A Proteomic Approach for the Identification of Up-Regulated Proteins Involved in the Metabolic Process of the Leiomyoma

Integrated Proteotranscriptomics of Human Myometrium in Labor Landscape Reveals the Increased Molecular Associated With Inflammation Under Hypoxia Stress

During labor, a variety of coordinated physiological and biochemical events cause the myometrium to transition from a quiescent to contractile state; the molecular mechanisms responsible for this transition, however, remain unclear. To better understand this transition at a molecular level, the global transcriptome and proteome of human myometrial samples in labor and those not in labor were investigated through RNA sequencing (RNA-seq) and quantitative liquid chromatography–tandem mass spectrometry (LC-MS/MS) via data-independent acquisition (DIA) and parallel reaction monitoring (PRM) methods. Furthermore, an integrated proteotranscriptomic analysis was performed to explore biological processes and pathway alterations during labor; this analysis identified 1,626 differentially expressed mRNAs (1,101 upregulated, 525 downregulated) and 135 differentially expressed proteins (97 upregulated, 38 downregulated) in myometrium between nonlabor and in labor groups. The comprehensive results of these analyses showed that the upregulated mRNAs and proteins increased inflammation under hypoxia stress in the myometrium under labor, and related proteins and cytokines were validated by PRM and Luminex assays. Our study confirmed the biological process of inflammation and hypoxia in laboring myometrium at the transcriptome and proteome levels and provided recourse to discover new molecular and biological changes during labor.

Effects of a High-Grain Diet With a Buffering Agent on Milk Protein Synthesis in Lactating Goats

Chinese dairy industries have developed rapidly, providing consumers with high-quality sources of nutrition. However, many problems have also appeared during the development process, especially the low quality of milk. To improve milk quality, a large amount of concentrated feed is usually added to the diet within a certain period of time, which increases the milk production to a certain extent. However, long-term feeding with high-concentration feed can lead to subacute rumen acidosis. Therefore, the present study aimed to determine the effect of adding a buffer on subacute rumen acidosis, and the improvement of milk production and milk quality. We also aimed to study the mechanism of promoting mammary gland lactation. A total of 12 healthy mid-lactating goats were randomly divided into two groups, they were high-grain diet group (Control) and buffering agent group. To understand the effects of high-grain diets with buffers on amino acids in jugular blood and the effects of amino acids on milk protein synthesis, Milk-Testing™ Milkoscan 4000, commercial kits, and high-performance liquid chromatography (HPLC) measurements were integrated with the milk protein rate, the amino acid concentration in jugular venous blood samples, quantitative real-time PCR, comparative proteomics, and western blotting to study differentially expressed proteins and amino acids in mammary gland tissues of goats fed high-grain diets. Feeding lactating goats with buffering agent increased the percentage of milk protein in milk, significantly increased the amino acid content of jugular blood (p < 0.05), and increase the amino acid transporter levels in the mammary gland. Compared with the high-grain group, 2-dimensional electrophoresis technology, matrix-assisted laser desorption/ionization-time of flight/time of flight proteomics analyzer, and western blot analysis further verified that the expression levels of beta casein (CSN2) and lactoferrin (LF) proteins in the mammary glands of lactating goats were higher when fed a high-grain diets and buffers. The mechanism of increased milk protein synthesis was demonstrated to be related to the activation of mammalian target of rapamycin (mTOR) pathway signals.

Interactome Analysis of the Differentially Expressed Proteins in Uterine Leiomyoma

BACKGROUND

Recent advances in proteomics present enormous opportunities to discover proteome related disparities and thus understanding the molecular mechanisms related to a disease. Uterine leiomyoma is a benign monoclonal tumor, located in the pelvic region, and affecting 40% of reproductive aged female.

OBJECTIVE

Identification and characterization of the differentially expressed proteins associated with leiomyogenesis by comparing uterine leiomyoma and normal myometrium.

METHODS

Paired samples of uterine leiomyoma and adjacent myometrium retrieved from twenty-five females suffering from uterine leiomyoma (n=50) were submitted to two-dimensional electrophoresis (2-DE), matrixassisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and to reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

Comparison of protein patterns revealed seven proteins with concordantly increased spot intensities in leiomyoma samples. E3 ubiquitin-protein ligase MIB2 (MIB2), Mediator of RNA polymerase II transcription subunit 10 (MED10), HIRA-interacting protein (HIRP3) and Fatty acid binding protein brain (FABP7) were found to be upregulated. While, Biogenesis of lysosome-related organelles complex 1 subunit 2 (BL1S2), Shadow of prion protein (SPRN) and RNA binding motif protein X linked like 2 (RMXL2) were found to be exclusively present in leiomyoma sample. The expression modulations of the corresponding genes were further validated which corroborated with the 2-DE result showing significant upregulation in leiomyoma. We have generated a master network showing the interactions of the experimentally identified proteins with their close neighbors and further scrutinized the network to prioritize the routes leading to cell proliferation and tumorigenesis.

