VEGF, flt-1, and KDR/flk-1 as prognostic indicators in endometrial carcinoma

Anti-tumor effects of vascular endothelial growth factor/vascular endothelial growth factor receptor binding domain-modified chimeric antigen receptor T cells

BACKGROUND AIMS

The vascular endothelial growth factor (VEGF)/vascular endothelial growth factor receptor (VEGFR) signaling pathway plays an important role in angiogenesis and lymphangiogenesis, which are closely related to tumor cell growth, survival, tissue infiltration and metastasis. Blocking/interfering with the interaction between VEGF and VEGFR to inhibit angiogenesis/lymphangiogenesis has become an important means of tumor therapy.

METHODS

Here the authors designed a novel chimeric antigen receptor (CAR) lentiviral vector expressing the VEGF-C domain targeting both VEGFR-2 and VEGFR-3 (VEGFR-2/3 CAR) and then transduced CD3-positive T cells with VEGFR-2/3 CAR lentivirus.

RESULTS

After co-culturing with target cells, VEGFR-2/3 CAR T cells showed potent cytotoxicity against both VEGFR-2- and VEGFR-3-positive breast cancer cells, with increased simultaneous secretion of interferon gamma, tumor necrosis factor alpha and interleukin-2 cytokines. Moreover, CAR T cells were able to destroy the tubular structures formed by human umbilical vein endothelial cells and significantly inhibit the growth, infiltration and metastasis of orthotopic mammary xenograft tumors in a female BALB/c nude mice model.

CONCLUSIONS

The authors' results indicate that VEGFR-2/3 CAR T cells targeting both VEGFR-2 and VEGFR-3 have significant anti-tumor activity, which expands the application of conventional CAR T-cell therapy.

Bioinformatic analysis linking genomic defects to chemosensitivity and mechanism of action

A joint analysis of the NCI60 small molecule screening data, their genetically defective genes, and mechanisms of action (MOA) of FDA approved cancer drugs screened in the NCI60 is proposed for identifying links between chemosensitivity, genomic defects and MOA. Self-Organizing-Maps (SOMs) are used to organize the chemosensitivity data. Student's t-tests are used to identify SOM clusters with enhanced chemosensitivity for tumor cell lines with versus without genetically defective genes. Fisher's exact and chi-square tests are used to reveal instances where defective gene to chemosensitivity associations have enriched MOAs. The results of this analysis find a relatively small set of defective genes, inclusive of ABL1, AXL, BRAF, CDC25A, CDKN2A, IGF1R, KRAS, MECOM, MMP1, MYC, NOTCH1, NRAS, PIK3CG, PTK2, RPTOR, SPTBN1, STAT2, TNKS and ZHX2, as possible candidates for roles in chemosensitivity for compound MOAs that target primarily, but not exclusively, kinases, nucleic acid synthesis, protein synthesis, apoptosis and tubulin. These results find exploitable instances of enhanced chemosensitivity of compound MOA's for selected defective genes. Collectively these findings will advance the interpretation of pre-clinical screening data as well as contribute towards the goals of cancer drug discovery, development decision making, and explanation of drug mechanisms.

The Role of VEGF Receptors as Molecular Target in Nuclear Medicine for Cancer Diagnosis and Combination Therapy

Simple Summary

The rapid development of diagnostic and therapeutic methods of the cancer treatment causes that these diseases are becoming better known and the fight against them is more and more effective. Substantial contribution in this development has nuclear medicine that enables very early cancer diagnosis and early start of the so-called targeted therapy. This therapeutic concept compared to the currently used chemotherapy, causes much fewer undesirable side effects, due to targeting a specific lesion in the body. This review article discusses the possible applications of radionuclide-labelled tracers (peptides, antibodies or synthetic organic molecules) that can visualise cancer cells through pathological blood vessel system in close tumour microenvironment. Hence, at a very early step of oncological disease, targeted therapy can involve in tumour formation and growth.

Abstract

One approach to anticancer treatment is targeted anti-angiogenic therapy (AAT) based on prevention of blood vessel formation around the developing cancer cells. It is known that vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptors (VEGFRs) play a pivotal role in angiogenesis process; hence, application of angiogenesis inhibitors can be an effective approach in anticancer combination therapeutic strategies. Currently, several types of molecules have been utilised in targeted VEGF/VEGFR anticancer therapy, including human VEGF ligands themselves and their derivatives, anti-VEGF or anti-VEGFR monoclonal antibodies, VEGF binding peptides and small molecular inhibitors of VEGFR tyrosine kinases. These molecules labelled with diagnostic or therapeutic radionuclides can become, respectively, diagnostic or therapeutic receptor radiopharmaceuticals. In targeted anti-angiogenic therapy, diagnostic radioagents play a unique role, allowing the determination of the emerging tumour, to monitor the course of treatment, to predict the treatment outcomes and, first of all, to refer patients for AAT. This review provides an overview of design, synthesis and study of radiolabelled VEGF/VEGFR targeting and imaging agents to date. Additionally, we will briefly discuss their physicochemical properties and possible application in combination targeted radionuclide tumour therapy.

Angiogenesis in endometrial carcinoma: Therapies and biomarkers, current options, and future perspectives

Endometrial carcinoma is the most common gynecologic malignancy and the fourth most prevalent cancer in women in the modern world. Despite a relatively high chance of surgical cure, for patients with advanced or recurrent disease there are few therapeutic options. Angiogenesis has been extensively studied ever since vascular endothelial growth factor (VEGF) was discovered in the 1980s. Several clinical trials of anti-angiogenic therapy in endometrial carcinoma have been conducted, with mixed results, and many researchers have tried to determine prognostic and therapeutic biomarkers. Recent trials, which shed new light on possible treatment biomarkers and efficacious combination therapies, are reviewed in this text. While we are still far from effectively tailoring anti-angiogenic treatment to each patient, these data have provided valuable insight and have put us on track for the discovery of novel opportunities for angiogenesis therapy in endometrial carcinoma.

Angiogenesis in gynecological cancers and the options for anti-angiogenesis therapy

Angiogenesis is required in cancer, including gynecological cancers, for the growth of primary tumors and secondary metastases. Development of anti-angiogenesis therapy in gynecological cancers and improvement of its efficacy have been a major focus of fundamental and clinical research. However, survival benefits of current anti-angiogenic agents, such as bevacizumab, in patients with gynecological cancer, are modest. Therefore, a better understanding of angiogenesis and the tumor microenvironment in gynecological cancers is urgently needed to develop more effective anti-angiogenic therapies, either or not in combination with other therapeutic approaches. We describe the molecular aspects of (tumor) blood vessel formation and the tumor microenvironment and provide an extensive clinical overview of current anti-angiogenic therapies for gynecological cancers. We discuss the different phenotypes of angiogenic endothelial cells as potential therapeutic targets, strategies aimed at intervention in their metabolism, and approaches targeting their (inflammatory) tumor microenvironment.

TNFAIP8L1 and FLT1 polymorphisms alter the susceptibility to cervical cancer amongst uyghur females in China

TNFAIP8L1 and FLT1 play critical roles in the occurrence and development of tumors, but no in-depth studies have been carried out in cervical cancer. The present study aims to research the correlation between polymorphisms of these two genes and the risk of cervical cancer in the Uygur women. The study involved 342 cervical cancer patients and 498 healthy women. Five single nucleotide polymorphisms (SNPs) from the TNFAIP8L1 gene and the FLT1 gene were selected and genotyped. Odds ratio and 95% CIs were calculated by logistic regression analysis to evaluate the correlation between SNPs and cervical cancer risk. The alleles rs9917028-A (P=0.032), rs10426502-A (P=0.007), and rs1060555-G (P=0.026) of TNFAIP8L1 were associated with a decreased risk of cervical cancer. In the multiple genetic models, these three SNPs were also associated with the risk of cervical cancer. The stratified analysis showed that TNFAIP8L1-rs10426502, -rs1060555, and FLT1-rs9513111 were associated with a decreased risk of cervical cancer amongst people older than 43 years. Moreover, the haplotypes AG (P=0.007) and GC (P=0.026) of linkage disequilibrium block rs10426502|rs1060555 in TNFAIP8L1 were significantly associated with an increased risk of cervical cancer. Our results suggested that the relationships between TNFAIP8L1 and FLT1 polymorphisms and the risk of cervical cancer amongst Uyghur females.

