Esophageal cancer

G2 and S phase-expressed-1 induces chromosomal instability in esophageal squamous cell carcinoma cells and inhibits cell apoptosis through ROS/JNK signaling

New diagnostic and therapeutic strategies are urgently needed to improve the prognosis of patients with esophageal squamous cell carcinoma (ESCC), which has high morbidity and mortality. Bioinformatics analysis revealed that cell cycle regulation related molecular G2 and S phase-expressed-1 (GTSE1) was dysregulated in ESCC. In this study, the ectopic expression of GTSE1 was verified in ESCC patients' tissues and cell lines. After overexpression or knockdown of GTSE1 using lentiviral transfection, the effects of GTSE1 on the proliferation, migration, invasion, and apoptosis of ESCC cells were detected. The contribution of GTSE1 in inducing chromosomal missegregation in cells leading to chromosome instability (CIN) has been described. Long-term existence of CIN can increase reactive oxygen species (ROS) generation in ESCC cells, followed by inhibition of apoptosis by activating the c-Jun N-terminal kinase (JNK) signaling pathway, and this inhibition could be relieved after treatment with JNK inhibitor. In vivo experiments, we also confirmed the tumor-promoting effect and mechanism of GTSE1 in ESCC using nude mice model. In this study, we demonstrated that GTSE1 induces CIN in ESCC cells, and increases intracellular ROS production, which leads to cellular oxidative stress, contributes to the activation of the JNK signaling pathway, and thereby inhibits apoptosis leading to ESCC tumorigenesis.

Aspirin Exerts Its Antitumor Effect in Esophageal Squamous Cell Carcinoma by Downregulating the Expression of ATAD2 and KIF4A

Objective

To investigate the expression of ATPase family AAA domain-containing protein 2 (ATAD2) and kinesin family member 4A (KIF4A) in esophageal squamous cell carcinoma (ESCC) tissues and their association with clinicopathological features and to explore the role of ATAD2 in regulating KIF4A expression and biological functions in ESCC cells and the effect of aspirin on their expression.

Methods

The mRNA and protein expression of ATAD2 and KIF4A in the tissues of patients with ESCC were measured by RT-qPCR and immunohistochemistry, and the correlation between the expression of mRNA and clinicopathological characteristics was analyzed. Western blot and RT-qPCR were used to detect the interference efficiency and KIF4A expression after si-ATAD2 transfection in EC109 and KYSE30 cells. CCK-8 and Transwell assay were performed to investigate the effects of ATAD2 and aspirin on proliferation, migration, and invasion of ESCC cells. The effect of aspirin on the expression of ATAD2 and KIF4A in ESCC cells was measured by RT-qPCR and Western blot.

Results

The expression of ATAD2 and KIF4A was upregulated in ESCC tissues, and both were correlated with the differentiation grades and lymph node metastasis. Knockdown of ATAD2 in ESCC cells significantly inhibited cell proliferation, migration, and invasion. Compared to the negative control group, the proliferation, migration, and invasion ability of ESCC cells in the aspirin-treated groups were decreased, and the expression of ATAD2 and KIF4A in ESCC cells was decreased after treating with aspirin for 48 h.

Conclusion

The expression levels of ATAD2 and KIF4A are elevated in ESCC. ATAD2 promotes proliferation, migration, and invasion of ESCC cells by regulating KIF4A. Aspirin can inhibit the malignant behavior of ESCC cells by downregulating ATAD2 and KIF4A.

History of the Use of Esophageal Stent in Management of Dysphagia and Its Improvement Over the Years

The art and science of using stents to treat dysphagia and seal fistula, leaks and perforations has been evolving. Lessons learnt from the deficiencies of previous models led to several improvements making stent deployment easier, and with some designs, it was also possible to remove the stents if needed. With these improvements, besides malignant dysphagia, newer indications for using stents emerged. Unfortunately, despite several decades of evolution, as yet, there is no perfect stent that "fits all." This article is an overview of how this evolution process happened and where we are currently with using stents to manage patients with dysphagia and with other esophageal disorders.

