Immunostaining of βA-Activin and Follistatin Is Decreased in HPV(+) Cervical Pre-Neoplastic and Neoplastic Lesions

The activin-follistatin system regulates several cellular processes, including differentiation and tumorigenesis. We hypothesized that the immunostaining of βA-activin and follistatin varies in neoplastic cervical lesions. Cervical paraffin-embedded tissues from 162 patients sorted in control (n = 15), cervical intraepithelial neoplasia (CIN) grade 1 (n = 38), CIN2 (n = 37), CIN3 (n = 39), and squamous cell carcinoma (SCC; n = 33) groups were examined for βA-activin and follistatin immunostaining. Human papillomavirus (HPV) detection and genotyping were performed by PCR and immunohistochemistry. Sixteen samples were inconclusive for HPV detection. In total, 93% of the specimens exhibited HPV positivity, which increased with patient age. The most detected high-risk (HR)-HPV type was HPV16 (41.2%) followed by HPV18 (16%). The immunostaining of cytoplasmatic βA-activin and follistatin was higher than nuclear immunostaining in all cervical epithelium layers of the CIN1, CIN2, CIN3, and SCC groups. A significant decrease (p < 0.05) in the cytoplasmic and nuclear immunostaining of βA-activin was detected in all cervical epithelial layers from the control to the CIN1, CIN2, CIN3, and SCC groups. Only nuclear follistatin immunostaining exhibited a significant reduction (p < 0.05) in specific epithelial layers of cervical tissues from CIN1, CIN2, CIN3, and SCC compared to the control. Decreased immunostaining of cervical βA-activin and follistatin at specific stages of CIN progression suggests that the activin-follistatin system participates in the loss of the differentiation control of pre-neoplastic and neoplastic cervical specimens predominantly positive for HPV.

The Mammary Gland: Basic Structure and Molecular Signaling during Development

The mammary gland is a compound, branched tubuloalveolar structure and a major characteristic of mammals. The mammary gland has evolved from epidermal apocrine glands, the skin glands as an accessory reproductive organ to support postnatal survival of offspring by producing milk as a source of nutrition. The mammary gland development begins during embryogenesis as a rudimentary structure that grows into an elementary branched ductal tree and is embedded in one end of a larger mammary fat pad at birth. At the onset of ovarian function at puberty, the rudimentary ductal system undergoes dramatic morphogenetic change with ductal elongation and branching. During pregnancy, the alveolar differentiation and tertiary branching are completed, and during lactation, the mature milk-producing glands eventually develop. The early stages of mammary development are hormonal independent, whereas during puberty and pregnancy, mammary gland development is hormonal dependent. We highlight the current understanding of molecular regulators involved during different stages of mammary gland development.

Activin A in Mammalian Physiology

Activins are dimeric glycoproteins belonging to the transforming growth factor beta superfamily and resulting from the assembly of two beta subunits, which may also be combined with alpha subunits to form inhibins. Activins were discovered in 1986 following the isolation of inhibins from porcine follicular fluid, and were characterized as ovarian hormones that stimulate follicle stimulating hormone (FSH) release by the pituitary gland. In particular, activin A was shown to be the isoform of greater physiological importance in humans. The current understanding of activin A surpasses the reproductive system and allows its classification as a hormone, a growth factor, and a cytokine. In more than 30 yr of intense research, activin A was localized in female and male reproductive organs but also in other organs and systems as diverse as the brain, liver, lung, bone, and gut. Moreover, its roles include embryonic differentiation, trophoblast invasion of the uterine wall in early pregnancy, and fetal/neonate brain protection in hypoxic conditions. It is now recognized that activin A overexpression may be either cytostatic or mitogenic, depending on the cell type, with important implications for tumor biology. Activin A also regulates bone formation and regeneration, enhances joint inflammation in rheumatoid arthritis, and triggers pathogenic mechanisms in the respiratory system. In this 30-yr review, we analyze the evidence for physiological roles of activin A and the potential use of activin agonists and antagonists as therapeutic agents.

