Clinical application of malignancy potential grading as a prognostic factor of human esophageal cancers

The Role of the Heat-Shock Proteins in Esophagogastric Cancer

Heat-shock proteins (HSPs) are a family of proteins that have received considerable attention over the last several years. They have been classified into six prominent families: high-molecular-mass HSP, 90, 70, 60, 40, and small heat shock proteins. HSPs participate in protein folding, stability, and maturation of several proteins during stress, such as in heat, oxidative stress, fever, and inflammation. Due to the immunogenic host's role in the combat against cancer cells and the role of the inflammation in the cancer control or progression, abnormal expression of these proteins has been associated with many types of cancer, including esophagogastric cancer. This study aims to review all the evidence concerning the role of HSPs in the pathogenesis and prognosis of esophagogastric cancer and their potential role in future treatment options. This narrative review gathers scientific evidence concerning HSPs in relation to esophagus and gastric cancer. All esophagogastric cancer subtypes are included. The role of HSPs in carcinogenesis, prognostication, and therapy for esophagogastric cancer are discussed. The main topics covered are premalignant conditions for gastric cancer atrophic gastritis, Barrett esophagus, and some viral infections such as human papillomavirus (HPV) and Epstein-Barr virus (EBV). HSPs represent new perspectives on the development, prognostication, and treatment of esophagogastric cancer.

Revisiting the Old Data of Heat Shock Protein 27 Expression in Squamous Cell Carcinoma: Enigmatic HSP27, More Than Heat Shock

Initially discovered to be induced by heat shock, heat shock protein 27 (HSP27, also called HSPB1), a member of the small HSP family, can help cells better withstand or avoid heat shock damage. After years of studies, HSP27 was gradually found to be extensively engaged in various physiological or pathophysiological activities. Herein, revisiting the previously published data concerning HSP27, we conducted a critical review of the literature regarding its role in squamous cell carcinoma (SCC) from the perspective of clinicopathological and prognostic significance, excluding studies conducted on adenocarcinoma, which is very different from SCC, to understand the enigmatic role of HSP27 in the tumorigenesis of SCC, including normal mucosa, dysplasia, intraepithelial neoplasm, carcinoma in situ and invasive SCC.

Relationship between the immunohistological examination and fluorescence visualization of oral squamous cell carcinoma

Disorders of the oral mucosa are considered easy to diagnose since they can be visualized and examined directly. A change in the color of the oral mucosa reflects histopathological changes and is an important diagnostic parameter. However, the subjective perception of color varies. To determine the extent of resection for oral mucosa conditions, it is necessary to digitize the color and perform objective assessments. In recent years, fluorescence visualization devices and analysis software that measure tissue luminance G have been employed for the identification of oral mucosa diseases. Fluorescence visualization is presumably based on the decrease in epithelial flavin adenine dinucleotide content and luminance G values due to the destruction of collagen cross-links [fluorescence visualization loss (FVL)]. However, cases with differences between luminance values and histopathological presentation exist. Therefore, additional factors may affect fluorescence visualization. The present study used a portable, non-contact oral mucosa fluorescence visualization device for luminance measurements in seven patients with oral squamous cell carcinoma. Furthermore, Picro-Sirius Red and immunohistochemical staining were performed for CK13, CK17, Ki67, p53 and E-cadherin in the FVL(+) (lesion) and FVL(−) (resection stump) areas to elucidate the principle of fluorescence visualization. Fluorescence was significantly lower in the FVL(+) than in the FVL(−) areas, and the mean luminance G value was 56. The Picro-Sirius Red stain revealed collagen destruction in the FVL(+) areas but no collagen disruption in the FVL(−) areas. CK13 was negative in the FVL(+) and positive in the FVL(−) areas, whereas the opposite pattern was observed for CK17. In the FVL(+) area, p53 staining was positive. E-cadherin expression was enhanced in the FVL(−) areas and reduced in the FVL(+) areas. Furthermore, the luminance G value tended to be lower in cases with weaker E-cadherin staining. The aforementioned results suggest that decreased E-cadherin expression may be a factor that regulates fluorescence visualization.

The Role of HSF1 and the Chaperone Network in the Tumor Microenvironment

Tumors are stressful environments. As tumors evolve from single mutated cancer cells into invasive malignancies they must overcome various constraints and barriers imposed by a hostile microenvironment. To achieve this, cancer cells recruit and rewire cells in their microenvironment to become pro-tumorigenic. We propose that chaperones are vital players in this process, and that activation of stress responses helps tumors adapt and evolve into aggressive malignancies, by enabling phenotypic plasticity in the tumor microenvironment (TME). In this chapter we will review evidence supporting non-cancer-cell-autonomous activity of chaperones in human patients and mouse models of cancer, discuss the mechanisms by which this non-cell-autonomous activity is mediated and provide an evolutionary perspective on the basis of this phenomenon.

Clinical significances of p27 in digestive tract cancers: a comprehensive analysis on immunohistochemistry staining, published literatures, microarray and RNA-seq data

In the present study, we conducted a comprehensive analysis on the clinical roles of p27 protein and p27 gene in digestive tract cancers (DTCs). First, we performed immunohistochemistry staining and found that p27 protein was down-regulated in DTCs. Then we collected 62 publications and calculated the combined hazard ratios (HRs), odds ratios (ORs) and 95% confidence intervals (95% CIs) to clarify the relationships of p27 protein expression with prognoses and clinicopathological parameters. The overall HRs indicated that the down-regulated p27 protein was an independent prognostic biomarker for overall survival (HR: 1.58, 95% CI: 1.38-1.81, P < 0.0001) but not for disease-free survival and cancer-specific survival. The combined ORs indicated that a low expression of p27 protein was positively related to lymph node metastasis (OR: 2.15, 95% CI: 1.57-2.96, P < 0.0001), distant metastasis (OR: 2.02, 95% CI: 1.12-3.63, P = 0.019) and pathology grading (OR: 2.14, 95% CI: 1.75-2.62, P < 0.0001). Additionally, 60 DTCs-related microarray and RNA-seq datasets were obtained to investigate the expression level and clinical value of p27 gene in DTCs patients. We found that the expression level of p27 gene in DTCs was similar to that in normal controls. And no significant associations of p27 gene expression with prognoses and clinicopathological factors were observed. In conclusion, according to our results, it was p27 protein, but not p27 gene, that can function as an effective biomarker to predict the clinical outcome in patients with DTCs. The down-regulation of p27 protein in DTCs may not result from the altered expression of p27 gene.

