肿瘤弹性成像及其与乳腺肿瘤患者血浆中游离肿瘤DNA的关联：一项初步研究。

Tumor elastography and its association with cell-free tumor DNA in the plasma of breast tumor patients: a pilot study.

作者信息

Hao Yi, Yang Wei, Zheng Wenyi, Chen Xiaona, Wang Hui, Zhao Liang, Xu Jinfeng, Guo Xia

机构信息

Department of Ultrasound, South China Hospital of Shenzhen University, Shenzhen, China.

Department of Ultrasound, Shenzhen Hospital, Southern Medical University, Shenzhen, China.

出版信息

Quant Imaging Med Surg. 2021 Aug;11(8):3518-3534. doi: 10.21037/qims-20-443.

DOI:10.21037/qims-20-443

PMID:34341728

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8245960/

Abstract

BACKGROUND

Breast tumor stiffness, which can be objectively and noninvasively evaluated by ultrasound elastography (UE), has been useful for the differentiation of benign and malignant breast lesions and the prediction of clinical outcomes. Liquid biopsy analyses, including cell-free tumor DNA (ctDNA), exhibit great potential for personalized treatment. This study aimed to investigate the correlations between the UE and ctDNA for early breast cancer diagnosis.

METHODS

Breast tumor stiffness in 10 patients were assessed by shear wave elastography (SWE), and the ctDNA of eight collected plasma specimens with different tumor stiffness were analyzed by whole-genome sequencing (WGS). Subsequently, the distribution of carcinoma-associated fibroblasts (CAFs) was investigated by detecting the expression levels of alpha-smooth muscle actin (α-SMA) in tissues of breast lesions. We validated the function of discoidin domain receptor 2 (DDR2) in breast tumor CAFs by knockout of fibroblast activation protein (FAP) with different tumor stiffness during cancer progression and .

RESULTS

The UE estimates of tumor stiffness positively correlated with CAF-rich (α-SMA) tumors (P<0.05). Copy number profiles and percent genome alterations were remarkably different between benign and malignant breast lesions. Somatic genomic alterations or structural variants of , , , and genes were identified in ctDNA of plasma from breast lesions with high SWE values and an increase in the CAF content obtained from clinical samples. Deletion of FAP in breast tumor CAFs by CRISPR/Cas9-mediated gene knockout and decreased tumor stiffness resulted in downregulated expression of (P<0.05), which in turn led to decreasing the tumor stiffness and carcinogenesis process and .

CONCLUSIONS

These results have established proof of principle that WGS analysis of ctDNA could complement current UE approaches to assess tumor stiffness changes for the early diagnosis and prognostic assessment of breast cancer.

摘要

背景

乳腺肿瘤硬度可通过超声弹性成像（UE）进行客观、无创评估，有助于鉴别乳腺良恶性病变及预测临床结局。包括游离肿瘤DNA（ctDNA）在内的液体活检分析在个性化治疗方面具有巨大潜力。本研究旨在探讨UE与ctDNA在早期乳腺癌诊断中的相关性。

方法

采用剪切波弹性成像（SWE）评估10例患者的乳腺肿瘤硬度，对8份具有不同肿瘤硬度的采集血浆标本的ctDNA进行全基因组测序（WGS）分析。随后，通过检测乳腺病变组织中α平滑肌肌动蛋白（α-SMA）的表达水平，研究癌相关成纤维细胞（CAFs）的分布。我们通过在癌症进展过程中敲除不同肿瘤硬度下的成纤维细胞活化蛋白（FAP），验证了盘状结构域受体2（DDR2）在乳腺肿瘤CAFs中的功能。

结果

UE对肿瘤硬度的估计与富含CAF（α-SMA）的肿瘤呈正相关（P<0.05）。乳腺良恶性病变之间的拷贝数谱和基因组改变百分比存在显著差异。在SWE值高且临床样本中CAF含量增加的乳腺病变血浆ctDNA中，鉴定出了、、和基因的体细胞基因组改变或结构变异。通过CRISPR/Cas9介导的基因敲除在乳腺肿瘤CAFs中缺失FAP并降低肿瘤硬度，导致表达下调（P<0.05），进而导致肿瘤硬度和致癌过程降低。