CONCLUSION

This study highlights the importance of identified proteins as potential targets for therapeutic purpose. This work provides an insight into the mechanism underlying the overexpression of the proteins but warrants further investigations.

Effects of High-Grain Diet With Buffering Agent on the Hepatic Metabolism in Lactating Goats

To gain insight on the effects of a high-grain diet with buffering agent on liver metabolism and the changes of plasma biochemical parameters and amino acids in hepatic vein and portal vein, commercial kit and high performance liquid chromatography (HPLC) were applied to determine the concentration of amino acids of hepatic vein and portal vein blood samples, quantitative real-time PCR and comparative proteomic approach was employed to investigate proteins differentially expressed in liver in lactating dairy goats feeding high-grain diet with buffering agent or only high-grain diet. Results showed that feeding high-grain diet with buffering agent to lactating dairy goats could outstanding increase amino acid content of Gln (p < 0.01), and the amino acid contents of Arg and Tyr in BG were significantly higher (p < 0.05) than that in HG. After adding the buffering agent, the metabolism of amino acids in the liver were changed and most of the amino acids were increasingly synthesized and decreasingly consumed in the liver. In addition, 46 differentially expressed protein spots (≥1.5-fold changed) were detected in buffering group vs. control group using 2-DE technique and MALDI-TOF/TOF proteomics analyzer. Of these, 24 proteins showed increased expression and 22 proteins showed decreased expression in the buffer group vs. control group. Data on Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis reveals that the high-grain diet with buffering agent alter the expression of proteins related to amino acids metabolism and glycometabolism. In addition, the results conclude that feeding high-grain diet with buffering agent can strengthen anti-oxidant capacity, stress ability, slow down urea metabolism, and alter amino acid metabolism as well as glycometabolism in the liver through different detection methods including proteomic analysis, real-time PCR analysis and biochemical analysis.

Phosphoproteins Involved in the Inhibition of Apoptosis and in Cell Survival in the Leiomyoma

Uterine leiomyomas are benign smooth muscle cell tumors originating from the myometrium. In this study we focus on leiomyoma and normal myometrium phosphoproteome, to identify differentially phosphorylated proteins involved in tumorigenic signaling pathways, and in anti-apoptotic processes and cell survival. We obtained paired tissue samples of seven leiomyomas and adjacent myometria and analyzed the phosphoproteome by two-dimensional gel electrophoresis (2-DE) combined with immobilized metal affinity chromatography (IMAC) and Pro-Q Diamond phosphoprotein gel stain. We used mass spectrometry for protein identification and Western blotting for 2-DE data validation. Quantities of 33 proteins enriched by the IMAC approach were significantly different in the leiomyoma if compared to the myometrium. Bioinformatic analysis revealed ten tumorigenic signaling pathways and four phosphoproteins involved in both the inhibition of apoptosis and cell survival. Our study highlights the involvement of the phosphoproteome in leiomyoma growth. Further studies are needed to understand the role of phosphorylation in leiomyoma. Our data shed light on mechanisms that still need to be ascertained, but could open the path to a new class of drugs that not only can block the growth, but could also lead to a significant reduction in tumor size.

The mitochondrial DNA 4977-bp deletion and copy number alteration in Han Chinese samples with uterine fibroids

Uterine fibroids (UFs) are the most common benign neoplasms, but their pathogenesis is not completely understood. Thus far, alterations in the mitochondrial DNA (mtDNA) content and the mtDNA 4977-bp deletion level in UFs, as well as the corresponding nontumorous tissue, have remained elusive. To test whether large mtDNA deletions and mtDNA content are involved in the pathogenesis of UFs, a total of 309 UF tissues and 28 paired adjacent myometrium from 270 UF patients were enrolled for the analysis of large mtDNA deletions and mtDNA content through the use of nested PCR and qPCR techniques, respectively. In our samples, a 4977-bp deletion was identified: 36 out of 309 UF tissues (11.56%) and 15 out of 28 (53.57%) paired adjacent myometrium were detected to harbor the 4977-bp deletion. In addition, a novel 4838-bp mtDNA deletion was identified in three UF tissues, and other different sizes of deleted fragments (4910, 4926, 5135-bp) were also found in UFs for the first time. Furthermore, older age was significantly associated with an mtDNA large deletion in the paired adjacent myometrium. We also found that increased mtDNA content and higher expression of ND1 occurred in solitary fibroids compared to adjacent myometrium. In conclusion, we identified a lower frequency of mtDNA large deletions and some novel large deletion in UFs for the first time. Furthermore, there was a general increase of mtDNA copy number during solitary UF development. Although the definite mechanism by which mtDNA was altered is supposed to be further confirmed, it will be helpful for further studies on the pathological mechanism of UFs.

