High cyclooxygenase-2 expression in cervical adenocarcinomas

Functional Gene Clusters in Global Pathogenesis of Clear Cell Carcinoma of the Ovary Discovered by Integrated Analysis of Transcriptomes

Clear cell carcinoma of the ovary (ovarian clear cell carcinoma (OCCC)) is one epithelial ovarian carcinoma that is known to have a poor prognosis and a tendency for being refractory to treatment due to unclear pathogenesis. Published investigations of OCCC have mainly focused only on individual genes and lack of systematic integrated research to analyze the pathogenesis of OCCC in a genome-wide perspective. Thus, we conducted an integrated analysis using transcriptome datasets from a public domain database to determine genes that may be implicated in the pathogenesis involved in OCCC carcinogenesis. We used the data obtained from the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO) DataSets. We found six interactive functional gene clusters in the pathogenesis network of OCCC, including ribosomal protein, eukaryotic translation initiation factors, lactate, prostaglandin, proteasome, and insulin-like growth factor. This finding from our integrated analysis affords us a global understanding of the interactive network of OCCC pathogenesis.

Selected Office Based Anticancer Treatment Strategies

Over the years, the treatment of patients with cancer has varied widely as much because of recent advancements in science and medicine as the philosophies that belie their use. This paper briefly describes many of the prevailing approaches in use today with an attempt to offer some perspective of how to apply these disparate methodologies so that they may be more effectively integrated, resulting in consistently better clinical responses.

Effect of photodynamic therapy combined with Celecoxib on expression of cyclooxygenase-2 protein in HeLa cells

The present study assessed the effect of photodynamic therapy (PDT) combined with Celecoxib (Cel) on cervical cancer HeLa cells. An MTT assay was performed to detect the inhibitory effects of Cel with different concentrations (10, 50, 100, 150, 200, 250 and 300 µg/ml) on the proliferation of HeLa cells. Subsequently, HeLa cells were divided into control group (group H), 50 g/ml Celecoxib group (group C), PDT group (group P), 50 g/ml Cel + PDT group (group P + C) and western blotting and immunohistochemistry were performed to detect the expression of cyclooxygenase-2 (COX-2) protein in the different groups. Cel inhibited HeLa cells proliferation 24 h following administration, among which 200 µg/ml induced a 50% inhibition rate; the relative expression level of COX-2 protein in group P + C was significantly decreased compared with that in either group C or group P (P<0.05). Cel inhibited the proliferation of human cervical cancer cells in a concentration-dependent manner, and combined PDT therapy may improve treatment outcomes.

Cyclooxygenase-2 is associated with malignant phenotypes in human lung cancer

The objective of the present study was to investigate whether cyclooxygenase-2 (COX-2) is associated with malignancy, and to investigate its molecular mechanisms in human lung cancer tumor malignancy. The present study used RNA interference (RNAi) methodology and celecoxib, a COX-2 inhibitor, to investigate the effect of COX-2 knockdown on the proliferation and invasion abilities of lung cancer cells and the molecular mechanisms involved. Human lung adenocarcinoma A549-si10 and LTEP-A2 cells transfected with a specific small interfering RNA (A549-si10 and LTEP-A2-si10, respectively) grew more slowly compared with parental cell lines and cells transfected with pU6. The colony formation of A549-si10 and LTEP-A2-si10 cells was also reduced. In addition, A549-si10 and LTEP-A2-si10 cells were characterized by decreased metastatic and invasive abilities. The proliferation and invasive potential of parental A549 and LTEP-A2 cells was inhibited following treatment with celecoxib. In vivo, a COX-2 knockdown resulted in a decrease of proliferation and reduction of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and endothelial growth factor receptor (EGFR) expression in A549 xenografts. In conclusion, the present study revealed that COX-2 plays a extremely important role in tumor growth, infiltration and metastasis via the regulation of VEGF, MMP-2 and EGRF expression. Therefore, COX-2 is a potential therapeutic target for lung cancer.

Expression of cyclooxygenase-2 in cervical cancer is associated with lymphovascular invasion

Cyclooxygenase-2 (COX-2) is associated with carcinogenesis and tumor progression. The current study analyzed the effect of COX-2 expression in patients with invasive squamous cervical cancer. Tissue samples from 123 cervical cancer patients were collected for a retrospective analysis using immunohistochemistry (IHC) with an antibody against COX-2. The clinical and survival data of the patients were analyzed. Positive staining for COX-2 (defined as an immunoreactivity score of ≥4) was detected in 28 patients (23%), with significantly higher percentages of staining in tumor cells compared with peritumoral stroma cells (P<0.001). COX-2 expression was significantly associated with lymphovascular space invasion (LVSI; P=0.017). The association of COX-2 expression with LVSI suggests a possible effect of COX-2 on tumor progression in cervical cancer. Further studies including larger patient collectives are required in order to perform analyses of clinical subgroups and patient survival.

