Differential Gene Expression in Cultured Human Cumulus Cells From Polycystic Ovary Syndrome (PCOS)

Abstract

To compare gene expression in cultured human cumulus cells from PCOS and ovulatory patients Case Control study comparing gene expression of cultured cumulus cells from 6 anovulatory PCOS and 6 ovulatory patients using microarray technology. PCOS patients were defined according to the Rotterdam criteria. PCOS patients treated with Intracytoplasmic sperm injection (ICSI) due to male infertility, were included. Healthy controls undergoing in vitro fertilization (IVF) treatment for male factor infertility were matched according to body mass index (BMI). All patients underwent a long GnRH agonist ovarian stimulation protocol with rFSH. After oocyte retrieval cumulus cells were separated from the oocytes and cultured in DMEM/Ham’s F-12 for 48 hours. Following the incubation period, RNA was extracted (TRIreagent) and frozen at -700C. Expression profiling of each RNA sample was obtained using Affymetrix Human Genome U133 plus 2.0 arrays. Data were processed using the GeneSpring software. The study was approved by the local ethics committee and the national committee for human genetic experiments. 243 genes were differentially expressed. 70 of the genes were down regulated and 173 were upregulated. The genes can be grouped as follow: 22.5% of unknown protein or function, 14.3% miscellaneous, 12.7% cytoskeleton and extracellular matrix (CK/ECM), 7.8% DNA / RNA processing, 6.9% cell cycle, 6.5% protein biosynthesis and processing, 6.1% carbohydrate metabolism, 4.1% ubiquitin system, 3.7% lipid metabolism, 3.7% glycosylation, 3.7% electron transport, 3.3% cell development, 2.5% apoptosis, 2% protein and amino acid phosphorylation. 23 genes showed more than 4 fold differential expression level: 7 genes are of yet unknown function, while most of the others are involved with CK/ECM. Full genome expression pro .ling of cultured cumulus cells from PCOS vs.normal ovulating controls indicated that various genes show differential expression patterns.Of the known genes,the majority of the differentially expressed genes are involved in extracellular matrix/cytoskeleton and in cellular metabolism.