Prognostic Significance of Expression of the Epithelial-Mesenchymal Transition-Related Factor Brachyury in Intrathoracic Lymphatic Spread of Non-Small Cell Lung Cancer

Design of an In Vitro Model for Epithelial-to-Mesenchymal Transition in Gastric Cancer

Epithelial-to-mesenchymal transition (EMT) is a developmental program that plays a vital role in gastric cancer, including aspects of tumor progression, the metastatic process, and resistance to treatment. Here, we have designed an in vitro model that mimics the features of EMT as observed in gastric cancer. The results showed that both migration and invasion were enhanced in gastric cancer cells with Brachyury overexpression. Additionally, the expression of IL-8 increased, while IL-8RA and IL-8RB levels significantly decreased in the in vitro model. Overall, the in vitro model offers an opportunity to study these phenomena relevant to EMT as they may occur in vivo in gastric cancer, as well as potential drug interactions that could interfere with these processes.

Activation of Wnt Pathway Suppresses Growth of MUG-Chor1 Chordoma Cell Line

Chordoma as a malignant bone tumor, occurs along the axial skeleton and does not have an effective therapy. Brachyury, which is a crucial player for the formation of early embryonic notochord, is abundantly found in both sporadic and familial chordoma. During embryonic development, Brachyury expression was reported to be regulated by the Wnt pathway. The objective of the study is to investigate the role of Wnt signaling in a human chordoma cell line in terms of proliferation, survival, and invasiveness. We tried to elucidate the signaling events that regulate Chordoma cancer. In this regard, Wnt pathway was activated or inhibited using various strategies including small molecules, siRNA-based knockdown and overexpression applications. The results indicated the negative regulatory effect of Wnt signaling activity on proliferation and migration capacity of the chordoma cells. It was revealed that when GSK3β was inhibited, the Wnt pathway was activated and negatively regulated T/Bra expression. Activity of the Wnt pathway caused cell cycle arrest, reduced migration potential of the cells, and led to cell death. Therefore, the present study suggests that the Wnt pathway plays a key role in suppressing the proliferation and invasive characteristics of human chordoma cells and has a great potential as a therapeutic target in further clinical studies.

Emerging target discovery and drug repurposing opportunities in chordoma

The development of effective and personalized treatment options for patients with rare cancers like chordoma is hampered by numerous challenges. Biomarker-guided repurposing of therapies approved in other indications remains the fastest path to redefining the treatment paradigm, but chordoma's low mutation burden limits the impact of genomics in target discovery and precision oncology efforts. As our knowledge of oncogenic mechanisms across various malignancies has matured, it's become increasingly clear that numerous properties of tumors transcend their genomes - leading to new and uncharted frontiers of therapeutic opportunity. In this review, we discuss how the implementation of cutting-edge tools and approaches is opening new windows into chordoma's vulnerabilities. We also note how a convergence of emerging observations in chordoma and other cancers is leading to the identification and evaluation of new therapeutic hypotheses for this rare cancer.

FGFR1/MAPK-directed brachyury activation drives PD-L1-mediated immune evasion to promote lung cancer progression

Immune checkpoint inhibitors provide promising benefits for patients with cancer. However, efficacy has been encumbered by high resistance rates. It is critical to understand the basic mechanisms of tumor-mediated resistance to this treatment modality. Previous studies have found that the transcription factor brachyury is highly expressed in lung cancer. Here, we show that brachyury activation induces the upregulation of PD-L1 leading to inactivation of T cell proliferation in vitro and inhibited infiltration of CD8⁺ and CD3⁺ T cells into tumor in an immunocompetent mouse model. We further demonstrate that FGFR1/MAPK activation regulates brachyury and PD-L1 expressions and promotes immunosuppression. Blocking FGFR1/MAPK suppresses brachyury and PD-L1 expressions, revives immune activity, and reverses the resistance to anti-PD-1 treatment to produce a durable therapeutic response. We also find that lung cancer patients with high activation of the FGFR1-MAPK-brachyury-PD-L1 signature and low expression of CD8A, CD3D, or PDCD1 have worse survival outcomes. These findings elucidate a novel mechanism of immune escape from immune checkpoint therapy and provide an opportunity to enhance its therapeutic efficacy in the treatment of a subset of FGFR1/MAPK/brachyury/PD-L1-driven lung cancer.

