Lysyl oxidase interacts with AGE signalling to modulate collagen synthesis in polycystic ovarian tissue

Association between lysyl oxidase G473A polymorphism and ovarian cancer in the Han Chinese population

OBJECTIVE

Lysyl oxidase (LOX) is an extracellular enzyme critical for the cross-linking of collagens and elastin. A single-nucleotide polymorphism of LOX G473A is associated with various diseases. This retrospective study investigated the association between LOX G473A polymorphism and susceptibility to ovarian cancer in the Han Chinese population.

METHODS

The LOX variant G473A was detected by polymerase chain reaction-restriction fragment length polymorphism in patients with ovarian cancer and healthy control subjects.

RESULTS

The frequencies of the LOX 473AA genotype and the A allele were significantly higher in patients with ovarian cancer (n = 318) than in control subjects (n = 406) (odds ratio [OR] 2.30, 95% confidence interval [CI] 1.36, 3.87; OR 1.57, 95% CI 1.23, 2.00; respectively). The prevalence of the GA genotype, AA genotype and A allele were significantly higher in patients with more advanced stages of ovarian cancer compared with those with primary stage disease.

CONCLUSIONS

This study suggests that LOX G473A polymorphism is a new risk factor for ovarian cancer and that LOX protein might be a possible therapeutic target in ovarian cancer.

Emerging concepts about prenatal genesis, aberrant metabolism and treatment paradigms in polycystic ovary syndrome

The interactive nature of the 8th Annual Meeting of the Androgen Excess and PCOS Society Annual Meeting in Munich, Germany (AEPCOS 2010) and subsequent exchanges between speakers led to emerging concepts in PCOS regarding its genesis, metabolic dysfunction, and clinical treatment of inflammation, metabolic dysfunction, anovulation and hirsutism. Transition of care in congenital adrenal hyperplasia from pediatric to adult providers emerged as a potential model for care transition involving PCOS adolescents.

Endocrine disruptors and polycystic ovary syndrome (PCOS): elevated serum levels of bisphenol A in women with PCOS

CONTEXT

Bisphenol A (BPA) is a widespread industrial compound used in the synthesis of polycarbonate plastics. In experimental animals, neonatal exposure to BPA results in a polycystic ovary-like syndrome (PCOS) in adulthood. A bidirectional interaction between androgens and BPA levels has been disclosed.

OBJECTIVE

To determine BPA levels in PCOS women as well as the association between BPA and hormonal/metabolic parameters compared to a control group.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional study of 71 PCOS (National Institutes of Health criteria) and 100 normal women, age- and body mass index-matched, in a University hospital setting.

MAIN OUTCOME MEASURES

Anthropometric, hormonal, metabolic parameters and BPA blood levels were determined. Patients (PCOS) and controls (C) were further subdivided according to body mass index into lean and overweight subgroups, respectively.

RESULTS

BPA levels were significantly higher in the total PCOS group compared with the controls (1.05±0.56 vs. 0.72±0.37 ng/ml, P < 0.001). PCOS women, lean (PCOS-L) and overweight (PCOS-OW), had higher BPA levels compared to the corresponding control group lean (C-L) and overweight (C-OW): (PCOS-L = 1.13±0.63 vs. C-L = 0.70±0.36, P < 0.001) (PCOS-OW = 0.96 ± 0.46 vs. C-OW = 0.72 ± 0.39, P < 0.05). A significant association of testosterone (r = 0.192, P < 0.05) and androstenedione (r = 0.257, P < 0.05) with BPA was observed. Multiple regression analysis for BPA showed significant correlation with the existence of PCOS (r = 0.497, P < 0.05). BPA was also positively correlated with insulin resistance (Matsuda index) in the PCOS group (r = 0.273, P < 0.05).

CONCLUSIONS

Higher BPA levels in PCOS women compared to controls and a statistically significant positive association between androgens and BPA point to a potential role of this endocrine disruptor in PCOS pathophysiology.

Defective gonadotropin-dependent ovarian folliculogenesis and granulosa cell gene expression in inhibin-deficient mice

Inhibin-α knockout (Inha-/-) female mice develop sex cord-stromal ovarian cancer with complete penetrance and previous studies demonstrate that the pituitary gonadotropins (FSH and LH) are influential modifiers of granulosa cell tumor development and progression in inhibin-deficient females. Recent studies have demonstrated that Inha-/- ovarian follicles develop precociously to the early antral stage in prepubertal mice without any increase in serum FSH. These studies suggest that in the absence of inhibins, granulosa cells differentiate abnormally and thus at sexual maturity may undergo an abnormal response to gonadotropin signaling contributing to tumor development. To test this hypothesis, we stimulated immature wild-type and Inha-/- female mice with gonadotropin analogs prior to tumor formation and subsequently examined gonadotropin-induced ovarian follicle development as well as preovulatory and human chorionic gonadotropin-induced gene expression changes in granulosa cells. We find that at 3 wk of age, inhibin-deficient ovaries do not show further antral development or undergo cumulus expansion. In addition, there are widespread alterations in the transcriptome of gonadotropin-treated Inha-/- granulosa cells, with significant changes in genes involved in extracellular matrix and cell-cell communication. These data indicate the gonadotropins initiate an improper program of cell differentiation prior to tumor formation in the absence of inhibins.