Correlation of expressions of embryonic stem cell factor Nanog, Oct4, Sox2 with clinical characteristic of polycystic ovary syndrome

Objective To explore the relationship of expressions of embryonic stem cell factor Nanog, Oct4, Sox2 in granulosa cells with polycystic ovary syndrome (PCOS). Methods Totally 40 PCOS patients and 40 infertile cases due to tubal factors and/or male infertility who underwent in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) at the same period were recruited as experimental group and control group, respectivly. Real-time PCR was used to detect the expression levels of Nanog, Oct4, Sox2 and anti-Mullerian hormone (AMH) mRNA in granulosa cells. Logistic regression analysis was carried out on the pathogenesis of PCOS. Results Body mass index (BMI) [(26.44±3.46) kg/m2], lutenizing hormone (LH) [(7.56±0.98) IU/L], LH/follicluar stimulating hormone (FSH) (1.06±0.15) levels and the number of retrieved oocytes (28.7±3.9) were significantly increased in PCOS group compared with control group [(22.43±3.17) kg/m2, (4.26±0.34) IU/L, 0.57±0.04, 15.1±2.0] (P<0.05). However, the mRNA levels of Nanog (0.60±0.09) and Oct4 (0.85±0.14) in PCOS group were significantly lower than those in control group (1.65±0.17, 1.59±0.17) (P<0.05) and the mRNA level of AMH (1.28±0.11) was higher than that in control group (0.89±0.07) (P<0.05). Logistic regression analysis showed Nanog was a risk factor of PCOS, and the Nanog mRNA level was negatively associated with BMI, number of retrieved oocytes and AMH (r1=-0.415, P=0.023; r2=-0.415, P=0.022; r3=-0.373, P=0.043, respectively), and positively correlated with Oct4 (r=0.684, P<0.01). Western blotting results showed that the Nanog level decreased in PCOS group compared with control group. While, the AMH level increased. Conclusion The abnormal expression levels of Nanog and AMH in granulosa cells may be associated with the morbidity of PCOS and development and mature of oocyte. It will provide theoretical basis for treatment of PCOS. Key words: Embryonic stem cell factor; Polycystic ovary syndrome (PCOS); Nanog; Anti-Mullerian hormone (AMH)