Significance of cyclooxygenase 2, EZH-2 polycomb group and p53 expression in actinic keratosis and squamous cell carcinomas of the skin

The development and progression of squamous cell carcinoma (SCC) of the skin is characterized by an accumulation of molecular changes. The aim of this study was to investigate the association of the immunohistochemical expression of cyclooxygenase-2 (COX-2), enhancer of zeste homolog 2 (EZH-2), and p53 in actinic keratosis (AK) and SCC and detect any differences between invasive and preinvasive squamous epidermal lesions. Forty-three cases with AK, 38 with SCC, and 9 with SCC arising on AK (SCC/AK) were studied. For COX-2 immunostaining, weak or no reaction was associated with AK (58.10% of cases), whereas moderate or strong reaction with SCCs (34.2% and 39.5%, respectively). Furthermore, 88.9% of the "mixed" SCC/AK specimens demonstrated moderate reaction (χ2 = 29.924, P < 0.0001). For EZH-2 immunostaining, a weak or no reaction was observed in 62.8% of AK cases, whereas a moderate reaction was observed in 42.1% of SCCs and 77.8% of "mixed" SCC/AK cases (χ2 = 18.91, P = 0.001). Weak immunoreactivity of p53 was associated with AK (58.1%), moderate with SCC (44.7%), and strong with SCC/AK lesions (66.7%) (χ2 = 15.999, P = 0.003). COX-2, p53, but mainly EZH-2 immune expression seems to be strongly associated with the biological potential of squamous epidermal cells and seems to be differentiating SCC by comparison to AK of the skin. The value of the combined expression of these markers is worth being further investigated as an additional tool for diagnostic, prognostic, and possibly, therapeutic use.

Celecoxib radiosensitizes the human cervical cancer HeLa cell line via a mechanism dependent on reduced cyclo-oxygenase-2 and vascular endothelial growth factor C expression

OBJECTIVE

The effects of celecoxib, a selective cyclo-oxygenase-2 (COX-2) inhibitor, on HeLa cervical cancer cell growth and radiosensitivity were investigated.

METHODS

Cytotoxicity was quantified using a 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazolium assay and effects on radiosensitivity were assessed using the lethal dose, quasithreshold dose, fraction surviving after 2 Gy irradiation and the radiosensitization ratio (SER, based on average lethal dose) determined using a single-hit multitarget model.

RESULTS

Celecoxib inhibited HeLa cell proliferation in a concentration- and time-dependent manner, with a half-maximal inhibitory concentration at 72 h of 44 μmol/l. Treatment with 20 μmol/l celecoxib for 72 h before irradiation was associated with an SER of 2.01. The SER of irradiated cells was 2.41 when treated with 40 μmol/l celecoxib before irradiation, 1.89 when treated simultaneously and 1.44 when treated after irradiation. Celecoxib downregulated COX-2 and vascular endothelial growth factor C (VEGF-C) expression evaluated immunohistochemically.

CONCLUSION

Celecoxib pretreatment radiosensitizes HeLa cells via a mechanism dependent on down-regulation of COX-2 and VEGF-C.

Proteomics-based approach to elucidate the mechanism of antitumor effect of curcumin in cervical cancer

Cervical cancer is the second leading cause of cancer death for women in the world. A potential target for preventing and treating cervical cancer is cyclooxygenase-2 (cox-2). Curcumin is an anti-inflammatory agent that is known to have anti-cox-2 activity. In this study we examined the expression of cox-2 in cervical cancer and its precursors by immunohistochemistry. The effect of curcumin in inhibiting cervical cancer cells was determined via 2-dimensional gel electrophoresis, data analysis, and ingenuity pathway analysis. No significant differences in the expression of cox-2 in squamous cell carcinoma, and carcinoma in situ were observed. However, there was a statistically significant difference in the expression of cox-2 in adenocarcinoma in comparison to normal (p value=0.01) and squamous cell carcinoma (p value=0.02) tissues. Proteins associated with cancer and cell cycle were significantly altered in cultured cells. Curcumin may have antitumor effect in cervical cancer.

Cyclooxygenase-2 expression: does it have a probable role in tumorigenesis mechanisms of renal cell carcinoma?

OBJECTIVES

The purpose of this study was to evaluate the correlation between the levels of cyclooxygenase-2 (COX-2) expression with clinicopathologic features and determine the impact on prognosis in patients with renal cell carcinoma (RCC).

METHODS

Expression of COX-2 was evaluated immunohistochemically in RCC tissues from 62 patients who underwent radical nephrectomy between 1996 and 2004. Percentage of COX-2 staining was scored as 0 (negative), 1 (1-24%), 2 (25-49%), 3 (50-74%), and 4 (75-100%). Immunohistochemical COX-2 staining score (ISS) was defined as summation of intensity and percentage of COX-2 staining.

RESULTS

Twenty-seven patients (43.5%) with a median follow-up of 47.8 (25-115) months stained positively for COX-2. COX-2 expression was positive in 37.1%, 50%, and 66.7% of patients with stages 1, 2, and 3, respectively (P = 0.46). Correlation between ISS and pathological stage was statistically significant (P = 0.005). Multivariate regression analysis revealed no clinicopathologic parameter as independent predictors of progression. Kaplan-Meier analysis revealed statistically significant different survival rates in tumor stage, grade, and ISS.

CONCLUSION

Although COX-2 expression is not an independent predictor of progression in patients with RCC, patients with higher ISS values have significantly shorter progression-free survival rates. These results might be important to the clinician because positive COX-2 expression of a certain RCC might necessitate early adjuvant systemic therapy to delay the progression of RCC. For this reason, there is a need for innovative, prospective, and randomized studies in patients with positive COX-2 expression that will display the impact of systemic therapies in these patients.