Dysregulated chaperones associated with cell proliferation and negative apoptosis regulation in the uterine leiomyoma

Uterine leiomyomas are benign smooth muscle cell tumors that originate from the myometrium. In this study we focus on dysregulated chaperones associated with cell proliferation and apoptosis. Paired tissue samples of 15 leiomyomas and adjacent myometria were obtained and analyzed by two-dimensional gel electrophoresis (2-DE). Mass spectrometry was used for protein identification and western blotting for 2-DE data validation. The values of 6 chaperones were found to be significantly different in the leiomyoma when compared with the myometrium. A total of 4 proteins were upregulated in the leiomyoma and 2 proteins were downregulated. Calreticulin and 78 kDa glucose-regulated protein were further validated by western blotting because the first is considered a marker of cell proliferation, while the second protects against apoptotic cell death. In addition, we also validated the two downregulated proteins heat shock protein β-1 and heat shock 70 kDa protein 1A. Our study shows the existence of a dysregulation of chaperone proteins associated with leiomyoma development. Functional studies are needed to ascertain the role of these chaperones in the leiomyoma. This may be crucial for the further development of specific inhibitors against the activity of these proteins in order to block the growth of the leiomyoma.

A proteomic approach for the identification of biomarkers in endometrial cancer uterine aspirate

Endometrial cancer arises from the endometrium. It has a slow progression and a reported survival rate of 75%. The identification of soluble biomarkers in the uterine aspirate may be very useful for its early diagnosis. Uterine aspirates from 10 patients with endometrial cancer and 6 non-endometrial cancer controls were analyzed by two-dimensional gel electrophoresis coupled with mass spectrometry and western blotting for data verification. A total of 25 proteins with fold change in %V ≥2 or ≤0.5 in intensity were observed to change significantly (P<0.05). From the discovery phase, four proteins (costars family protein ABRACL, phosphoglycerate mutase 2, fibrinogen beta chain, annexin A3) were found to be present in the uterine aspirate of endometrial cancers and not in healthy aspirates. Western blotting verification data demonstrated that costars family protein ABRACL, phosphoglycerate mutase 2 were present only in endometrial cancer uterine aspirate while fibrinogen beta chain, annexin A3 were also present in healthy aspirates. To our knowledge, phosphoglycerate mutase 2 has not been previously associated with endometrial cancer. In this study we demonstrate that uterine aspirates are a promising biological fluid in which to identify endometrial cancer biomarkers. In our opinion proteins like costars family protein ABRACL and phosphoglycerate mutase 2 have a great potential to reach the clinical phase after a validation phase.

Pathobiology of myomatosis uteri: the underlying knowledge to support our clinical practice

INTRODUCTION

Uterine myomatosis, a benign condition, is the most common indication for hysterectomies worldwide, affecting the reproductive goals and quality of health of women. However, gynecologists have been provided with interesting insights on its pathobiology, which are the basis for uterine-preserving therapies. The aim of this paper is to discuss the latest evidence on these mechanisms and its importance in the clinical practice.

METHOD

A comprehensive literature search was made in Pubmed, Medline, the Cochrane Library, Orbis plus and Google Scholar for articles related to the epidemiological, biological, and genetic bases.

RESULTS

There is extensive evidence that genetic, epigenetic, hormonal, environmental, proinflamatory, angiogenetic, and growing factors are involved in the biology of myomatosis. Such factors are capable of activating and promoting inhibitory signaling pathways leading to initiation, development, and regression of myomata through changes in myometrial cells and myomata fibers, such as cellular proliferation, differentiation, apoptosis, angiogenesis, and changes in the surrounding environment.

CONCLUSION

A good understanding of the pathobiologic mechanisms of myomatosis gives reasons to physicians to elect conservative or combined therapies, and allow affected women to receive an individualized management, according to age, reproduction desire, and clinical condition.

Identification of proteins with different abundance associated with cell migration and proliferation in leiomyoma interstitial fluid by proteomics

Uterine leiomyoma is the most common female reproductive tract benign tumor. Little is known about protein composition and changes in the leiomyoma interstitial fluid (IF). The present study focused on changes in protein abundance in the IF of leiomyoma. Leiomyoma IFs and adjacent myometrial IFs were obtained and analyzed by two-dimensional electrophoresis (2-DE) coupled with mass spectrometry and western blotting for 2-DE data validation. A total of 25 unique proteins were observed to change significantly (P<0.05). Of these proteins with different abundance, 22 had not been previously identified in leiomyoma IF. In silico analysis predicted that three of these proteins were secreted via classical mechanisms, while 22 were secreted via non-classical mechanisms. Ingenuity Pathway Analysis identified 17 proteins associated with cellular migration and proliferation. Among these, phosphoglycerate mutase 1 had not been previously associated with leiomyoma. The abundance of seven proteins was further validated by western blotting. A comparative proteomic approach identified a number of proteins associated with cellular migration and proliferation, with changes in abundance in IF likely to be involved in tumor development. Further studies will be required to investigate the role of these proteins in leiomyoma IF and their possible association with tumor development and growth.