Bladder cancer cells interact with vascular endothelial cells triggering EGFR signals to promote tumor progression

Although important progress has been made in elucidating the role of the tumor microenvironment in the development of bladder cancer, little is currently known regarding the interactions with vascular endothelial cells (ECs) that promote cancer progression. In the present study, it is reported that epidermal growth factor receptor ligands induced by the upregulation of vascular endothelial growth factor (VEGF)-A and VEGF-C via the VEGF receptor (R)2/nuclear factor-κB signaling pathway in ECs, may trigger EGFR signaling in bladder cancer cells and promote bladder cancer progression. Furthermore, the interaction between bladder cancer cells and ECs enhanced EC recruitment though the CXCL1/CXCL5/CXCL8-CXCR2 pathway. Western blotting was used to evaluate the presence of VEGFR, EGFR and nuclear factor-κB, and reverse transcription-quantitative polymerase chain reaction was used to evaluate the expression of VEGFR ligands and EGFR ligands. The present results indicate the mechanism by which the indirect interplay between bladder cancer cells and vascular ECs promotes cancer progression, through the VEGFR2 signaling pathway in vascular ECs and through the EGFR signaling pathway in bladder cancer cells.

Endometrial Carcinoma: Specific Targeted Pathways

Endometrial cancer (EC) is the most common gynecologic malignancy in the western world with more than 280,000 cases per year worldwide. Prognosis for EC at early stages, when primary surgical resection is the most common initial treatment, is excellent. Five-year survival rate is around 70 %.Several molecular alterations have been described in the different types of EC. They occur in genes involved in important signaling pathways. In this chapter, we will review the most relevant altered pathways in EC, including PI3K/AKT/mTOR, RAS-RAF-MEK-ERK, Tyrosine kinase, WNT/β-Catenin, cell cycle, and TGF-β signaling pathways. At the end of the chapter, the most significant clinical trials will be briefly discussed.This information is important to identify specific targets for therapy.

The significance of markers in the diagnosis of endometrial cancer

Endometrial cancer is one of the most common cancers experienced by women throughout the world. It is also the most common malignancy within the female reproductive system, representing 37.7% of all disorders. The incidence increases with age, and is diagnosed most frequently in women between 45 and 65 years old. In the last few years, numerous studies have been performed to identify tumour biomarkers. Biomarkers include not only protein routinely used as tumour markers but also genes and chromosomes. The limiting factor in the use of markers in the diagnosis of endometrial cancer is their lack of specificity. However, specific markers for endometrial cancer are the subject of much research attention. Although moderately elevated levels of markers are present in a number of inflammatory or non-malignant diseases, significantly increased levels of markers indicate the development of cancer. Recently, research has been focused on the identification of molecular changes leading to different histological subtypes of endometrial cancer. In this paper the authors reviewed several currently investigated markers. Progress in these investigations is very important in the diagnostics and treatment of endometrial cancer. In particular, the identification of novel mutations and molecular profiles should enhance our ability to personalise adjuvant treatment with genome-guided targeted therapy.

Prognostic significance of VEGFR1/Flt-1 immunoexpression in colorectal carcinoma

Colorectal carcinoma (CRC) is a major cause of morbidity and mortality. Vascular endothelial growth factor 1/Fms-like tyrosine kinase 1 (VEGFR1/Flt-1) regulates monocyte migration, recruits endothelial cell progenitors, increases the adhesive properties of natural killer cells and induces of growth factors. Flt-1 is expressed on tumour cells and has been implicated in tumour growth and progression. The objective of this study is to address the relation of Flt-1 expression to tumour prognostication. Paraffin blocks from 143 primary CRC and 48 regional nodal metastases were retrieved from the archives of the Department of Pathology at King Abdulaziz University. Tissue microarrays were designed and constructed. Immunohistochemistry for Flt-1 was performed. Staining intensity and extent of staining were assessed and combined. Results were dichotomised as low expression and high expression. Flt-1 was overexpressed in primary tumours and nodal metastasis (p < 0.001 and 0.001) with no difference between primary and nodal metastasis (p = 0.690). Flt-1 immunoexpression was not associated with the clinicopathological parameters. Flt-1 overexpression was an independent predictor of positive margin status, positive lymphovascular invasion and local disease recurrence (p < 0.001, p < 0.001 and p = 0.003, respectively). Flt-1 was not associated with survival (log-rank = 0.003, p = 0.959). Flt-1 was overexpressed in primary CRC and their nodal metastases. Flt-1 expression was an independent predictor of margin status, lymphovascular invasion and local disease recurrence. Therefore, expression profiling of Flt-1 seems to have a prognostic potential in CRC. However, to elucidate the association of overexpression of Flt-1 with tumour characteristics and prognostication, more in vivo and in vitro molecular investigations are recommended.

Endoglin, VEGF, and its receptors in predicting metastases in endometrial carcinoma

Preoperative evaluation of the risk for metastases in endometrial carcinoma is challenging. The growth of new vessels, angiogenesis, is important for tumor growth and purported to be involved in the metastatic process. The aim of this study was to evaluate the significance of preoperative serum levels and immunohistochemical expression of angiogenic markers in predicting a metastasized disease. Preoperative sera from 98 consecutive women presenting with endometrial carcinoma were collected. Serum concentrations of VEGF, sFLT1, and CD105 were assessed by enzyme-linked immunosorbent assay (ELISA). Immunohistochemistry was used to assess the expression of CD105, VEGF, FLT1, and KDR. The results were correlated to the presence of metastases, presence of deep (≥50%) myometrial invasion, and the histological grade of the tumor. Tumors with other than endometrioid histology were excluded. Of the 80 evaluable patients, 11 had a metastasized disease. The serum concentration of VEGF was higher in the group with metastases than in the group without metastases (median [range], 743 pg/mL [546-1,183 pg/mL] vs. 383 pg/mL [31-1,524 pg/mL], p < 0.001, respectively). In the multivariable analysis, the concentration of VEGF was the sole independent, albeit weak predictive factor for the presence of metastases (odds ratio, 1.004, 95% confidence interval, 1.002-1.007; p = 0.001). The immunohistochemical expression of the markers was not associated with any of the clinicopathological features of the tumors. The results of the present study suggest that preoperative serum VEGF concentration correlates with the presence of metastases in endometrioid endometrial carcinoma.

Active immunotherapy for mouse breast cancer with irradiated whole-cell vaccine expressing VEGFR2

As tumor-associated antigens are not well characterized for the majority of human tumors, polyvalent vaccines prepared with whole-tumor antigens are an attractive approach for tumor vaccination. Vascular endothelial growth factor receptor-2 (VEGFR2), as a model antigen with which to explore the feasibility of immunotherapy, has shown great promise as a tumor vaccine. However, the efficacy of immunotherapy is often not ideal when used alone. In this study, we explored the therapeutic efficacy of an irradiated AdVEGFR2-infected cell vaccine-based immunotherapy in the weakly immunogenic and highly metastatic 4T1 murine mammary cancer model. An adenovirus encoding the VEGFR2 gene (AdVEGFR2) was constructed. Lethally irradiated, virus-infected 4T1 cells were used as vaccines. Vaccination with lethally irradiated AdVEGFR2-infected 4T1 cells inhibited subsequent tumor growth and pulmonary metastasis compared with challenge inoculations. Angiogenesis was inhibited, and the number of CD8+ T lymphocytes was increased within the tumors. Antitumor activity was also caused by the adoptive transfer of isolated spleen lymphocytes. In vitro, the expression of HMGB1 and HSP70 in the AdVEGFR2‑infected 4T1 cells was increased, and was involved in the activation of tumor antigen-specific T-cell immunity. Our results indicate that the immunotherapy based on irradiated AdVEGFR2-infected whole-cancer cell vaccines may be a potentially effective strategy for 4T1 cancer treatment.

