Elevated CAIX Expression is Associated with an Increased Risk of Distant Failure in Early-Stage Cervical Cancer

Formation of morpholine-acetamide derivatives as potent anti-tumor drug candidates: Pharmacological evaluation and molecular docking studies

Heterocyclic amines and acetamide derivatives are known for their chemotherapeutic potential. Hence, in the present study, morpholine was taken as a principal product and novel morpholine derivatives were designed, formulated, characterized, and screened for the mechanism of inhibition of carbonic anhydrase and their anticancer potential. In addition, in vitro inhibition of hypoxia-inducible factor-1 (HIF-1) protein was also investigated. Results revealed that compounds 1c, 1d, and 1h possessed significant inhibitory activities against carbonic anhydrase with IC50 of 8.80, 11.13, and 8.12 μM, respectively. Interestingly, the carbonic anhydrase inhibitory activity of compound 1h was comparable with that of standard acetazolamide (IC50 7.51 μM). The compounds 1h and 1i significantly inhibited the proliferation of ovarian cancer cell line ID8 with IC50 of 9.40, and 11.2 μM, respectively while the standard cisplatin exhibited an IC50 8.50 μM. In addition, compounds 1c, 1b, 1h and 1i also exhibited significant inhibitory effects on HIF-1α. In conclusion, we report first time the biological potential of morpholine based compounds against ovarian cancer and HIF-1α that may serve as lead molecules for drug discovery.

Metabolic Reprogramming in Cancer: Role of HPV 16 Variants

Metabolic reprogramming is considered one of the hallmarks in cancer and is characterized by increased glycolysis and lactate production, even in the presence of oxygen, which leads the cancer cells to a process called “aerobic glycolysis” or “Warburg effect”. The E6 and E7 oncoproteins of human papillomavirus 16 (HPV 16) favor the Warburg effect through their interaction with a molecule that regulates cellular metabolism, such as p53, retinoblastoma protein (pRb), c-Myc, and hypoxia inducible factor 1α (HIF-1α). Besides, the impact of the E6 and E7 variants of HPV 16 on metabolic reprogramming through proteins such as HIF-1α may be related to their oncogenicity by favoring cellular metabolism modifications to satisfy the energy demands necessary for viral persistence and cancer development. This review will discuss the role of HPV 16 E6 and E7 variants in metabolic reprogramming and their contribution to developing and preserving the malignant phenotype of cancers associated with HPV 16 infection.

Microsecond Simulation of the Proteoglycan-like Region of Carbonic Anhydrase IX and Design of Chemical Inhibitors Targeting pH Homeostasis in Cancer Cells

Carbonic anhydrase IX (CAIX) is a membrane-bound enzyme associated with tumor hypoxia and found to be over expressed in various tumor conditions. Targeting CAIX catalytic activity is proven to be efficient modality in modulating pH homeostasis in cancer cells. Proteoglycan-like (PG) region is unique to CAIX and is proposed to serve as an antenna enhancing the export of protons in conjunction with facilitated efflux of lactate ions via monocarboxylate transporters. Moreover, the PG region is also reported to contribute to the assembly and maturation of focal adhesion links during cellular attachment and dispersion on solid supports. Thus, drug targeting of this region shall efficiently modulate pH homeostasis and cell adhesion in cancer cells. As the PG region is intrinsically disordered, the complete crystal structure is not elucidated. Hence, in this study, we intend to sample the conformational landscape of the PG region at microsecond scale simulation in order to sample the most probable conformations that shall be utilized for structure-based drug design. In addition, the sampled conformations were subjected to high-throughput virtual screening against NCI and Maybridge datasets to identify potential hits based on consensus scoring and validation by molecular dynamics simulation. Further, the identified hits were experimentally validated for efficacy by in vitro and direct enzymatic assays. The results reveal 5-(2-aminoethyl)-1,2,3-benzenetriol to be the most promising hit as it showed significant CAIX inhibition at all levels of in silico and experimental validation.

Poor outcome in hypoxic endometrial carcinoma is related to vascular density

Background

Identification of endometrial carcinoma (EC) patients at high risk of recurrence is lacking. In this study, the prognostic role of hypoxia and angiogenesis was investigated in EC patients.

Methods

Tumour slides from EC patients were stained by immunofluorescence for carbonic anhydrase IX (CAIX) as hypoxic marker and CD34 for assessment of microvessel density (MVD). CAIX expression was determined in epithelial tumour cells, with a cut-off of 1%. MVD was assessed according to the Weidner method. Correlations with disease-specific survival (DSS), disease-free survival (DFS) and distant disease-free survival (DDFS) were calculated using Kaplan–Meier curves and Cox regression analysis.