Cyclooxygenase-2 and Epidermal Growth Factor Receptor Expressions in Different Histological Subtypes of Cervical Carcinomas

This study was designed to evaluate the significance of cyclooxygenase (COX)-2 and epidermal growth factor receptor (EGFR) expression in a series of cervical adenocarcinoma (AC), cervical adenosquamous carcinoma (ASC), and cervical squamous cell carcinoma (SCC). One hundred thirty cases of cervical carcinoma (30 ASC, 50 AC, and 50 SCC) were analyzed for COX-2 and EGFR expressions using specific primary antibodies. Samples were scored semiquantitatively as follows: (-), 0% of immunoreactive cells; (+), <5% of immunoreactive cells; (++), 5% to 50% of immunoreactive cells; and (+++), >50% of immunoreactive cells. The COX-2 expression was more frequently positive than EGFR in all cervical cancers studied. The COX-2 expression was also more prominent in AC than in ASC (P = 0.003). Expression of either COX-2 or EGFR was significantly different when comparing SCC with AC (P < 0.001 and P = 0.04, respectively). There was no significant correlation between COX-2 and EGFR expressions and age at diagnosis, recurrence, distant metastasis, and/or positive status of regional lymph nodes, neither between COX-2 and EGFR coexpression and the clinical data analyzed. Nevertheless, our data support that there are significant differences between EGFR and COX-2 expressions in the 3 different histogenetic types of cervical cancer. Also, in terms of therapeutic strategies, our data can be valuable in the selection of patients eligible to receive specific EGFR/COX-2-targeted therapy.

Effect of a selective nonsteroidal anti-inflammatory drug, celecoxib, on the reproductive function of female mice

BACKGROUND

The aim of the present study was to determine if long-term use of a cyclooxygenase-2 (COX-2) inhibitor affects fertility or ovulation in female mice.

METHODS

Twenty-four female mice, 25 days of age, were given a selective COX-2 inhibitor: 3 mg/kg celecoxib (n = 8), 5 mg/kg celecoxib (n = 8),or placebo (n = 8) in a random fashion. Eight female mice, 10-11 weeks old, given 3 mg/kg celecoxib (n = 4) or placebo (n = 4) were subjected to continuous mating studies.

RESULTS

Results from the 24 mice (n = 8 for each group) showed that oocyte number was not significantly different between female mice treated with either 3 mg/kg or 5 mg/kg celecoxib and placebo (21.4 +/- 2.5, 21.5 +/- 3.3, 23.3 +/- 3.8, respectively). From the continuous mating study, the litter size of female mice treated with celecoxib was not significantly different (8.2 +/- 1.3 pups/litter) compared to those treated with placebo (8.3 +/- 1.2 pups/litter). In addition, female mice treated with celecoxib had an average of 2.8 +/- 0.5 litters in a 12-week period, which was similar to female mice treated with placebo (3.0 +/- 0.8 litters/female).

CONCLUSION

This study suggests that use of low-dose (<or= 5 mg/kg) selective COX-2 inhibitor in a mouse model does not significantly impair the female reproductive function.

Cyclooxygenase-2 (COX-2): first immunohistochemical marker distinguishing early cutaneous melanomas from benign melanocytic skin tumours

We have reported recently that changes in expression level of COX-2 are correlated with development and progression of human melanoma. In this study, we investigated whether the COX-2 expression level might be a useful immunohistochemical marker for distinguishing cutaneous melanomas from benign melanocytic lesions. Up to now, immunohistochemical markers have not ensured satisfactory sensitivity and specificity of differential pathologic diagnosis of melanoma. The expression of COX-2 was determined immunohistochemically in formalin-fixed, paraffin-embedded specimens of 33 early Clark I/II melanomas and 58 naevi. Mean COX-2 expression in melanomas was significantly stronger than in naevi (P approximately 10(-13)). A simple diagnostic algorithm using threshold values of the COX-2 expression level allows for differentiation between early melanomas and naevi with high sensitivity (Se) and specificity (Sp) (for Se between 91 and 100%, Sp values change between 96.5 and 51.7%). Areas under the receiver operating characteristic curves were, respectively, 0.97+/-0.02 and 0.86+/-0.04 for the COX-2 expression in central and border regions of the lesions. For all the melanomas (not only the early ones),the respective areas under the ROC curve values were 0.98+/-0.01 and 0.97+/-0.02. In conclusion, COX-2 is the first immunohistochemical marker that allows the distinguishing of early melanomas from benign melanocytic lesions with both high sensitivity and specificity.

Cyclooxygenase-2 expression in cervical intraepithelial neoplasia III and squamous cell cervical carcinoma, and its correlation with clinicopathologic variables

The objective of the study was to compare cyclooxygenase-2 (COX-2) expression in cervical intraepithelial neoplasia III (CIN III) and squamous cell carcinoma (SCC) of the cervix, and its correlation with clinicopathologic factors of SCC with a review of the available literature. This study included 25 patients with CIN III and 67 patients with stage I-IIa SCC. All patients in the SCC group were treated with radical hysterectomy plus pelvic and para-aortic lymphadenectomy and postoperative chemoradiotherapy based on their histopathologic risk factors. Immunohistochemical analysis was performed on paraffin-embedded sections with COX-2 antibody. COX-2 expression in the SCC group was significantly higher than in the CIN III group (55.2% [37/67] vs 24% [6/25]; P= 0.008). Significantly higher expression of COX-2 was observed in patients with lymphovascular space invasion (LVSI) compared to patients without LVSI (61.9% [34/55] vs 33.3% [3/9]; P= 0.02). Additionally, patients with tumor sizes >4 cm had significantly higher COX-2 expression than patients with tumor sizes <4 cm (65.9% [27/41] vs 39% [10/26] P= 0.028). There was no significant relationship with respect to COX-2 expression and parametrial involvement, lymph node metastasis, recurrences, and survival. In multivariate analysis, LVSI was the only statistically significant determinant for COX-2 expression (P= 0.024; OR = 2.35; 95% CI = 1.1-4.9). Our results and a review of the literature both suggest that COX-2 expression may have a role in the development and progression of CIN III and it is related to some clinicopathologic variables of cervical carcinoma. Further studies are needed to clarify the role of COX-2 inhibitors in the management of CIN and SCC.

