Prognostic role of cyclooxygenase-2 in neoadjuvant-treated patients with squamous cell carcinoma of the esophagus

The prognostic value of cyclooxygenase-2 expression in patients with esophageal cancer: evidence from a meta-analysis

Published studies have investigated the prognostic role of cyclooxygenase-2 (COX-2) expression in patients with esophageal cancer (EC), but the result remains controversial. Thus, this meta-analysis was conducted to comprehensively evaluate the impact of COX-2 expression on the prognostic value in patients with EC. Relevant studies were identified from PubMed, EMBASE, and Web of Science databases. Studies that detected the COX-2 expression by immunohistochemistry and evaluated the relationship between COX-2 expression and overall survival (OS) or clinicopathological parameters were used in our analysis. The summary hazard ratios (HRs) or odds ratios were calculated to assess the risk or hazard association. A total of 25 studies, which included 2,465 patients, were included in our meta-analysis. Our analysis suggested that overexpression of COX-2 was associated with poor OS (HR =1.60, 95% CI =1.32–1.94, P<0.001). Subgroup analyses by race, percentage of high/positive COX-2 expression, histology type, treatment, and sample size all suggested significant association. Moreover, overexpression of COX-2 was significantly associated with depth of invasion, lymph node metastasis, distant metastasis, and TNM stage. This meta-analysis suggested that overexpression of COX-2 might serve as a prognostic biomarker for EC. Large well-designed prospective studies are needed to confirm our conclusion.

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.

Cyclooxygenase isoenzyme-2 and vascular endothelial growth factor are associated with poor prognosis in esophageal adenocarcinoma

BACKGROUND

Cyclooxygenase isoenzyme-2 (COX-2) and vascular endothelial growth factor (VEGF) contribute to angiogenesis and are overexpressed in various malignancies. The aim of the study was to evaluate expression, prognostic value and correlation between COX-2 and VEGF expression in esophageal adenocarcinoma (EAC).

METHODS

Surgical specimens of 154 patients with EAC were used to construct a tissue micro array (TMA). TMA sections were immunohistochemically stained for COX-2 and VEGF and scored on intensity of staining.

RESULTS

Estimated 5-year cancer specific survival was 37%. High COX-2 and VEGF expression was observed in 39 (26.5%) and in 77 (53.8%) tumors, respectively. Both markers were associated with poor cancer specific survival (p = .022 and p = .004, respectively, log rank). No significant correlation was found between VEGF and COX-2 expression (r = 063; p = .455). In multivariate analysis, high COX-2 expression (HR 1.65; 95% CI 1.04-2.61; p = .034) was associated with overall survival. In patients with T3 tumors, COX-2 expression was an independent prognostic factor for cancer specific survival (HR 1.81 95% CI 1.10-2.95; p = .019).

CONCLUSIONS

This is the first study that evaluated the prognostic value and correlation of COX-2 and VEGF expression in a large and homogenous population of patients with EAC. No correlation between COX-2 and VEGF expression was found. Both markers were expressed in EAC and were associated with poor prognosis. The findings support the use of COX-2 and VEGF inhibitors in future clinical studies.

Cyclooxygenase-2 polymorphisms and susceptibility to esophageal cancer: a meta-analysis

Esophageal cancer (EC) is one of the most common cancers worldwide with 5-year survival rate less than 10%. However, there is a lack of specific genetic markers that could help better understanding the mechanisms of esophageal carcinogenesis, improving the detection rate of EC, and distinguishing histological types. Cyclooxygenase-2 (COX-2) as an inducible enzyme in cancer development and progression is involved in esophageal carcinogenesis. A large number of studies have demonstrated a strong association between COX-2 polymorphisms and EC risk. However, the overall results are still controversial. This controversy may be partly due to the mix-up of esophageal squamous cell carcinoma (ESCC) and adenocarcinoma (EAC). The aim of this study was to investigate the association between COX-2 polymorphisms and susceptibility to ESCC or EAC by conducting a meta-analysis. Seven studies were retrieved reporting a total of 1450 ESCC patients, 523 EAC patients, and 2663 cancer-free control subjects. Five COX-2 polymorphisms were addressed, including -765G>C (rs20417), -1195G>A (rs689465), -1290A>G (rs689466), -8473T>C (rs5275) and -1759G>A (rs3218625). Meta-analysis results showed that the -765C allele is significantly associated with the susceptibility to both ESCC and EAC especially in Asian populations. In addition, there was a significant association between the -8473C allele and the susceptibility to EAC in Caucasian populations. In conclusion, our meta-analysis suggests that the -765C allele of the COX-2 gene might be a potential risk factor for both ESCC and EAC especially in Asian populations, while the -8473C allele might be a risk factor for EAC in Caucasian populations.