The Roles of Embryonic Transcription Factor BRACHYURY in Tumorigenesis and Progression

Transcription factor brachyury, with a DNA-binding T-domain, regulates posterior mesoderm formation and notochord development through binding with highly conserved palindromic consensus sequence in a variety of organisms. The absence of brachyury expression in majority of adult normal tissues and exclusive tumor-specific expression provides the potential to be developed into a novel and promising diagnostic and therapeutic target in cancer. As a sensitive and specific marker in the diagnosis of chordoma, brachyury protein has been verified to involve in the process of carcinogenesis and progression of chordoma and several epithelial carcinomas in various studies, but the mechanism by which brachyury promotes tumor cells migrate, invade and metastasis still remains less clear. To this end, we attempt to summarize the literature on the upstream regulatory pathway of brachyury transcription and downstream controlling network by brachyury activation, all of which involve in both the embryonic development and tumor progression. We present the respective correlation of brachyury expression with tumor progression, distant metastasis, survival rate and prognosis in several types of tumor samples (including chordoma, lung cancer, breast carcinoma, and prostate cancer), and various brachyury gain-of-function and loss-of-function experiments are summarized to explore its specific role in respective tumor cell line in vitro. In addition, we also discuss another two programs relating to brachyury function: epithelial-to-mesenchymal transition (EMT) and cell cycle control, both of which implicate in the regulation of brachyury on biological behavior of tumor cells. This review will provide an overview of the function of master transcriptional factor brachyury, compare the similarities and differences of its role between embryonic development and carcinogenesis, and list the evidence on which brachyury-target therapies have the potential to help control advanced cancer populations.

Prognostic significance of expression of epithelial-mesenchymal transition driver brachyury in breast cancer and its association with subtype and characteristics

Brachyury is a T-box transcription factor characterized as a driver of the epithelial-to-mesenchymal process, which is associated with poor prognosis of patients with breast cancer. The present study investigated expression of brachyury in breast cancer including primary tumor, metastatic and recurred tumor tissues, and the clinical significance and value of brachyury as a prognostic biomarker. This retrospective study included a series of 102 consecutive patients surgically resected between January 2005 and December 2011. Brachyury expression in tumor cell was evaluated using immunohistochemistry and scored as the immunoactivity. Of 102 patients, 62 primary tumors were positive for brachyury expression and 40 were negative. Multivariate analysis of disease-free survival (DFS) revealed brachyury expression, HER2 and lymphovascular invasion as independent prognostic factors [brachyury negative vs. positive hazard ratio (HR), 3.0; P=0.024; HER2 negative vs. positive HR, 4.9; P=0.003; lymphovascular invasion absent vs. present HR, 3.5; P=0.020]. These results were particularly observed in triple-negative breast cancer (TNBC), no recurrence or mortality occurred in brachyury negative group during the follow-up period, and therefore a significantly improved prognosis was demonstrated in these patients compared with the brachyury positive group [overall survival (OS), P=0.022; DFS, P=0.002]. Brachyury expression in metastatic lymph node/recurred tumors was not significantly associated with prognosis (OS, P=0.745; DFS, P=0.189). Therefore, Brachyury expression in primary tumor independently is a potential predictor of poor prognosis, particularly in TNBC, where it appears to serve a crucial function in recurrence and mortality. Brachyury vaccines under clinical trials are likely to be useful in patients with breast cancer.

Role and underlying mechanisms of the interstitial protein periostin in the diagnosis and treatment of malignant tumors

Invasion and metastasis are the major characteristics of malignant tumors and are complex processes involving multiple genes. Gene regulation is a precise, large and complex biological control system, and its underlying mechanisms remain to be elucidated. Mesenchymal-specific genes are expressed primarily by mesenchymal cells, and the expression products of these genes are molecules with various structures and functions, including secreted proteins and extracellular matrix proteins. The periostin gene has been newly identified as a mesenchymal-specific gene and an extracellular-matrix secreted protein. Periostin is able to bind to various subtypes of integrin receptors on the surface of the cell membrane. This triggers relevant signal transduction pathways to alter the microenvironment of cancer cells in order to facilitate their survival, invasion, metastasis and angiogenesis as well as enhance the tolerance to hypoxia and chemicals. Therefore, periostin is associated with the grade of malignancy, level of invasion and prognosis of malignant tumors. The in-depth study of periostin may provide an effective marker for tumor diagnosis and prognosis, as well as a novel treatment target.

Epithelial-to-Mesenchymal Transition and MicroRNAs in Lung Cancer

Despite major advances, non-small cell lung cancer (NSCLC) remains the major cause of cancer-related death in developed countries. Metastasis and drug resistance are the main factors contributing to relapse and death. Epithelial-to-mesenchymal transition (EMT) is a complex molecular and cellular process involved in tissue remodelling that was extensively studied as an actor of tumour progression, metastasis and drug resistance in many cancer types and in lung cancers. Here we described with an emphasis on NSCLC how the changes in signalling pathways, transcription factors expression or microRNAs that occur in cancer promote EMT. Understanding the biology of EMT will help to define reversing process and treatment strategies. We will see that this complex mechanism is related to inflammation, cell mobility and stem cell features and that it is a dynamic process. The existence of intermediate phenotypes and tumour heterogeneity may be debated in the literature concerning EMT markers, EMT signatures and clinical consequences in NSCLC. However, given the role of EMT in metastasis and in drug resistance the development of EMT inhibitors is an interesting approach to counteract tumour progression and drug resistance. This review describes EMT involvement in cancer with an emphasis on NSCLC and microRNA regulation.