Sulindac induces specific degradation of the HPV oncoprotein E7 and causes growth arrest and apoptosis in cervical carcinoma cells

Sulindac, a nonsteroidal anti-inflammatory drug (NSAID), induces growth arrest in HeLa cells and causes strong inhibition of the G1 to S transition of the cell cycle in a concentration-dependent manner. The G1 arrest is preceded by suppression of cyclin E and A, inactivation of cdk2, and the complete loss of the viral oncoprotein E7, despite ongoing HPV transcription. As shown by inhibitors specific for cyclooxygenase (COX) 1 and 2 loss of E7 is COX-independent. Moreover, inhibition of the proteasome activity with MG132 partially blocked the ability of sulindac to suppress E7 suggesting that sulindac induces degradation of E7 by the proteasomal pathway. In addition to inhibiting growth, sulindac strongly induces apoptosis, which can be abrogated by using the general caspase inhibitor zVAD-fmk. Unchanged expression of the pro-apoptotic protein Bax and suppression of the anti-apoptotic molecules Bcl-2 and Bcl-x(L) argues for the engagement of the mitochondrial apoptotic pathway. These results support the notion that sulindac is a potent growth inhibitor and inducer of apoptosis on cervical cancer cells in vitro and may offer new perspectives as a chemopreventive or supplementary anti-cervical cancer drug.

Increased cyclooxygenase-2 expression is correlated with suppressed antitumor immunity in cervical adenocarcinomas

Cyclooxygenase-2 (COX-2) inhibition suppressed the growth of various tumors. The augmentation of antitumor immunity by increasing cytotoxic lymphocytes may be an important mechanism for COX-2 inhibition. Among cervical cancers, adenocarcinomas present more aggressive behavior and overexpressed COX-2. The expression of COX-2 and the CD8+ lymphocyte infiltrations were evaluated in this study by immunohistochemistry. We studied COX-2 expression and CD8+ lymphocyte infiltration in 55 women with cervical adenocarcinomas. COX-2 expression and tumor stromal CD8+ lymphocytes were evaluated by semiquantified methods. Tumor intraepithelial lymphocytes were counted under microscopic field of x200. Correlations between these data and other clinicopathologic features were investigated. Thirty-seven out of 55 (67.3%) cervical adenocarcinomas significantly expressed COX-2. Patients who died within 5 years showed higher percentage of COX-2 expression than survivors (100% vs 58.1%, P < 0.05). Victims also showed lesser intraepithelial CD8+ lymphocyte counts than survived patients (3.4 vs 26.4, P < 0.05). COX-2 expression and tumor intraepithelial lymphocyte count were reversely correlated with each other (correlation index: -0.38, P < 0.01). Up-regulated COX-2 expression and lesser tumor intraepithelial CD8+ lymphocyte count are poor prognostic indicators for cervical adenocarcinoma patients. COX-2 may play an important role in the suppression of host antitumor immunity in cervical adenocarcinomas.

The expression of epidermal growth factor receptor, vascular endothelial growth factor, matrix metalloproteinase-2, and cyclooxygenase-2 in relation to human papilloma viral load and persistence of human papillomavirus after conization with negative margins

The aim of this study was to investigate the correlations between human papillomavirus (HPV) load and vascular endothelial growth factor (VEGF), epidermal growth factor receptor (EGFR), matrix metalloproteinase-2 (MMP-2), and cyclooxygenase-2 (COX-2), and to identify biomarkers that may predict high-risk HPV clearance or persistence after conization with negative margins. The following samples were analyzed: 77 paraffin-embedded specimens from patients with cervical intraepithelial neoplasia (CIN), including 27 CIN 2 conization specimens and 50 CIN 3 conization specimens. Immunohistochemical analysis was performed with antibodies to VEGF, EGFR, MMP-2, and COX-2. Hybrid capture II testing was used to detect HPV DNA. VEGF expression was significantly associated with HPV load (ρ = 0.27186,P= 0.0191), while COX-2 expression was significantly and inversely associated with HPV load (ρ =−0.34309,P= 0.0028). In univariate analysis, HPV load (P= 0.0112) and VEGF expression (P= 0.0274) were significantly associated with high-risk HPV clearance or persistence after conization with negative margins. In multiple regression analysis, high viral load (relative light unit/positive control > 500) and positive VEGF expression were significantly associated with high-risk HPV persistence after conization with negative margins (odds ratio [OR]: 9.915, CI: 1.891–51.994; OR: 6.661, CI: 1.208–36.722, respectively). In conclusion, VEGF expression is related to HPV load, while COX-2 expression is inversely related to HPV load, and immunohistochemical analysis of VEGF expression and HPV viral load are a significant and an independent prognostic indicator of high-risk HPV persistence after conization with negative margins.

Expression of cyclooxygenase-2 related to angiogenesis in uterine cervical cancers

Angiogenesis is essential for development, growth and advancement of solid tumors. Cyclooxygenase (COX)-2 is recognized as an angiogenic factor in various tumors. This prompted us to study the clinical implications of COX-2 expression related to angiogenesis in uterine cervical cancers. There was a significant correlation between microvessel counts and COX-2 levels in uterine cervical cancers. COX-2 localized in the cancer cells, but not in the stromal cells of uterine cervical cancer tissues. COX-2 levels increased with advancement, and the prognosis of the 30 patients with high COX-2 expression in uterine cervical cancers was poor (60%), while the 24-month survival rate of the other 30 patients with low COX-2 expression was 90%. Furthermore, COX-2 levels significantly correlated with VEGF levels in uterine cervical cancers. VEGF associated with COX-2 might work on angiogenesis in advancement. Therefore, long-term administration of COX-2 inhibitors might be effective on the suppression of regrowth or recurrence after intensive treatment for advanced uterine cervical cancers.