Prognostic value of tgfb1 protein in endometrioid adenocarcinoma

BACKGROUND

Angiogenesis is a prerequisite for tumour development, progression and metastasis; however, its underlying molecular mechanisms in endometrial carcinoma are poorly understood.

DESIGN

In this study, the mRNA and protein expression profiles of two key regulators of angiogenesis, vascular endothelial growth factor (VEGF) and transforming growth factor beta-1 (TGFB1), were evaluated by real-time PCR and western blot analysis in 23 endometrial cancer tissue-paired specimens (malignant vs. adjacent normal tissues). We aimed to investigate whether VEGF and TGFB1 serve as markers of the malignant transformation of the endometrium and whether VEGF or TGFB1 expression can constitute a useful prognostic marker of survival in patients with endometrial carcinoma.

RESULTS

Tissue-pair analysis revealed VEGF transcriptional up-regulation and TGFB1 mRNA down-regulation as the most frequent transcriptional features. VEGF and TGFB1 mRNA were positively correlated (P < 0·001). VEGF protein levels were higher in endometrioid-type tissue pairs (P = 0·047). TGFB1 protein and mRNA levels were negatively correlated (P = 0·042). TGFB1 protein expression was related to survival only in patients with endometrioid adenocarcinoma (P = 0·045).

CONCLUSIONS

Tissue-pair mRNA and protein analysis reveals VEGF transcriptional up-regulation and TGFB1 down-regulation that are correlated with the malignant transformation of the endometrium, while post-transcriptional mechanisms control VEGF and TGFB1 protein. TGFB1 protein demonstrated a prognostic value only in endometrioid adenocarcinoma.

A phase II evaluation of aflibercept in the treatment of recurrent or persistent endometrial cancer: a Gynecologic Oncology Group study

OBJECTIVES

Aflibercept targets vascular endothelial growth factor and placental growth factor. We evaluated activity and toxicity of aflibercept in recurrent/persistent endometrial cancer patients. Biomarkers and association with clinical characteristics and outcome were explored.

METHODS

Eligible patients had measurable disease; 1-2 prior cytotoxic regimens; performance status 0-2. Aflibercept 4 mg/kg IV q14 days (28-day cycles) was administered until disease progression or prohibitive toxicity. Primary endpoints were the proportion of patients with progression-free survival at 6 months (PFS6) and tumor response rate. A flexible two-stage group sequential design to detect 20% increases in the proportion of patients responding or enduring PFS6 with 90% power (α=10%) was employed.

RESULTS

Forty-nine patients were enrolled; five were excluded: wrong primary (2), second primary (1), wrong cell type (1); and never treated (1). Median age was 64 (range 48-83). Eighteen patients (41%) had two prior regimens; 27 (61%) had prior radiation. The PFS6 rate was 41%; three patients (7%, 90% CI: 2-17) had partial response. Of note, 10 patients (23%) met the PFS6 endpoint without starting a subsequent therapy; the remaining eight patients discontinued therapy for toxicity and started another therapy before 6 months elapsed. Median PFS and overall survival were 2.9 months and 14.6 months, respectively. Significant grade 3/4 toxicities were: cardiovascular (23%/5%), constitutional (7%/0), hemorrhage (2%/5%), metabolic (7%/2%), and pain (18%/0). Two treatment-related deaths were recorded: GI perforation (1), and arterial rupture (1). FGF1 expression was associated with response.

CONCLUSIONS

Aflibercept met pretrial activity parameters, but was associated with significant toxicity at this dose and schedule in this population.

Promising novel therapies for the treatment of endometrial cancer

OBJECTIVES

To discuss the novel agents which are being developed for the treatment of advanced and recurrent endometrial carcinoma and to review other molecular targets that may be interesting in the treatment of this disease. While the majority of women with endometrial cancer enjoy a relatively good prognosis, the options for those women who suffer from a disease recurrence are limited and there is a need to identify novel agents.

METHODS

A review of clinical trials of novel therapeutic agents and their molecular targets is provided. In addition, a review of the current literature on other potential molecular targets for endometrial cancer was performed.

RESULTS

Several phase II trials of novel agents, both alone and in combination with traditional cytotoxic chemotherapy, have been completed or are nearing completion. It appears that the targeted agents may have the most efficacy in combination with cytotoxic chemotherapy or in a multi-targeted agent approach.

CONCLUSIONS

Chemotherapy offers the opportunity for a meaningful response rate in women with endometrial cancer, but the responses are often short lived and cure is uncommon in the setting of recurrent disease. The recent increase in molecular targets has led to the availability of many novel therapies. Determining how these agents are to be used, alone or in combination with "standard" therapies, needs to be defined and translational studies are needed to develop rational combinations of these novel agents before we can move into clinical trials.

Current challenges in clinical management of endometrial cancer

Endometrial cancer remains a management challenge. Improved understanding of the mechanisms of carcinogenesis may enable better understanding of biologic behavior and guide therapy. Improvements in diagnostic imaging, radiation delivery systems, and systemic therapies potentially can improve outcomes while minimizing morbidity. Novel strategies for screening and prevention also hold promise for reducing incidence and mortality of this disease.

Prognostic significance of VEGF expression in patients with bulky cervical carcinoma undergoing neoadjuvant chemotherapy

Background

The prediction of response to treatment would be valuable for managing cervical carcinoma with neoadjuvant chemotherapy.

Methods

To this end, the expression of VEGF was analyzed by immunohistochemistry using paraffin-embedded pre-treatment cervical biopsy tissues. This study included 29 patients with bulky IB to IIA cervical squamous cell carcinoma treated with neoadjuvant chemotherapy.

Results

Fifteen (51.7%) of 29 patients were scored as VEGF-positive. Response to chemotherapy (complete response or residual tumor with less than 3 mm stromal invasion) was observed in eight patients (27.6%), and it was negatively associated with VEGF expression (P = 0.009). With logistic regression analysis, VEGF positivity continued to be an independent predictor for poor response (P = 0.032). In addition, the progression-free survival rate was significantly lower in patients with VEGF-positive tumors (P = 0.033).

Conclusion

Pretreatment assessment of VEGF expression may provide additional information for identification of patients with cervical cancer who had a low likelihood of response to neoadjuvant chemotherapy and an unfavorable prognosis.

Comparison of serum VEGF and its soluble receptor sVEGFR1 with serum cell-free DNA in patients with breast tumor

BACKGROUND

The observed elevated levels of vascular endothelial growth factor (VEGF), its soluble receptor (sVEGFR1) and cell-free DNA (cfDNA) in the serum of patients with various cancers have attracted much attention to the possibility of using these agents as biomarkers for cancers. We wanted to find out whether VEGF, VEGFR1 or cfDNA is a biomarker for breast cancer.

METHODS

In this study, we used enzyme-linked immunosorbent assay (ELISA) to examine the levels of serum VEGF and VEGFR1 in 23 patients with benign tumors, 19 patients with breast cancer and 32 age-matched healthy females. The levels of circulating cell-free DNA were measured using TaqMan real-time PCR analysis for the glyceraldehydes 3 phosphate dehydrogenase gene (GAPDH), We compared the serum levels of VEGF and its soluble receptors with those of the cell-free serum DNA.