Prognostic value of follistatin-like 3 in human invasive breast cancer

Follistatin-like 3 (FSTL3) binds and inactivates activin, a growth factor involved with cell growth and differentiation. We have previously shown FSTL3 overexpression in invasive breast cancers, but its clinical relevance remained unexplored. Here we evaluate FSTL3 as a prognostic tool and its relation with clinical and pathological features of breast cancer. A cohort of 154 women diagnosed with invasive breast cancer between 2008 and 2012 was followed up for 5 years. Tumor samples were processed by immunohistochemistry to detect FSTL3 expression in tumor epithelium. FSTL3 expression was classified semiquantitatively and tested for possible correlation with age, menopause status, stage, tumor histological type and grade, estrogen receptor, progesterone receptor, and HER2 expression. Survival plots with Kaplan-Mayer statistics were used to assess whether FSTL3 expression predicted disease-free survival. Our findings show that FSTL3 staining was unrelated to menopausal status, histological type, disease stage, or receptor profile. However, the intensity of FSTL3 immunostaining correlated inversely with tumor size (r = -0.366, p<0.001) and with nuclear grade (p<0.01). The intensity of FSTL3 expression in the tumoral epithelium was not predictive of the disease-free survival (p = 0.991, log-rank test), even though the follow-up length and the study size were sufficient to detect a significant reduction in disease-free survival among women with stage III-IV compared to stage I-II disease (p<0.001). FSTL3 expression in invasive breast cancer is inversely associated with tumor size and nuclear grade but it does not predict disease relapse in the short term.

Chorioamnionitis Induces a Specific Signature of Placental ABC Transporters Associated with an Increase of miR-331-5p in the Human Preterm Placenta

Background/Aims

The ATP-binding cassette (ABC) transporters mediate drug biodisposition and immunological responses in the placental barrier. In vitro infective challenges alter expression of specific placental ABC transporters. We hypothesized that chorioamnionitis induces a distinct pattern of ABC transporter expression.

Methods

Gene expression of 50 ABC transporters was assessed using TaqMan® Human ABC Transporter Array, in preterm human placentas without (PTD; n=6) or with histological chorioamnionitis (PTDC; n=6). Validation was performed using qPCR, immunohistochemistry and Western blot. MicroRNAs known to regulate P-glycoprotein (P-gp) were examined by qPCR.

Results

Up-regulation of ABCB9, ABCC2 and ABCF2 mRNA was detected in chorioamnionitis (p<0.05), whereas placental ABCB1 (P-gp; p=0.051) and ABCG2 (breast cancer resistance protein-BCRP) mRNA levels (p=0.055) approached near significant up-regulation. In most cases, the magnitude of the effect significantly correlated to the severity of inflammation. Upon validation, increased placental ABCB1 and ABCG2 mRNA levels (p<0.05) were observed. At the level of immunohistochemistry, while BCRP was increased (p<0.05), P-gp staining intensity was significantly decreased (p<0.05) in PTDC. miR-331-5p, involved in P-gp suppression, was upregulated in PTDC (p<0.01) and correlated to the grade of chorioamnionitis (p<0.01).

Conclusions

Alterations in the expression of ABC transporters will likely lead to modified transport of clinically relevant compounds at the inflamed placenta. A better understanding of the potential role of these transporters in the events surrounding PTD may also enable new strategies to be developed for prevention and treatment of PTD.

