EVALUATION OF CUMULUS CELLS TRANSCRIPTOME IN PATIENTS UNDERGOING IN VITRO FERTILIZATION PROCEDURES TREATED WITH DIFFERENT CONTROLLED OVARIAN STIMULATION PROTOCOLS

Cumulus cells (CC) closely interact with the oocyte and share the same microenvironment. Therefore they may retain a footprint of the follicular conditions experienced by the oocyte. This observation has led various groups to focus their research on the analysis of CC gene expression, aimed at finding novel markers of oocyte competence and pregnancy outcome in natural and stimulated cycles. To evaluate CC expression profile modulation after different stimulation protocols, we analyzed CC transcriptome variations by microarray in patients undergoing different treatments for ovarian stimulation (hp-hMG and r-hLH plus r-hFSH), compared with a control group (r-hFSH). In this study, we collected samples derived from cumulus-oocyte complexes containing mature oocytes. We compared transcriptome genes differentially expressed in both treatment groups by using a hierarchic clustering analysis. Data analysis showed four genes clusters involved in oocyte development and maturation differentially expressed in both treatment groups compared with control. In conclusion, different stimulation regimens produce modifications in signaling and metabolic pathways of CCs that could potentially affect oocyte development.