Vascular Endothelial Growth Factor Expression in Ovarian
Cancer: A Model for Targeted Use of Novel Therapies?
Timothy J. Duncan,
1
Ahmad Al-Attar,
1
Phil Rolland,
1
Ian V. Scott,
4
Suha Deen,
2
David T.Y. Liu,
3
Ian Spendlove,
1
and Lindy G. Durrant
1
Abstract Purpose: Angiogenesis has a vital role in tumor growth and metastasis, and vascular endothelial
growth factor (VEGF) represents a potent cytokine in this process. However, the influence of
VEGF in ovarian cancer remains controversial. Interest has focused on the use of antiangiogenic
drugs in ovarian cancer. This study aims to establish the pattern of expression and effect on
prognosis of VEGF in a large population of ovarian cancer patients and to potentially identify a
cohort in whom antiangiogenic therapy is appropriate.
Experimental Design: Using a tissue microarray of 339 primary ovarian cancers, the expression
of VEGF was assessed immunohistochemically. Coupled to a comprehensive database of
clinicopathologic variables, its effect on these factors and survival was studied.
Results: Tumors expressing high levels of VEGF had significantly poorer survival (P = 0.04).
Factors shown to predict prognosis independently of each other were age, International Federa-
tion of Gynecologists and Obstetricians stage, and the absence of macroscopic disease after
surgery. VEGF was independently predictive of prognosis on multivariate analysis (P = 0.02).
There was no correlation between VEGF and any clinicopathologic variable. High expression of
VEGF was seen in only 7% of the tumors, suggesting that the role of antiangiogenic drugs may
be limited to a small subset of patients.
Conclusion: High VEGF expression occurs in a small proportion of ovarian cancers, and this
independently predicts poor prognosis. The small percentage of tumors with high levels of
VEGF activity suggests that the role of bevacizumab may potentially be limited to a few patients;
these patients could be targeted by molecular profiling.
Ovarian cancer is the leading cause of death from gynecologic
malignancies. As symptoms are vague and nonspecific, these
tumors often present at an advanced stage. Developments in
chemotherapy and surgical techniques have had minimal effect
on patient survival over the last few decades (1).
Tumor stage and residual tumor mass, following primary
cytoreductive surgery, have been shown to most reliably predict
outcomes in patients with ovarian cancer (2) but offer no
information with regard to the potential sensitivity to
molecular ‘‘targeted’’ therapy. Investigation of novel prognostic
markers offers an insight into the mechanisms of tumor
development and suggests potential avenues for the develop-
ment of new therapeutic agents particularly through the use of
monoclonal antibody therapies.
Angiogenesis has been established as a vital component in
the mechanisms involved in tumor growth and metastasis
(3, 4). The angiogenic potential of tumors can be assessed by
microvessel density. Earlier studies illustrated the importance of
angiogenesis in tumor development, with microvessel density
directly correlating with a poor prognosis in ovarian (5) and
other tumors (6, 7).
Vascular endothelial growth factor (VEGF) is a multifunc-
tional cytokine that stimulates angiogenesis and increases
microvascular permeability through binding to specific recep-
tors expressed on vascular endothelial cells (8, 9). Although
VEGF is produced by several tumors and hypoxic tissues (10),
its receptors are expressed primarily by endothelial cells. It has
been shown to have a crucial role in neovascular formation in
tumors, providing nourishment for the highly metabolic tumor
cells as well as providing access to the host vasculature (11).
Studies have suggested a specific role for VEGF in various
phases of ovarian carcinogenesis, with effects on tumor
growth and neovascularization seen in animal models and
in humans (12, 13). Higher levels of VEGF are shown in
ovarian carcinomas when compared with normal ovaries
(14, 15).
Recent interest has focused on the use of antiangiogenic
drugs in an attempt to inhibit the protumor effects of VEGF
and other such cytokines. These studies have shown some
antitumor effects but have shown significant side effects.
Imaging, Diagnosis, Prognosis
Authors’Affiliations:
1
Academic and Clinical Department of Oncology, University
of Nottingham;
2
Division of Histopathology and
3
Department of Obstetrics and
Gynaecology, University Hospitals Nottingham, Nottingham, United Kingdom and
4
Department of Obstetrics and Gynaecology, Derby City General Hospital, Derby,
United Kingdom
Received 8/1/07; revised 1/27/08; accepted 2/7/08.
The costs of publication of this article were defrayed in part by the payment of page
charges. This article must therefore be hereby marked advertisement in accordance
with 18 U.S.C. Section 1734 solely to indicate this fact.
Requests for reprints: Lindy G. Durrant, Institute of Infections and Immunity,
University of Nottingham, Nottingham City Hospital NHS Trust, Hucknall Road,
Nottingham NG5 1PB, United Kingdom. Phone: 44-115-82-31862; Fax: 44-115-
82-31849/44-121-353-1482; E-mail: lindy.durrant@nottingham.ac.uk.
F 2008 American Association for Cancer Research.
doi:10.1158/1078-0432.CCR-07-1888
www.aacrjournals.org Clin Cancer Res 2008;14(10) May 15, 2008 3030
Research.
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