Expression of the multidrug-resistance P-glycoprotein (Pgp, MDR-1) by endothelial cells of the neovasculature in central nervous system tumors
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To elucidate the expression of theMDR1 gene products P-glycoprotein (Pgp) in endothelial cells on newly formed blood microvessels in brain tumors, 30 brain tumors were examined by immunohistochemistry using an anti-Pgp monoclonal antibody, JSB-1. Positive reactions for JSB-1 were detected in endothelial cells in newly formed microvessels in all 16 cases of glioma but not in the 4 meningiomas. Although endothelial cells in newly formed microvessels of all 10 metastatic carcinomas showed positive reactions, negative reactions were seen in those of the primary carcinomas. Compared with reactions of the endothelial cells of normal cerebral capillaries, weak reactions were found in the endothelial cells forming glomeruloid proliferation in newly formed microvessels in the eight glioblastomas and at the border of the surrounding cerebral tissue of the metastatic carcinomas. Since the endothelial cells showing glomeruloid proliferation also had a high proliferative cell nuclear antigen labeling index, the present findings demonstrate a negative relationship between positive reactions for Pgp and the proliferative activities of endothelial cells in cerebral capillaries.
Key wordsMDR-1 P-glycoprotein Blood-brain barrier Brain tumor Neovasculature VEGF
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- 4.Thiebault F, Tsuruo T, Hamada H, et al. (1989) Immunohistochemical localization in normal tissue of different epitopes in the multidrug transport protein P170: evidence for localization in brain capillaries and crossreactivity of one antibody with a muscle protein. J Histochem Cytochem 37:159–164Google Scholar
- 6.Sawada T, Nakamura M, Sakurai I (1998) An immunohistochemical study of neovascularization in human brain tumors. Acta Pathol Jpn 38:713–721Google Scholar
- 7.Takekawa Y, Sawada T, Sakurai I (1997) Neovascular basement membrane and its significance in the biological behavior of astrocytic tumors. Neuropathology 17:196–200Google Scholar
- 8.Matsumoto T, Tani E, Kaba K, et al. (1991) Expression of P-glycoprotein in human glioma cell lines and surgical glioma specimens. J Neurosurg 74:464–460Google Scholar
- 12.Shinkel HA, Roelofs MEM, Borst P (1991) Characterization of the human MDR3 P-glycoprotein and its recognition by P-glycoprotein-specific monoclonal antibodies. Cancer Res 51:2628–2635Google Scholar
- 17.Janigro D, Stanness KA, Nguyen T, et al. (1995) Possible role of glia in the induction of CNS-like properties in aortic endothelial cells: ATP-activated channels. In: Bellardinelli L, Pelleg A (eds) Adenosine and adenosine nucleotides. Nijhoff, Boston, pp 85–95Google Scholar