RESULTS

In terms of serum levels of either VEGF or its soluble receptors VEGFR1, we found no significant difference between healthy individuals and women with benign breast tumors and breast cancer. However, there was a significant increase in circulating cell-free DNA in women with both benign and malignant breast tumors when compared with the corresponding healthy control group. We also found a significant negative correlation between VEGF and its soluble receptor VEGFR1 (r=-0.328 and p=0.004), and a significant positive correlation between VEGF and cell-free serum DNA (r=0.241 and p=0.033).

CONCLUSIONS

We can conclude that quantitative analysis of circulating cell-free DNA in serum may provide molecular biological understanding of breast tumors in women. It would also suggest that serum levels of VEGF and VEGFR1 have less significance.

Expression of vasohibin as a novel endothelium-derived angiogenesis inhibitor in endometrial cancer

We have previously reported on vasohibin as a novel endothelium-derived vascular endothelial growth factor (VEGF)-inducible inhibitor of angiogenesis. The aim of our present study was to define the role of vasohibin in endometrioid endometrial adenocarcinoma. We collected 78 sections of endometrial carcinoma for assessment using immunohistochemistry. Twenty-seven were well differentiated (G1), 25 were moderately differentiated (G2), and 26 were poorly differentiated endometrioid adenocarcinomas (G3). We also included 12 sections of normal cyclic endometria, six of which were in the proliferative phase and six were in the secretory phase. We investigated the expression of vasohibin, and compared it to VEGF receptor-2 (VEGFR-2: KDR/flk-1), CD34, Ki-67, VEGF-A, and D2-40 (as a lymphatic vessel marker). We assessed the ratio of vasohibin- and VEGFR-2-positive vessels in the stroma of endometrial carcinoma. Immunohistochemical assessment was classified as negative or positive based on staining intensity. Vasohibin was selectively expressed on vascular endothelial cells in both cyclic endometria and endometrial carcinomas. Vasohibin was highly expressed in the normal functional endmetrium of the secretory phase, especially in the spiral artery, and was highly expressed in all grades of endometrioid adenocarcinomas. The stromal endothelial cells in G3 expressed vasohibin and VEGFR-2 more frequently than these in G1. In endometrioid adenocarcinomas, there was a significant correlation between the expression percentage of vasohibin and that of VEGFR-2 (P < 0.0001, r(2) = 0.591). This is the first study to elucidate the correlation between expression of vasohibin in the stromal endothelial cells and that of VEGFR-2 in human carcinomas.

Cap43/NDRG1/Drg-1 is a molecular target for angiogenesis and a prognostic indicator in cervical adenocarcinoma

Cap43 is a nickel- and calcium-inducible gene that plays important roles in the primary growth of malignant tumors, as well as in invasion and metastasis, most likely through its ability to induce cellular differentiation. This study investigated associations of Cap43 expression with angiogenesis and other clinicopathological factors in cervical adenocarcinoma. The clinical records of 100 women who underwent surgery for cervical adenocarcinoma were reviewed retrospectively. Microvessel density and the expression of Cap43 and VEGF in the surgical specimens were evaluated immunohistochemically. The Cap43 expression level was significantly associated with angiogenesis, tumor diameter, stromal invasion, lymphovascular space invasion, lymph node metastasis, and histopathological differentiation. Kaplan-Meier analysis showed a significant association between the Cap43 expression level and survival: high Cap43 expression was related to poor survival. Our results suggest that increased expression of Cap43 is associated with angiogenesis and may be a poor prognostic indicator in women with cervical adenocarcinoma.

Expression of vascular endothelial growth factor and assessment of microvascular density with CD 34 and endoglin in proliferative endometrium, endometrial hyperplasia, and endometrial carcinoma

The aim of this study was to compare vascular endothelial growth factor (VEGF), CD 34, and endoglin expressions as markers of angiogenesis in proliferative endometrium (PE), endometrial hyperplasia (EH), and endometrial carcinoma (EC) and to find the possible impact of angiogenesis on malign transformation. Formalin-fixed, paraffin-embedded tissues from 12 patients with PE, 23 patients with simple EH and complex EH with atypia, and 31 patients with EC were included. A semiquantitative scoring system was used to assess the intensity and degree of staining of VEGF. Microvessel density (MVD) was assessed with endoglin and anti-CD 34 in most vascular areas. VEGF expression was significantly higher in EC and EH than PE, but there was no difference between EC and EH. According to CD 34 staining, there were no differences in MVD between groups. However, mean MVD counts assessed by endoglin were significantly higher in EC than PE and EH. Although VEGF expression in EC was significantly higher, it did not correlate with other measures of angiogenesis. MVD using endoglin seemed to reflect neoplastic angiogenesis better than CD 34

A phase II trial of thalidomide in patients with refractory leiomyosarcoma of the uterus and correlation with biomarkers of angiogenesis: A gynecologic oncology group study

OBJECTIVES

To evaluate the efficacy and adverse events (AEs) of thalidomide in previously treated, measurable, persistent or recurrent leiomyosarcoma (LMS) of the uterus, and to explore associations between angiogenic markers and treatment or clinical outcome.

METHODS

Eligible, consenting patients were treated until disease progression or toxicity intervened with daily starting dose of 200 mg thalidomide/day that was increased by 200 mg every 2 weeks to a target dose of 1000 mg/day. End-points included progression-free survival (PFS)>or=6 months, toxicity, response, PFS and survival. Vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and soluble endothelial protein C receptor (sEPCR) were evaluated in pre- and post-treatment serum and plasma.

RESULTS

Of 30 enrolled patients, one was ineligible (wrong histology). Median age was 56 years. Among 29 eligible patients, seven reached the target dose and only two received more than 4 cycles. Two patients (7%) experienced PFS>or=6 months. There were no objective responses, seven (24%) had stable disease, 19 (66%) progressed and 3 (10%) were not evaluable for response. Median PFS was 1.9 months and median overall survival was 8.3 months. Grade 4 AEs were not observed. The most common grade 3 AEs were neurologic (6), pulmonary (4) and constitutional (3). Treatment with thalidomide was associated with a significant decrease in plasma bFGF (p=0.008) and serum sEPCR (p=0.006), but not in plasma VEGF. Plasma VEGF was associated with increased risk of progression (hazard ratio [HR]=3.5; 95% confidence interval (CI)=1.5-7.8; p=0.003) and death (HR=4.7; 95% CI=1.6-13.8; p=0.005) after adjusting for GOG performance status.

CONCLUSIONS

Thalidomide was not active in patients with uterine LMS and did not alter VEGF concentration. The association between pretreatment VEGF and prognosis in this population supports further evaluation of anti-angiogenic therapies in uterine LMS.

Vascular endothelial growth factor receptor-2: structure, function, intracellular signalling and therapeutic inhibition

Vascular endothelial growth factors (VEGFs) regulate vascular development, angiogenesis and lymphangiogenesis by binding to a number of receptors. VEGFR-1 is required for the recruitment of haematopoietic stem cells and the migration of monocytes and macrophages, VEGFR-2 regulates vascular endothelial function and VEGFR-3 regulates lymphatic endothelial cell function. Over the last decade, considerable progress has been made in delineating the VEGFR-2 specific intracellular signalling cascades leading to proliferation, migration, survival and increased permeability, each of which contributes to the angiogenic response. Furthermore, therapeutic inhibition of VEGFR-2 action is now having an impact in the clinic for the treatment of a number of diseases.

A phase II trial of thalidomide in patients with refractory endometrial cancer and correlation with angiogenesis biomarkers: a Gynecologic Oncology Group study

OBJECTIVES

A phase II trial was conducted to evaluate the anti-tumor activity and adverse effects of thalidomide in persistent or recurrent endometrial cancer refractory to cytotoxic chemotherapy and to correlate angiogenesis biomarker expression with clinical outcome.

