scholarly journals A Molecular Stratification of Chilean Gastric Cancer Patients with Potential Clinical Applicability

Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1863
Author(s):  
Mauricio P. Pinto ◽  
Miguel Córdova-Delgado ◽  
Ignacio N. Retamal ◽  
Matías Muñoz-Medel ◽  
M. Loreto Bravo ◽  
...  

Gastric cancer (GC) is a complex and heterogeneous disease. In recent decades, The Cancer Genome Atlas (TCGA) and the Asian Cancer Research Group (ACRG) defined GC molecular subtypes. Unfortunately, these systems require high-cost and complex techniques and consequently their impact in the clinic has remained limited. Additionally, most of these studies are based on European, Asian, or North American GC cohorts. Herein, we report a molecular classification of Chilean GC patients into five subtypes, based on immunohistochemical (IHC) and in situ hybridization (ISH) methods. These were Epstein–Barr virus positive (EBV+), mismatch repair-deficient (MMR-D), epithelial to mesenchymal transition (EMT)-like, and accumulated (p53+) or undetected p53 (p53−). Given its lower costs this system has the potential for clinical applicability. Our results confirm relevant molecular alterations previously reported by TCGA and ACRG. We confirm EBV+ and MMR-D patients had the best prognosis and could be candidates for immunotherapy. Conversely, EMT-like displayed the poorest prognosis; our data suggest FGFR2 or KRAS could serve as potential actionable targets for these patients. Finally, we propose a low-cost step-by-step stratification system for GC patients. To the best of our knowledge, this is the first Latin American report on a molecular classification for GC. Pending further validation, this stratification system could be implemented into the routine clinic

2017 ◽  
pp. 1-10 ◽  
Author(s):  
Tomohiro F. Nishijima ◽  
Jordan Kardos ◽  
Shengjie Chai ◽  
Christof C. Smith ◽  
Dante S. Bortone ◽  
...  

Purpose Claudin-low molecular subtypes have been identified in breast and bladder cancers and are characterized by low expression of claudins, enrichment for epithelial-to-mesenchymal transition (EMT), and tumor-initiating cell (TIC) features. We evaluated whether the claudin-low subtype also exists in gastric cancer. Materials and Methods Four hundred fifteen tumors from The Cancer Genome Atlas (TCGA) gastric cancer mRNA data set were clustered on the claudin, EMT, and TIC gene sets to identify claudin-low tumors. We derived a 24-gene predictor that classifies gastric cancer into claudin-low and non–claudin-low subtypes. This predictor was validated with the Asian Cancer Research Group (ACRG) data set. We characterized molecular and clinical features of claudin-low tumors. Results We identified 46 tumors that had consensus enrichment for claudin-low features in TCGA data set. Claudin-low tumors were most commonly diffuse histologic type (82%) and originally classified as TCGA genomically stable (GS) subtype (78%). Compared with GS subtype, claudin-low subtype had significant activation in Rho family of GTPases signaling, which appears to play a key role in its EMT and TIC properties. In the ACRG data set, 28 of 300 samples were classified as claudin-low tumors by the 24-gene predictor and were phenotypically similar to the initially derived claudin-low tumors. Clinically, claudin-low subtype had the worst overall survival. Of note, the hazard ratios that compared claudin-low versus GS subtype were 2.10 (95% CI, 1.07 to 4.11) in TCGA and 2.32 (95% CI, 1.18 to 4.55) in the ACRG cohorts, with adjustment for age and pathologic stage. Conclusion We identified a gastric claudin-low subtype that carries a poor prognosis likely related to therapeutic resistance as a result of its EMT and TIC phenotypes.


Cancers ◽  
2018 ◽  
Vol 10 (6) ◽  
pp. 167 ◽  
Author(s):  
Jun Nishikawa ◽  
Hisashi Iizasa ◽  
Hironori Yoshiyama ◽  
Kanami Shimokuri ◽  
Yuki Kobayashi ◽  
...  

Epstein–Barr virus-associated gastric carcinoma (EBVaGC) is the most common malignancy caused by EBV infection. EBVaGC has definite histological characteristics similar to gastric carcinoma with lymphoid stroma. Clinically, EBVaGC has a significantly low frequency of lymph node metastasis compared with EBV-negative gastric cancer, resulting in a better prognosis. The Cancer Genome Atlas of gastric adenocarcinomas proposed a molecular classification divided into four molecular subtypes: (1) EBVaGC; (2) microsatellite instability; (3) chromosomal instability; and (4) genomically stable tumors. EBVaGC harbors a DNA methylation phenotype, PD-L1 and PD-L2 overexpression, and frequent alterations in the PIK3CA gene. We review clinical importance of EBVaGC and discuss novel therapeutic applications for EBVaGC.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Adrian Murphy ◽  
Ronan J. Kelly