Genetic Architecture and Selection of Chinese Cattle Revealed by Whole Genome Resequencing

The bovine genetic resources in China are diverse, but their value and potential are yet to be discovered. To determine the genetic diversity and population structure of Chinese cattle, we analyzed the whole genomes of 46 cattle from six phenotypically and geographically representative Chinese cattle breeds, together with 18 Red Angus cattle genomes, 11 Japanese black cattle genomes and taurine and indicine genomes available from previous studies. Our results showed that Chinese cattle originated from hybridization between Bos taurus and Bos indicus. Moreover, we found that the level of genetic variation in Chinese cattle depends upon the degree of indicine content. We also discovered many potential selective sweep regions associated with domestication related to breed-specific characteristics, with selective sweep regions including genes associated with coat color (ERCC2, MC1R, ZBTB17, and MAP2K1), dairy traits (NCAPG, MAPK7, FST, ITFG1, SETMAR, PAG1, CSN3, and RPL37A), and meat production/quality traits (such as BBS2, R3HDM1, IGFBP2, IGFBP5, MYH9, MYH4, and MC5R). These findings substantially expand the catalogue of genetic variants in cattle and reveal new insights into the evolutionary history and domestication traits of Chinese cattle.

Transcriptome difference and potential crosstalk between liver and mammary tissue in mid-lactation primiparous dairy cows

Liver and mammary gland are among the most important organs during lactation in dairy cows. With the purpose of understanding both the different and the complementary roles and the crosstalk of those two organs during lactation, a transcriptome analysis was performed on liver and mammary tissues of 10 primiparous dairy cows in mid-lactation. The analysis was performed using a 4×44K Bovine Agilent microarray chip. The transcriptome difference between the two tissues was analyzed using SAS JMP Genomics using ANOVA with a false discovery rate correction (FDR). The analysis uncovered >9,000 genes differentially expressed (DEG) between the two tissues with a FDR<0.001. The functional analysis of the DEG uncovered a larger metabolic (especially related to lipid) and inflammatory response capacity in liver compared with mammary tissue while the mammary tissue had a larger protein synthesis and secretion, proliferation/differentiation, signaling, and innate immune system capacity compared with the liver. A plethora of endogenous compounds, cytokines, and transcription factors were estimated to control the DEG between the two tissues. Compared with mammary tissue, the liver transcriptome appeared to be under control of a large array of ligand-dependent nuclear receptors and, among endogenous chemical, fatty acids and bacteria-derived compounds. Compared with liver, the transcriptome of the mammary tissue was potentially under control of a large number of growth factors and miRNA. The in silico crosstalk analysis between the two tissues revealed an overall large communication with a reciprocal control of lipid metabolism, innate immune system adaptation, and proliferation/differentiation. In summary the transcriptome analysis confirmed prior known differences between liver and mammary tissue, especially considering the indication of a larger metabolic activity in liver compared with the mammary tissue and the larger protein synthesis, communication, and proliferative capacity in mammary tissue compared with the liver. Relatively novel is the indication by the data that the transcriptome of the liver is highly regulated by dietary and bacteria-related compounds while the mammary transcriptome is more under control of hormones, growth factors, and miRNA. A large crosstalk between the two tissues with a reciprocal control of metabolism and innate immune-adaptation was indicated by the network analysis that allowed uncovering previously unknown crosstalk between liver and mammary tissue for several signaling molecules.

Possible involvement of inflammatory/reparative processes in the development of uterine fibroids

Uterine leiomyomas are benign tumors in the smooth muscle layer of the uterus. The most common histological type is the "usual leiomyoma", characterized by overexpression of ECM proteins, whereas the "cellular type" has higher cellular content. Our objective is to investigate the involvement of inflammatory and reparative processes in leiomyoma pathobiology. Using a morphological approach, we investigate the presence of inflammatory cells. Next, we determine the localization of the ECM, the presence/absence of fibrotic cells via α-sma and desmin and the immunohistochemical profile of the mesenchymal cells with respect to CD34. Finally, we explore the effect of inflammatory mediators (TNF-α, IL-1β, IL-6, IL-15, GM-CSF and IFN-γ) on pro-fibrotic factor activin A mRNA expression in vitro. Higher numbers of macrophages were found inside and close to leiomyomas as compared to the more distant myometrium. Cellular leiomyomas showed more macrophages and mast cells than the "usual type". Inside the fibroid tissue, we found cells positive for α-sma, but negative for desmin and a large amount of collagen surrounding the nodule, suggestive of myofibroblasts producing ECM. In the myometrium and leiomyomas of the "usual type", we identified numerous CD34+ fibroblasts, which are known to give rise to myofibroblasts upon loss of CD34 expression. In leiomyomas of the "cellular type", stromal fibroblasts were CD34-negative. Finally, we found that TNF-α increased activin A mRNA in myometrial and leiomyoma cells. In conclusion, this study demonstrates the presence of inflammatory cells in uterine leiomyomas, which may contribute to excessive ECM production, tissue remodeling and leiomyoma growth.