Prognostic role of HSPs in human gastrointestinal cancer: a systematic review and meta-analysis

Background

Heat shock proteins (HSPs) have been reported to be overexpressed in a wide range of human tumors. It has been shown that HSPs act as an oncogenic regulator and are involved in tumorigenesis. The clinical and prognostic significance of HSPs in gastrointestinal cancers (GICs) remains controversial. The aim of this study was to conduct a meta-analysis to assess the prognostic value of HSPs in GICs.

Materials and methods

A literature search was performed in PubMed, Cochrane Library, Web of Science, and Embase databases. Data on the relationship between expression of HSPs and survival outcomes were extracted. Pooled hazard ratios (HRs) with 95% CI were calculated.

Results

The expression of HSPs was not associated with the overall survival (OS) of GIC patients; however, it was significantly associated with worse OS for gastric cancer (GC) and colorectal cancer (CRC) patients.

Conclusion

Current evidence suggests that a high level of HSPs may not be a potential marker to predict the survival rate for every type of GICs. However, the expression of HSPs may predict a poor prognosis for GC and CRC patients.

Prognostic significance of beta-catenin expression in patients with esophageal carcinoma: a meta-analysis

Many studies have reported β-catenin involvement in the development of esophageal carcinoma (EC), but its prognostic significance for EC patients remains controversial. Therefore, we conducted this meta-analysis to explore the issue in detail. After searching PubMed, EMBASE, Web of Science, and Chinese Biomedical Literature Database, we included a total of ten relevant studies. We pooled the overall survival (OS) data using RevMan 5.2 software. The results showed that aberrant expression of β-catenin was associated with a significant increase of mortality risk (hazard ratio 1.71, 95%CI 1.46-2.01; p<0.00001). Subgroup analyses further suggested that aberrant expression of β-catenin resulted in poor OS of EC patients regardless of histological type of EC, study location or criteria for aberrant expression of β-catenin, and the sensitivity analyses revealed that the result was robust. The meta-analysis revealed that aberrant expression of β-catenin could be a predicative factor of poor prognosis for EC patients.

The human HSP70 family of chaperones: where do we stand?

The 70-kDa heat shock protein (HSP70) family of molecular chaperones represents one of the most ubiquitous classes of chaperones and is highly conserved in all organisms. Members of the HSP70 family control all aspects of cellular proteostasis such as nascent protein chain folding, protein import into organelles, recovering of proteins from aggregation, and assembly of multi-protein complexes. These chaperones augment organismal survival and longevity in the face of proteotoxic stress by enhancing cell viability and facilitating protein damage repair. Extracellular HSP70s have a number of cytoprotective and immunomodulatory functions, the latter either in the context of facilitating the cross-presentation of immunogenic peptides via major histocompatibility complex (MHC) antigens or in the context of acting as "chaperokines" or stimulators of innate immune responses. Studies have linked the expression of HSP70s to several types of carcinoma, with Hsp70 expression being associated with therapeutic resistance, metastasis, and poor clinical outcome. In malignantly transformed cells, HSP70s protect cells from the proteotoxic stress associated with abnormally rapid proliferation, suppress cellular senescence, and confer resistance to stress-induced apoptosis including protection against cytostatic drugs and radiation therapy. All of the cellular activities of HSP70s depend on their adenosine-5'-triphosphate (ATP)-regulated ability to interact with exposed hydrophobic surfaces of proteins. ATP hydrolysis and adenosine diphosphate (ADP)/ATP exchange are key events for substrate binding and Hsp70 release during folding of nascent polypeptides. Several proteins that bind to distinct subdomains of Hsp70 and consequently modulate the activity of the chaperone have been identified as HSP70 co-chaperones. This review focuses on the regulation, function, and relevance of the molecular Hsp70 chaperone machinery to disease and its potential as a therapeutic target.

The Prognostic Impact of Heat Shock Proteins Expression in Patients with Esophageal Cancer: A Meta-Analysis

PURPOSE

Heat shock proteins (HSPs) are highly conserved molecular chaperones. There are various studies that assess the prognostic value of HSPs in patients with esophageal cancer, but the conclusion remains controversial. This is the first meta-analysis study aiming to summarize the evidence on the suitability of HSPs to predict patients' survival.

MATERIALS AND METHODS

Searching PubMed, Web of science and Medline until May 31, 2014, data were compared for overall survival in patients with down-regulated HSPs level with those with up-regulated level. We conducted a meta-analysis of 9 studies (801 patients) that correlated HSPs levels with overall survival. Data were synthesized with hazard ratios (HRs).

RESULTS

The estimated risk of death was 2.93-fold greater in HSP27 negative patients than HSP27 positive patients [95% confidence interval (CI), 1.12-7.62]. When limited to esophageal squamous cell carcinoma (ESCC), the risk of death in HSP27 negative patients seemed more significant (HR, 3.90; 95% CI, 2.35-6.49). Decreased expression of HSP70 was also associated with worse survival in esophageal cancer (HR, 2.83; 95% CI, 1.90-4.23) and, when limited to ESCC, HR was 3.21 (95% CI, 1.94-5.30). Data collected, however, were not sufficient to determine the prognostic value of HSP90 in patients with ESCC nor esophageal adenocarcinomas (EADC).

CONCLUSION

In this meta-analysis, reduced HSP27 and HSP70 expressions were associated with poor survival in patients with esophageal cancer, especially esophageal squamous cell carcinoma.