METHODS

Consenting patients were treated until progression or intolerable toxicity with an oral starting dose of 200 mg thalidomide/day that was to increase by 200 mg every 2 weeks to a target dose of 1000 mg/day. Vascular endothelial growth factor (VEGF), basic fibroblastic growth factor (bFGF), and soluble endothelial protein C receptor (sEPCR) were analyzed by ELISA in pre and post-treatment specimens.

RESULTS

Twenty-four of twenty-seven patients enrolled in the study were eligible, of whom 2 reached the target dose, 8 progressed before achieving the target dose, and 14 refused or had toxicity that prohibited escalation. Two patients (8.3%) remained progression-free>or=6 months. There were 3 (12.5%) with partial responses, 2 (8.3%) with stable disease, 15 (62.5%) with increasing disease, and 4 (16.7%) who were inevaluable for response. Median progression-free survival and overall survival were 1.7 months and 6.3 months, respectively. No grade 4 toxicities were observed. Common grade 3 toxicities included hematologic (n=3), cardiovascular (n=3), constitutional (n=3), and neurologic (n=4). Thalidomide did not decrease VEGF or bFGF levels but reduced sEPCR levels in serum. Elevated plasma vascular endothelial growth factor levels were associated with increased risk of progression and death.

CONCLUSIONS

Thalidomide demonstrated limited ability to delay progression (as measured by PFS at 6 months), produce objective responses, or reduce angiogenic marker levels in chemotherapy refractory endometrial cancer. VEGF level appears to be prognostically significant in such patients, independent of thalidomide treatment.

The ratio of membrane-bound form Flt-1 mRNA to VEGF mRNA correlates with tumor angiogenesis and prognosis in non-small cell lung cancer

Fms-like tyrosine kinase 1 (Flt-1), a receptor for vascular endothelial growth factor (VEGF), have two isoforms: membrane-bound form (mFlt-1) and soluble form. In the present study, we quantitatively evaluated expression level of mFlt-1 mRNA and VEGF mRNA in non-small cell lung cancer, and demonstrated the clinical significance of the ratio of mFlt-1 mRNA to VEGF mRNA (mFlt-1/VEGF). High mFlt-1/VEGF tumor showed a significantly lower microvessel density (P=0.004), and patients with high mFlt-1/VEGF tumor had a significantly favorable survival (P=0.037). Thus, the ratio of mFlt-1 mRNA to VEGF mRNA was inversely correlated with tumor angiogenesis, and was a significant prognostic factor.

The prognostic value of vascular endothelial growth factors (VEGFs)-A and -B and their receptor, VEGFR-1, in invasive breast carcinoma

OBJECTIVES

Vascular endothelial growth factors A and B (VEGF-A and VEGF-B) play a major role in angiogenesis and activate VEGF receptor 1 (VEGFR-1). However, the clinicopathologic and clinical value of VEGF-B and VEGFR-1 in invasive breast carcinoma remains unclear.

METHODS

We immunohistochemically examined the expression pattern of VEGF-A, VEGF-B and VEGFR-1 in 177 invasive breast carcinomas in relation to clinicopathological parameters, p53, c-erbB2 proteins expression and patients' survival.

RESULTS

VEGF-A, VEGF-B and VEGFR-1 were immunodetected predominantly in the cytoplasm of the malignant cells. None of the studied markers correlated with any of the clinicopathological parameters, other than stromal VEGFR-1 which inversely correlated with PR (p=0.021). Cancerous VEGF-A and stromal VEGFR-1 were positively related to p53 (p=0.016 and p=0.033, respectively). Cancerous VEGF-B was positively associated with c-erbB-2 (p=0.045) and was found to exert an unfavorable impact on both disease-free and the overall survival of the node-positive patients (p=0.05 and p=0.029, respectively). Cancerous VEGFR-1 was recognized as being an independent poor prognostic indicator (p=0.037).

CONCLUSION

These findings suggest that, while VEGF-B seems to be useful as a prognostic indicator only in node-positive patients, VEGFR-1 may be an independent poor prognosticator in patients with invasive breast carcinoma.

Molecular alterations in the pathogenesis of endometrial adenocarcinoma. Therapeutic implications

Molecular genetic evidence indicates that endometrial carcinoma likely develops as the result of a multistep process of oncogene activation and tumor suppressor gene inactivation. These molecular alterations appear to be specific for Type I (endometrioid) and Type II (non endometrioid) cancers. Type I cancers are characterized by mutation of PTEN, KRAS2, defects in DNA mismatch repair, as evidenced by the microsatellite instability phenotype, and a near diploid karyotype. Type II cancers often contain mutations of TP53 and Her-2/neu and are usually nondiploid. The clinical value of many of these molecular markers is now being tested and it may help to refine diagnosis and establish an accurate prognosis. Furthermore, some of these tumor biomarkers constitute the targets for emerging therapies. Transtuzumab against Her-2/neu and bevacizumab against VEGF overexpressing carcinomas are among the promising novel treatments. Additional translational research is needed to identify molecular and genetic alterations with potential for therapeutic interventions.

The vascular-targeting fusion toxin VEGF121/rGel inhibits the growth of orthotopic human bladder carcinoma tumors

Vascular endothelial growth factor (VEGF) and its receptors (FLT-1 and KDR) are overexpressed by human bladder cancer cells and tumor endothelial cells, respectively. Strategies that target VEGF receptors hold promise as antiangiogenic therapeutic approaches to bladder cancer. A fusion protein of VEGF121 and the plant toxin gelonin (rGel) was constructed, expressed in bacteria, and purified to homogeneity. Cytotoxicity experiments of VEGF121/rGel on the highly metastatic 253J B-V human bladder cancer cell line demonstrated that the VEGF121/rGel does not specifically target these cells, whereas Western blot analysis showed no detectable expression of KDR. Treatment with VEGF121/rGel against orthotopically implanted 253J B-V xenografts in nude mice resulted in a significant suppression of bladder tumor growth (approximately 60% inhibition; P < .05) compared to controls. Immunohistochemistry studies of orthotopic 253J B-V tumors demonstrated that KDR is highly overexpressed in tumor vasculature. Immunofluorescence staining with antibodies to CD-31 (blood vessel endothelium) and rGel demonstrated a dramatic colocalization of the construct on tumor neovasculature. Treated tumors also displayed an increase in terminal deoxynucleotidyl transferase-mediated dUTP-biotin end labeling staining compared to controls. Thus, VEGF121/rGel inhibits the growth of human bladder cancer by cytotoxic effects directed against the tumor vascular supply and has significant potential as a novel antiangiogenic therapeutic against human bladder cancer.

Update on angiogenesis inhibitors

PURPOSE OF REVIEW

A number of therapeutic agents have been developed which have anti-angiogenic potential. Here we present the most recent data from clinical trials with some of the promising inhibitors of angiogenesis.

RECENT FINDINGS

Agents that target the vascular endothelial growth factor signaling pathway are the furthest along in clinical development. The last year has brought US Food and Drug Administration approval of bevacizumab (Avastin), a recombinant humanized anti-vascular endothelial growth factor monoclonal antibody. Bevacizumab has demonstrated a survival advantage in combination with chemotherapy for patients with metastatic colorectal cancer. Other agents with early promising results include PTK787/ZK 222584 (Vatalanib), ZD6474, and BAY 43-9006 (Sorafenib).

SUMMARY

Angiogenesis inhibitors show promise, but evaluation for optimal efficacy has been a problem, given that the mechanisms of action of these agents differ from conventional cytotoxic agents and surrogate markers for inhibition of angiogenesis are not available.