Results

Sixty-three (16.4%) of 385 ECs showed positive CAIX expression with high vascular density. These ECs had a reduced DSS compared to tumours with either hypoxia or high vascular density (log-rank p = 0.002). Multivariable analysis showed that hypoxic tumours with high vascular density had a reduced DSS (hazard ratio [HR] 3.71, p = 0.002), DDFS (HR 2.68, p = 0.009) and a trend for reduced DFS (HR 1.87, p = 0.054).

Conclusions

This study has shown that adverse outcome in hypoxic ECs is seen in the presence of high vascular density, suggesting an important role of angiogenesis in the metastatic process of hypoxic EC. Differential adjuvant treatment might be indicated for these patients.

Heterogenic expression of stem cell markers in patient-derived glioblastoma spheroid cultures exposed to long-term hypoxia

Aim:

To investigate the time profile of hypoxia and stem cell markers in glioblastoma spheroids of known molecular subtype.

Materials & methods:

Patient-derived glioblastoma spheroids were cultured up to 7 days in either 2% or 21% oxygen. Levels of proliferation (Ki-67), hypoxia (HIF-1α, CA9 and VEGF) and stem cell markers (CD133, nestin and musashi-1) were investigated by immunohistochemistry.

Results:

Hypoxia markers as well as CD133 and partially nestin increased in long-term hypoxia. The proliferation rate and spheroid size were highest in normoxia.

Conclusion:

We found differences in hypoxia and stem cell marker profiles between the patient-derived glioblastoma cultures. This heterogeneity should be taken into consideration in development of future therapeutic strategies.

Preclinical effects of CRLX101, an investigational camptothecin-containing nanoparticle drug conjugate, on treating glioblastoma multiforme via apoptosis and antiangiogenesis

Malignant gliomas are difficult to treat in clinical practice. This study was aimed to investigate the preclinical efficacy of CRLX101, an investigational nanoparticle-drug conjugate developed by conjugating camptothecin (CPT) with cyclodextrin-polyethylene glycol, against gliomas. CPT fluorescence was detected across tight-junction barriers and in mouse plasma and brain. Following CRLX101 treatment, CPT was distributed in the cytoplasm of human U87 MG glioma cells. U87 MG cell viability was decreased by CRLX101 and CPT. Moreover, CRLX101 induced less cytotoxicity to human astrocytes compared to CPT. Exposure of U87 MG cells to CRLX101 induced G₂/M cell cycle arrest and apoptosis. Administration of CRLX101 induced apoptosis in mice brain tumor tissues and prolonged the survival rate of mice. In addition, CRLX101 inhibited hypoxia and angiogenesis by suppressing the expression of carbonic anhydrase IX, vascular endothelial growth factor, and CD31 in tumor sections. Taken together, this preclinical study showed that CRLX101 possesses antitumor abilities by inducing cell cycle arrest and apoptosis in glioma cells and inhibiting tumor angiogenesis, thereby prolonging the lifespan of mice bearing intracranial gliomas. These data support further research of CRLX101 in patients with brain tumors.

OncoScape: Exploring the cancer aberration landscape by genomic data fusion

Although large-scale efforts for molecular profiling of cancer samples provide multiple data types for many samples, most approaches for finding candidate cancer genes rely on somatic mutations and DNA copy number only. We present a new method, OncoScape, which exploits five complementary data types across 11 cancer types to identify new candidate cancer genes. We find many rarely mutated genes that are strongly affected by other aberrations. We retrieve the majority of known cancer genes but also new candidates such as STK31 and MSRA with very high confidence. Several genes show a dual oncogene- and tumor suppressor-like behavior depending on the tumor type. Most notably, the well-known tumor suppressor RB1 shows strong oncogene-like signal in colon cancer. We applied OncoScape to cell lines representing ten cancer types, providing the most comprehensive comparison of aberrations in cell lines and tumor samples to date. This revealed that glioblastoma, breast and colon cancer show strong similarity between cell lines and tumors, while head and neck squamous cell carcinoma and bladder cancer, exhibit very little similarity between cell lines and tumors. To facilitate exploration of the cancer aberration landscape, we created a web portal enabling interactive analysis of OncoScape results (http://ccb.nki.nl/software/oncoscape).