The complex function of hsp70 in metastatic cancer

Elevated expression of the inducible heat shock protein 70 (Hsp70) is known to correlate with poor prognosis in many cancers. Hsp70 confers survival advantage as well as resistance to chemotherapeutic agents, and promotes tumor cell invasion. At the same time, tumor-derived extracellular Hsp70 has been recognized as a "chaperokine", activating antitumor immunity. In this review we discuss localization dependent functions of Hsp70 in the context of invasive cancer. Understanding the molecular principles of metastasis formation steps, as well as interactions of the tumor cells with the microenvironment and the immune system is essential for fighting metastatic cancer. Although Hsp70 has been implicated in different steps of the metastatic process, the exact mechanisms of its action remain to be explored. Known and potential functions of Hsp70 in controlling or modulating of invasion and metastasis are discussed.

Systematic review and meta-analysis of tumor biomarkers in predicting prognosis in esophageal cancer

BACKGROUND

Esophageal cancer (EC) is a frequently occurring cancer with poor prognosis despite combined therapeutic strategies. Many biomarkers have been proposed as predictors of adverse events. We sought to assess the prognostic value of biomarkers in predicting the overall survival of esophageal cancer and to help guide personalized cancer treatment to give patients the best chance at remission.

METHODS

We conducted a systematic review and meta-analysis of the published literature to summarize evidence for the discriminatory ability of prognostic biomarkers for esophageal cancer. Relevant literature was identified using the PubMed database on April 11, 2012, and conformed to the REMARK criteria. The primary endpoint was overall survival and data were synthesized with hazard ratios (HRs).

RESULTS

We included 109 studies, exploring 13 different biomarkers, which were subjected to quantitative meta-analysis. Promising markers that emerged for the prediction of overall survival in esophageal squamous cell cancer included VEGF (18 eligible studies, n=1476, HR=1.85, 95% CI, 1.55-2.21), cyclin D1 (12 eligible studies, n=1476, HR=1.82, 95% CI, 1.50-2.20), Ki-67 (3 eligible studies, n=308, HR=1.11, 95% CI, 0.70-1.78) and squamous cell carcinoma antigen (5 eligible studies, n=700, HR=1.28, 95% CI, 0.97-1.69); prognostic markers for esophageal adenocarcinoma included COX-2 (2 eligible studies, n=235, HR=3.06, 95% CI, 2.01-4.65) and HER-2 (3 eligible studies, n=291, HR=2.15, 95% CI, 1.39-3.33); prognostic markers for uncategorized ECs included p21 (9 eligible studies, n=858, HR=1.27, 95% CI, 0.75-2.16), p53 (31 eligible studies, n=2851, HR=1.34, 95% CI, 1.21-1.48), CRP (8 eligible studies, n=1382, HR=2.65, 95% CI, 1.64-4.27) and hemoglobin (5 eligible studies, n=544, HR=0.91, 95% CI, 0.83-1.00).

CONCLUSIONS

Although some modest bias cannot be excluded, this review supports the involvement of biomarkers to be associated with EC overall survival.

Significance of CD133 expression in esophageal squamous cell carcinoma

Background

CD133 was recently reported to be a cancer stem cell marker and a prognostic marker for several tumors. However, few studies have investigated CD133 expression in esophageal squamous cell carcinoma (ESCC). Therefore, we examined whether CD133 could serve as a prognostic marker of ESCC and investigated the correlation between CD133 expression and the clinicopathological findings of ESCC patients and several markers.

Methods

We studied 86 ESCC patients who underwent curative surgery without neoadjuvant treatment at Tohoku University Hospital (Sendai, Japan) between January 2000 and December 2005. We analyzed tissue specimens by immunohistochemical staining for CD133, p53, p16, p27, murine double minute 2 (MDM2), Ki-67, and epidermal growth factor receptor (EGFR).

Results

Pathological tumor depth and tumor stage were significantly more advanced among CD133-negative patients than among CD133-positive patients. A log-rank test showed that CD133 immunoreactivity was significantly correlated with the overall survival of the patients (P = 0.049). However, multivariate analysis showed that it was not significantly correlated (P = 0.078). Moreover, CD133 was significantly positively correlated with p27 immunoreactivity (P = 0.0013) and tended to be positively correlated with p16 immunoreactivity (P = 0.057). In addition, p16 immunoreactivity was correlated with smoking history (P = 0.018), pathological lymph node status (P = 0.033), and lymphatic invasion (P = 0.018).

Conclusions

This study indicated that CD133 immunoreactivity is a good predictor of prognosis in ESCC patients. In addition, CD133 may play a role in the regulation of tumor cell cycle through p27 and p16 in ESCC. At present, it thus remains controversial whether CD133 expression is a valid prognostic marker for ESCC. To elucidate this relationship, further investigations are required.

Prognostic relevance of Bmi-1 expression and autoantibodies in esophageal squamous cell carcinoma

Background

Overexpression of Bmi-1 has been observed in a variety of cancers, and it has been suggested to be an independent prognostic marker for the patients. The objective of this study was to determine the level of Bmi-1 expression or its autoantibodies in human esophageal squamous cell carcinoma (ESCC) and to correlate it with clinicopathologic data.

Methods

We first examined Bmi-1 expression in ESCC cell lines and tumor samples by RT-PCR and Western blot analysis. We then analyzed Bmi-1 protein expression in 171 clinicopathologically characterized ESCC cases by immunohistochemistry. In addition, we detected its autoantibodies in sera of patients with ESCC by ELISA.

Results

We found that Bmi-1 expression was higher in the immortalized cells, cancer cell lines and most cancer tissue than in non-tumorous control tissue at both mRNA and protein level. In addition, Bmi-1 expression was observed in 64.3% (110 of 171) archive ESCC specimen by immunohistochemistry analysis, and the location of Bmi-1 in ESCC was in the nuclei instead of cytoplasm of tumor cells. There was a significant difference of Bmi-1 expression in patients categorized according to stage (P = 0.003) and pN classification (P = 0.047). Multivariate analysis suggested that Bmi-1 expression was an independent prognostic marker for ESCC patients. A prognostic significance of Bmi-1 was also found in the subgroup of T3~T4 and N1 tumor classification. Bmi-1 autoantibodies were detected in sera of 39.0% (62 of 159) ESCC patients. The correlations between anti-Bmi-1 antibodies and tumor stage (P = 0.040), or lymph node status (P < 0.001) were significant.