Vascular endothelial growth factor mRNA levels quantified by reverse transcription-polymerase chain reaction in microdissected breast carcinoma tissues are correlated with histological type and grade of both invasive and intraductal components

In breast cancer, vascular endothelial growth factor (VEGF) is a prognostic factor, but the relationship of VEGF mRNA levels with various parameters or tumor progression is unclear. VEGF mRNA levels were measured in 48 cases of invasive ductal carcinoma by using laser capture microdissection and quantitative reverse transcription-polymerase chain reaction (RT-PCR). The mean VEGF mRNA levels were compared among different histological types and grades in 41 and 29 samples of invasive and intraductal components, respectively. VEGF mRNA levels were always higher in cancerous cells than in non-cancerous cells, but mean VEGF mRNA levels were not significantly different between invasive component (3.24 +/- 3.18-fold the value of non-cancerous tissue) and intraductal component (4.14 +/- 4.43-fold). They were higher in papillotubular type than in other types, and higher in grade 2 carcinomas than in grade 3 carcinomas of invasive component, and higher in comedo type than in other types of intraductal component. Mean VEGF mRNA levels were higher in the VEGF-immunopositive group than in the VEGF-immunonegative group. There was no correlation between VEGF mRNA levels and tumor size, nodal status, or hormone receptor status. VEGF expression may play an important role in the development of both invasive and intraductal carcinoma components, especially those carcinoma components of less aggressive histological features.

VEGF and its receptors (flt-1 and KDR/flk-1) as prognostic indicators in endometrial carcinoma

Vascular endothelial growth factor (VEGF) is associated with increased angiogenesis and aggressive tumour growth. We investigated the expression and clinical significance of VEGF and its receptors, flt-1 and KDR/flk-1, in patients with uterine endometrial carcinoma. The series consisted of 115 endometrioid endometrial adenocarcinoma patients with FIGO stage I-IV. Additionally, samples from 3 patients with adenoacanthoma and 12 patients with poor prognostic variants of endometrial carcinoma were examined. Immunohistochemical assessment was classified as negative or positive based on staining intensity. The median follow-up time of patients with endometrioid endometrial adenocarcinoma was 87 months. In endometrioid endometrial carcinomas, the positive immunostaining rate was 39% for VEGF, 65% for flt-1 and 68% for KDR/flk-1. There was a significant correlation between VEGF and both its receptors. Furthermore, this receptor expression was correlated between the two types of receptors. VEGF-, flt-1- and KDR/flk-1-positive immunostainings were not related to poor prognosis. We conclude that VEGF, flt-1 and KDR/flk-1 expressions are not useful prognostic markers for overall survival in patients with endometrioid endometrial carcinoma.

The expression and cellular localization of phosphorylated VEGFR2 in lymphoma and non-neoplastic lymphadenopathy: an immunohistochemical study

AIMS

To study the expression of phosphorylated vascular endothelial growth factor receptor 2 (VEGFR2), a membrane-bound tyrosine kinase receptor to vascular endothelial growth factor, in lymphoma and non-neoplastic lymphadenopathy.

METHODS AND RESULTS

Archival cases (89 cases of lymphoma and 17 cases of non-neoplastic lymphadenopathy) were studied immunohistochemically with three monoclonal antibodies to the different autophosphorylation sites in the cytoplasmic tail of the receptor. There was increased expression of this receptor in lymphoma and particularly in all cases of peripheral T-cell lymphoma. In this category, there was nuclear re-location of this receptor.

CONCLUSIONS

This very interesting finding raises the possibility that VEGFR2 may be involved in the transcriptional regulation of this disease. Small molecule inhibitors to this receptor may therefore be a useful adjunct in the therapy of this disease.

Prognostic importance of vascular endothelial growth factor and its receptors in the uterine sarcoma

Vascular endothelial growth factor (VEGF) and its receptors play an important role in tumor progression; however, there is no report regarding this factor in uterine sarcoma. Thirty-nine patients with uterine sarcoma, 14 carcinosarcomas, 4 endometrial stromal sarcomas, and 21 leiomyosarcomas, were studied. By immunohistochemical staining, VEGF was not detected in normal uterine smooth muscle, but VEGF receptor-1 (flt-1) and VEGF receptor-2 (flk-1) were observed in 14 and 4 of 14 normal smooth muscles, respectively. Of 39 sarcomas, 25 expressed VEGF, and 38 and 34 sarcomas expressed flt-1 and flk-1 at various intensities, respectively. The staining intensity of VEGF, flt-1, and flk-1 was significantly higher in sarcoma than in normal uterine smooth muscle, but that of phospho-flt-1 (p-flt-1) was significantly lower in sarcoma than in normal uterine smooth muscle. When sarcomas were divided into two groups according to staining intensity, a significant difference in survival curves was observed in only p-flt-1 of leiomyosarcoma (P= 0.008), and in all sarcomas, a lower survival curve was also observed in the high staining intensity group than in the low staining intensity group, although there was no significant difference (P= 0.102). In conclusion, VEGF and its receptors are suggested to be involved in progression of uterine sarcoma, but only the p-flt-1 level significantly affected the survival of leiomyosarcoma patients.

Intratumoral CD8+ T lymphocytes as a prognostic factor of survival in endometrial carcinoma

PURPOSE

CTLs are a prominent immune component infiltrating many solid tumors. These cells are considered to be a manifestation of host-immune response to the tumor; however, their prognostic significance remains a subject of considerable debate. The objective of this study was to evaluate the distribution pattern and prognostic value of CD8(+) T cells in endometrial carcinoma.

EXPERIMENTAL DESIGN

We studied 90 cases of endometrial carcinoma, including 75 endometrioid and 15 papillary serous carcinomas. Immunohistochemical staining for CD8 and granzyme B was performed on paraffin-embedded sections. The number of immunohistochemically staining CD8(+) T cells was enumerated in the following four regions: lymphocytes infiltrating the tumor epithelium at the invasive border, within the underlying tumor stroma, within the superficial tumor epithelium, and in the perivascular areas of the myometrium.

RESULTS

Patients with >10 CD8(+) T lymphocytes/high-power field within the tumor epithelium at the invasive border displayed improved overall survival compared with patients with fewer intraepithelial CD8(+) T lymphocytes (87 and 50%, respectively; P = 0.027). Multivariate analysis revealed that stage, vascular invasion, grade, and the number of intraepithelial CD8(+) T lymphocytes at the invasive border were the only independent predictors of survival (P < 0.0001, P = 0.001, P = 0.011, and P = 0.025, respectively). Granzyme B(+) cytoplasmatic granules were detected in a high proportion of CTLs, confirming their activated cytotoxic phenotype.

CONCLUSIONS

Our study demonstrates for the first time that increased numbers of CTLs at the invasive border may be a reliable independent prognostic factor of survival in patients with endometrial carcinoma.

Inability of immunohistochemistry to predict clinical outcomes of endometrial cancer patients

INTRODUCTION

Despite optimal surgery, some patients with early endometrial carcinoma develop recurrence and die of disease. A number of immunohistochemical (IHC)-identified cell products (markers) have been proposed as predictors of recurrence. This study characterizes a large series of endometrial carcinomas with previously described markers as well as markers that have not been investigated in endometrial carcinoma.

PATIENTS AND METHODS

Women who had undergone surgery for endometrial carcinoma were identified and specimens accessed. Tissue blocks were evaluated for ten IHC markers. Results were correlated with last known clinical status.

RESULTS

Mean follow-up was 43 months; complete data were available on 117 patients. Two women died of other causes; of the remaining 115, eight died of disease and six were alive with recurrence at last follow-up (12%). Vascular endothelial growth factor staining independently predicted recurrence and death. However, in multivariate analyses, only FIGO stage predicted outcome.

DISCUSSION

Our goal was to identify markers to predict which women with endometrial carcinoma were likely to have disease recurrence. We evaluated cell-cycle regulatory proteins, growth factors, hormone receptors, and angiogenic factors, but did not identify any marker that independently predicted outcome in multivariate analysis. This may reflect the few negative outcomes in our population.