A Sensitive IHC Method for Monitoring Autophagy-Specific Markers in Human Tumor Xenografts

Objective. Use of tyramide signal amplification (TSA) to detect autophagy biomarkers in formalin fixed and paraffin embedded (FFPE) xenograft tissue. Materials and Methods. Autophagy marker regulation was studied in xenograft tissues using Amp HQ IHC and standard IHC methods. Results. The data demonstrate the feasibility of using high sensitivity TSA IHC assays to measure low abundant autophagy markers in FFPE xenograft tissue.

Prognostic Significance of Carbonic Anhydrase IX Expression in Cancer Patients: A Meta-Analysis

Hypoxia is a characteristic of many solid tumors and an adverse prognostic factor for treatment outcome. Hypoxia increases the expression of carbonic anhydrase IX (CAIX), an enzyme that is predominantly found on tumor cells and is involved in maintaining the cellular pH balance. Many clinical studies investigated the prognostic value of CAIX expression, but most have been inconclusive, partly due to small numbers of patients included. The present meta-analysis was therefore performed utilizing the results of all clinical studies to determine the prognostic value of CAIX expression in solid tumors. Renal cell carcinoma was excluded from this meta-analysis due to an alternative mechanism of upregulation. 958 papers were identified from a literature search performed in PubMed and Embase. These papers were independently evaluated by two reviewers and 147 studies were included in the analysis. The meta-analysis revealed strong significant associations between CAIX expression and all endpoints: overall survival [hazard ratio (HR) = 1.76, 95% confidence interval (95%CI) 1.58–1.98], disease-free survival (HR = 1.87, 95%CI 1.62–2.16), locoregional control (HR = 1.54, 95%CI 1.22–1.93), disease-specific survival (HR = 1.78, 95%CI 1.41–2.25), metastasis-free survival (HR = 1.82, 95%CI 1.33–2.50), and progression-free survival (HR = 1.58, 95%CI 1.27–1.96). Subgroup analyses revealed similar associations in the majority of tumor sites and types. In conclusion, these results show that patients having tumors with high CAIX expression have higher risk of locoregional failure, disease progression, and higher risk to develop metastases, independent of tumor type or site. The results of this meta-analysis further support the development of a clinical test to determine patient prognosis based on CAIX expression and may have important implications for the development of new treatment strategies.

Overexpression of Carbonic Anhydrase IX is a Dismal Prognostic Marker in Breast Carcinoma in Egyptian Patients

Carbonic anhydrase IX (CAIX) is an enzyme whose expression is very limited in normal tissues and it is highly expressed in various cancers. Therefore, inhibition of CAIX is considered as a promising therapeutic target for the treatment of solid tumors where hypoxic environment has developed. The aim of the current work is to evaluate the immunohistochemical (IHC) expression of CAIX in breast cancer (BC) of Egyptian patients and to investigate the associations of CAIX expression with the standard clinicopathologic features, IHC subtypes of BC, and overall survival. This retrospective study was conducted on 56 archival cases of Egyptian BC patients. Fifty-one of 56 cases (91.1%) showed positive expression of CAIX with cytoplasmic localization, whereas 5 cases (8.9%) showed negative expression. CAIX IHC overexpression is significantly associated with advanced stage and presence of coagulative tumor cell necrosis (P=0.03 and 0.02, respectively). Multivariate analysis revealed Ki67 labeling index and CAIX H-score grouping (P=0.03 and 0.02, respectively) as independent prognostic factors affecting BC patients' overall survival. We concluded that CAIX could play a role in the progression of the studied BC cases. CAIX is a good candidate for target therapy.

Reprogramming energy metabolism and inducing angiogenesis: co-expression of monocarboxylate transporters with VEGF family members in cervical adenocarcinomas

Background

Deregulation of cellular energetic metabolism was recently pointed out as a hallmark of cancer cells. This deregulation involves a metabolic reprogramming that leads to a high production of lactate. Lactate efflux, besides contributing for the glycolytic flux, also acts in the extracellular matrix, contributing for cancer malignancy, by, among other effects, induction of angiogenesis. However, studies on the interplay between cancer metabolism and angiogenesis are scarce. Therefore, the aim of the present study was to evaluate the metabolic and vascular molecular profiles of cervical adenocarcinomas, their co-expression, and their relation to the clinical and pathological behavior.