Conclusions

Our results suggest that Bmi-1 protein is a valuable marker of ESCC progression. The presence of Bmi-1 autoantibodies in sera from patients with ESCC may have clinical utility in esophageal cancer diagnosis.

Reduced axin protein expression is associated with a poor prognosis in patients with squamous cell carcinoma of esophagus

AIMS

Our study investigates the significance of the expression of Wnt pathway proteins including beta-catenin, Axin, beta-transducin-repeat-containing protein (beta-TrCP), and adenomatous polyposis coli (APC) in squamous cell carcinoma of the esophagus (ESCC).

METHODS

Immunohistochemical analysis was performed on paraffin-embedded tissue specimens from 128 resected ESCC tumors to detect the expression of beta-catenin, Axin, beta-TrCP, and APC. Correlation between immunoexpression, clinicopathological parameters, and patient survival was analyzed.

RESULTS

Increased beta-catenin expression was noted in 22 (18.2%) of 121 tumor specimens. Reduced expression of Axin, beta-TrCP, and APC was observed in 57 (46.0%) of 124, 29 (24.4%) of 119, and 54 (48.2%) of 119 specimens, respectively. No correlation was found among these protein expressions. Axin protein expression was inversely correlated with tumor invasion depth (P = 0.033). Reduced Axin protein expression, lymph node involvement, and distant metastasis were significant negative predictors for overall survival and disease-free survival on univariate analysis. In multivariate analysis, reduced Axin expression remained a significant prognostic factor for patients with ESCC (P = 0.005).

CONCLUSIONS

Reduced Axin expression was observed in 46% of ESCC tumor specimens and was associated with poor prognosis in patients with ESCC. Further study is mandatory to elucidate the underlying mechanism responsible for loss of Axin expression and the role of Axin in ESCC tumorigenesis.

Elevation of circulating big endothelin-1: an independent prognostic factor for tumor recurrence and survival in patients with esophageal squamous cell carcinoma

BACKGROUND

Endothelin(ET) axis plays a key role in many tumor progression and metastasis via various mechanisms such as angiogenesis, mediating extracellular matrix degradation and inhibition of apoptosis. However, there is limited information regarding the clinical significance of plasma big ET-1 levels in esophageal cancer patients. Circulating plasma big ET-1 levels were measured in patients with esophageal squamous cell carcinoma(ESCC) to evaluate the value of ET-1 as a biomarker for predicting tumor recurrence and patients survival.

METHODS

Preoperative plasma big ET-1 concentrations were measured by an enzyme linked immunosorbent assay(ELISA) in 108 ESCC patients before surgery, and then again at 1,2,3,10 and 30 days after curative radical resection for ESCC. The association between preoperative plasma big ET-1 levels and clinicopathological features, tumor recurrence and patient survival, and their changes following surgery were evaluated.

RESULTS

The preoperative plasma big ET-1 levels in ESCC patients were significantly higher than those in controls. And there was a significant association between plasma big ET-1 levels and disease stage, as well as invasion depth of the tumor and lymph node status. Furthermore, plasma big ET-1 levels decreased significantly after radical resection of the primary tumor and patients with postoperative recurrence had significantly higher plasma big ET-1 levels than that of patients without recurrence. Finally, the survival rate of patients with higher plasma big ET-1 concentrations (>4.3 pg/ml) was significantly lower than that of patients with lower level (< or = 4.3 pg/ml). Multivariate regression analysis showed that plasma big ET-1 level is an independent prognostic factor for survival in patients with ESCC.

CONCLUSION

Plasma big ET-1 level in ESCC patients may reflect malignancy and predict tumor recurrence and patient survival. Therefore, the preoperative plasma big ET-1 levels may be a clinically useful biomarker for choice of multimodality therapy in ESCC patients.

Reduced membranous beta-catenin protein expression is associated with metastasis and poor prognosis in squamous cell carcinoma of the esophagus

OBJECTIVES

The aim of this study was to evaluate, by immunohistochemical analysis, the protein expression of beta-catenin and p53 in resected esophageal squamous cell carcinoma specimens. The clinical relevance and prognostic significance of the expression of these proteins were also analyzed.

METHODS

Immunohistochemistry was performed on paraffin-embedded tissue specimens from 68 resected esophageal squamous cell carcinoma tumor specimens to detect the expression of beta-catenin and p53. The correlation between the results of immunoexpression and the clinicopathologic parameters and patient survival was processed statistically.

RESULTS

Reduced membranous beta-catenin expression was noted in 43 (63.2%) of 68 tumor specimens. Increased expression of p53 was observed in 43 (63.2%) of 68 specimens. Reduced membranous beta-catenin protein expression was associated with the presence of distant metastasis (P = .006). Patients with reduced membranous beta-catenin expression had a worse prognosis than patients with normal membranous beta-catenin expression (P = .005). Patients with combined increased p53 and reduced membranous beta-catenin protein expression had the worst prognosis (P = .012). In a multivariate survival analysis, reduced membranous beta-catenin expression and nodal involvement were independent prognostic factors (P = .004 and .019, respectively).

CONCLUSIONS

Immunohistochemical analysis revealed that reduced membranous beta-catenin protein expression was associated with the presence of distant metastasis and a poor prognosis in patients with esophageal squamous cell carcinoma. Combined increased p53 and reduced membranous beta-catenin protein expression indicated a very poor prognosis in patients with esophageal squamous cell carcinoma. Further investigation is needed to understand the roles of beta-catenin and p53 in the tumorigenesis and metastasis of esophageal squamous cell carcinoma.

