The function of BAP18 on modulation of androgen receptor action in luteinized granulosa cells from normal weight women with and without PCOS

Modulation of the RAC1/MAPK/ERK signalling pathway by farnesyl diphosphate synthase regulates granulosa cells proliferation in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a complex gynaecological endocrine disease that occurs in women of childbearing age. The pathogenesis of PCOS is still unclear and further exploration is needed. Here, proteomic analysis indicated that the expression of farnesyl diphosphate synthase (FDPS) protein in ovarian tissue of PCOS mice was significantly decreased. The purpose of this study is to investigate the relationship between potential biomarkers of PCOS and granulosa cells (GCs) function. The mechanisms by which FDPS affected the proliferation of granulosa cells were also explored both in vitro and in vivo. We found that knockdown of FDPS inhibited the proliferation of KGN (human ovarian granulosa cell line), while overexpression of FDPS had the opposite effect. FDPS activated Rac1 (Rac Family Small GTPase 1) activity and regulated MAPK/ERK signalling pathway, which affecting the proliferation of KGN cells significantly. In addition, treatment with the adeno-associated virus (AAV)-FDPS reverses the dehydroepiandrosterone (DHEA)-induced PCOS-phenotype in mice. Our data indicated that FDPS could regulate the proliferation of ovarian GCs by modulating MAPK/ERK (mitogen-activated protein kinase/extracellular regulated protein kinases) pathway via activating Rac1 activity. These findings suggest that FDPS could be of great value for the regulation of ovarian granulosa cell function and the treatment of PCOS.

BAP18 facilitates CTCF-mediated chromatin accessible to regulate enhancer activity in breast cancer

The estrogen receptor alpha (ERα) signaling pathway is a crucial target for ERα-positive breast cancer therapeutic strategies. Co-regulators and other transcription factors cooperate for effective ERα-related enhancer activation. Recent studies demonstrate that the transcription factor CTCF is essential to participate in ERα/E2-induced enhancer transactivation. However, the mechanism of how CTCF is achieved remains unknown. Here, we provided evidence that BAP18 is required for CTCF recruitment on ERα-enriched enhancers, facilitating CTCF-mediated chromatin accessibility to promote enhancer RNAs transcription. Consistently, GRO-seq demonstrates that the enhancer activity is positively correlated with BAP18 enrichment. Furthermore, BAP18 interacts with SMARCA1/BPTF to accelerate the recruitment of CTCF to ERα-related enhancers. Interestingly, BAP18 is involved in chromatin accessibility within enhancer regions, thereby increasing enhancer transactivation and enhancer-promoter looping. BAP18 depletion increases the sensitivity of anti-estrogen and anti-enhancer treatment in MCF7 cells. Collectively, our study indicates that BAP18 coordinates with CTCF to enlarge the transactivation of ERα-related enhancers, providing a better understanding of BAP18/CTCF coupling chromatin remodeling and E-P looping in the regulation of enhancer transcription.

Role and mechanism of the p-JAK2/p-STAT3 signaling pathway in follicular development in PCOS rats

OBJECTIVE

To identify the association between the phosphorylated Janus kinase 2/phosphorylated signal transducer and activator of transcription (p-JAK2/p-STAT3) signaling pathway and follicular development in polycystic ovary syndrome (PCOS) rats, and explore the underlying mechanism. To evaluate the role of exogenous JAK2 inhibitor AG490 in the model and the associations among luteinizing hormone/choriogonadotropin receptor (LHCGR), follicle-stimulating hormone receptor (FSHR), cytochrome P450 17α (CYP17a), cytochrome P450 19 (CYP19), and PCOS.

RESULTS

Rat models of PCOS was established. PCOS rats were intraperitoneally treated with double-distilled water (ddH2O)/DMSO/AG490. The rate of ovarian morphological recovery in the AG490 group was significantly higher compared with the DMSO group (83.3 % vs 9.1 %, X² = 12.68, P < 0.001). Moreover, the short in the time the estrous cycle was resumed in the AG490 group (hazard ratio = 16.32, P < 0.001) compared with the DMSO group. Compared with the controls, p-JAK2, p-STAT3, LHCGR, and CYP17a expression levels were increased whereas that of FSHR and CYP19 were decreased in the ovaries of PCOS rats. However, an opposite trend was observed after treatment with AG490. Software prediction revealed that the p-STAT3 bound to the promoter regions of LHCGR, FSHR, CYP17a, and CYP19 genes. This finding was confirmed by results of correlation analysis (R = 0.834, -0.836, 0.875 and -0.712, respectively, all P < 0.001).

