Relaxin modulates human and rat hepatic myofibroblast function and ameliorates portal hypertension in vivo.

UNLABELLED: Active myofibroblast (MF) contraction contributes significantly to the increased intrahepatic vascular resistance that is the primary cause of portal hypertension (PHT) in cirrhosis. We sought proof of concept for direct therapeutic targeting of the dynamic component of PHT and markers of MF activation using short-term administration of the peptide hormone relaxin (RLN). We defined the portal hypotensive effect in rat models of sinusoidal PHT and the expression, activity, and function of the RLN-receptor signaling axis in human liver MFs. The effects of RLN were studied after 8 and 16 weeks carbon tetrachloride intoxication, following bile duct ligation, and in tissue culture models. Hemodynamic changes were analyzed by direct cannulation, perivascular flowprobe, indocyanine green imaging, and functional magnetic resonance imaging. Serum and hepatic nitric oxide (NO) levels were determined by immunoassay. Hepatic inflammation was assessed by histology and serum markers and fibrosis by collagen proportionate area. Gene expression was analyzed by quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and western blotting and hepatic stellate cell (HSC)-MF contractility by gel contraction assay. Increased expression of RLN receptor (RXFP1) was shown in HSC-MFs and fibrotic liver diseases in both rats and humans. RLN induced a selective and significant reduction in portal pressure in pathologically distinct PHT models, through augmentation of intrahepatic NO signaling and a dramatic reduction in contractile filament expression in HSC-MFs. Critical for translation, RLN did not induce systemic hypotension even in advanced cirrhosis models. Portal blood flow and hepatic oxygenation were increased by RLN in early cirrhosis. Treatment of human HSC-MFs with RLN inhibited contractility and induced an antifibrogenic phenotype in an RXFP1-dependent manner. CONCLUSION: We identified RXFP1 as a potential new therapeutic target for PHT and MF activation status.

Soluble ligands for NK cell receptors promote evasion of chronic lymphocytic leukemia cells from NK cell anti-tumor activity.

Natural killer (NK) cells are a major component of the anti-tumor immune response. NK cell dysfunctions have been reported in various hematologic malignancies, including chronic lymphocytic leukemia (CLL). Here we investigated the role of tumor cell-released soluble and exosomal ligands for NK cell receptors that modulate NK cell activity. Soluble CLL plasma factors suppressed NK cell cytotoxicity and down-regulated the surface receptors CD16 and CD56 on NK cells of healthy donors. The inhibition of NK cell cytotoxicity was attributed to the soluble ligand BAG6/BAT3 that engages the activating receptor NKp30 expressed on NK cells. Soluble BAG6 was detectable in the plasma of CLL patients, with the highest levels at the advanced disease stages. In contrast, NK cells were activated when BAG6 was presented on the surface of exosomes. The latter form was induced in non-CLL cells by cellular stress via an nSmase2-dependent pathway. Such cells were eliminated by lymphocytes in a xenograft tumor model in vivo. Here, exosomal BAG6 was essential for tumor cell killing because BAG6-deficient cells evaded immune detection. Taken together, the findings show that the dysregulated balance of exosomal vs soluble BAG6 expression may cause immune evasion of CLL cells.

COVID-19 and Domestic Violence: Economics or Isolation?

Recent studies estimate that the COVID-19 pandemic significantly increases reports of domestic violence in several countries. Using mobile device tracking data, city-level unemployment data, and new data on labor market conditions caused by the coronavirus pandemic, we isolate the effects of unemployment and staying at home on incidents of domestic violence. We find that unemployment decreases domestic violence after controlling for the degree to which people stay at home. We also provide evidence that staying at home increases domestic violence. However, we find that the effects of unemployment and staying at home are concentrated right after an initial shock from mid-March to mid-June 2020. Finally, we find that some labor market conditions linked to COVID-19, such as being prevented from looking for work due to the pandemic, decrease domestic violence, and these labor market effects are often gendered.

COVID-19, staying at home, and domestic violence.