Histological classification of adenocarcinoma or squamous cell carcinoma for esophageal cancer or using the Lauren classification for intestinal and diffuse type gastric cancer has limited clinical utility in the management of advanced disease. Germline mutations in E-cadherin (CDH1) or mismatch repair genes (Lynch syndrome) were identified many years ago but given their rarity, the identification of these molecular alterations does not substantially impact treatment in the advanced setting. Recent molecular profiling studies of upper GI tumors have added to our knowledge of the underlying biology but have not led to an alternative classification system which can guide clinician’s therapeutic decisions. Recently the Cancer Genome Atlas Research Network has proposed four subtypes of gastric cancer dividing tumors into those positive for Epstein-Barr virus, microsatellite unstable tumors, genomically stable tumors, and tumors with chromosomal instability. Unfortunately to date, many phase III clinical trials involving molecularly targeted agents have failed to meet their survival endpoints due to their use in unselected populations. Future clinical trials should utilize molecular profiling of individual tumors in order to determine the optimal use of targeted therapies in preselected patients.


Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3722
Author(s):  
Till Daun ◽  
Ronny Nienhold ◽  
Aino Paasinen-Sohns ◽  
Angela Frank ◽  
Melanie Sachs ◽  
...  

Gastric adenocarcinoma (GAC) is a heterogeneous disease and at least two major studies have recently provided a molecular classification for this tumor: The Cancer Genome Atlas (TCGA) and the Asian Cancer Research Group (ARCG). Both classifications quote four molecular subtypes, but these subtypes only partially overlap. In addition, the classifications are based on complex and cost-intensive technologies, which are hardly feasible for everyday practice. Therefore, simplified approaches using immunohistochemistry (IHC), in situ hybridization (ISH) as well as commercially available next generation sequencing (NGS) have been considered for routine use. In the present study, we screened 115 GAC by IHC for p53, MutL Homolog 1 (MLH1) and E-cadherin and performed ISH for Epstein–Barr virus (EBV). In addition, sequencing by NGS for TP53 and tumor associated genes was performed. With this approach, we were able to define five subtypes of GAC: (1) Microsatellite Instable (MSI), (2) EBV-associated, (3) Epithelial Mesenchymal Transition (EMT)-like, (4) p53 aberrant tumors surrogating for chromosomal instability and (5) p53 proficient tumors surrogating for genomics stable cancers. Furthermore, by considering lymph node metastasis in the p53 aberrant GAC, a better prognostic stratification was achieved which finally allowed us to separate the GAC highly significant in a group with poor and good-to-intermediate prognosis, respectively. Our data show that molecular classification of GAC can be achieved by using commercially available assays including IHC, ISH and NGS. Furthermore, we present an integrative workflow, which has the potential to overcome the uncertainty resulting from discrepancies from existing classification schemes.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Wanting Song ◽  
Yi Bai ◽  
Jialin Zhu ◽  
Fanxin Zeng ◽  
Chunmeng Yang ◽  
...  

Abstract Background Gastric cancer (GC) represents a major malignancy and is the third deathliest cancer globally. Several lines of evidence indicate that the epithelial-mesenchymal transition (EMT) has a critical function in the development of gastric cancer. Although plentiful molecular biomarkers have been identified, a precise risk model is still necessary to help doctors determine patient prognosis in GC. Methods Gene expression data and clinical information for GC were acquired from The Cancer Genome Atlas (TCGA) database and 200 EMT-related genes (ERGs) from the Molecular Signatures Database (MSigDB). Then, ERGs correlated with patient prognosis in GC were assessed by univariable and multivariable Cox regression analyses. Next, a risk score formula was established for evaluating patient outcome in GC and validated by survival and ROC curves. In addition, Kaplan-Meier curves were generated to assess the associations of the clinicopathological data with prognosis. And a cohort from the Gene Expression Omnibus (GEO) database was used for validation. Results Six EMT-related genes, including CDH6, COL5A2, ITGAV, MATN3, PLOD2, and POSTN, were identified. Based on the risk model, GC patients were assigned to the high- and low-risk groups. The results revealed that the model had good performance in predicting patient prognosis in GC. Conclusions We constructed a prognosis risk model for GC. Then, we verified the performance of the model, which may help doctors predict patient prognosis.


Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 733
Author(s):  
Nobutaka Ebata ◽  
Masashi Fujita ◽  
Shota Sasagawa ◽  
Kazuhiro Maejima ◽  
Yuki Okawa ◽  
...  

