Preclinical tumor mouse models for studying esophageal cancer.

Preclinical models are extensively employed in cancer research because they can be manipulated in terms of their environment, genome, molecular biology, organ systems, and physical activity to mimic human behavior and conditions. The progress made in in vivo cancer research has resulted in significant advancements, enabling the creation of spontaneous, metastatic, and humanized mouse models. Most recently, the remarkable and extensive developments in genetic engineering, particularly the utilization of CRISPR/Cas9, transposable elements, epigenome modifications, and liquid biopsies, have further facilitated the design and development of numerous mouse models for studying cancer. In this review, we have elucidated the production and usage of current mouse models, such as xenografts, chemical-induced models, and genetically engineered mouse models (GEMMs), for studying esophageal cancer. Additionally, we have briefly discussed various gene-editing tools that could potentially be employed in the future to create mouse models specifically for esophageal cancer research.

Whole Exome Sequencing Reveals a Novel Damaging Mutation in Human Fibroblast Activation Protein in a Family with Esophageal Squamous Cell Carcinoma.

PURPOSE: Esophageal squamous cancer cell (ESCC), with late diagnosis and poor rate of survival, is a significant cause of mortality in the developing countries. The hypothesis of rare high penetrance with mutations in new genes may explain the underlying predisposition in some of these familial cases. METHODS: Exome sequencing was performed in the patients with ESCC with strong disease aggregation, two sisters with ESCC cancer, and one with breast cancer. Data analysis selected only very rare variants (0-0.1%) located in genes with a role compatible with cancer. In addition, the homology modeling of the novel mutation (A459D) discovered in FAP gene was performed by using the online Swiss-Prot server for automated modeling and the resulted structure has been modified and analyzed by using bioinformatics software to thoroughly study the structural deficiencies caused by the novel mutation. RESULTS: Ten final candidate variants were selected and six genes validated by Sanger sequencing. Correct family segregation and somatic studies were used to categorize the most interesting variants in FAP, BOD1L, RAD51, Gasdermin D, LGR5, and CERS4. A novel, human mutation C1367A encoding Ala459 Asp (accession number: KT988039), occurring in the blade of the ß propeller domain, was identified in two sisters with ESCC. CONCLUSIONS: We identified novel mutations in three drug delivery genes, a tumor suppressor and also a stem cell marker of esophageal that may have a role in cancer treatment and are involved in cellular pathways, which supports their putative involvement in germ-line predisposition to this neoplasm.

TWIST1, MMP-21, and HLAG-1 co-overexpression is associated with ESCC aggressiveness.

Esophageal squamous cell carcinoma (ESCC) is one of the most aggressive types of cancer, requiring reliable biomarkers for prognosis and therapeutic responsiveness. TWIST1, as an important factor responsible for metastasis of several cancers, is involved in tumor invasion and metastasis through indirectly regulation of MMP-21 expression. On the other hand, NF-Ä¸ß which is a regulator of HLAG-1 has direct interaction with TWIST1 protein. In this retrospective study we investigated the clinical significance of TWIST1, MMP-21, and HLAG-1 expression in ESCC, and the possible correlation between these genes and progression of the disease. The gene expression analyses of TWIST1, MMP-21, and HLA-G1 were performed by relative comparative real-time polymerase chain reaction in 58 ESCCs compared with corresponding margin-normal esophageal tissues. Significant overexpression of HLAG-1, TWIST1, and MMP-21 messenger RNA was observed in 22.4%, 41.4%, and 60.3% of tumor samples, respectively. Concomitant overexpression of TWIST1/MMP-21 and TWIST1/HLAG-1 were significantly correlated to each other in various clinicopathological features, including depth of tumor invasion, stage of tumor progression, lymphatic invasion, and grade of tumor cell differentiation ( P < 0.05). The current study is the first report of coexpression of TWIST1, MMP-21, and HLAG-1 in ESCC. Such findings suggest an oncogenic role for concomitant expression of these genes in ESCC invasion and metastasis.

Novel mutations and their genotype-phenotype correlations in patients with Noonan syndrome, using next-generation sequencing.

PURPOSE: Noonan Syndrome (NS) is an autosomal dominant disorder with many variable and heterogeneous conditions. The genetic basis for 20-30% of cases is still unknown. This study evaluates Iranian Noonan patients both clinically and genetically for the first time. MATERIALS/METHODS: Mutational analysis of PTPN11 gene was performed in 15 Iranian patients, using PCR and Sanger sequencing at phase one. Then, as phase two, Next Generation Sequencing (NGS) in the form of targeted resequencing was utilized for analysis of exons from other related genes. Homology modelling for the novel founded mutations was performed as well. The genotype, phenotype correlation was done according to the molecular findings and clinical features. RESULTS: Previously reported mutation (p.N308D) in some patients and a novel mutation (p.D155N) in one of the patients were identified in phase one. After applying NGS methods, known and new variants were found in four patients in other genes, including: CBL (p. V904I), KRAS (p. L53W), SOS1 (p. I1302V), and SOS1 (p. R552G). Structural studies of two deduced novel mutations in related genes revealed deficiencies in the mutated proteins. Following genotype, phenotype correlation, a new pattern of the presence of intellectual disability in two patients was registered. CONCLUSIONS: NS shows strong variable expressivity along the high genetic heterogeneity especially in distinct populations and ethnic groups. Also possibly unknown other causative genes may be exist. Obviously, more comprehensive and new technologies like NGS methods are the best choice for detection of molecular defects in patients for genotype, phenotype correlation and disease management.