushing\'s syndrome, eucortisolism, and adrenal insufficiency. Samples were randomly split into a training cohort to set up a Cushing\'s transcriptomic signature and a validation cohort to assess this signature.
METHODS: Total RNA was obtained from whole blood samples and sequenced on a NovaSeq 6000 System (Illumina). Both unsupervised (principal component analysis) and supervised (Limma) methods were used to explore the transcriptome profile. Ridge regression was used to build a Cushing\'s transcriptome predictor.
RESULTS: The transcriptomic profile discriminated samples with overt Cushing\'s syndrome. Genes mostly associated with overt Cushing\'s syndrome were enriched in pathways related to immunity, particularly neutrophil activation. A prediction model of 1500 genes built on the training cohort demonstrated its discriminating value in the validation cohort (accuracy .82) and remained significant in a multivariate model including the neutrophil proportion (P = .002). Expression of FKBP5, a single gene both overexpressed in Cushing\'s syndrome and implied in the glucocorticoid receptor signaling, could also predict Cushing\'s syndrome (accuracy .76).
CONCLUSIONS: Whole blood transcriptome reflects the circulating levels of glucocorticoids. FKBP5 expression could be a nonhormonal marker of Cushing\'s syndrome.
摘要：
目的：库欣综合征的特点是发病率和死亡率高，个体间差异大。容易测量的生物标志物，除了目前用于诊断的激素检测，可以反映糖皮质激素对个体生物学的影响。这项研究的目的是通过全血转录组的分析来鉴定此类生物标志物。
方法：从明显库欣综合征患者的57个样本中评估全血转录组，轻度库欣综合征,全心畸形和肾上腺功能不全。样本被随机分成一个训练队列，以建立库欣的转录组签名，和一个验证队列来评估这个签名。
方法：从全血样品中获得总RNA，并在NovaSeq6000系统（Illumina）上进行测序。无监督（主成分分析）和监督（Limma）方法均用于探索转录组概况。Rigde回归用于构建库欣转录组预测因子。
结果：转录组分析区分了明显库欣综合征的样本。主要与明显库欣综合征相关的基因富集在与免疫相关的通路中，特别是中性粒细胞激活。在训练队列上构建的1500个基因的预测模型在验证队列中显示出其区分值(准确度0.82),并且在包括嗜中性粒细胞比例的多变量模型中保持显著(p=0.002)。FKBP5的表达，这是在库欣综合征中过度表达并暗示糖皮质激素受体信号传导的单个基因，还可以预测库欣综合征(准确率0.76)。
结论：全血转录组反映了糖皮质激素的循环水平。FKBP5表达可能是库欣综合征的非激素标志物。
方法：从明显库欣综合征患者的57个样本中评估全血转录组，轻度库欣综合征,全心畸形和肾上腺功能不全。样本被随机分成一个训练队列，以建立库欣的转录组签名，和一个验证队列来评估这个签名。
方法：从全血样品中获得总RNA，并在NovaSeq6000系统（Illumina）上进行测序。无监督（主成分分析）和监督（Limma）方法均用于探索转录组概况。Rigde回归用于构建库欣转录组预测因子。
结果：转录组分析区分了明显库欣综合征的样本。主要与明显库欣综合征相关的基因富集在与免疫相关的通路中，特别是中性粒细胞激活。在训练队列上构建的1500个基因的预测模型在验证队列中显示出其区分值(准确度0.82),并且在包括嗜中性粒细胞比例的多变量模型中保持显著(p=0.002)。FKBP5的表达，这是在库欣综合征中过度表达并暗示糖皮质激素受体信号传导的单个基因，还可以预测库欣综合征(准确率0.76)。
结论：全血转录组反映了糖皮质激素的循环水平。FKBP5表达可能是库欣综合征的非激素标志物。