Non-steroidal anti-inflammatory drugs to potentiate chemotherapy effects: from lab to clinic

Most solid tumors express the cyclooxygenase-2 (COX-2) protein, a target of NSAIDs. COX-2 overexpression in tumorsis considered a predictor of more advanced stage disease and of worse prognosis in a number of studies investigating solid malignancies. Therefore, NSAIDs are evaluated as anti-cancer drugs. NSAIDs inhibit proliferation, invasiveness of tumors, and angiogenesis and overcome apoptosis resistance in a COX-2 dependent and independent manner. This review will focus on the rationale behind NSAIDs, including selective COX-2 inhibitors, in combination with conventional chemotherapeutic drugs or novel molecular targeted drugs. Studies investigating anti-cancer effects of NSAIDs on cell lines and xenograft models have shown modulation of the Akt, NF-kappaB, tyrosine kinase and the death receptor-mediated apoptosis pathways. COX-2 expression in tumors is not yet used as biomarker in the clinic. Despite the increased risk on cardiovascular toxicity induced by selective COX-2 inhibitors, several ongoing clinical trials are still investigating the therapeutic benefits of NSAIDs in oncology. The anti-tumor effects in these trials balanced with the side effects data will define the precise role of selective COX-2 inhibitors in the treatment of cancer patients.

Elevation of cyclooxygenase-2 is related to lymph node metastasis in adenocarcinoma of uterine cervix

In a previous study, we demonstrated that elevation of COX-2 is significantly associated with lymph node metastasis in squamous cell carcinoma (SCC) of cervix. The main objective of this study is to characterize the relationship between elevation of COX-2 and its possible clinical role in adenocarcinoma (AC) of cervix. Using immunohistochemistry, we examined COX-2 expression levels in 84 patients with AC of uterine cervix [71 ACs, 13 adenosquamous carcinomas (ASCs)]. Elevation of COX-2 was correlated with clinicopathological variables and p53 expression, as detected by immunohistochemistry. Elevation of COX-2 was detected in 13.0% (11 of 84) of the tumors. Elevation of COX-2 was significantly correlated with histologic type (AC 8.5% vs. ASC 38.5%, P=0.011). Both tumor stage and lymph node metastasis were correlated with elevation of COX-2 with a borderline significance (P=0.062 and 0.068, respectively). Elevation of p53 was not associated with elevation of COX-2. The association between lymph node metastasis and elevation of COX-2 was stronger in cases of AC than in cases of ASC (28.4 vs. 4.3%, P=0.023). According to the results of univariate analysis, elevation of COX-2 was significantly associated with decreased overall survival (P=0.003, log-rank test). However, multivariate analyses revealed that only tumor stage was independently associated with overall survival, suggesting that elevation of COX-2 itself may not be an independent prognostic factor. The present study shows that elevation of COX-2 may contribute to lymph node metastasis in AC of uterine cervix. This suggests that the potential therapeutic role of COX-2 inhibitors should be validated, not only in SCC, but also in AC of uterine cervix.

COX-1 and COX-2 expression in stage I and II invasive cervical carcinoma: relationship to disease relapse and long-term survival

COX-1 and COX-2 are members of the cyclooxygenase (COX) family, which influence tumor invasion and apoptosis. The objective of the study was to assess the relationship between COX-1 and COX-2 expression in early-stage disease and subsequent disease relapse and long-term survival. Women with FIGO stage I and II cervical carcinoma, younger than 50 years, treated between 1981 and 1990 were included. COX-1 and COX-2 expressions in the tumors were assessed by immunohistochemistry. COX-1 and COX-2 were expressed in 61% (17/28) and 57% (16/28) of tumors, respectively. COX-1 nonexpressers showed an improved overall survival compared to expressers (log-rank test, P= 0.09). There was no significant difference in the overall survival in COX-2 nonexpressers compared to expressers (P= 0.6). Out of eight women with disease relapse, COX-1 or COX-2 expression was noted in six of eight tumors, and both were expressed in five of eight tumors. Our preliminary data suggest an adverse prognosis with COX-1 expression in early-stage cervical carcinoma and a trend toward COX-1 expression in disease relapse. The association between COX-2 expression and a worse prognosis was not proven in this study.

Expression of cyclooxygenase-2 in benign naevi and during human cutaneous melanoma progression

Cyclooxygenase-2 (COX-2) is an enzyme that plays an important role in the production of prostaglandins. Numerous studies have demonstrated increased levels of COX-2 in human cancers of different types. It is thought that COX-2 may be involved in the development and progression of malignant tumours. However, data on the changes in COX-2 expression during the development and progression of human melanoma are relatively limited. Moreover, the results reported by different groups disagree to a large extent. The aim of this work was to evaluate whether COX-2 protein might be considered a potential molecular marker of melanoma progression. The expression of COX-2 was determined immunohistochemically in formalin-fixed, paraffin-embedded specimens of 64 human melanocytic skin tumours (17 naevi, 36 primary cutaneous melanomas and 11 lymph node melanoma metastases, with six pairs of primary and metastatic lesions obtained from the same patients). It was found that the expression level of COX-2 was dependent on both the stage and histopathological type of the melanoma. Collectively, our data indicate that changes in the expression level of COX-2 are correlated with the development and progression of human melanoma, and imply that the COX-2 protein may be considered a potential prognostic and predictive marker in malignant melanoma.