Expression of the VEGF and angiopoietin genes in endometrial atypical hyperplasia and endometrial cancer

Angiogenesis is critical for the growth and metastasis of endometrial cancer and is therefore an important therapeutic target. Vascular endothelial growth factor-A (VEGF-A) is a key molecule in angiogenesis, but the identification of related molecules and the angiopoietins suggests a more complex picture. We investigated the presence of transcripts for VEGF-A, VEGF-B, VEGF-C, VEGF-D, Angiopoietin-1 and Angiopoietin-2 in benign endometrium, atypical complex hyperplasia (ACH) and endometrioid endometrial carcinoma using in situ hybridisation. We confirmed the presence of VEGF-A mRNA in the epithelial cells of cancers examined (13 out of 13), but not in benign endometrium or ACH. We also demonstrate, using quantitative polymerase chain reaction, that levels of VEGF-B mRNA are significantly lower in endometrial cancer than benign endometrium. We conclude that loss of VEGF-B may contribute to the development of endometrial carcinoma by modulating availability of receptors for VEGF-A.

Endoglin (CD105) expression in endometrial carcinoma

Tumor angiogenesis plays an important role in tumor growth and metastasis. We evaluated endoglin (CD105) as an endothelial marker of angiogenesis in endometrial carcinoma (EC) and its prognostic significance. Fifty-five cases of EC, 10 cases of complex endometrial hyperplasia with atypia (CHA), and 10 cases of simple hyperplasia (SH) were immunohistochemically stained for endoglin, CD31, and vascular endothelial growth factor (VEGF). Positively stained microvessels (MV) were counted in densely vascular foci (hot spots) in a 400x field in each specimen. For VEGF, intensity of staining was scored on three-tiered scale. Results were correlated with other prognostic parameters using appropriate statistics. Endoglin staining demonstrated significantly more MV than did CD31 (mean 30.8 +/- 10.95 vs. 13.38 +/- 7.53, p < 0.001). There was a positive correlation of both endoglin and CD31 MV counts with tumor differentiation (p < 0.05) and the depth of invasion (p < 0.01). However, only endoglin counts correlated significantly with the presence of angiolymphatic invasion (p < 0.01), lymph nodes metastases (p < 0.01), and tumor stage (p < 0.001). VEGF expression in EC had a significant correlation with angiolymphatic invasion (p < 0.01) and lymph node status (p < 0.05) but not with other prognostic parameters. Endoglin and VEGF showed significant differences between CHA and SH (p < 0.001). Our study showed that endoglin, by staining the proliferating MV in EC, is a more specific and sensitive marker for tumor angiogenesis than is the commonly used pan-endothelial marker, CD31. Endoglin staining also had prognostic significance, with positive correlation with angiolymphatic invasion, lymph node metastases, and tumor stage.

Malignant mesothelioma growth inhibition by agents that target the VEGF and VEGF-C autocrine loops

Malignant mesothelioma (MM) is a locally aggressive tumor that originates from the mesothelial cells of the pleural and sometimes peritoneal surface. Conventional treatments for MM, consisting of chemotherapy or surgery give little survival benefit to patients, who generally die within 1 year of diagnosis. Hence, there is an urgent need for the development of alternative therapies. Vascular endothelial growth factor (VEGF) is an autocrine growth factor for MM. The closely related molecule, VEGF-C, is also implicated in malignant mesothelioma growth. VEGF-C and its cognate receptor VEGFR-3 are co-expressed in mesothelioma cell lines. A functional VEGF-C autocrine growth loop was demonstrated in mesothelioma cells by targeting VEGF-C expression and binding to VEGFR-3. The ability of novel agents that reduce the levels of VEGF and VEGF-C to inhibit mesothelioma cell growth in vitro was assessed. Antisense oligonucleotide (ODN) complementary to VEGF that inhibited VEGF and VEGF-C expression simultaneously specifically inhibited mesothelioma cell growth. Similarly, antibodies to VEGF receptor (VEGFR-2) and VEGF-C receptor (VEGFR-3) were synergistic in inhibiting mesothelioma cell growth. In addition, a diphtheria toxin-VEGF fusion protein (DT-VEGF), which is toxic to cells that express VEGF receptors was very effective in inhibiting mesothelioma cell growth in vitro. These results indicate that targeting VEGF and VEGF-C simultaneously may be an effective therapeutic approach for malignant mesothelioma.

Prognostic value of vascular endothelial growth factor in Stage IB carcinoma of the uterine cervix

PURPOSE

To clarify the role of vascular endothelial growth factor (VEGF) expression as an independent prognostic factor in Stage IB cervical cancer.

METHODS AND MATERIALS

A total of 117 patients with Stage IB cervical cancer who had undergone radical hysterectomy and pelvic lymph node dissection with complete histopathologic examination were included. Eighty-eight (75.2%) patients received postoperative radiotherapy and/or chemotherapy. VEGF expression was examined using immunohistochemistry.

RESULTS

Of 117 patients, 35 (29.9%) showed high-intensity VEGF expression and 69 (59%) had a high score for area of VEGF expression. Strong correlations were found between high VEGF intensity and both deep stromal invasion (p = 0.01) and positive pelvic lymph nodes (p = 0.03). The area of VEGF expression was significantly associated with tumor size (p = 0.02). In a multivariate analysis, high VEGF intensity (p = 0.009) and tumor size (p = 0.01) were significant prognostic factors for overall survival and disease-free survival (p = 0.001 and p = 0.003, respectively). However, the area of VEGF expression was not a prognostic factor for overall survival or disease-free survival.

CONCLUSION

Our findings on the correlation between VEGF expression and prognosis were conflicting. Functional and quantitative tools to assess tumor angiogenesis in addition to the expression of VEGF need to be developed and would be helpful to support the finding that tumor angiogenesis correlates significantly with prognosis in early-stage cervical cancer.

Angiogenic co-operation of VEGF and stromal cell TP in endometrial carcinomas

Vascular endothelial growth factor (VEGF) and thymidine phosphorylase (TP) are important angiogenic enzymes, inducing new blood vessel formation in many human malignancies. In this study, the immunohistochemical expression of the two molecules was analysed in a series of 121 endometrial carcinomas. VEGF was expressed exclusively in cancer cells, while TP expression was shown in cancer cells (TPcc) and in stromal cells (TPsc) of both fibroblastic and myometrial origin. In all cases, enzymatic detection was particularly evident at the invading tumour front. At this site, TPsc, but not VEGF, expression was associated with non-endometrioid-type carcinomas, high tumour grade, deep myometrial invasion, and advanced stage. VEGF, but not TP, expression was related to increased angiogenesis (p=0.01). Double stratification of the two factors, however, marked VEGF/TPsc co-expression as the most potent angiogenic phenotype (p=0.008), suggesting a synergistic function. Survival analysis revealed that VEGF and TPsc, whether expressed alone or in combination, define poor prognosis. In multivariate analysis, however, stage of disease (p<0.0001, t-ratio 4.4) and VEGF expression (p=0.01, t-ratio 2.4) were the most important prognostic variables. Furthermore, VEGF expression emerged as the only independent prognostic variable in stage I endometrial carcinomas (p=0.04, t-ratio 1.9). This was not shown for TP, probably because of its close association with histopathological parameters. In conclusion, VEGF is a major angiogenic factor in endometrial carcinomas and an independent prognostic factor in stage I endometrial disease. TP is not an effective contributor to the angiogenic process, but is associated with aggressive histological features. The two factors, when co-expressed, play a co-operative role in the induction of angiogenesis.

The angiogenic "vascular endothelial growth factor/flk-1(KDR) receptor" pathway in patients with endometrial carcinoma: prognostic and therapeutic implications

BACKGROUND

Vascular endothelial growth factor (VEGF) is an important endothelial cell mitogen associated with increased angiogenesis and aggressive tumor behavior. Its stimulating effect on endothelial cells basically is dependent on the presence of specific VEGF receptors, such as the flk-1(KDR) receptor. This study investigates the roles of VEGF and of a functionally intact angiogenic pathway, "VEGF/flk-1(KDR)," in patients with endometrial carcinoma and their significance in prognosis and therapy.