Altered expression of the urokinase receptor homologue, C4.4A, in invasive areas of human esophageal squamous cell carcinoma

C4.4A is a glycolipid-anchored membrane protein with structural homology to the urokinase-type plasminogen activator receptor (uPAR). Although C4.4A was identified as a metastasis-associated protein little is known about its actual expression and possible function in malignant disease. In the present study, we have therefore analyzed the expression of C4.4A in 14 esophageal squamous cell carcinomas (ESCC). Normal squamous esophageal epithelium shows a strong cell surface associated C4.4A expression in the suprabasal layers, whereas basal cells are negative. Upon transition to dysplasia and carcinoma in situ the expression of C4.4A is abruptly and coordinately weakened. Double immunofluorescence staining of normal and dysplastic tissue showed that C4.4A colocalizes with the epithelial cell surface marker E-cadherin in the suprabasal cells and has a complementary expression pattern compared to the proliferation marker Ki-67. A prominent, but frequently intracellular, C4.4A expression reappeared in tumor cells located at the invasive front and local lymph node metastases. Because C4.4A was reported previously to be a putative laminin-5 (LN5) ligand, and both proteins are expressed by invasive tumor cells, we analyzed the possible coexpression of C4.4A and the gamma 2-chain of LN5 (LN5-gamma 2). Although these proteins are indeed expressed by either neighboring cancer cells or in a few cases even coexpressed by the same cells in the tumor front and metastases, we found no evidence for a general colocalization in the extracellular compartment by confocal microscopy. In conclusion, C4.4A is expressed during invasion and metastasis of human ESCC and may thus provide a new histological marker in this disease.

Effect of endothelin-1 in esophageal squamous cell carcinoma invasion and its correlation with cathepsin B

AIM: To investigate the effect of endothelin-1 in the invasion of esophageal cancer and determine whether cathepsin B plays a role in the course.

METHODS: Western blotting was employed to detect the expression of ET-1 protein in 75 samples of esophageal squamous cell cancer and matched normal esophageal mucosa. Bosentan, a dual ET (A/B)-receptor antagonist, was used to inhibit the binding of endothelin-1 and its receptors and cut down its biological role. In vitro matrigel invasion assays were made to show the invasive ability of esophageal cancer cells with and without bosentan. Subsequently, we evaluated cathepsin B activity and expression in EC9706 cell with and without bosentan.

RESULTS: We found 74.7% (56/75) tumors had an overexpression of ET-1 protein by Western blotting. Bosentan significantly inhibited matrigel invasion of cancer cells in vitro. EC9706 cells have a positive expression of cathepsin B protein, and bosentan can down-regulate its expression and activity.

CONCLUSION: Endothelin-1 may enhance the invasive ability of human esophageal cancer cells, and its role is correlated with cathepsin B.

Aberrant nuclear localization of beta-catenin without genetic alterations in beta-catenin or Axin genes in esophageal cancer

Background

β-catenin is a multifunctional protein involved in two apparently independent processes: cell-cell adhesion and signal transduction. β-catenin is involved in Wnt signaling pathway that regulates cellular differentiation and proliferation. In this study, we investigated the expression pattern of β-catenin and cyclin D1 using immunohistochemistry and searched for mutations in exon 3 of the β-catenin gene and Axin gene in esophageal squamous cell carcinoma.

Materials and methods

Samples were obtained from 50 esophageal cancer patients. Immunohistochemical staining for β-catenin and cyclin D1 was done. Mutational analyses of the exon3 of the β-catenin gene and Axin gene were performed on tumors with nuclear β-catenin expression.

Results

Four (8%) esophageal cancer tissues showed high nuclear β-catenin staining. Overexpression of cyclin D1 was observed in 27 out of 50 (54%) patients. All four cases that showed nuclear β-catenin staining overexpressed cyclin D1. No relationship was observed between the expression pattern of β-catenin and cyclin D1 and age, sex, tumor size, stage, differentiation grade, lymph node metastasis, response to chemotherapy, or survival. No mutational change was found in β-catenin exon 3 in the four cases with nuclear β-catenin staining. Sequencing analysis of the Axin cDNA revealed only a splicing variant (108 bp deletion, position 2302–2409) which was present in the paired normal mucosa.

Conclusion

A fraction of esophageal squamous cell carcinomas have abnormal nuclear accumulation of β-catenin accompanied with increased cyclin D1 expression. Mutations in β-catenin or axin genes are not responsible for this abnormal localization of β-catenin.

Assessment of Clinical Outcome in Patients With Esophageal Squamous Cell Carcinoma Using TNM Classification Score and Molecular Biological Classification

BACKGROUND

The aim of this study was to assess the clinical outcome in patients with esophageal squamous cell carcinoma (ESCC) by using molecular biological classification based on immunohistochemical analysis in addition to tumor, node, metastasis system (TNM) classification.

METHODS

Samples from 71 patients with ESCC who underwent surgery were analyzed immunohistochemically. Cyclin B1, E-cadherin, Bag-1, and heat-shock protein 70 were selected as the molecular biological parameters. The utility of molecular biological classification on clinical impact was examined and compared with TNM classification.

RESULTS

Three patients were diagnosed as stage 0, 14 as stage I, 20 as stage II, 19 as stage III, and 15 as stage IV by TNM classification. Thirteen patients were classified as stage 0, 17 as stage I, 21 as stage II, 18 as stage III, and 2 as stage IV by molecular biological classification. Molecular biological stage (P < .0001) and TNM stage (P < .0001) were statistically significant prognostic parameters in univariate analysis. Twenty (28.2%) of 71 patients were assigned to the same stage by both classifications, and a significant correlation was identified between the two classifications (P = .0002). Molecular biological classification (P < .01) and TNM classification (P < .0001) were independent prognostic parameters in multivariate analysis. Combined TNM and molecular biological classification accurately reflected clinical outcome (P < .0001).

CONCLUSIONS

Molecular biological classification combined with TNM classification is useful for assessing the prognosis of patients with ESCC.