Prevalence and prognostic significance of COX-2 expression in stage IB cervical cancer

OBJECTIVES

To evaluate the prevalence of cyclooxygenase-2 (COX-2), correlation with various clinicopathologic factors and prognostic significance of COX-2 in stage IB cervical cancer patients.

METHODS

89 paraffin-embedded specimens of patients with stage IB cervical cancer underwent radical hysterectomy and pelvic lymphadenectomy at King Chulalongkorn Memorial Hospital during 1 January 1997-31 December 2002 and were stained with polyclonal goat antiserum against COX-2 using immunohistochemical method. Medical records were reviewed; clinicopathological variables were retrieved and used for analysis.

RESULTS

The prevalence of positive COX-2 expression in stage IB cervical cancer in this study was 49.4%. Positive COX-2 expression in cervical adenocarcinoma was higher than squamous cell carcinoma (86.7% versus 40.6%, P < 0.05) and significantly expressed when lymph node metastasis was presented (100% versus 46.4%, P < 0.05). However, COX-2 expression was possibly associated with parametrial involvement (80% versus 47.6%, P > 0.05). There was no correlation between COX-2 expression and patient's age, tumor size, depth of stromal invasion and lymphovascular space invasion. Five-year disease free survival and 5-year overall survival in patients with positive COX-2 expression were 81% and 98% which were not differed from patients with negative COX-2 expression (92% and 95%, P > 0.05).

CONCLUSIONS

Strong correlation was found in cervical adenocarcinoma and lymph node metastasis. However, COX-2 expression failed to demonstrate as a significant prognostic factor in stage IB cervical cancer.

Cyclooxygenase-2 expression is higher in ovarian cancer tissue adjacent to endometriosis than in ovarian cancer without comorbid endometriosis

OBJECTIVES

The purpose of this study was to examine if COX-2, CK7 and CK20 are involved in the malignant transformation of endometriosis.

METHODS

We compared COX-2, CK7 and CK20 expressions between isolated endometriosis lesions and endometriosis lesions adjacent to ovarian carcinoma and between isolated ovarian carcinoma and ovarian carcinoma with implants of endometriosis. Immunoreactivity was quantified using an immunohistochemical scoring system that corresponds to an image analysis-based system.

RESULTS

There was no difference in COX-2, CK7 and CK20 expressions between the isolated endometriosis lesions and the endometriosis lesions adjacent to ovarian carcinoma. Similarly, CK7 and CK20 were equally expressed between the isolated ovarian carcinoma and the ovarian carcinoma with implants of endometriosis. The COX-2 over-expression rate was greater in ovarian carcinoma that was associated with endometriosis than in isolated ovarian carcinoma (27.8% versus 5.6%, P = 0.083). In endometrioid type ovarian carcinoma, the difference in COX-2 expression was statistically significant (50% versus 0%, P = 0.023).

CONCLUSIONS

COX-2 over-expression may be a result of the malignant transformation of endometriosis to endometrioid type ovarian cancer or may represent an interaction between the two cellular components. With respect to cytokeratins, neither CK7 nor CK20 appear to be involved in the malignant transformation of endometriosis.

Cyclooxygenase-2 and c-erbB-2 expression in uterine cervical neoplasm assessed using tissue microarrays

OBJECTIVES

Cyclooxygenase-2 (COX-2) and c-erbB-2 are involved in the pathogenesis of solid organ tumors. Chemotherapeutic agents targeting COX-2 and c-erbB-2 are used to treat colon and breast cancers. This study evaluated the significance and relationship of COX-2 and c-erbB-2 protein expression in untreated uterine cervical neoplasm.

METHODS

This study included 332 patients with uterine cervical neoplasm. We constructed tissue microarray blocks that included two cores from each donor tumor and immunostained them with primary anti-cyclooxygenase-2 and anti-c-erbB-2 monoclonal antibodies. The clinical features and survival data were compared.

RESULTS

Three hundred and eighteen tumor samples (95.8%) could be interpreted after immunohistochemical staining. COX-2 protein expression was noted in 140 cases of uterine cervical neoplasm (44.0%): In 26.7% of the cervical intraepithelial neoplasia III (16/60 cases), 37.9% of the microinvasive squamous cell carcinoma (39/103 cases), 51.6% of the invasive squamous cell carcinoma (64/124 cases), and 76.2% of the adenocarcinomas (16/21 cases) (P < 0.005). By contrast, except for one case of adenoid cystic carcinoma, none of the uterine cervical neoplasm expressed c-erbB-2 protein. COX-2 protein expression correlated with histology (P < 0.005) and stage (P < 0.05), but was not associated with patient survival.

CONCLUSION

COX-2 may participate in the progression of cervical squamous cell lesions, while the contribution of c-erbB-2 to cervical carcinogenesis is probably small.

Significance of immunohistochemical expression of cyclooxygenase-2 in squamous cell carcinoma of the esophagus

BACKGROUND

The focus of studies on cyclooxygenase-2 (COX-2) have been on its ability to mediate the biological behavior of human tumors including tumorigenesis, tumor progression, apoptosis, and differentiation. The aim of the current study was to elucidate a further finding on the clinicopathologic significance of immunohistochemical expression of COX-2 in esophageal squamous cell carcinoma (ESCC).

