Biopolymers and cell. 2007; 23 (4): 347 - 362

Characterization of genes, down-regulated in human glioma, potential tumor suppressor genes

V. V. Dmitrenko, O. I. Bojko, K. O. Shostak, N. Ya. Vitak, T. V. Bukreeva, V. D. Rozumenko, T. A. Malysheva, M. I. Shamayev, Yu. P. Zozulya, V. M. Kavsan

Comparison of gene expression profiles in human normal brain and glioblastoma using  SAGE database revealed 129 genes with 5-fold difference of expression level in glioblastoma (P≤0.05), 85 of them were down-regulated. The number of genes with 5-fold down-regulated expression is lower in the diffuse and anaplastic astrocytomas. Five-fold decrease in the expression in the diffuse astrocytoma and nearly the same expression levels in the anaplastic astrocytoma and glioblastoma were revealed for 9 genes only. For overwhelming majority of inactivated genes in the low-grade astrocytoma the expression decreased progressively in the subsequent stages of malignant progression of astrocytoma, expression levels of some genes were very low or undetectable in glioblastoma, the most aggressive brain tumor. The decreased expression of selected genes in glioblastoma was confirmed by Northern analysis and RT-PCR. Some genes, described in this work, may encode the tumor suppressors and their decreased expression may play an important role in initiation and progression of human glioma.

Keywords: glioma, astrocytoma, glioblastoma, down-regulated genes, potential tumor suppressors.