Differential protein expression between esophageal squamous cell carcinoma and dysplasia, and prognostic significance of protein markers

The aim of the current study was to evaluate the protein expression involved in the progression from dysplasia to invasive esophageal squamous cell carcinomas and to analyze the prognostic value of markers. Immunohistochemistry was performed for cell cycle regulators [p53, p21, p27, p16, cyclin D1, Rb], apoptosis-related proteins [Fas, Fas-L, FADD, TRAIL, DR4, DR5, caspase-8, caspase-3, bcl-2, Bax], tumor suppressor proteins [beta-catenin, E-cadherin, FHIT, Smad 4, VHL, PTEN, KAI-1], and oncoproteins [c-myc, COX-2, EGFR]. Caspase-3, TRAIL, Fas-L, Fas, Smad 4, VHL, E-cadherin, and EGFR revealed significant differences between dysplasia and their corresponding invasive cancer portion in 25 cases. In a total of 118 cases of invasive cancer, proteins with frequent (> or = 60% of the cases) alterations were p53 (overexpression in 64% of SCCs), p27 (loss in 91%), p16 (loss in 81%), and FHIT (loss in 75%). Early clinical stage and bcl-2 immunopositivity were related to the survival rate of patients. In conclusion, caspase-3, TRAIL, Fas-L, Fas, Smad 4, VHL, E-cadherin, and EGFR may be involved in the progression from dysplasia to invasive esophageal SCCs. Clinical stage and bcl-2 are independent prognostic factors throughout the multivariate analysis.

Impact of simultaneous assay, the PCNA, cyclinD1, and DNA content with specimens before and after preoperative radiotherapy on prognosis of esophageal cancer-possible incorporation into clinical TNM staging system

AIM: The aim of the present study is to use immunohisto-chemical methods to investigate the clinical implications of tumor markers in esophageal squamous cell carcinoma and evaluate their impact on prognosis.

METHODS: From November 1990 to December 1996, 47 patients were treated with preoperative radiation followed by radical esophagectomy. All patients were confirmed pathologically as suffering from squamous cell carcinoma. Immunohistochemical stain was done for PCNA, cyclinD1 protein expression and DNA content analyzed by image cytometry. Kaplan-Meier method for single prognostic factor and log-rank test was used to test the significant difference. Cox stepwise regression model and prognosis index model were used for survival analysis with multiple prognostic factors.

RESULTS: Radio-pathological change, T stage and N stage, as the traditional prognostic factors had statistical difference in 3-, 5- and 10-year survival rates. While, tumor cell proliferating marked PCNA, cyclinD1 and DNA content served as independent prognostic factors of esophageal carcinoma. There was definitely an identity between the single and multiple factor analyses. PI was more accurate to evaluate the prognosis of esophageal carcinoma.

CONCLUSION: It is possible that tumor cell proliferating marked PCNA, cyclinD1 and DNA content would become the endpoints for evaluating the prognosis of esophageal carcinoma.

Expression level of valosin-containing protein (p97) is associated with prognosis of esophageal carcinoma

PURPOSE

Esophageal squamous cell carcinoma (ESCC) frequently shows a poor prognosis because of the occurrence of systemic metastasis, mainly via lymphatic vessels. Valosin-containing protein (VCP) has been shown to be associated with antiapoptotic function and metastasis via activation of the nuclear factor-kappaB signaling pathway. In the present study, we examined the association of VCP with the recurrence and prognosis of ESCC.

EXPERIMENTAL DESIGN

VCP expression in 156 ESCC patients [139 males and 17 females; age range, 38-82 (median, 60) years] was analyzed by immunohistochemistry. Staining intensity in tumor cells was categorized as weaker (level 1) or equal to or stronger (level 2) than that in endothelial cells. The correlation of VCP expression between the mRNA and protein levels was examined in 12 patients.

RESULTS

Fifty-seven (37.3%) cases showed level 1 and 96 (62.7%) level 2 VCP expression. Quantitative reverse transcription-PCR analysis revealed greater VCP mRNA expression in level 2 (n = 6) than level 1 cases (n = 6; P < 0.05). ESCC with level 2 expression showed higher rates of lymph node metastasis (P < 0.01) and deep tumor invasion (P < 0.01), and poorer disease-free and overall survival rates (P < 0.001 for both analyses) than ESCC with level 1 expression. Multivariate analysis revealed that VCP expression level is an independent prognosticator for disease-free and overall survival. Furthermore, VCP level was an indicator for disease-free survival in the early (pT1) and the advanced (pT2-pT4) stage groups.

CONCLUSION

This study demonstrated the prognostic significance of VCP expression in ESCC.

Prognostic and clinicopathological features of E-cadherin, α-catenin, β-catenin, γ-catenin and cyclin D1 expression in human esophageal squamous cell carcinoma

AIM: To investigate the expression of E-cadherin, α-catenin, β-catenin, γ-catenin and cyclin D₁ in patients with esophageal squamous cell carcinoma (ESCC), and analyze their interrelationship with clinicopathological variables and their effects on prognosis.

METHODS: Expression of E-cadherin, α-catenin, β-catenin, γ-catenin and cyclin D₁ was determined by EnVision or SABC immunohistochemical technique in patients with ESCC consecutively, their correlation with clinical characteristics was evaluated and analyzed by univariate analysis.

RESULTS: The reduced expression rate of E-cadherin, α-catenin, β-catenin and γ-catenin was 88.7%, 69.4%, 35.5% and 53.2%, respectively. Cyclin D1 positive expression rate was 56.5%. Expression of γ-catenin was inversely correlated with the degree of tumor differentiation and lymph node metastasis (χ² = 4.183 and χ² = 5.035, respectively, P < 0.05), whereas the expression of E-cadherin was correlated only with the degree of differentiation (χ² = 5.769, P < 0.05). Reduced expression of E-cadherin and γ-catenin was associated with poor differentiation of tumor, reduced expression of γ-catenin was also associated with lymph node metastasis. There obviously existed an inverse correlation between level of E-cadherin and γ-catenin protein and survival. The 3-year survival rates were 100% and 56% in E-cadherin preserved expression group and in reduced expression one and were 78% and 48% in γ-catenin preserved expression group and in reduced expression one, respectively. The differences were both statistically significant. Correlation analysis showed the expression level of α-catenin correlated with that of E-cadherin and β-catenin (P < 0.05).