An interpretive review of selective sweep studies in Bos taurus cattle populations: identification of unique and shared selection signals across breeds

This review compiles the results of 21 genomic studies of European Bos taurus breeds and thus provides a general picture of the selection signatures in taurine cattle identified by genome-wide selection-mapping scans. By performing a comprehensive summary of the results reported in the literature, we compiled a list of 1049 selection sweeps described across 37 cattle breeds (17 beef breeds, 14 dairy breeds, and 6 dual-purpose breeds), and four different beef-vs.-dairy comparisons, which we subsequently grouped into core selective sweep (CSS) regions, defined as consecutive signals within 1 Mb of each other. We defined a total of 409 CSSs across the 29 bovine autosomes, 232 (57%) of which were associated with a single-breed (Single-breed CSSs), 134 CSSs (33%) were associated with a limited number of breeds (Two-to-Four-breed CSSs) and 39 CSSs (9%) were associated with five or more breeds (Multi-breed CSSs). For each CSS, we performed a candidate gene survey that identified 291 genes within the CSS intervals (from the total list of 5183 BioMart-extracted genes) linked to dairy and meat production, stature, and coat color traits. A complementary functional enrichment analysis of the CSS positional candidates highlighted other genes related to pathways underlying behavior, immune response, and reproductive traits. The Single-breed CSSs revealed an over-representation of genes related to dairy and beef production, this was further supported by over-representation of production-related pathway terms in these regions based on a functional enrichment analysis. Overall, this review provides a comparative map of the selection sweeps reported in European cattle breeds and presents for the first time a characterization of the selection sweeps that are found in individual breeds. Based on their uniqueness, these breed-specific signals could be considered as “divergence signals,” which may be useful in characterizing and protecting livestock genetic diversity.

Go with the flow-biology and genetics of the lactation cycle

Lactation is a dynamic process, which evolved to meet dietary demands of growing offspring. At the same time, the mother's metabolism changes to meet the high requirements of nutrient supply to the offspring. Through strong artificial selection, the strain of milk production on dairy cows is often associated with impaired health and fertility. This led to the incorporation of functional traits into breeding aims to counteract this negative association. Potentially, distributing the total quantity of milk per lactation cycle more equally over time could reduce the peak of physiological strain and improve health and fertility. During lactation many factors affect the production of milk: food intake; digestion, absorption, and transportation of nutrients; blood glucose levels; activity of cells in the mammary gland, liver, and adipose tissue; synthesis of proteins and fat in the secretory cells; and the metabolic and regulatory pathways that provide fatty acids, amino acids, and carbohydrates. Whilst the endocrine regulation and physiology of the dynamic process of milk production seems to be understood, the genetics that underlie these dynamics are still to be uncovered. Modeling of longitudinal traits and estimating the change in additive genetic variation over time has shown that the genetic contribution to the expression of a trait depends on the considered time-point. Such time-dependent studies could contribute to the discovery of missing heritability. Only very few studies have estimated exact gene and marker effects at different time-points during lactation. The most prominent gene affecting milk yield and milk fat, DGAT1, exhibits its main effects after peak production, whilst the casein genes have larger effects in early lactation. Understanding the physiological dynamics and elucidating the time-dependent genetic effects behind dynamically expressed traits will contribute to selection decisions to further improve productive and healthy breeding populations.