Meta-analysis: clinicopathological and prognostic significance of cyclooxygenase-2 expression on oesophageal squamous cell carcinoma

BACKGROUND

Cyclooxygenase-2 (COX-2) is involved in oesophageal carcinogenesis, but the clinical and prognostic significance of COX-2 expression in oesophageal squamous cell carcinoma (ESCC) remains controversial.

AIM

To evaluate the clinicopathological and prognostic role of COX-2 expression in ESCC.

METHODS

Studies assessing clinical or prognostic significance of COX-2 expression in ESCC published until December 2008 were selected. A meta-analysis was performed to clarify the impact of COX-2 expression on clinicopathological parameters or overall survival (OS) in ESCC.

RESULTS

A total of 19 studies met the inclusion criteria, among which 17 studies were about the clinicopathological significance of COX-2 expression in ESCC, 12 studies were dealing with prognostic role of COX-2 expression in ESCC and 10 studies evaluated both of them. Overexpression of COX-2 was significantly correlated with not only the depth of invasion and TNM stage, with a combined odds ratio (OR) of 0.55 (95%CI: 0.34-0.90, Z = 2.41, P = 0.02) and 0.55 (95%CI: 0.32-0.95, Z = 2.13, P = 0.03) respectively but also the reduced OS with relative risk (RR) 1.42, 95% CI: 1.07-1.90, Z = 2.43, P = 0.02).

CONCLUSIONS

COX-2 might play an important role in the progress of ESCC, overexpression of COX-2 correlates with not only the depth of invasion and TNM stage but also the reduced OS. COX-2 might be a potential therapy target for ESCC and work as a prognostic factor for ESCC patients, yet the clinicopathological and prognostic role of COX-2 in ESCC still needs further confirmation by well-designed prospective studies.

Polymorphism in COX-2 modifies the inverse association between Helicobacter pylori seropositivity and esophageal squamous cell carcinoma risk in Taiwan: a case control study

Background

Overexpression of Cyclooxygenase-2 (COX-2) was observed in many types of cancers, including esophageal squamous cell carcinoma (ESCC). One functional SNP, COX-2 -1195G/A, has been reported to mediate susceptibility of ESCC in Chinese populations. In our previous study, the presence of Helicobacter pylori (H. pylori) was found to play a protective role in development of ESCC. The interaction of COX-2 and H. pylori in gastric cancer was well investigated. However, literature on their interaction in ESCC risk is scarce. The purpose of this study was to evaluate the association and interaction between COX-2 single nucleotide polymorphism (SNP), H. pylori infection and the risk of developing ESCC.

Methods

One hundred and eighty patients with ESCC and 194 controls were enrolled in this study. Personal data regarding related risk factors, including alcohol consumption, smoking habits and betel quid chewing, were collected via questionnaire. Genotypes of the COX-2 -1195 polymorphism were determined by PCR-based restriction fragment length polymorphism. H. pylori seropositivity was defined by immunochromatographic screening test. Data was analyzed by chi-squared tests and polytomous logistics regression.

Results

In analysis adjusting for the covariates and confounders, H. pylori seropositivity was found to be inversely association with the ESCC development (adjusted OR: 0.5, 95% CI: 0.3 – 0.9). COX-2 -1195 AA homozygous was associated with an increased risk of contracting ESCC in comparison with the non-AA group, especially among patients with H. pylori seronegative (adjusted OR ratio: 2.9, 95% CI: 1.2 – 7.3). The effect was strengthened among patients with lower third ESCC (adjusted OR ratio: 6.9, 95% CI 2.1 – 22.5). Besides, H. pylori seropositivity conveyed a notably inverse effect among patients with COX-2 AA polymorphism (AOR ratio: 0.3, 95% CI: 0.1 – 0.9), and the effect was observed to be enhanced for the lower third ESCC patients (AOR ratio: 0.09, 95% CI: 0.02 – 0.47, p for multiplicative interaction 0.008)

Conclusion

H. pylori seropositivity is inversely associated with the risk of ESCC in Taiwan, and COX-2 -1195 polymorphism plays a role in modifying the influence between H. pylori and ESCC, especially in lower third esophagus.

