ly-2157299 and Esophageal-Neoplasms

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.

Topics: Adenocarcinoma; Animals; Barrett Esophagus; Benzamides; Cell Line, Tumor; Cell Movement; Cell Proliferation; Dioxoles; Esophageal Neoplasms; Female; Gene Expression Regulation, Neoplastic; Humans; Male; MAP Kinase Signaling System; Mice; Neoplasm Transplantation; Oligonucleotide Array Sequence Analysis; Pharmacogenomic Testing; Proto-Oncogene Proteins c-jun; Pyrazoles; Quinolines; Receptors, Transforming Growth Factor beta; RNA, Neoplasm; Smad Proteins; Systems Biology; Transcriptome; Transforming Growth Factor beta; Tumor Stem Cell Assay

Previous studies on the mechanisms underlying ESCC (esophageal squamous cell carcinoma) chemoresistance only focused on tumor cells while tumor microenvironment has been completely ignored. Our study aimed to clarify the effect of CAFs (cancer-associated fibroblasts), one major component of tumor microenvironment, on the chemoresistance of ESCC. By primary culture, two pairs of CAFs and matched NFs (normal fibroblasts) were isolated from tumor tissues of ESCC patients and matched normal esophageal epithelial tissues, respectively. The association of CAFs and chemoresistance was assessed in esophageal carcinoma cells, in xenograft tumor models and in clinical specimens of ESCC patients. We found CAFs conferred ESCC cells significant resistance to several common chemotherapeutic drugs including cisplatin, taxol, irinotecan (CPT-11), 5-fluorouracil (5-Fu), carboplatin, docetaxel, pharmorubicin, and vincristine. Mechanism studies revealed that blockage of CAFs-secreted TGFβ1 signaling by its receptor TGFβR1 inhibitor LY2157299 significantly reversed the chemoresistance in vitro and in vivo. Furthermore, the crosstalk of CAFs and ESCC cells enhanced the expression and activation of FOXO1, a member of the forkhead transcription factors in the O-box sub-family, inducing TGFβ1 expression in an autocrine/paracrine signaling loop. In 130 ESCC patients, the expression of TGFβ1 in CAFs was significantly associated with overall survival of patients treated with chemoradiotherapy. Together, our study highlighted TGFβ1 expressed in CAFs as an attractive target to reverse tumor chemoresistance, and can be used as an independent prognostic factor of ESCC patients treated with chemoradiotherapy. © 2016 Wiley Periodicals, Inc.

Topics: Adult; Aged; Animals; Antineoplastic Agents; Cancer-Associated Fibroblasts; Carcinoma, Squamous Cell; Cell Communication; Drug Resistance, Neoplasm; Esophageal Neoplasms; Esophageal Squamous Cell Carcinoma; Female; Forkhead Box Protein O1; Gene Expression Regulation, Neoplastic; Humans; Male; Mice; Middle Aged; Pyrazoles; Quinolines; Signal Transduction; Survival Analysis; Transforming Growth Factor beta1; Tumor Microenvironment; Xenograft Model Antitumor Assays