CONCLUSION: The reduced expression of E-cadherin and α-catenin, but not β-catenin, γ-catenin and cyclin D1, implies more aggressive malignant behaviors of esophageal carcinoma cells and predicts the poor prognosis of patients.

Expression of Egr-1, c-fos and cyclin D1 in esophageal cancer and its precursors: An immunohistochemical and in situ hybridization study

AIM: To examine the expression of Egr-1, c-fos and cyclin D1 at both transcript and protein levels in esophageal carcinoma and to correlate the level of their expressions with precancerous and paracancerous esophageal lesions and esophageal carcinoma.

METHODS: In situ hybridization and immunohistochemistry were used respectively to detect the expression of mRNA and proteins of Egr-1, c-fos and cyclin D1 in 70 cases of esophageal squamous cell carcinoma and their corresponding para-cancerous mucosa and upper cut edge mucosa.

RESULTS: In situ hybridization and immunohistochemistry showed positive staining of all three mRNAs in the cytoplasm and those of the proteins in nuclei. Overexpression of Egr-1, c-fos and cyclin D1 mRNAs and their proteins was found in dysplasia and squamous carcinomas. The expression level of Egr-1 and c-fos was high, and cyclin D1 was low in dysplasia mucosa, whereas the expression of Egr-1 was decreased, c-fos was maintained and cyclin D1 was increased in the cancers. The expression of both c-fos and cyclinD1 was consistent between the mRNA and protein in their corresponding high expression lesions.

CONCLUSION: The expression of Egr-1, c-fos and cyclin D1 varies in esophageal precancerous lesions and cancer tissues, suggesting an involvement of these genes in the development of esophageal carcinoma.

Nuclear BAG-1 expression is a biomarker of poor prognosis in esophageal squamous cell carcinoma

Apoptosis is one of the critical biological factors that correlate with the biological behavior of malignant tumors including cancer progression and clinical outcome. The present study was performed to clarify the clinical implications of BAG-1, a bcl-2 binding protein in esophageal squamous cell carcinoma (ESCC). Seventy-one cases with ESCC were investigated. Immunohistochemical study of BAG-1 was performed on resected specimens. The expression pattern of BAG-1 in nuclei and/or cytoplasm was analyzed and correlated with TNM classification, vessel invasion, survival period after surgery. BAG-1 expression in the nuclei was related to the depth of tumor invasion (P = 0.0381) but not to any other clinicopathologic parameters. The cytoplasmic staining pattern of BAG-1 exhibited no correlation with clinicopathologic parameters. Univariate analysis (P < 0.05), but not multivariate analysis, revealed significantly poor prognosis for ESCC cases exhibiting positive nucleic staining for BAG-1. Our data suggests that BAG-1 expression in the nuclei of ESCC plays an important role in tumor development and may be useful for predicting the prognosis after surgery.

Heat shock protein 70 (Hsp70) membrane expression on head-and-neck cancer biopsy-a target for natural killer (NK) cells

PURPOSE

Heat shock protein 70 (Hsp70) was detected on the cell membrane of human tumor cell lines, but not on normal cells. Here we studied Hsp70 membrane expression as a target for natural killer (NK) cells on tumor material and control tissues of head-and-neck cancer patients.

METHODS AND MATERIALS

Membrane-bound Hsp70 was determined by flow cytometry on single-cell suspensions of tumors and the corresponding normal tissues of head-and-neck cancer patients. The cytolytic activity of NK cells against Hsp70-positive tumor cells was measured in a standard cytotoxicity assay.

RESULTS

In total, 54 of 74 primary tumors were found to be Hsp70 membrane-positive (73%); tongue/mouth, 21 of 24 (88%); oropharynx, 13 of 20 (65%); hypopharynx, 3 of 6 (50%); larynx, 8 of 11 (73%); trachea 1 of 2 (50%); esophagus, 4 of 5 (80%); lymph node metastases, 4 of 6 (67%). The corresponding control tissue was negative for membrane-bound Hsp70. Biopsies (6 of 6) of patients after in vivo gamma-irradiation (fractionated 5 x 2 Gy) were strongly Hsp70 membrane-positive. Irradiated, Hsp70-positive tumor cells are targets for Hsp70-peptide stimulated NK cells.

CONCLUSION

An irradiation-inducible, tumor-selective Hsp70 membrane localization provides a target structure for Hsp70-peptide stimulated human NK cells.

Synergistic decline in expressions of p73 and p21 with invasion in esophageal cancers

The significance of the p73 gene, a homologue of the p53 gene, in esophageal cancers is not fully understood. In order to clarify the role of p73 expression in esophageal cancers, p73 expression was immunohistochemically investigated in 106 surgically resected esophageal cancers and the results were compared with various clinicopathological factors. In normal esophageal epithelium, the expression of p73 was observed only in the nuclei of basal cells. In esophageal cancers, p73 immunoreactivity was observed in all intraepithelial lesions except one cancer, and was reduced with cancer invasion, to 78% and 64% at superficial invasion and deep invasion sites, respectively. However, p73 expression was not correlated with any other clinicopathological factor. The expressions of p53 and p21 were also investigated in esophageal cancer. To evaluate the status of the p53 gene mutation immunohistochemically, two monoclonal antibodies (DO7 and PAb240) were used. There seemed to be an inverse correlation between p73 expression and p53 mutation. Moreover, the expression of p21 was highly correlated with p73 expression irrespective of the p53 mutation status. In human esophageal cancers, p73 expression decreased with increasing degree of tumor invasion, and its decreased expression in local advanced tumor caused down-regulation of p21 expression, which might reflect tumor progression.

Expression of e-cadherin and β-catenin in human esophageal squamous cell carcinoma: relationships with prognosis

AIM: To elucidate the expression of E-cadherin and β-catenin correlating with its clinical outcome in patients with esophageal squamous cell carcinoma (ESCC), by analyzing their interrelationship with clinicopathological variables and their effects on progress and prognosis.