CONCLUSION

This study demonstrated that the p-JAK2/p-STAT3 signaling pathway was involved in follicular development in PCOS rats by upregulating LHCGR and CYP17a expression, and downregulating that of FSHR and CYP19. AG490 treatment exerted beneficial effects. LHCGR, FSHR, CYP17a, and CYP19 are candidate genes associated with follicular development in PCOS rats.

Chromatin complexes subunit BAP18 promotes triple-negative breast cancer progression through transcriptional activation of oncogene S100A9

Triple-negative breast cancer (TNBC) is a highly lethal disease due to aggressive clinical phenotype and the lack of validated therapeutic targets. Our recent quantitative proteomic analysis of 90 cases of TNBC tissues and 72 cases of matched adjacent normal tissues revealed that the expression levels of BPTF-associated protein of 18 KDa (BAP18), a component of the MLL1 and NURF chromatin complexes, were upregulated in TNBC tissues relative to normal tissues. However, the biological function and the underlying mechanism of BAP18 in TNBC progression remain unexplored. Here, we report that BAP18 promoted TNBC cell proliferation, migration, and invasion in vitro and xenograft tumor growth and lung colonization in vivo. Mechanistic investigations revealed that S100 calcium-binding protein A9 (S100A9), a member of the S100 protein family that is frequently upregulated in breast tumors and acts as an oncogenic driver in breast cancer progression, was a downstream target gene of BAP18. BAP18 was recruited to histone H3 trimethylation at lysine 4 (H3K4me3)-marked promoter of S100A9 and enhanced its promoter activities. Notably, knockdown of BAP18 by short hairpin RNA in TNBC cells suppressed xenograft tumor growth in mice, the noted effect was partially reverted by re-expression of S100A9 in BAP18-depleted cells. Taken together, these results suggest that BAP18 promotes TNBC progression through, at least in part, transcriptional activation of oncogene S100A9, and represents a potential therapeutic target for TNBC.

Exposure of childbearing-aged female to phthalates through the use of personal care products in China: An assessment of absorption via dermal and its risk characterization

Phthalates (PAEs) are widely used in personal care products (PCPs) and skin care packaging materials. Through national representative sampling, 328 childbearing-aged females in China were investigated by questionnaire, whose contact factors for 30 cosmetic products were collected. According to the daily exposure method and adverse cumulative effects of PAE exposure on female reproduction, we derived the ERα, ERβ binding, and AR anti-androgenic effects. The utilization rates of acne cleanser, acne cream, cleanser (non-acne), and cream (non-acne) in volunteers were 21.90%, 22.22%, 51.63%, and 51.96%, respectively. Examining the data for PAEs in PCPs, the content of DBP (dibutyl phthalate) in them was significantly higher for tubes (0.26 ± 0.05 μg/g) and other packaging (pump type and metal tube) (0.25 ± 0.03 μg/g) than bowl (0.17 ± 0.04 μg/g). The DBP content of acne cream (0.27 ± 0.03 μg/g) was significantly higher than that of non-acne cream (0.17 ± 0.03 μg/g); likewise, there was significantly more DEHP (di (2-ethylhexyl) phthalate) in acne cleanser (0.87 ± 0.15 μg/g) than non-acne cleanser (0.64 ± 0.36 μg/g). Students and office worker were the main consumers of PCPs; however, among all occupation groups, the daily exposure dose of PCPs for workers was highest (mean = 0.0004, 0.0002, 0.0009 μg/kg bw/day for DEP (diethyl phthalate), DBP, and DEHP, respectively). The cumulative indices of PAEs' exposure revealed that the level of ERα and ERβ binding and AR anti-androgenic effects in workers was respectively 0.4935, 0.0186, and 0.2411 μg/kg bw/day. The risk index (HI_TDI and HI_RfDs) of DEP, DBP, and DEHP was lower than their corresponding reference value (hazard index <1), but using PCPs may cause potential health risks. Therefore, we should pay attention to the adverse effects of PAEs on female reproductive functioning, especially the cumulative exposure of females of childbearing age.