Hsa-let-7b was also found to participate in follicular development in vitro and was found necessary for the normal development of the corpus luteum in mice. Another of the most abundant miRNAs, miR-320a, is expressed at much lower levels in the follicular fluid of PCOS patients and is also involved in the regulation of estradiol concentration. All of these reports suggest that the posttranscriptional regulation of gene expression by miRNAs plays an important role in ovarian cumulus cells. Moreover, in addition to determining the miRNA expression profile in CRCs and COCs, we were also interested in determining the differential miRNA profiles and their roles between the human CRCs and COCs. In total, 72 miRNAs were expressed differentially between human CRCs and COCs. Quantitative real-time PCR was used to validate these differentially expressed miRNAs, and it was shown that all tested miRNAs were differentially expressed in the two cell types. Thus, we conducted GO term annotation and KEGG pathway analysis for the identified miRNAs based on the prediction of miRNA targets. Notably, the metabolisms of several individual amino acids were enriched in the GO biological processes. Because oocytes are LY2835219 deficient in their ability to synthesise and transport several types of amino acids, the cumulus cells must provide oocytes with the amino acids or substrates for the metabolism of these amino acids. For instance in mice, oocytes cannot directly synthesise some amino acids, such as L-alanine, and thus require that cumulus cells synthesise and transfer these amino acids into oocytes. Oocytes are connected to surrounding cumulus cells via membrane specialisations, such as gap junctions, which act as physical channels for the transport of metabolites and nutrition between the oocyte and the cumulus cells.One source for the differences could have been the fact that most current assays measure a global chemotaxis index that depends on multiple aspects of neutrophil migration, including the fraction of the neutrophil population that are able to move, directionality or persistence of migration towards chemoattractant gradients.