Discovery of stage-related proteins in esophageal squamous cell carcinoma using proteomic analysis

Esophageal squamous cell carcinoma (ESCC) is the major subtype of esophageal cancers in China, and characterized with high morbidity and mortality. So far, the diagnosis of ESCC is mainly dependent on the alterations in esophageal histology, but most cases of ESCC with low stage do not display visible histological abnormalities. Therefore, a deep understanding of the mechanism of ESCC progression and seeking stage-specific molecules might improve the diagnosis and therapy for ESCC. In this study, we used proteomics to analyze ESCC tissues with classification by TNM stage, and determined the proteomic features correlated with ESCC progression (from stages I to III). Proteins that exhibited significantly different expression patterns between ESCC and corresponding normal esophageal tissues were identified using MS. The identified proteins with differentiated expression mainly fell into three protein categories (i.e. cytoskeleton system-associated proteins, metabolism enzymes, and heat shock proteins). In addition, real-time PCR highlighted some molecules that were associated with tumor stages at the mRNA level, such as enolase 1, chromosome 1 ORF 10, elastase inhibitor, α B crystalline, stress-induced phosphoprotein 1, and squamous cell carcinoma antigen 1. Altogether, these data provided further information on ESCC progression and potential drug targets for ESCC clinical therapy.

An Auxetic structure configured as oesophageal stent with potential to be used for palliative treatment of oesophageal cancer; development and in vitro mechanical analysis

Oesophageal cancer is the ninth leading cause of malignant cancer death and its prognosis remains poor. Dysphagia which is an inability to swallow is a presenting symptom of oesophageal cancer and is indicative of incurability. The goal of this study was to design and manufacture an Auxetic structure film and to configure this film as an Auxetic stent for the palliative treatment of oesophageal cancer, and for the prevention of dysphagia. Polypropylene was used as a material for its flexibility and non-toxicity. The Auxetic (rotating-square geometry) structure was made by laser cutting the polypropylene film. This flat structure was welded together to form a tubular form (stent), by an adjustable temperature control soldering iron station: following this, an annealing process was also carried out to ease any material stresses. Poisson's ratio was estimated and elastic and plastic deformation of the Auxetic structure was evaluated. The elastic and plastic deformation behaviours of the Auxetic polypropylene film were evaluated by applying repetitive uniaxial tensile loads. Observation of the structure showed that it was initially elastically deformed, thereafter plastic deformation occurred. This research discusses a novel way of fabricating an Auxetic structure (rotating-squares connected together through hinges) on Polypropylene films, by estimating the Poisson's ratio and evaluating the plastic deformation relevant to the expansion behaviour of an Auxetic stent within the oesophageal lumen.

Transcriptional factor Prox1 plays an essential role in the antiproliferative action of interferon-γ in esophageal cancer cells

BACKGROUND

We previously reported interferon-γ (IFN-γ)-induced apoptosis in 10 (32%) of 31 esophageal squamous cell carcinoma (ESCC) cell lines. However, the molecular basis of antiproliferative action by IFN-γ remains elusive. Here we demonstrate that IFN-γ induces transcriptional factor Prox1, and we explore the link between Prox1 and the IFN-γ system in ESCC cells.

METHODS

By using ESCC cell lines, we investigated the relationship between p53 mutations and the responsibility to IFN-γ, and studied the role of Prox1 in the antiproliferative effect of IFN-γ by knockdown and overexpression methods.

RESULTS

p53 mutations were found in seven of nine ESCC cell lines responsible for IFN-γ. The frequency was not different from that of p53 mutations in total ESCC cell lines (21 of 28 cell lines). Treatment of ESCC cells with IFN-β but not IFN-γ resulted in increase of p53 messenger RNA (mRNA) expression, whereas IFN-γ but not IFN-β induced cell growth inhibition of ESCCs harboring p53 mutations. IFN-γ induced Prox1 expression in ESCC cells but not in those transfected with dominant-negative STAT1. Cell growth inhibition by IFN-γ was significantly suppressed in ESCC cells transfected with Prox1 short interfering RNA (siRNA). In addition, overexpression of Prox1 induced antiproliferative effect in ESCC cells. We also demonstrate that Prox1 is expressed in primary esophageal cancer tissues (five of nine samples treated with neoadjuvant chemotherapy before surgery).

CONCLUSIONS

Prox1 mediates the antiproliferative effect by IFN-γ in ESCC cells. Prox1 may be a candidate target for novel therapeutic strategies of ESCCs.