METHODS: Expression of E-cadherin and β-catenin was determined by SP immunohistochemical technique in patients with ESCC consecutively, their correlation with clinical characteristics was evaluated and analyzed by multivariate analysis.

RESULTS: The rate of expression of E-cadherin decreased to 66.03% (70/106) in ESCC and the protein level was negative correlated with histologic grade, tumor size, clinical staging, lymph node metastasis and venous invasion. Whereas the expression rate of β-catenin was reduced to 69.8% (74/106) and the level of protein expression correlated only with histologic grade. There obviously existed inverse correlation between level of E-cadherin protein and survival, especially in stage I, IIa, IIb (P = 0.0033), Patients with low-expressing tumors for β-catenin and non-expressing tumors for E-cadherin/β-catenin had lower survival period than those with normal-expressing ones (P = 0.0501 and P = 0.0080, respectively). Patients with diminished expression of E-cadherin as grade II or III had shorter survival period than those with normally expressing and grade I, no significance existed between grade I and grade II or III with respect to different status of E-cadherin expression. Furthermore, Correlation analysis showed level of E-cadherin correlated with that of β-catenin (P = 0.005). Cox proportional hazards model analysis suggested downregulation of E-cadherin was an important factor indicating poor prognosis.

CONCLUSION: As a probable independent prognostic factor, it correlates with overall and disease free survival period, expression of E-cadherin but not β-catenin may predict prognosis in patients with ESCC.

The prognostic significance of lymph node size in patients with squamous esophageal cancer

BACKGROUND

The prognosis of patients with esophageal cancer remains dismal, and their care poses a great challenge of customizing therapeutic strategies for individual patients. Lymph node staging is still less than ideal in esophageal cancer patients. Therefore, we investigated a new approach to lymph node analysis.

METHODS

One hundred eighty-seven patients curatively resected for squamous cell cancer of the esophagus were studied. The long diameter of the largest metastatic lymph node (MLN) was measured on a histopathologic slide and was considered as the MLN size.

RESULTS

Patient survival decreased with each millimeter increment in MLN size. By using MLN size as the lymph node classification criterion, patients with MLN <10 mm had both a significantly better overall and cancer-specific survival than those with MLN >or=10 mm. Patients with fewer than four MLNs were separated into prognostic groups according to the MLN size. Among the several prognostic factors, MLN size remained the strongest independent predictor of survival by multivariate analysis. This nodal analysis allowed stratification of patients into four stages with distinctly different survivals.

CONCLUSIONS

This approach supplements traditional nodal staging strategies and therefore has potential for guiding the development of treatment strategies in this carcinoma.

Expression of heat shock protein 70 in grossly resected esophageal squamous cell carcinoma

BACKGROUND

The aim of the present study was to use immunohistochemical methods to clarify the clinical implication of heat shock protein (HSP) 70 expression in esophageal squamous cell carcinoma and to investigate the function of HSP70 as a chaperone for p53.

METHODS

Seventy-one patients with esophageal squamous cell carcinoma were admitted in the present study. Expression of HSP70 was analyzed by immunohistochemistry and correlated with TNM classification, vessel invasion, p53 expression, and clinical outcome after operation.

RESULTS

Overexpression of HSP70 was related to sex (p < 0.05), tumor configuration (p < 0.05), lymph node metastasis (p < 0.01), and lymphatic vessel invasion (p < 0.05). Expression of p53 and HSP70 were not correlated with each other (p = 0.824). Esophageal squamous cell carcinoma with HSP70 expression exhibited a significantly better prognosis compared with HSP70-negative esophageal squamous cell carcinoma in univariate analysis (p < 0.05), but no significance was found in multivariate analysis.

CONCLUSIONS

We suggest that HSP70 expression might be of use to assess the progression, lymph node metastasis, and lymphatic vessel invasion of esophageal squamous cell carcinoma. Inasmuch as both lymph node metastasis and HSP70 expression are prognostic variables in esophageal squamous cell carcinoma, examination of HSP70 expression may be of use to assess clinical outcome after operation.

Expression, deletion [was deleton] and mutation of p16 gene in human gastric cancer

AIM

To investigate the relationship between the expression of p16 gene and the gastric carcinogenesis, depth of invasion and lymph node metastases, and to evaluate the deletion and mutation of exon 2 in p16 gene in gastric carcinoma.

METHODS

The expression of p16 protein was examined by streptavidin-peroxidase conjugated method (S-P);the deletion and mutation of p16 gene were respectively examined by polymerase chain reaction (PCR) and polymerase chain reaction single-strand conformation polymorphism analysis (PCR-SSCP) in gastric carcinoma.

RESULTS

Expression of p16 protein was detected in 96.25% (77/80) of the normal gastric mucosa, in 92.00% (45/50) of the dysplastic gastric mucosa and in 47.54% (58/122) of the gastric carcinoma. The positive rate of p16 protein expression in gastric carcinoma was significantly lower than that in normal gastric mucosa and dysplastic gastric mucosa (P < 0.05). The positive rate of p16 protein expression in mucoid carcinoma 10.00% (1/10) was significantly lower than that in poorly differentiated carcinoma 51.22% (21/41), undifferentiated carcinoma 57.69% (15/26) and signet ring cell carcinoma 62.50% (10/16) (P < 0.05). The positive rate of p16 protein in 30 cases paired primary and lymph node metastatic gastric carcinoma: There was 46.67% (14/30) in primary gastric carcinoma, 16.67% (5/30) in lymph node metastatic gastric carcinoma. The positive rate of lymph node metastatic carcinoma was significantly lower than that of primary carcinoma (P < 0.05). There was of p16 gene mutation in exon 2, but 5 cases displayed deletion of p16 gene in exon 2 in the 25 primary gastric carcinomas.

CONCLUSIONS

The expression loss of p16 protein related to the gastric carcinogenesis, gastric carcinoma histopathological subtypes and lymph metastasis. The mutation of p16 gene in exon 2 may not be involved in gastric carcinogenesis. But the deletion of p16 gene in exon 2 may be involved in gastric carcinogenesis.