Targets for molecular therapy in esophageal squamous cell carcinoma: an immunohistochemical analysis

Neoadjuvant chemotherapy may improve the outcome of esophageal cancer after esophagectomy, but is accompanied by considerable toxicity by collateral destruction of normal cells. Such side effects may be avoided by developing therapies that specifically target molecular characteristics of tumors. The aim of the present study was to determine the proportion of esophageal squamous cell carcinoma (ESCC) patients that could possibly benefit from (a combination of) currently available targeted therapies, by assessing the frequency of immunohistochemical expression of their target molecular markers in ESCC tissues. Sections from a validated tissue microarray comprising 108 ESCCs were immunohistochemically stained for Bcl-2, c-KIT, cyclo-oxygenase-2 (COX-2), cyclin D1, estrogen receptor (ER), epidermal growth factor receptor (EGFR), Her-2/neu, progesterone receptor (PR), and vascular endothelial growth factor (VEGF). VEGF, cyclin D1, EGFR, and COX-2 could be detected in 55, 42, 40, and 40%, respectively. Her-2/neu, Bcl-2, and c-KIT were detected in 12, 11, and 10% of the tumors, respectively. No nuclear expression of ER or PR was noticed. Concurrent expression of two markers was noticed in 28% of ESCCs, whereas 25% of ESCCs showed concurrent expression of three markers. The concurrent expression of two of the most frequently expressed markers (VEGF, cyclin D1, EGFR, and COX-2) ranged from 11 (COX-2 and EGFR) to 26% (cyclin D1 and VEGF). The expression of all of these four markers was seen in 5% of ESCCs. Promising targets for molecular therapy in ESCC appear to be COX-2, VEGF, EGFR, and cyclin D1, as they are frequently overexpressed. Phase II clinical studies on these molecular markers may therefore be warranted. The role for targeted therapy against ER, PR, Her-2/neu, c-KIT, or Bcl-2 in ESCC seems limited.

Prognostic role of PGE2 receptor EP2 in esophageal squamous cell carcinoma

Prostaglandin E2 (PGE2), a major cyclooxygenase-2 (COX-2) product, has been shown to affect numerous tumorigenic processes. PGE2 acts through G-protein-coupled receptors designated as EPs. Recently it has been documented that PGE2 promotes colon cancer cell growth via EP2. However, the expression and the prognostic role of EP2 in esophageal squamous cell carcinoma (ESCC) remained unknown. From January 1995 to January 2001, tissue samples from 226 patients with ESCC who underwent esophagectomies at our institutions were collected and made into tissue core arrays for study. EP2 expression was examined by immunohistochemical staining and confirmed by Western blot. The clinicopathologic data were then analyzed. EP2 overexpression was observed in 43.4% (98/226) of ESCC. Overexpression of EP2 correlated positively with depth of tumor invasion (T status) (P = 0.016) and was associated with worse overall survival (P = 0.047). In patients without regional or distant lymph node metastasis (N0 or M0), EP2 overexpression was associated with worse overall survival (P = 0.033 and P = 0.003, respectively). Using Cox regression analysis, T status, N status, and M status were the independent factors of overall survival, but EP2 expression was not. However, when focusing on patients with T1-3N0M0 status, EP2 expression became an independent factor of overall survival (P = 0.048). Our results show that EP2 overexpression was associated with worse prognosis, and correlated positively with T status in ESCC. Meanwhile, among those patients at earlier stages, EP2 overexpression significantly disclosed patients at high risks for poor prognosis.