Expression, localization and control of activin A release from human umbilical vein endothelial cells

Activin-A is a member of the TGFβ superfamily found in maternal and umbilical cord blood throughout gestation. We investigated whether human umbilical vein endothelial cells (HUVEC) express activin-A in vivo and tested the effects of vasoactive (endothelin-1), pro-inflammatory (interferon-γ, interleukin-8) and anti-inflammatory (dexamethasone, urocortin) factors on activin-A release by isolated HUVEC in vitro. Activin βA subunit protein and mRNA were strongly localized in the endothelial cells of umbilical veins and were also detectable in scattered cells of the cord connective tissue. Dimeric activin-A was detected in the HUVEC culture medium at picomolar concentrations. Activin-A release by HUVEC decreased after cell incubation with urocortin (p < 0.01), whereas no effect was observed with interleukin-8, interferon-γ, endothelin-1 or dexamethasone. In summary, activin-A is present in the human umbilical vein endothelium in vivo and is produced and released by isolated HUVEC. Activin-A secretion is inhibited in vitro by urocortin, a neuropeptide with predominantly anti-inflammatory action.

A novel highly divergent protein family identified from a viviparous insect by RNA-seq analysis: a potential target for tsetse fly-specific abortifacients

In tsetse flies, nutrients for intrauterine larval development are synthesized by the modified accessory gland (milk gland) and provided in mother's milk during lactation. Interference with at least two milk proteins has been shown to extend larval development and reduce fecundity. The goal of this study was to perform a comprehensive characterization of tsetse milk proteins using lactation-specific transcriptome/milk proteome analyses and to define functional role(s) for the milk proteins during lactation. Differential analysis of RNA-seq data from lactating and dry (non-lactating) females revealed enrichment of transcripts coding for protein synthesis machinery, lipid metabolism and secretory proteins during lactation. Among the genes induced during lactation were those encoding the previously identified milk proteins (milk gland proteins 1-3, transferrin and acid sphingomyelinase 1) and seven new genes (mgp4-10). The genes encoding mgp2-10 are organized on a 40 kb syntenic block in the tsetse genome, have similar exon-intron arrangements, and share regions of amino acid sequence similarity. Expression of mgp2-10 is female-specific and high during milk secretion. While knockdown of a single mgp failed to reduce fecundity, simultaneous knockdown of multiple variants reduced milk protein levels and lowered fecundity. The genomic localization, gene structure similarities, and functional redundancy of MGP2-10 suggest that they constitute a novel highly divergent protein family. Our data indicates that MGP2-10 function both as the primary amino acid resource for the developing larva and in the maintenance of milk homeostasis, similar to the function of the mammalian casein family of milk proteins. This study underscores the dynamic nature of the lactation cycle and identifies a novel family of lactation-specific proteins, unique to Glossina sp., that are essential to larval development. The specificity of MGP2-10 to tsetse and their critical role during lactation suggests that these proteins may be an excellent target for tsetse-specific population control approaches.

The role of activin in mammary gland development and oncogenesis

TGFβ contributes to mammary gland development and has paradoxical roles in breast cancer because it has both tumor suppressor and tumor promoter activity. Another member of the TGFβ superfamily, activin, also has roles in the developing mammary gland, but these functions, and the role of activin in breast cancer, are not well characterized. TGFβ and activin share the same intracellular signaling pathways, but divergence in their signaling pathways are suggested. The purpose of this review is to compare the spatial and temporal expression of TGFβ and activin during mammary gland development, with consideration given to their functions during each developmental period. We also review the contributions of TGFβ and activin to breast cancer resistance and susceptibility. Finally, we consider the systemic contributions of activin in regulating obesity and diabetes; and the impact this regulation has on breast cancer. Elevated levels of activin in serum during pregnancy and its influence on pregnancy associated breast cancer are also considered. We conclude that evidence demonstrates that activin has tumor suppressing potential, without definitive indication of tumor promoting activity in the mammary gland, making it a good target for development of therapeutics.