Methods

The immunohistochemical expression of metabolism-related proteins (MCT1, MCT4, CD147, GLUT1 and CAIX) as well as VEGF family members (VEGF-A, VEGF-C, VEGF-D, VEGFR-1, VEGFR-2 and VEGFR-3) was assessed in a series of 232 cervical adenocarcinomas. The co-expression among proteins was assessed and the expression profiles were associated with patients’ clinicopathological parameters.

Results

Among the metabolism-related proteins, MCT4 and CAIX were the most frequently expressed in cervical adenocarcinomas while CD147 was the less frequently expressed protein. Overall, VEGF family members showed a strong and extended expression with VEGF-C and VEGFR-2 as the most frequently expressed and VEGFR-1 as the less expressed member. Co-expression of MCT isoforms with VEGF family members was demonstrated. Finally, MCT4 was associated with parametrial invasion and HPV18 infection, CD147 and GLUT1 with distant metastasis, CAIX with tumor size and HPV18 infection, and VEGFR-1 with local and lymphnode metastasis.

Conclusions

The results herein presented provide additional evidence for a crosstalk between deregulating cellular energetics and inducing angiogenesis. Also, the metabolic remodeling and angiogenic switch are relevant to cancer progression and aggressiveness in adenocarcinomas.

Expression of hypoxic markers and their prognostic significance in soft tissue sarcoma

Tumor hypoxia is significant in promoting tumor progression and resistance to therapy, and hypoxia-inducible factor 1α (HIF-1α) is essential in the adaptive response of cells to hypoxia. The aim of the present study was to investigate the expression of hypoxic markers and evaluate their prognostic significance in soft tissue sarcoma (STS). A retrospective analysis of 55 patients with STS from Pusan National University Hospital (Busan, Korea) between 1998 and 2007 was conducted, using immunohistochemistry to analyze the expression of HIF-1α, carbonic anhydrase 9 (CA9), glucose transporter-1 (GLUT1) and vascular endothelial growth factor (VEGF). The association between the overexpression of these markers and clinicopathological characteristics, including the overall survival (OS) and progression-free survival (PFS) in cases of STS, were investigated. Overexpression of HIF-1α, CA9, GLUT1 and VEGF was shown in 54.5, 32.7, 52.7 and 25.5% of tumors, respectively, and all exhibited a significant association with high French Federation of Cancer Centers (FNCLCC) grade and high American Joint Committee on Cancer (AJCC) stage. Overexpression of HIF-1α and CA9 was associated with a shorter OS and a shorter PFS. On multivariate analysis, AJCC stage and HIF-1α overexpression had independent prognostic significance. In the group receiving chemotherapy (n=27), HIF-1α overexpression was independently associated with a decreased OS. These results indicate that overexpression of HIF-1α and CA9 is associated with poor prognosis, and that HIF-1α overexpression is an independent unfavorable prognostic factor in STS.

Lactate transporters and vascular factors in HPV-induced squamous cell carcinoma of the uterine cervix

Background

Tumour microenvironment is a fundamental aspect of tumour behaviour, modulating important events as cancer cell migration and invasion, as well as angiogenesis and metastisation. Among other microenvironment features, hypoxia and acidity play important roles in this modulation. As the metabolic reprogramming of cancer cells induces extracellular acidity, which in turn induces angiogenesis, and hypoxia induces both the metabolic reprogramming and angiogenesis, the present study aims to evaluate the immunohistochemical expression of a variety of metabolic and vascular markers as common targets of the hypoxic microenvironment in a series of cervical squamous cells carcinoma, as well as using an in vitro 3D culture model.

Methods

Immunohistochemical expression of MCT1, MCT4, CD147, GLUT1 and CAIX was assessed in a series of 28 chronic cervicitis, 34 LSIL, 29 HSIL, 38 cases of squamous cells carcinoma (SCC), as well as in in vitro 3D culture of keratinocytes expressing HPV genes. Furthermore, VEGF family members’ expression was assessed in the SCC cases. The expression profiles were associated with patients’ clinicopathological parameters.

Results

We found an increase of MCT4 expression along progression to malignancy in cervical samples. Also, MCT4 was associated with CD147 and CAIX expression. VEGF-A expression was more frequently found in cases without MCT1 expression. Both MCT4 and CD147 were more frequently expressed in younger patients at diagnosis while no associations were found between VEGF family and clinicopathological parameters. Finally, we show evidence for the upregulation of MCT4, as well as CD147 and CAIX, after HPV transfection.

Conclusions

The results herein presented point at MCT4 as a promising therapeutic target in squamous cells carcinoma of the uterine cervix. Importantly, we show a possible association between lactate transport and angiogenesis, which should be further explored.