Protein alterations in ESCC and clinical implications: a review

Esophageal squamous cell carcinoma (ESCC) is the predominant histological subtype of esophageal cancer in Asia, characterized by high incidence and mortality rate. Although significant progress has been made in surgery and adjuvant chemoradiotherapy, the prognosis of the patients with this cancer still remains poor. Investigation into protein alterations that occurred in tumors can provide clues to discover new biomarkers for improving diagnosis and guiding targeted therapy. Hundreds of papers have appeared over the past several decades concerning protein alterations in ESCC. This review summarizes all the dysregulated proteins investigated in the disease from 187 published papers and analyzes their contributions to tumor development and progression. We document protein alterations associated with tumor metastasis and the transition from normal esophageal epithelia to dysplasia in order to reveal the most useful markers for prediction of clinical outcome, early detection, and identification of high-risk patients for targeted therapies. In particular, we discuss the largest and most rigorous studies on prognostic implications of proteins in ESCC, in which cyclin D1, p53, E-cadherin and VEGF appeared to have the strongest evidence as independent predictors of patient outcome.

Overexpression of cyclooxygenase-2 is associated with chemoradiotherapy resistance and prognosis in esophageal squamous cell carcinoma patients

Our objective was to investigate whether cyclooxygenase-2 (COX-2) expression can predict the patient's response to chemoradiotherapy (CRT) and ensuing prognosis in esophageal squamous cell carcinoma (ESCC). The clinicopathological and follow-up data of 112 patients with ESCC who underwent CRT from January 2001 to June 2006 were analyzed retrospectively. The immunohistochemical expression level of COX-2 was examined for all biopsy specimens of primary tumors, and the correlation of COX-2 expression with the patient's response to CRT and prognosis was examined. COX-2 positive immunostaining was detected in 111 (99.1%) of the patients, including overexpression in 54 (48.2%) patients and low expression in 58 (51.8%) of the patients. The response of tumors with a low level expression of COX-2 (70.7%, 41/58) was significantly higher than that of tumors with COX-2 overexpression (42.6%, 23/54; P = 0.003). Patients with a low level of COX-2 expression had a higher downstaged rate than those with a high level of COX-2 expression (9/13 vs 2/8), but the difference was not statistically significant (P = 0.08). In the definitive CRT group (91 cases), COX-2 overexpression was significantly associated with poor 3-year overall survival (P = 0.028). Multivariate analysis showed that only metastatic stage (nonregional node metastasis) was an independent prognosis factor. The assessment of COX-2 status may provide additional information to identify ESCC patients with poor chances of response to CRT and potential candidates for more individualized treatment.

Cyclooxygenase-2 expression is related to prognosis in patients with esophageal squamous cell carcinoma

AIM

Esophageal carcinoma is one of the most aggressive malignancies. Many studies have examined various biological factors associated with the malignant potential of esophageal carcinoma. Cyclooxygenase (COX)-2 is overexpressed in various types of human malignancies, including esophageal carcinomas. Although some groups have described COX-2 expression in esophageal adenocarcinoma, few studies have reported COX-2 expression in esophageal squamous cell carcinoma (ESCC).

METHODS

We immunohistochemically investigated relationships between COX-2 overexpression in surgical specimens of primary tumors in 228 patients with ESCC. Relationships between COX-2 expression and clinicopathological factors, including prognosis, were analyzed. COX-2 expressions were classified into 4 criteria: Score 0, no staining; Score 1, <10% staining; Score 2, 10-90% staining; and Score 3, >90% staining.

RESULTS

Scores of COX-2 immunoreactivity in 228 patients were as follows: Score 0, 21 of 228; Score 1, 71of 228; Score 2, 117 of 228; and Score 3, 19 of 228, respectively. COX-2 expression was significantly correlated with depth of invasion and tumor stage (p=0.03 and p=0.04, respectively). The 5-year survival rate of patients decreased significantly with increased expression of COX-2 (p=0.005). Multivariate regression analysis indicated COX-2 expression as an independent prognostic factor for ESCC.

CONCLUSIONS

COX-2 overexpression was significantly correlated with depth of invasion, tumor stage and survival in ESCC. Evaluation of COX-2 expression should be useful for determining tumor properties, including prognosis, in patients with ESCC.