We analyze how staying at home during the COVID-19 pandemic affects the rates of domestic violence in the U.S. Using police dispatch and crime data from 36 police and sheriff's departments and mobile device tracking data, we find that reported incidents of domestic violence increase as more people stay at home. Specifically, we estimate that staying at home due to COVID-19 increased domestic violence by over 5% on average from March 13 to May 24, 2020. This is consistent with a theory of exposure reduction, where victims and abusers stuck at home are more likely to fight.

New insights into the evolution of chorionic gonadotrophin.

The glycoprotein hormones luteinizing hormone (LH) and chorionic gonadotrophin (CG) are crucial for reproduction, as LH induces sex hormone production and ovulation, and CG is essential for the establishment of pregnancy and fetal male sexual differentiation. Both consist of two heterodimeric peptides of which the alpha-subunit is common to both hormones whereas the beta-subunit is hormone-specific. The CGB gene was derived from LHB by gene duplication and frame shift mutation that led to a read-through into the formerly 3'-untranslated region, giving rise to the carboxyl-terminal peptide. Owing to nucleotide changes within the 5'-region of CGB, a new transcriptional start site and regulatory region was gained. These changes led to the specific expression of CGB in the placenta and its decrease in the pituitary. Recent findings on gonadotrophins led to an extended model for the sequence of events in the evolution of the CGB gene in primates and its tissue-specific expression.

Chorionic gonadotropin beta-subunit gene expression in the marmoset pituitary is controlled by steroidogenic factor 1, early growth response protein 1, and pituitary homeobox factor 1.

In most mammals, the gonads are under the control of the pituitary gonadotropins LH and FSH. However, in the common marmoset monkey Callithrix jacchus, no LH is detectable in the pituitary but chorionic gonadotropin (CG) instead, normally produced in the placenta. This study investigated the mechanism of CGbeta subunit activation in the pituitary and why humans do not express CG in the pituitary. 5'-Rapid amplification of cDNA ends, EMSA, and promoter-driven luciferase assays performed with the gonadotropic LbetaT2 cells showed that marmoset monkey CGbeta is GnRH responsive and activated similar to human LHbeta by the transcription factors steroidogenic factor 1 (SF1), early growth response protein 1 (Egr1), and pituitary homeobox factor 1 (Pitx1) and displayed a transcriptional start site 7 bp upstream of exon 1. In contrast, the human CGbeta promoter displayed in the binding elements for pituitary homeobox factor 1 and early growth response protein 1 three consensus sequence mismatches, leading to very low activity that could be drastically increased by mutation to the consensus sequences. Vice versa, marmoset CGbeta promoter activity was reduced after introduction of the human CGbeta mismatches. An in vivo study in pregnant marmoset monkeys showed that during pregnancy, there is no significant decrease of pituitary CG production, contrasting human LH down-regulation. In conclusion, pituitary CG production is lacking in humans due to the absence of appropriate DNA-binding elements, which are present in marmosets, thereby enabling GnRH activation of expression. However, during pregnancy of marmosets, pituitary CG expression is not inhibited.

The histone deacetylase inhibitor LBH589 (panobinostat) modulates the crosstalk of lymphocytes with Hodgkin lymphoma cell lines.

Epigenetic changes have been implicated in the malignant phenotype of Hodgkin Reed Sternberg (HRS) cells in Hodgkin lymphoma (HL), where HRS survival and proliferation depends on the microenvironment. The histone-deacetylase (HDAC) inhibitor LBH589 (panobinostat) showed clinical efficacy but its impact on the HRS microenvironment is unclear. Hence, we analysed the effects of LBH589 on lymphocytes and also potential combination therapies. In lymphocyte-target cell killing assays, LBH589-treatment triggered an enhanced lymphocyte-dependent lysis of HL cells despite of mild lymphocytopenic effects. In co-culture experiments of lymphocytes with HL cells, LBH589 suppressed the IFNgamma-release but increased the TNFalpha secretion. Recombinant TNFalpha boosted the lymphocyte-dependent lysis of HL target cells. In HL cell lines, LBH589 induced cell death, autophagy, and an increase of MICA/B that are ligands to natural killer cell receptors. The combination of LBH589 with Brentuximab Vedotin was inefficient due to down-regulation of CD30 as a target. Combination with gemcitabine revealed highly significant effects, suggesting a potential combination for future therapy. Based on these data we suggest that LBH589 favourably modulates the cytokine network and lymphocyte activity in the HL microenvironment.

