Division of Gastroenterology, Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, Ohio; University Hospitals Cleveland Medical Center, Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, Ohio; Division of Gastroenterology, Louis Stokes Veterans Affairs Medical Center, Cleveland, Ohio.
Division of General Medical Sciences-Oncology, Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, Ohio.
Gastroenterology. 2019 May;156(6):1761-1774. doi: 10.1053/j.gastro.2019.01.263. Epub 2019 Feb 12.
BACKGROUND & AIMS: Esophageal adenocarcinoma (EAC) is resistant to standard chemoradiation treatments, and few targeted therapies are available. We used large-scale tissue profiling and pharmacogenetic analyses to identify deregulated signaling pathways in EAC tissues that might be targeted to slow tumor growth or progression.
We collected 397 biopsy specimens from patients with EAC and nonmalignant Barrett's esophagus (BE), with or without dysplasia. We performed RNA-sequencing analyses and used systems biology approaches to identify pathways that are differentially activated in EAC vs nonmalignant dysplastic tissues; pathway activities were confirmed with immunohistochemistry and quantitative real-time polymerase chain reaction analyses of signaling components in patient tissue samples. Human EAC (FLO-1 and EsoAd1), dysplastic BE (CP-B, CP-C, CP-D), and nondysplastic BE (CP-A) cells were incubated with pharmacologic inhibitors or transfected with small interfering RNAs. We measured effects on proliferation, colony formation, migration, and/or growth of xenograft tumors in nude mice.
Comparisons of EAC vs nondysplastic BE tissues showed hyperactivation of transforming growth factor-β (TGFB) and/or Jun N-terminal kinase (JNK) signaling pathways in more than 80% of EAC samples. Immunohistochemical analyses showed increased nuclear localization of phosphorylated JUN and SMAD proteins in EAC tumor tissues compared with nonmalignant tissues. Genes regulated by the TGFB and JNK pathway were overexpressed specifically in EAC and dysplastic BE. Pharmacologic inhibition or knockdown of TGFB or JNK signaling components in EAC cells (FLO-1 or EsoAd1) significantly reduced cell proliferation, colony formation, cell migration, and/or growth of xenograft tumors in mice in a SMAD4-independent manner. Inhibition of the TGFB pathway in BE cell lines reduced the proliferation of dysplastic, but not nondysplastic, cells.
In a transcriptome analysis of EAC and nondysplastic BE tissues, we found the TGFB and JNK signaling pathways to be hyperactivated in EACs and the genes regulated by these pathways to be overexpressed in EAC and dysplastic BE. Inhibiting these pathways in EAC cells reduces their proliferation, migration, and formation of xenograft tumors. Strategies to block the TGFB and JNK signaling pathways might be developed for treatment of EAC.
食管腺癌（EAC）对标准放化疗具有耐药性，且可用的靶向治疗方法很少。我们使用大规模组织分析和遗传药理学分析来鉴定 EAC 组织中失调的信号通路，这些通路可能被用于减缓肿瘤生长或进展。
我们收集了 397 例 EAC 患者和非恶性 Barrett 食管（BE）患者的活检标本，包括有或无异型增生的患者。我们进行了 RNA 测序分析，并使用系统生物学方法鉴定 EAC 与非恶性异型增生组织之间差异激活的通路；通过免疫组织化学和定量实时聚合酶链反应分析患者组织样本中的信号通路成分，对通路活性进行了验证。用药理抑制剂孵育人 EAC（FLO-1 和 EsoAd1）、异型增生 BE（CP-B、CP-C、CP-D）和非异型增生 BE（CP-A）细胞，或用小干扰 RNA 转染。我们测量了这些抑制剂对裸鼠异种移植肿瘤生长的增殖、集落形成、迁移和/或生长的影响。
与非异型增生 BE 组织相比，EAC 组织的比较显示超过 80%的 EAC 样本中 TGFB 和/或 JNK 信号通路过度激活。免疫组织化学分析显示，与非恶性组织相比，EAC 肿瘤组织中磷酸化 JUN 和 SMAD 蛋白的核定位增加。受 TGFB 和 JNK 通路调节的基因在 EAC 和异型增生 BE 中特异性过表达。在 EAC 细胞（FLO-1 或 EsoAd1）中抑制 TGFB 或 JNK 信号通路成分，以 SMAD4 非依赖性方式显著降低细胞增殖、集落形成、细胞迁移和/或异种移植肿瘤在小鼠中的生长。在 BE 细胞系中抑制 TGFB 通路可降低异型增生细胞的增殖，但不降低非异型增生细胞的增殖。
在 EAC 和非异型增生 BE 组织的转录组分析中，我们发现 TGFB 和 JNK 信号通路在 EAC 中过度激活，这些通路调节的基因在 EAC 和异型增生 BE 中过表达。抑制 EAC 细胞中的这些通路可降低其增殖、迁移和异种移植肿瘤的形成。开发阻断 TGFB 和 JNK 信号通路的策略可能用于治疗 EAC。