Cyclo-oxygenase-2 over-expression is associated with human esophageal squamous cell carcinoma

Cyclo-oxygenase (COX)-2 is not usually detectable in normal tissues but is induced in inflammation and carcinogenesis. The level of COX-2 is elevated in cancer tissues of the colon, bladder, and skin. In the esophagus, squamous cell carcinoma and adenocarcinoma are known to express COX-2. The purpose of this study was to clarify the association of COX-2 expression with clinicopathological factors of squamous cell carcinoma. The immunohistochemical expression of COX-2 was examined in 48 surgical specimens of esophageal squamous cell carcinoma. Although COX-2 over-expression was more frequently observed in tumors invading the submucosa (T1b, 76.4%), muscularis propria (T2, 57.1%), adventitia, or adjacent organs (T3 approximately 4, 83.3%), even 33.3% of mucosal cancers, such as T1a, showed COX-2 over-expression. COX-2 over-expression was present in 82.3% of lymph node-negative patients but in only 54.8% of lymph node positive patients. There was no difference in COX-2 over-expression between the earlier stages (0 and I, 60%) and more advanced stages (II approximately IV, 69.6%). COX-2 over-expression did not correlate with survival during 3 years of follow-up. These findings suggest that COX-2 is associated with the phenotype of the esophageal squamous cell carcinoma cells, including superficial cancer cells, and may be related to tumor growth in esophageal squamous cell carcinoma.

Cyclooxygenase-2 expression in squamous cell carcinoma of the esophagus

Increased cyclooxygenase-2 expression has been reported to be a poor prognostic indicator in a number of cancers. In this study we investigated the relationship between COX-2 expression in squamous cell carcinoma of the esophagus and tumor characteristics and patient survival. The study group consisted of 90 men and 48 women who underwent esophagectomy for squamous cell carcinoma of the esophagus between October 1984 and May 1985. COX-2 expression was measured by immunohistochemistry in 138 primary cancers, 23 metastatic lymph nodes and 21 normal esophageal stumps. The relationship between the extent of staining for COX-2 and clinicopathological features and survival was determined. The extent of staining for COX-2 in both primary and metastatic cancers was higher than in normal squamous epithelia (P = 0.002 and P < 0.0001 respectively), and the grade of staining in the primary tumor correlated positively with the finding of lymph node metastases (P = 0.03). The 5-year survival rate in patients with less than 10% COX-2 positive cells was 47.5% compared to 23.2% in patients with more than 10% COX-2 positive cells (P = 0.0036). The relationship between survival and COX-2 staining was not due to COX-2 being a surrogate marker for TNM stage. Our results show that the expression of COX-2 is elevated in squamous cell carcinoma of the esophagus compared to normal epithelium and correlates with lymph node metastases. Survival was longer in those patients whose tumors expressed lower levels of COX-2.

Expression of cyclooxygenase-2 in esophageal carcinoma and its correlation with angiogenesis

AIM: To investigate the expression of cyclooxygenase-2 (COX-2) and its correlation with the angiogenesis and clinicopathological features in esophageal carcinoma.

METHODS: Ninety tumor specimens resected from patients with squamous cell carcinoma of the esophagus were obtained, and 34 corresponding paracancerous normal tissues were randomly selected as the controls. Immunohistochemical staining was used to detect the expression of COX-2. Monoclonal antiboty against CD34 was used for displaying vascular endothelial cells, and microvascular density (MVD) was determined by counting the CD34-positive cells. The correlations of COX-2 expression with MVD and clinicopathological parameters of the patients were analyzed.

RESULTS: The positive rates of COX-2 and MVD expression in the cancerous tissue were 84.4% and 29.68 ± 3.81, respectively, which were significantly higher than those in the normal esophageal mucosa (20.6%, χ² = 45.47, P = 0.00; 15.12 ± 2.80, t = 20.28, P = 0.00). COX-2 expression was closely correlated with clinical TNM classification (χ² = 7.99, P = 0.005), cellular differentiation (χ² = 7.99, P = 0.005) and lymph node metastasis (χ² = 9.61, P = 0.002) in squamous cell carcinoma of the esophagus. The mean values of MVD were associated with clinical TNM classification (t = -7.09, P = 0.00) and lymph node metastasis (t = -7.90, P = 0.00). The spearman rank correlation test showed that tumor MVD was positively associated with COX-2 expression (r = 0.607, P = 0.00).

CONCLUSION: Over-expression of COX-2 is correlated with tumor invasion and lymph node metastasis in esophageal carcinoma, suggesting that COX-2 contributes to the development of esophageal cancer by promoting angiogenesis.