A combined proteomics and metabolomics profiling of gastric cardia cancer reveals characteristic dysregulations in glucose metabolism

Gastric cardia cancer (GCC), which occurs at the gastric-esophageal boundary, is one of the most malignant tumors. Despite its high mortality and morbidity, the molecular mechanism of initiation and progression of this disease is largely unknown. In this study, using proteomics and metabolomics approaches, we found that the level of several enzymes and their related metabolic intermediates involved in glucose metabolism were deregulated in GCC. Among these enzymes, two subunits controlling pyruvic acid efflux, lactate dehydrogenase A (LDHA) and pyruvate dehydrogenase B (PDHB), were further analyzed in vitro. Either down-regulation of LDH subunit LDHA or overexpression of PDH subunit PDHB could force pyruvic acid into the Krebs cycle rather than the glycolysis process in AGS gastric cancer cells, which inhibited cell growth and cell migration. Our results reflect an important glucose metabolic signature, especially the dysregulation of pyruvic acid efflux in the development of GCC. Forced transition from glycolysis to the Krebs cycle had an inhibitory effect on GCC progression, providing potential therapeutic targets for this disease.

[Risk factors for esophageal cancer, and possible genetic background]

Esophageal cancer is the sixth most common cancer mortality, with increasing incidence. 95% of the esophageal cancer is squamous cell carcinoma or adenocarcinoma. Although they differ in histology and epidemiology, some of their risk factors (smoking, dietary factors) and their pathogenesis are the same. More than 90% of esophageal cancer is diagnosed in late stage. Despite the development of diagnostic and therapeutic techniques, esophageal cancer has poor prognosis, with 5-year survival rates between 10-13%. Understanding the exact pathogenesis can help the prevention of this highly aggressive cancer, with the use of natural substances and nonsteroid inflammatory drugs.

Negative feedback regulation of IFN-gamma pathway by IFN regulatory factor 2 in esophageal cancers

IFN-gamma is an antitumor cytokine that inhibits cell proliferation and induces apoptosis after engagement with the IFN-gamma receptors (IFNGR) expressed on target cells, whereas IFN regulatory factor 2 (IRF-2) is able to block the effects of IFN-gamma by repressing transcription of IFN-gamma-induced genes. Thus far, few studies have explored the influences of IFN-gamma on human esophageal cancer cells. In the present study, therefore, we investigated in detail the functions of IFN-gamma in esophageal cancer cells. The results in clinical samples of human esophageal cancers showed that the level of IFN-gamma was increased in tumor tissues and positively correlated with tumor progression and IRF-2 expression, whereas the level of IFNGR1 was decreased and negatively correlated with tumor progression and IRF-2 expression. Consistently, in vitro experiments showed that low concentration of IFN-gamma induced the expression of IRF-2 with potential promotion of cell growth, and moreover, IRF-2 was able to suppress IFNGR1 transcription in human esophageal cancer cells by binding a specific motif in IFNGR1 promoter, which lowered the sensitivity of esophageal cancer cells to IFN-gamma. Taken together, our results disclosed a new IRF-2-mediated inhibitory mechanism for IFN-gamma-induced pathway in esophageal cancer cells: IFN-gamma induced IRF-2 up-regulation, then up-regulated IRF-2 decreased endogenous IFNGR1 level, and finally, the loss of IFNGR1 turned to enhance the resistance of esophageal cancer cells to IFN-gamma. Accordingly, the results implied that IRF-2 might act as a mediator for the functions of IFN-gamma and IFNGR1 in human esophageal cancers.

Genetic background of esophageal squamous cell carcinoma

A nyelőcsőrák a kilencedik leggyakoribb rosszindulatú daganat. Több mint 90%-ban előrehaladott állapotban kerül felismerésre. A sebészi beavatkozás, a kemo-, illetve radioterápia lehetőségei korlátozottak. Napjainkban a génterápia került az érdeklődés előterébe. A szerzők a nyelőcsőlaphámrák genetikai és molekuláris hátterét és a génterápiával elért kezdeti tapasztalatokat tekintik át. Ismertetik a komplementer nukleinsavak (antisense terápia), a génpótlás, a kis interferáló RNS-k alkalmazásának lehetőségeit.