Quantitative Analysis of Gene Expressions of Vascular Endothelial Growth Factor-Related Factors and Their Receptors in Renal Cell Carcinoma

Quantitative Analysis of Gene Expressions of Vascular
Endothelial Growth Factor-Related Factors and
Their Receptors in Renal Cell Carcinoma

NORIHIKO TSUCHIYA, KAZUNARI SATO, TOSHIYA AKAO,¹ HIDEAKI KAKINUMA,
RYUSEI SASAKI, NAOTAKE SHIMODA, SHIGERU SATOH, TOMONORI HABUCHI,
OSAMU OGAWA¹ and TETSURO KATO

Departments of Urology, Akita University School of Medicine, Akita 010-8543, and
¹Kyoto University Graduate School of Medicine, 606-8397

Vascular endothelial growth factor (VEGF)-related factors are believed to regulate angiogenesis, an essential event in the growth of solid tumors. In this study, we investigated the expression of VEGF-related factor genes (VEGF, VEGF-B, and VEGF-C) and their receptor genes (VEGFR-1 and VEGFR-2) in renal cell carcinoma (RCC). There were significant differences in the expression level of VEGF, VEGFR-1 and VEGFR-2 between RCC and the corresponding normal renal tissue. The expression level of VEGF in the tumor tissue significantly correlated with those of VEGFR-1 and VEGFR-2. Expression levels VEGF-B and VEGF-C genes were not significantly different between RCC and normal renal tissue. A moderate to high protein expression for VEGF, VEGFR-1, and VEGFR-2 was observed in both the tumor cells and the endothelial cells, whereas the protein expression was low for VEGF-B and VEGF-C. The present results suggested that VEGF and its receptors VEGFR-1 and VEGFR-2 cooperates to play a crucial role in the angiogenesis of RCC, while VEGF-B and VEGFR-C may not. Furthermore, since VEGFR-1 and VEGFR-2 proteins were expressed in the tumor cells as well as in the endothelial cells, these receptors may also be responsible for the progression of RCC.

Keywords —— renal cell carcinoma; vascular endothelial growth factor; vascular endothelial growth factor receptor; gene expression; immunohistochemistry

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Tohoku J. Exp. Med., 2001, 195, 101-113

Address for reprints: Prof. Tetsuro Kato, Department of Urology, Akita University School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan.

e-mail: tkato@med.akita-u.ac.jp