Functional and molecular analyses of 10q deletions in human gliomas.
Extensive genomic deletions involving chromosome 10 are the most common genetic alteration in glioblastoma multiforme (GBM). To localize and examine the potential roles of two chromosome arm 10q tumor suppressor regions, we used two independent strategies: mapping of allelic deletions, and functional analysis of phenotypic suppression after transfer of chromosome 10 fragments. By allelic deletion analysis, the region of 10q surrounding the MMAC/PTEN locus was shown to be frequently lost in GBMs but maintained in most low-grade astrocytic tumors. An additional region at 10q25 containing the DMBT1 locus was lost in all grades of gliomas examined. The potential biological significance of these two regions was further assessed by examining microcell hybrids that contained various fragments of 10q. Somatic cell hybrid clones that retained the MMAC/PTEN locus have a less transformed phenotype with clones exhibiting an inability to grow in soft agarose. However, presence or absence of DMBT1 did not correlate with any in vitro phenotype assessed in our model system. These results support a model of molecular progression in gliomas in which the frequent deletion of 10q25-26 is an early event and is followed by the deletion of the MMAC/PTEN during the progression to high-grade GBMs.
Steck
P A
PA
Department of Neuro-Oncology, The Brain Tumor Center, The University of Texas M.D. Anderson Cancer Center, Houston 77030, USA. steckpa@audumla.mdacc.tmc.edu
Lin
H
H
Langford
L A
LA
Jasser
S A
SA
Koul
D
D
Yung
W K
WK
Pershouse
M A
MA
D000373:Agglutinins; D015153:Blotting, Western; D001932:Brain Neoplasms / Q000235:genetics; D002135:Calcium-Binding Proteins; D002872:Chromosome Deletion; D002879:Chromosomes, Human, Pair 10 / Q000235:genetics*; D004273:DNA, Neoplasm / Q000032:analysis; D004268:DNA-Binding Proteins; D016147:Genes, Tumor Suppressor / Q000235:genetics; D005910:Glioma / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D019656:Loss of Heterozygosity / Q000235:genetics; D018895:Microsatellite Repeats / Q000235:genetics; D051059:PTEN Phosphohydrolase; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics; D011956:Receptors, Cell Surface / Q000032:analysis / Q000096:biosynthesis; D014407:Tumor Cells, Cultured; D025521:Tumor Suppressor Proteins
D000373:Agglutinins; D002135:Calcium-Binding Proteins; C108174:DMBT1 protein, human; D004273:DNA, Neoplasm; D004268:DNA-Binding Proteins; D011956:Receptors, Cell Surface; D025521:Tumor Suppressor Proteins; D010744:Phosphoric Monoester Hydrolases; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human