METHODS

A series of 121 endometrial carcinomas were studied. The expression of VEGF by endometrial tumor cells was assessed using the monoclonal antibody (MoAb) VG1. VEGF/KDR complexes on tumor endothelium or activated microvessel density (aMVD) were identified using the MoAb 11B5. In addition, the standard microvessel density (sMVD) was assessed with anti-CD31. In all tumors, the alkaline phosphatase/antialkaline phosphatase technique was employed. A Fisher exact test or an unpaired, two-tailed t test was used for testing correlations between categoric tumor variables, whereas a log-rank test was used to determine statistical differences between life tables. A Cox proportional hazards model was used to assess the effect of tumor variables on overall survival.

RESULTS

Cytoplasmic VEGF expression in > 50% of tumor cells was associated significantly with aMVD (P < 0.0001) and with sMVD (P < 0.003). In univariate survival analysis, VEGF (P = 0.0002), aMVD (P = 0.001), and sMVD (P = 0.0009) were significant prognostic variables. Equally important were the histologic parameters tumor type (P = 0.03), tumor grade (P = 0.003), and disease stage (P < 0.0001). In multivariate analysis, disease stage was the most important independent prognostic factor (P < 0.0001), followed by VEGF/KDR (P < 0.01), and VEGF (P < 0.04). Furthermore, VEGF and VEGF/KDR were the only independent prognostic variables for patients with Stage I endometrioid adenocarcinoma.

CONCLUSIONS

sMVD and the angiogenic factor VEGF are important indicators of a poor prognosis in patients with endometrial carcinoma. VEGF/KDR complexes define a subgroup of patients with endometrial carcinoma with an even worse prognosis.

Prognostic significance of the expression of vascular endothelial growth factor (VEGF) and VEGF-C in gastric carcinoma

BACKGROUND AND OBJECTIVES

Angiogenic factors play a major role in tumor growth and metastasis. The purpose of this study was to clarify the prognostic significance of the expression of vascular endothelial growth factor (VEGF) and VEGF-C in gastric carcinoma.

METHODS

Formalin-fixed and paraffin embedded sections of tumor tissue were obtained from 76 patients who underwent curative gastrectomy for gastric carcinoma. Immunohistochemical staining for VEGF and VEGF-C was performed.

RESULTS

VEGF and VEGF-C were positively expressed in 39 and 45% of the patients, respectively. No correlation existed between VEGF and VEGF-C expressions. VEGF expression was significantly correlated with venous invasion. VEGF-C expression was significantly correlated with lymphatic and venous invasion. Patients with positive staining for VEGF showed a significantly lower survival rate than VEGF negative patients. After subdivision, according to the combination of VEGF and VEGF-C expression, VEGF-C expression had a significant unfavorable impact on prognosis among patients with negative staining for VEGF. The expression of VEGF and/or VEGF-C was independent prognostic determinant by the multivariate survival analysis.

CONCLUSIONS

The positive expression for VEGF and/or VEGF-C was an important prognostic determinant after curative gastrectomy for gastric carcinoma. VEGF-C may stimulate the tumor progression in the absence of VEGF.

Vascular endothelial growth factor (VEGF) is an autocrine growth factor for VEGF receptor-positive human tumors

Angiogenesis is required for the progression of tumors from a benign to a malignant phenotype and for metastasis. Malignant tumor cells secrete factors such as vascular endothelial growth factor (VEGF), which bind to their cognate receptors on endothelial cells to induce angiogenesis. Here it is shown that several tumor types express VEGF receptors (VEGFRs) and that inhibition of VEGF (VEGF antisense oligonucleotide AS-3) or VEGFRs (neutralizing antibodies) inhibited the proliferation of these cell lines in vitro. Furthermore, this effect was abrogated by exogenous VEGF. Thus, VEGF is an autocrine growth factor for tumor cell lines that express VEGFRs. A modified form of VEGF AS-3 (AS-3m), in which flanking 4 nucleotides were substituted with 2-O-methylnucleosides (mixed backbone oligonucleotides), retained specificity and was active when given orally or systemically in vitro and in murine tumor models. In VEGFR-2-expressing tumors, VEGF inhibition may have dual functions: direct inhibition of tumor cell growth and inhibition of angiogenesis.

Expression of vascular endothelial growth factors (VEGF-A/VEGF-1 and VEGF-C/VEGF-2) in postmenopausal uterine endometrial carcinoma

OBJECTIVE

We investigated the expression of two angiogenic vascular endothelial growth factors, VEGF-A/VEGF-1 and VEGF-C/VEGF-2, in 228 cases of uterine endometrial carcinomas from postmenopausal patients to evaluate the correlation with histopathologic features and clinical outcome.

METHODS

Immunohistochemistry was used to assess VEGF-A/VEGF-1 and VEGF-C/VEGF-2 expression in 228 primary surgically treated cases of postmenopausal endometrial carcinomas and the results were statistically analyzed in relation to vascular invasion, depth of invasion (myometrial vs serosal-parametrial invasion), lymphatic vessel invasion, lymph node metastasis, disease-free 5-year survival rate (DF5YR), and disease-free 10 year-survival rate (DF10YR).

RESULTS

The results of univariate analysis showed that VEGF-A/VEGF-1 and VEGF-C/VEGF-2 expression correlated with vascular invasion (P < 0.0001, P = 0.0006), depth of invasion (P = 0.0004, P = 0.043), lymphatic vessel invasion (P = 0.021, P < 0.0001), lymph node metastasis (P = 0.0017, P = 0.0008), DF5YR (P = 0.0081, P = 0.0002), and DF10YR (P = 0.0077, P = 0.0001). Multivariate analysis showed that lymph node metastasis (P = 0.0017, P = 0.0008), parametrial-serosal invasion (P < 0.0001, P < 0.0001), and VEGF-C/VEGF-2-positive status (P = 0.03, P = 0.01) were significant factors in DF5YR and DF10YR.

CONCLUSIONS

We conclude that VEGF-A/VEGF-1 and VEGF-C/VEGF-2 expression was predictive of these histopathologic features of endometrial carcinoma and clinical outcome.

Immunohistochemical analysis of gynecologic tumors

Ancillary techniques such as immunohistochemistry (IHC) enable the surgical pathologist to extract additional information from fixed, deparaffinized tissue specimens and to provide data critical to optimal clinical management of the patient. In this review of applications of IHC to the analysis of gynecologic malignancies, the usefulness of immunohistochemical analysis of neoplasms of the cervix, endometrium, and ovary is summarized. In the uterine cervix, dysplasia is associated with qualitative and quantitative alterations in the expression of the Ki-67 antigen expression, as well as an ability to detect human papillomavirus. Endometrial endometrioid adenocarcinomas display a highly characteristic immunophenotype, with coexpression of cytokeratin and vimentin and demonstration of foci of high molecular weight cytokeratin expression; in addition, IHC analysis of estrogen and progesterone receptor and p53 expression can provide important prognostic information about this tumor. Stromal tumors of the endometrium may display a partial smooth muscle immunophenotype, but novel markers such as CD10 provide new tools for the identification of these tumors. The immunophenotypes of the normal ovarian surface epithelium (OSE) and corresponding tumors display significant overlap with, but important distinctions from, mesothelium, and important new markers such as the Wilms tumor gene product can prove useful in the identification of carcinomas of the OSE. Important prognostic markers for carcinomas of the OSE include the HER-2/neu gene product and p53, alterations of which can both be assessed by IHC techniques. Finally, the recent availability of markers of ovarian stroma, including Melan-A and inhibin-alpha, has provided a means for the positive identification of ovarian stromal tumors, which can manifest protean histological appearances.