METHODS

The immunohistochemical expression of COX-2 was examined for 76 specimens of ESCC and the correlation of COX-2 expression with clinicopathologic features was examined.

RESULTS

Twenty-eight ESCCs (36.8%) had a strong expression of COX-2. The proportion of poorly differentiated SCCs among tumors with a strong expression of COX-2 (42.8%, 12 of 28) was significantly higher than that among tumors with a weak expression of COX-2 (16.7%, 8 of 48; P = .037). The depth of the tumors (P = .003) and the stage of the tumors (P = .015) were advanced significantly more progressively in ESCCs with a strong COX-2 expression. Univariate analysis showed that the prognosis of patients with ESCCs with a strong COX-2 expression was significantly poorer than that of patients with ESCCs with a weak COX-2 expression (P = .017). Multivariate analysis showed that only such tumor-related factors as lymphatic invasion (P = .004), venous invasion (P = .003), and stage of the tumors (P = .021) were found to be associated independently with worse prognosis of the patients with ESCC.

CONCLUSIONS

Strong expression of COX-2 is correlated with tumor progression and poor differentiation in ESCC.

Cyclooxygenase-2 and p53 expression as prognostic indicators in conventional renal cell carcinoma

The aim of this study was to investigate the relationship of cyclooxygenase (COX)-2 and p53 expression with prognosis in patients with conventional renal cell carcinoma (RCC). Formalin-fixed, paraffin-embedded tissue sections of conventional RCC from 92 patients, who had undergone radical nephrectomy, were examined for COX-2 and p53 expression by immunohistochemistry and compared with clinicopathological variables. The COX-2 expression significantly correlated only with tumor size (p=0.049), whereas the p53 expression profoundly correlated with the TNM stage (p=0.024), M stage (p=0.001), and metastasis (synchronous or metachronous; p=0.004). The COX-2 overexpression did not significantly associate with p53 positivity (p=0.821). The survival rate of patients correlated with the p53 expression (p<0.0001) but not with the COX-2 expression (p=0.7506). Multivariate analyses indicated that tumor size, M stage, and p53 expression were independent prognostic factors for cancer-specific survival. The COX-2 expression was not an independent factor. These results show that the increased expression of p53 was associated with metastasis and a worse prognosis in conventional RCC, which suggests that p53 might have played an important role in the progression of conventional RCC. The increased expression of COX-2 was associated only with tumor size, but may not be an important prognostic factor in conventional RCC. No association was observed between COX-2 overexpression and p53 positivity in conventional RCC.

Expression of cyclooxygenase-2 in adenocarcinomas of the uterine cervix and its relation to angiogenesis and tumor growth

OBJECTIVE

The purpose of this study was to evaluate cyclooxygenase (COX)-2 expression in adenocarcinomas of the uterine cervix and its correlation with clinicopathologic features, angiogenesis, and tumor growth.

METHODS

Thirty-nine cases of FIGO clinical stage I and II adenocarcinoma of the uterine cervix were examined by immunohistochemical studies with anti-COX-2. Microvessels were immunohistochemically labeled with an antibody to CD34. Computerized image analysis was used to evaluate microvessel density (MVD). The apoptotic cells were visualized by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) and proliferative cells were visualized by staining with Ki-67 antibody.

RESULTS

Twenty-eight tumors (71.8%) were classified as COX-2 positive. COX-2 expression correlated with FIGO stage (P < 0.01). Tumors expressing COX-2 had a significantly higher MVD and Ki-67 index than those that did not express COX-2 (P < 0.05). However, COX-2 expression did not correlate with the apoptotic index. In univariate long-rank analysis, COX-2 expression, MVD, and FIGO stage were associated with shortened survival. However, FIGO stage and MVD were the only independent prognostic factors by multivariate analysis.

CONCLUSIONS

Our results suggest that COX-2 expression in cervical adenocarcinomas may contribute to tumor progression by increasing angiogenesis and cell proliferation.

Lower expression of cyclooxygenase-2: is it associated with the development of borderline ovarian tumors?

Epithelial ovarian neoplasms can be divided into two major categories on the basis of their pathological and clinical behaviors: invasive ovarian tumors and borderline ovarian tumors. However, neither the etiology nor the pathogenesis of the borderline and invasive epithelial ovarian carcinomas has been understood completely. Borderline tumors are clearly more favaroble in terms of survival. The same pathological types can be seen both in borderline and invasive tumors. However; it is not clear if both diseases is a continuum of the same entity or are independent clinical entities. On the other hand, several in vivo and in vitro studies have demonstrated that overexpression of the cyclooxygenase-2 (COX-2) may have an important role in the development and the aggressive clinical behaviors of different malignancies. Furthermore, some recent studies have also revealed the overexpression of COX-2 in invasive epithelial ovarian carcinomas. In this manuscript, we propose that lower expressions of COX-2 may have a role in the development of borderline ovarian neoplasias, whereas higher levels have a role in the invasive epithelial ovarian cancers and this may be the basis for the clinical difference of both entities. To test this hypothesis; genetic, pathologic and epidemiologic studies may be performed. Patients with borderline tumors should be compared with the invasive counterparts in terms of COX mutations and expressions. Also, epidemiologic studies may reveal the role of COX inhibitors in the ovarian carcinogenesis. If this hypothesis is proven to be true, this may direct the clinicians to use prophylactic NSAIDs with or without combined oral contraceptives especially in high risk patients. Also, this hypothesis may enlight a new gene therapy targeting COX-2 gene in high risk patients for the development of EOC.