Stromal expression of decorin, Semaphorin6D, SPARC, Sprouty1 and Tsukushi in developing prostate and decreased levels of decorin in prostate cancer.

BACKGROUND AND AIM: During prostate development, mesenchymal-epithelial interactions regulate organ growth and differentiation. In adult prostate, stromal-epithelial interactions are important for tissue homeostasis and also play a significant role in prostate cancer. In this study we have identified molecules that show a mesenchymal expression pattern in the developing prostate, and one of these showed reduced expression in prostate cancer stroma. METHODOLOGY AND PRINCIPAL FINDINGS: Five candidate molecules identified by transcript profiling of developmental prostate mesenchyme were selected using a wholemount in situ hybridisation screen and studied Decorin (Dcn), Semaphorin6D (Sema6D), SPARC/Osteonectin (SPARC), Sprouty1 (Spry-1) and Tsukushi (Tsku). Expression in rat tissues was evaluated using wholemount in situ hybridisation (postnatal day (P) 0.5) and immunohistochemistry (embryonic day (E) E17.5, E19.5; P0.5; P6; 28 & adult). Four candidates (Decorin, SPARC, Spry-1, Tsukushi) were immunolocalised in human foetal prostate (weeks 14, 16, 19) and expression of Decorin was evaluated on a human prostate cancer tissue microarray. In embryonic and perinatal rats Decorin, Semaphorin6D, SPARC, Spry-1 and Tsukushi were expressed with varying distribution patterns throughout the mesenchyme at E17.5, E19.5, P0.5 and P6.5. In P28 and adult prostates there was either a decrease in the expression (Semaphorin6D) or a switch to epithelial expression of SPARC, and Spry-1, whereas Decorin and Tsukushi were specific to mesenchyme/stroma at all ages. Expression of Decorin, SPARC, Spry-1 and Tsukushi in human foetal prostates paralleled that in rat. Decorin showed mesenchymal and stromal-specific expression at all ages and was further examined in prostate cancer, where stromal expression was significantly reduced compared with non-malignant prostate. CONCLUSION AND SIGNIFICANCE: We describe the spatio-temporal expression of Decorin, Semaphorin6D, SPARC, Spry-1 and Tsukushi in developing prostate and observed similar mesenchymal expression patterns in rat and human. Additionally, Decorin showed reduced expression in prostate cancer stroma compared to non-malignant prostate stroma.

A novel two-promoter-one-gene system of the chorionic gonadotropin ß gene enables tissue-specific expression.

The New World monkey (NWM), Callithrix jacchus, a preferred model in medical research, displays an interesting endocrine regulation of reproduction: LH, the heterodimeric glycoprotein hormone, is functionally replaced by the chorionic gonadotropin (CG), a hormone indispensable for establishment of pregnancy in humans and normally expressed in the placenta. In the marmoset pituitary, the expression of the ß-subunit (CGB) gene is regulated similar to human LH ß-subunit, but its placental regulation is unknown. This study intended to decipher the underlying mechanism of tissue-specific expression of CGB in the marmoset placenta. We identified a new placental transcriptional start site, described a new, previously undiscovered exon, and define a novel placental core promoter in the marmoset CGB gene. This promoter contains a TATA box and binding sites for activating protein 2 and selective promoter factor 1, the latter acting synergistically by forming a regulation cassette. Differential first exon usage directed the tissue-specific expression. Methylation analyses revealed a tissue-specific pattern in the placental promoter indicating additional epigenetic regulation of gene expression. Our findings point toward a hitherto unknown evolutionary plasticity in the LH/CG hormonal system in NWM, which could be used as a model to study human CGB regulation in clinical pathologies.