Gene expression profiling of hypothalamic hamartomas: a search for genes associated with central precocious puberty.
BACKGROUND
Hypothalamic hamartomas (HHs) are congenital lesions composed of neurons and astroglia. Frequently, HHs cause central precocious puberty (CPP) and/or gelastic seizures. Because HHs might express genes similar to those required for the initiation of normal puberty, we used cDNA arrays to compare the gene expression profile of an HH associated with CPP with three HHs not accompanied by sexual precocity.


METHODS
Global changes in gene expression were detected using Affymetrix arrays. The results were confirmed by semiquantitative PCR, which also served to examine the expression of selected genes in the hypothalamus of female monkeys undergoing puberty.


RESULTS
All HHs were associated with seizures. Ten genes whose expression was increased in the HH with CPP were identified. They encode proteins involved in three key cellular processes: transcriptional regulation, cell-cell signaling, and cell adhesiveness. They include IA-1 and MEF2A, two transcription factors required for neuronal development; mGluR1 and VILIP-1, which encode proteins involved in neuronal communication, and TSG-6 that encodes a protein involved in cell adhesiveness. Of these, expression of mGluR1 also increases in the female monkey hypothalamus at puberty.


CONCLUSIONS
Increased expression of these genes in HHs may be relevant to the ability of some HHs to induce sexual precocity.
Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR 97006, USA.
Anne-Simone
AS
Parent
Valerie
V
Matagne
Manfred
M
Westphal
Sabine
S
Heger
Sergio
S
Ojeda
Heike
H
Jung
D000293:Adolescent; D000328:Adult; D000818:Animals; D015815:Cell Adhesion Molecules / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D004268:DNA-Binding Proteins / Q000235:genetics; D005260:Female; D020869:Gene Expression Profiling; D007987:Gonadotropin-Releasing Hormone / Q000235:genetics; D006222:Hamartoma / Q000150:complications / Q000235:genetics*; D006801:Humans; D007027:Hypothalamic Diseases / Q000150:complications / Q000235:genetics*; D059648:Kisspeptins; D008253:Macaca mulatta; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D011629:Puberty, Precocious / Q000209:etiology / Q000235:genetics*; D043562:Receptors, G-Protein-Coupled / Q000235:genetics; D000074502:Receptors, Kisspeptin-1; D018094:Receptors, Metabotropic Glutamate / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics; D012741:Sexual Maturation / Q000235:genetics; D016211:Transforming Growth Factor alpha / Q000235:genetics; D025521:Tumor Suppressor Proteins / Q000235:genetics
D015815:Cell Adhesion Molecules; D004268:DNA-Binding Proteins; C106628:KISS1 protein, human; C118688:KISS1R protein, human; D059648:Kisspeptins; D043562:Receptors, G-Protein-Coupled; D000074502:Receptors, Kisspeptin-1; D018094:Receptors, Metabotropic Glutamate; D012097:Repressor Proteins; C072273:TNFAIP6 protein, human; D016211:Transforming Growth Factor alpha; D025521:Tumor Suppressor Proteins; C104077:metabotropic glutamate receptor type 1; C087342:INSM1 protein, human; D007987:Gonadotropin-Releasing Hormone