Differential cyclooxygenase-2 expression in squamous cell carcinoma and adenocarcinoma of the uterine cervix

PURPOSE

To determine the differential expression of cyclooxygenase-2 (COX-2) in patients with squamous cell carcinoma (SCC) and adenocarcinoma (ADC) of the uterine cervix and the prognostic significance of COX-2 expression in these histologic types.

METHODS AND MATERIALS

A total of 105 International Federation of Gynecology and Obstetrics Stage IIB uterine cervical cancer patients were screened for COX-2 expression immunohistochemically. COX-2 expression was determined in invasive cervical SCC (n = 84) and invasive cervical ADC (n = 21). To determine the clinical significance of COX-2 expression by histologic type, the patients were arbitrarily divided into four groups: SCC/COX-2 negative (n = 64); SCC/COX-2 positive (n = 20); ADC/COX-2 negative (n = 9); and ADC/COX-2 positive (n = 12). The clinical response to treatment, patterns of treatment failure, and survival data by COX-2 expression were compared for these two major histologic types. Univariate and multivariate analyses were performed to identify the prognostic factors influencing survival.

RESULTS

Immunohistochemical examination showed that COX-2 expression was more frequently observed in ADC than in SCC (57% vs. 24%, p = 0.007). Moreover, COX-2 expression was an important predictor of treatment response, irrespective of the histologic type. All COX-2-negative patients achieved complete remission after initial treatment; 17% of SCC patients and 33% of ADC patients with COX-2 expression did not have complete remission after the initial treatment. The incidence of local failure for those with COX-2 expression was significantly greater than for COX-2-negative patients, regardless of histologic type. With a minimal follow-up of 60 months, the overall 5-year actuarial survival rate for SCC and ADC patients was 79% and 62%, respectively (p = 0.05). The 5-year disease-free survival rate for SCC and ADC patients was 73% and 56%, respectively (p = 0.13). Irrespective of the pathologic type, COX-2-positive patients had an unfavorable prognosis. The overall 5-year actuarial survival rate was 57% for COX-2-positive patients and 83% for COX-2-negative patients (p = 0.001). When patients were stratified into the four groups according to histologic type and COX-2 expression status, ADC/COX-2-positive patients had the worst prognosis, with an overall 5-year actuarial survival rate of 49% compared with 78% for ADC/COX-2-negative patients, 62% for SCC/COX-2-positive, and 84% for SCC/COX-2-negative patients (p = 0.007, log-rank test). Irrespective of histologic type, COX-2 expression was an independent prognostic factor by univariate and multivariate analyses.

CONCLUSION

In uterine cervical cancer, COX-2 was expressed in a greater proportion of ADC patients than SCC patients. COX-2 expression was also identified as a major determiner of a poor response to treatment and of an unfavorable prognosis, irrespective of the histologic type, reflecting the importance of the COX-2 protein in the acquisition of biologic aggressiveness and more malignant phenotype or increased resistance to the standard chemotherapy and radiotherapy in both histologic types. Given these observations, we believe that that ADC/COX-2-positive patients might be appropriate candidates for future trials of selective COX-2 inhibitor adjunctive therapy.

Prognostic Role of the Ratio between Cyclooxygenase-2 in Tumor and Stroma Compartments in Cervical Cancer

PURPOSE

The aim of this study was to analyze the clinical role of cyclooxygenase (COX)-2 in a large series of 175 cervical cancer patients.

EXPERIMENTAL DESIGN

Immunohistochemistry was performed on paraffin-embedded sections by using rabbit antiserum against COX-2. The tumor:stroma (T/S) ratio of COX-2 expression was used to define the overall COX-2 content in the tumor.

RESULTS

The T/S COX-2 ratio values ranged from 0.03 to 48.2 (mean +/- SE, 3.7 +/- 0.5). A total of 95 of 175 patients (54.3%) were scored as having a high (>1) T/S COX-2 ratio. In locally advanced cervical cancer patients who underwent neoadjuvant treatment, the percentage of cases showing a high T/S COX-2 ratio was greater in patients who did not respond to treatment (26 of 29 patients, 89.7%) than in patients with a partial (32 of 50 patients, 64.0%) or complete (19 of 44 patients, 43.2%) response (P = 0.0003). When logistic regression was applied, International Federation of Gynecologists and Obstetricians (FIGO) stage (chi(2) = 11.3; P = 0.0008) and T/S COX-2 ratio (chi(2) = 5.3; P = 0.021) retained an independent role in predicting a poor chance of response. Cases with a high T/S COX-2 ratio had a shorter overall survival (OS) [2-year OS, 61%(95% confidence interval 750-83)] than cases with a low T/S COX-2 ratio (2-year OS, 90%; 95% confidence interval, 81-99; P = 0.0001). In multivariate analysis, the status of T/S COX-2 IDV ratio, together with advanced stage, retained an independent negative prognostic role for OS.

CONCLUSIONS

The assessment of COX-2 status in both tumor and stroma compartment could provide valuable information to identify cervical cancer patients endowed with a very poor chance of response to neoadjuvant treatment and unfavorable prognosis.

Tumorigenesis and the angiogenic switch

It has become evident that we cannot understand tumour growth without considering components of the stromal microenvironment, such as the vasculature. At the same time, the tumour phenotype determines the nature of the tumour vasculature. Much research is now devoted to determining the impact of angiogenesis on tumour development and progression, and the reciprocal influences of tumour products on the microvasculature. A more detailed understanding of the complex parameters that govern the interactions between the tumour and vascular compartments will help to improve anti-angiogenic strategies-- not only for cancer treatment, but also for preventing recurrence.