Sulfa drugs as inhibitors of carbonic anhydrase: new targets for the old drugs

Sulfa drugs are well-known antibacterial agents containing N-substituted sulfonamide group on para position of aniline ring (NH₂RSO₂NHR^′). In this study 2,4-dichloro-1,3,5-triazine derivatives of sulfa drugs, sulfamerazine (1b), sulfaquinoxaline (2b), sulfadiazine (3b), sulfadimidine (4b), and sulfachloropyrazine (5b) (1a–5a) were synthesized and characterized. Their carbonic anhydrase inhibition activity was evaluated against bovine cytosolic carbonic anhydrase isozyme II (bCA II). For the sake of comparison the CA inhibition activity of the parent sulfa drugs (1b–5b) was also evaluated. A significant increase in CA inhibition activity of sulfa drugs was observed upon substitution with 2,4-dichloro-1,3,5-triazine moiety. Molecular docking studies were carried out to highlight binding site interactions. ADME properties were calculated to evaluate drug likeness of the compounds.

Recent developments in targeting carbonic anhydrase IX for cancer therapeutics

Carbonic anhydrase IX (CAIX) is a hypoxia-inducible enzyme that is overexpressed by cancer cells from many tumor types, and is a component of the pH regulatory system invoked by these cells to combat the deleterious effects of a high rate of glycolytic metabolism. CAIX functions to help produce and maintain an intracellular pH (pHi) favorable for tumor cell growth and survival, while at the same time participating in the generation of an increasingly acidic extracellular space, facilitating tumor cell invasiveness. Pharmacologic interference of CAIX catalytic activity using monoclonal antibodies or CAIX-specific small molecule inhibitors, consequently disrupting pH regulation by cancer cells, has been shown recently to impair primary tumor growth and metastasis. Many of these agents are in preclinical or clinical development and constitute a novel, targeted strategy for cancer therapy.

Biological predictors of cervical cancer response to radiation therapy

The addition of cisplatin-based chemotherapy to standard radiation therapy reduces the risk of recurrence and disease-related death rates from locally advanced cervical cancers by as much as 50%. However, the absolute gains are relatively small for patients with early tumors, many of whom would have been cured with radiation alone, and recurrence rates are still high for patients who have very large or advanced-stage tumors. As a result, there is a pressing need for more accurate predictors of radiocurability. A variety of types of biomarkers have been shown to correlate with cervical cancer response to radiation therapy. These include traditional clinical and morphologic predictors, non-molecular biomarkers, including hypoxia and fluorodeoxyglucose-positron emission tomography (FDG-PET) avidity, as well as molecular biomarkers, which include single-gene markers or array-based multigene predictors. Multi-gene predictors of response remain immature in cervical cancer, but studies thus far have paved the way for future studies to validate these findings. Methods will need to be standardized and markers will need to be validated on homogeneous patient populations and treatment approaches before they can become useful tools for clinical decision making. In addition, new biomarkers will be of major value only if they add to the predictive value of traditional clinical and morphologic predictors. Ultimately, the most useful biomarkers will identify patients who will benefit from specific molecularly targeted agents in addition to radiation therapy or perhaps identify patient who are at low risk for recurrence, for whom the dose of radiation or chemotherapy can be reduced.

Serum carbonic anhydrase IX and its prognostic relevance in vulvar cancer

INTRODUCTION

Therapeutic options in advanced or recurrent vulvar cancer are limited. The identification of new prognostic factors and markers for therapy stratification is therefore highly desirable. Carbonic anhydrase IX (CAIX) is up-regulated in various solid tumors and a promising new target. We therefore determined CAIX serum concentration and its prognostic relevance in correlation to intratumoral CAIX expression in patients with primary vulvar cancer.

METHODS

Thirty-one serum samples of patients with primary vulvar cancer were prospectively collected before surgery and analyzed for CAIX by enzyme-linked immunosorbent assay. In addition, intratumoral CAIX expression was determined by immunohistochemistry and correlation with serum CAIX and clinicopathological factors, and outcome was analyzed.

RESULTS

Preoperative serum concentration of CAIX ranged between 56 and 879 pg/mL (median, 147 pg/mL; mean, 237.29) and was significantly higher in patients with high intratumoral expression (median, 269 pg/mL vs 126 pg/mL, P = 0.03). High serum CAIX was not associated with any of the analyzed clinicopathological parameters. However, disease-free survival was shorter in patients with high preoperative serum CAIX (above median; P = 0.012). By immunohistochemistry, 26% of the tumors showed a moderate or strong expression of CAIX, whereas 74% showed weak or no expression. High intratumoral expression of CAIX was also associated with unfavorable disease-free survival (P = 0.043).

