J Natl Cancer Inst. 2019 Sep 1;111(9):983-995. doi: 10.1093/jnci/djy234.
A better definition of biomarkers and biological processes related to local recurrence and disease progression is highly warranted for ductal breast carcinoma in situ (DCIS). Stromal-epithelial interactions are likely of major importance for the biological, clinical, and pathological distinctions between high- and low-risk DCIS cases.
Stromal platelet derived growth factor receptor (PDGFR) was immunohistochemically assessed in two DCIS patient cohorts (n = 458 and n = 80). Cox proportional hazards models were used to calculate the hazard ratios of recurrence. The molecular mechanisms regulating stromal PDGFR expression were investigated in experimental in vitro co-culture systems of DCIS cells and fibroblasts and analyzed using immunoblot and quantitative real-time PCR. Knock-out of JAG1 in DCIS cells and NOTCH2 in fibroblasts was obtained through CRISPR/Cas9. Experimental data were validated by mammary fat pad injection of DCIS and DCIS-JAG1 knock-out cells (10 mice per group). All statistical tests were two-sided.
PDGFRα(low)/PDGFRβ(high) fibroblasts were associated with increased risk for recurrence in DCIS (univariate hazard ratio = 1.59, 95% confidence interval [CI] = 1.02 to 2.46; P = .04 Wald test; multivariable hazard ratio = 1.78, 95% CI = 1.07 to 2.97; P = .03). Tissue culture and mouse model studies indicated that this fibroblast phenotype is induced by DCIS cells in a cell contact-dependent manner. Epithelial Jagged1 and fibroblast Notch2 were identified through loss-of-function studies as key juxtacrine signaling components driving the formation of the poor prognosis-associated fibroblast phenotype.
A PDGFRα(low)/PDGFRβ(high) fibroblast subset was identified as a marker for high-risk DCIS. The Jagged-1/Notch2/PDGFR stroma-epithelial pathway was described as a novel signaling mechanism regulating this poor prognosis-associated fibroblast subset. In general terms, the study highlights epithelial-stromal crosstalk in DCIS and contributes to ongoing efforts to define clinically relevant fibroblast subsets and their etiology.
导管原位乳腺癌（DCIS）非常需要更好地定义与局部复发和疾病进展相关的生物标志物和生物学过程。间质-上皮相互作用对于高危和低危 DCIS 病例之间的生物学、临床和病理学区分可能非常重要。
在两个 DCIS 患者队列（n=458 和 n=80）中，使用免疫组织化学评估间质血小板衍生生长因子受体（PDGFR）。使用 Cox 比例风险模型计算复发的风险比。在 DCIS 细胞和成纤维细胞的体外共培养系统中研究调节间质 PDGFR 表达的分子机制，并使用免疫印迹和定量实时 PCR 进行分析。通过 CRISPR/Cas9 获得 DCIS 细胞中的 JAG1 和成纤维细胞中的 NOTCH2 敲除。通过 DCIS 和 DCIS-JAG1 敲除细胞（每组 10 只小鼠）的乳腺脂肪垫注射验证实验数据。所有统计检验均为双侧。
PDGFRα（低）/PDGFRβ（高）成纤维细胞与 DCIS 复发风险增加相关（单变量风险比=1.59，95%置信区间[CI]为 1.02 至 2.46；P=0.04 Wald 检验；多变量风险比=1.78，95%CI 为 1.07 至 2.97；P=0.03）。组织培养和小鼠模型研究表明，这种成纤维细胞表型是 DCIS 细胞以细胞接触依赖性方式诱导的。通过功能丧失研究鉴定出上皮 Jagged1 和成纤维细胞 Notch2 是驱动形成预后不良相关成纤维细胞表型的关键旁分泌信号成分。
鉴定出 PDGFRα（低）/PDGFRβ（高）成纤维细胞亚群作为高危 DCIS 的标志物。Jagged1/Notch2/PDGFR 基质-上皮途径被描述为调节这种预后不良相关成纤维细胞亚群的新信号机制。总的来说，该研究强调了 DCIS 中的上皮-间质相互作用，并为定义临床上相关的成纤维细胞亚群及其病因学做出了贡献。
