The objective of this study is to examine perinatal correlates of oestradiol (E2), oestriol (E3), progesterone and sex hormone-binding globulin (SHBG) among pregnant women in the USA and China. Three hundred and four Caucasian women in Boston and 335 Chinese women in Shanghai were studied. Levels of E2, E3, progesterone and SHBG were measured in maternal blood at weeks 16 and 27 of gestation, and correlated with maternal, gestational and perinatal characteristics. Height, weight and body mass index (BMI) before pregnancy is inversely associated with E2 and SHBG, whereas E3 is inversely associated with height and progesterone is inversely associated with weight and BMI. A previous live birth is associated with lower E2 and SHBG in the index pregnancy. Total gestation duration is inversely associated with E2, E3 and progesterone, whereas weight gain during pregnancy is inversely associated with progesterone and SHBG. In the US, pregnancies with female fetuses are characterized by significantly reduced progesterone. Pregnancy hormones are associated with several maternal, gestational and neonatal characteristics.

Summary Characteristics probably associated with the fetal hormonal milieu have recently been shown to increase (birth size indicators, prematurity, neonatal jaundice) or decrease (pregnancy toxaemia) breast cancer risk in the female offspring. However, it is unknown whether differences in pregnancy hormone levels may contribute to the marked geographical variation in breast cancer incidence. We have compared, in a highly standardized manner, pregnancy hormone levels in a population with high incidence and one with low incidence of breast cancer. Three hundred and four pregnant Caucasian women in Boston and 334 pregnant Chinese women in Shanghai were enrolled from March 1994 to October 1995. Levels of oestradiol, oestriol, prolactin, progesterone, human growth hormone, albumin and sex hormone-binding globulin were measured in maternal blood at weeks 16 and 27 of gestation and compared between the two study sites using non-parametric Wilcoxon's rank-sum test. Demographical, anthropometrical and pregnancy characteristics were ascertained through interview, and relevant variables concerning delivery and the newborn were abstracted from medical records and paediatric charts. During the first visit, median serum levels of all studied hormones were statistically significant, and in most instances substantially, higher among Chinese women, who have a low incidence of breast cancer, compared with American women, who have a high incidence of breast cancer. An analogous pattern was evident during the second visit, although the relative differences tended to be smaller. Further research is needed to identify lifestyle or other exogenous determinants of pregnancy hormone levels, as well as possible mechanisms by which they may influence carcinogenic processes in the breast and possibly other organs.

It is well established that microRNA (miRNA) expression profiles are altered in patients with polycystic ovary syndrome (PCOS). In addition, abnormal transforming growth factor beta (TGFB) signaling in granulosa cells is related to the pathological conditions of PCOS. However, the function of dysregulated miRNAs in PCOS is still unclear. In this study, we aimed to elucidate the roles of specific miRNAs in PCOS. We collected follicular fluid from 46 patients with PCOS and 32 healthy controls. Granulosa cells (GCs) were separated and the levels of six candidate miRNAs were determined by quantitative RT-PCR. The direct targets of three dysregulated miRNAs were predicted using bioinformatic tools and confirmed using a dual luciferase assay and immunoblotting. The biological function of three dysregulated miRNAs in primary GCs was determined using a cell proliferation assay and flow cytometry. We found that miR-423 expression was downregulated (P = 0.038), and the levels of miR-33b (P = 0.032) and miR-142 (P = 0.021) were upregulated in GCs from patients with PCOS, compared to controls. miR-423 directly repressed SMAD family member 7 (SMAD7) expression, while transforming growth factor beta receptor 1 (TGFBR1) was a direct target of both miR-33b and miR-142. An RNA oligonucleotide mixture containing miR-423 inhibitor, miR-33b mimic, and miR-142 mimic repressed TGFB signaling, promoted cell proliferation (P = 0.0098), repressed apoptosis (P = 0.027), and increased S phase cell numbers (P = 0.0036) in primary cultures of GCs, compared to the cells treated with a sequence scrambled control RNA oligonucleotide. This study unveiled the possible roles of three miRNAs in PCOS and might provide candidate biomarkers for PCOS diagnosis while in vivo functional studies, using transgenic or knockout mouse models, are expected to confirm the roles of dysregulated miRNAs in the pathogenesis of PCOS.

Valvular calcification (VC), a common complication of chronic kidney disease (CKD), is more prevalent in CKD patients than in normal individuals, which mostly occurs in the aortic and mitral valves. 1 The morbidity of VC among patients on dialysis is 28%-50%, 2 which severely affects the survival rate and living quality of CKD patients. Among patients undergoing long-term dialysis, the number of calcified valves has previously been shown to be associated with all-cause mortality and cardiovascular death. Accordingly, 1-year all-cause