CONCLUSIONS

Carbonic anhydrase IX serum concentration is higher in patients with high intratumoral expression, and elevated preoperative serum values are associated with unfavorable prognosis. Serum CAIX might therefore be an easily assessable marker to stratify patients for adjuvant therapy and potentially monitor response. Carbonic anhydrase IX is differentially expressed in vulvar cancer and potentially associated with negative outcome.

Carbonic anhydrase IX in tumor tissue and sera of patients with primary cervical cancer

Background

Carbonic anhydrase IX (CAIX) is a membranous expressed metalloenzyme involved in pH homeostasis and cell adhesion. The protein is overexpressed in a variety of tumors and potentially associated with negative outcome. This study was designed to investigate the prognostic role of CAIX in serum and tumor tissue of patients with primary cervical cancer.

Methods

Tumor samples of 221 consecutive patients with primary cervical cancer who underwent surgery between 1993 and 2008 were analyzed for CAIX expression by immunohistochemistry. Additionally, preoperative serum CAIX concentrations were determined by ELISA in a subset of patients. Correlation with intratumoral CAIX expression as well as clinicopathological factors and outcome was analyzed.

Results

CAIX expression was observed in 81.9% of the tumor specimens; 62.0% showed a moderate or strong staining intensity. Moderate/strong expression was associated with squamous histology (p = 0.024), advanced tumor stage (p = 0.001), greater invasion depth (p = 0.025), undifferentiated tumor grade (p < 0.001) and high preoperative SCC-Ag values (p = 0.042). Furthermore patients with moderate/strong intratumoral CAIX expression had a higher number of metastatic lymph nodes compared to those with none/weak intratumoral expression levels (p = 0.047) and there was a non-significant association between high intratumoral CAIX expression and shorter survival (p = 0.118). Preoperative serum concentrations of CAIX ranged between 23 and 499 pg/mL and did not correlate with intratumoral expression or other clinicopathological variables.

Conclusion

CAIX is associated with advanced tumor stages and lymph node metastases in cervical cancer, potentially representing a new target in this disease. In contrast to other epithelial cancers we could not observe a correlation between serum CAIX and its intratumoral expression.

Prognostic relevance of carbonic anhydrase-IX in high-risk, early-stage cervical cancer: a Gynecologic Oncology Group study

OBJECTIVES

This study aimed to determine whether carbonic anhydrase-IX (CA-IX) was associated with progression-free survival (PFS) and overall survival (OS) in women with high-risk, early-stage cervical cancer treated with adjuvant pelvic radiotherapy with or without radiosensitizing chemotherapy.

METHODS

CA-IX expression was detected using an immunohistochemistry assay and categorized as low when <or=80% of tumor cells exhibited CA-IX staining and high when >80% tumor cells display CA-IX staining. Associations between CA-IX expression and clinical characteristics, angiogenesis marker expression, and clinical outcome were evaluated.

RESULTS

High CA-IX expression was observed in 35/166 (21.1%) of cases. CA-IX expression was not associated with age, race, stage, cell type, grade, positive margins, parametrial extensions, positive lymph nodes, or lymphovascular space invasion but was associated with tumor size categorized as <2 , 2-2.9 , or >or=3 cm (high expression: 4.7% vs. 23.2% vs. 32.5%, P=0.003) and cervical invasion confined to the inner two-thirds compared with the outer third of the cervix (high expression: 6.1% vs. 23.7%, P=0.028). CA-IX expression was not associated with immunohistochemical expression of p53, CD31, CD105, thrombospondin-1, or vascular endothelial growth factor-A. Women with high versus low CA-IX expression had similar PFS (P=0.053) and significantly worse OS (P=0.044). After adjusting for prognostic clinical covariates, high CA-IX expression was an independent prognostic factor for PFS (hazard ratio [HR]=2.12; 95% confidence interval [CI]=1.13-3.95; P=0.019) and OS (HR=2.41; 95% CI=1.24-4.68; P=0.009).

CONCLUSIONS

Tumor hypoxia measured by immunohistochemical expression of CA-IX is an independent prognostic factor for both PFS and OS in high-risk, early-stage cervical cancer.