Gallbladder cancer (GBC), a rare but lethal disease, is often diagnosed at advanced stages. So far, molecular characterization of GBC is insufficient, and a comprehensive molecular portrait is warranted to uncover new targets and classify GBC. We performed a transcriptome analysis of both coding and non-coding RNAs from 36 GBC fresh-frozen samples. The results were integrated with those of comprehensive mutation profiling based on whole-genome or exome sequencing. The clustering analysis of RNA-seq data facilitated the classification of GBCs into two subclasses, characterized by high or low expression levels of TME (tumor microenvironment) genes. A correlation was observed between gene expression and pathological immunostaining. TME-rich tumors showed significantly poor prognosis and higher recurrence rate than TME-poor tumors. TME-rich tumors showed overexpression of genes involved in epithelial-to-mesenchymal transition (EMT) and inflammation or immune suppression, which was validated by immunostaining. One non-coding RNA, miR125B1, exhibited elevated expression in stroma-rich tumors, and miR125B1 knockout in GBC cell lines decreased its invasion ability and altered the EMT pathway. Mutation profiles revealed TP53 (47%) as the most commonly mutated gene, followed by ELF3 (13%) and ARID1A (11%). Mutations of ARID1A, ERBB3, and the genes related to the TGF-β signaling pathway were enriched in TME-rich tumors. This comprehensive analysis demonstrated that TME, EMT, and TGF-β pathway alterations are the main drivers of GBC and provides a new classification of GBCs that may be useful for therapeutic decision-making.


2020 ◽  
Vol 5 (1) ◽  
pp. 11-14
Author(s):  
Seyed Mohammad Azizi ◽  
Mehrdad Hashemi ◽  
Sarvenaz Falsafi ◽  
Seyedeh Mina Azizi ◽  
Reza Shirkoohi

Aim and Background: Gastric cancer is the fourth most common cancer in the world and the second leading cause of cancer-related deaths. The metastatic invasive cells of tumor tissue are the main cause of mortality. Numerous biological phenomena are involved in organizing the metastatic process. The Epithelial to Mesenchymal Transition is one of the major mechanisms modulating malignant phenotypes by gastric epithelial cells. Specific cell signals are responsible for epithelial or mesenchymal maintenance of the cells in the tissue. These signals are evaluated by measuring the expression of epithelial and mesenchymal biomarkers in that tissue. Villin is an actin-binding protein mainly expressed in the brush border of epithelium which preserves the shape of the cell and its adhesion to the tissue. The aim of the present research is to study the expression of Villin in the cells as a feasible epithelial biomarker in order to evaluate the cross-sectional situation of the cells. Materials and Methods: 38 patients with gastric cancer that were admitted to the Cancer Institute of Imam Khomeini in a period of 6 months were chosen randomly. two samples were collected from each individual; one from the tumoral tissue and one from normal margin of the tumorous tissue. These samples were evaluated after obtaining informed consent from the patients. RNA was extracted from the samples and used as template for cDNA synthesis. The Villin expression was then measured through Real-Time PCR and statistical data according to tissue type and different grades were collected. Results: The expression of Villin in tumor tissue of the patients with gastric cancer was significantly lower than the normal tissue. Conclusion: As it appears decreased expression of Villin can act as an effective factor toward loss of epithelial nature of the cell and occurring Epithelial to Mesenchymal Transition followed by metastasis.


2019 ◽  
Author(s):  
Hongyu Gao ◽  
Ling Qin ◽  
Huawen Shi ◽  
Hongfeng Zhang ◽  
Chunfeng Li ◽  
...  

Abstract Background: Although ArfGAP with SH3 Domain, Ankyrin Repeat and PH Domain 1(ASAP1) is involved in the development of various malignancies, its clinical significance and mechanism in gastric cancer (GC) remains unclear.Methods: The effects of ASAP1 on tumor progression, angiogenesis, and epithelial-mesenchymal transition were evaluated in vitro. The effects of ASAP1 on tumor growth and angiogenesis were also explored in vivo. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were used to gather ASAP1 expression data.Results: It showed that ASAP1 expression strongly correlated with the TNM stage (P < 0.0001) and lymph node metastasis (P < 0.0001). Multivariate analyses indicated that ASAP1 overexpression (P < 0.0001) was an independent predictor for overall survival in patients with GC. Moreover, the results revealed that ASAP1 overexpression was independently related to lymph node metastasis (P = 0.0001). ASAP1 knockdown inhibited tumor cell motility, migration, invasion, and angiogenesis, which was accompanied with the downregulation of metastatic and angiogenic biomarkers. Furthermore, ASAP1 inhibition resulted in the simultaneous downregulation of mesenchymal markers and upregulation of epithelial markers. In addition, ASAP1 promoted tumor growth and angiogenesis in the xenograft mice model. The combined datasets (TCGA and GEO) suggested that ASAP1 was associated with malignant behavior of tumor and tumor invasion, metastasis, and angiogenesis.Conclusion: To our knowledge, our study is the first to reveal that ASAP1 promotes tumor progression and angiogenesis, and indicates a prognostic potential in GCs.


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