Hypoxia-induced angiogenesis of cultured human salivary gland carcinoma cells enhances vascular endothelial growth factor production and basic fibroblast growth factor release

Ishibashi, H.; Shiratuchi, T.; Nakagawa, K.; Onimaru, M.; Sugiura, T.; Sueishi, K.; Shirasuna, K.

« Previous Next »Oral Oncology
Volume 37, Issue 1 , Pages 77-83, January 2001

Hypoxia-induced angiogenesis of cultured human salivary gland carcinoma cells enhances vascular endothelial growth factor production and basic fibroblast growth factor release

H. Ishibashi
- Second Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Graduate School of Medical Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-0054, Japan
- Corresponding author. Tel.: +81-92-642-6452; fax: 81-92-642-6392
T. Shiratuchi
- Second Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Graduate School of Medical Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-0054, Japan
K. Nakagawa
- Pathophysiological and Experimental Pathology, Department of Pathology, Graduate School of Medical Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-0054, Japan
M. Onimaru
- Second Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Graduate School of Medical Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-0054, Japan
- Pathophysiological and Experimental Pathology, Department of Pathology, Graduate School of Medical Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-0054, Japan
T. Sugiura
- Second Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Graduate School of Medical Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-0054, Japan
K. Sueishi
- Pathophysiological and Experimental Pathology, Department of Pathology, Graduate School of Medical Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-0054, Japan
K. Shirasuna
- Second Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Graduate School of Medical Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-0054, Japan

Received 9 May 2000; accepted 19 May 2000.

Abstract

The angiogenic activity of two human salivary gland tumor cell lines, ACCS from adenoid cystic carcinoma and IT-2 from mucoepidermoid carcinoma, was examined by stimulating tube formation by bovine capillary endothelial cells (BCE). ACCS and IT-2 were cultured in 20 or 3% oxygen, representing normoxic and hypoxic conditions, respectively, and conditioned medium (CM) was obtained from each culture. The BCE tubes stimulated by hypoxic CM were 1.59 (ACCS) and 1.42 (IT-2) times longer than those stimulated by normoxic CM. The tube-forming activity of CM was inhibited by preincubation with either anti-vascular endothelial growth factor (VEGF) IgG or anti-basic fibroblast growth factor (bFGF) IgG, suggesting that both VEGF and bFGF with angiogenic activity were present in the CM. This was confirmed by ELISA, which also demonstrated increased concentrations of both proteins in the hypoxic CM. Northern blot analysis showed an increased VEGF mRNA level in both carcinoma cells with hypoxia, while hypoxia did not affect the bFGF mRNA level in either cell line. The results suggest that both VEGF and bFGF are major angiogenesis factors in salivary gland tumors, and hypoxia-induced angiogenesis results from upregulation of VEGF and increased release of bFGF.

Keywords: Angiogenesis, Salivary gland carcinoma, Vascular endothelial growth factor, Basic fibroblast growth factor, Hypoxia