Transforming growth factor-β regulates the expression of anosmin (KAL-1) in human retinal pigment epithelial cells

The multifaceted links between hearing loss and chronic kidney disease

Hearing loss affects nearly 1.6 billion people and is the third-leading cause of disability worldwide. Chronic kidney disease (CKD) is also a common condition that is associated with adverse clinical outcomes and high health-care costs. From a developmental perspective, the structures responsible for hearing have a common morphogenetic origin with the kidney, and genetic abnormalities that cause familial forms of hearing loss can also lead to kidney disease. On a cellular level, normal kidney and cochlea function both depend on cilial activities at the apical surface, and kidney tubular cells and sensory epithelial cells of the inner ear use similar transport mechanisms to modify luminal fluid. The two organs also share the same collagen IV basement membrane network. Thus, strong developmental and physiological links exist between hearing and kidney function. These theoretical considerations are supported by epidemiological data demonstrating that CKD is associated with a graded and independent excess risk of sensorineural hearing loss. In addition to developmental and physiological links between kidney and cochlear function, hearing loss in patients with CKD may be driven by specific medications or treatments, including haemodialysis. The associations between these two common conditions are not commonly appreciated, yet have important implications for research and clinical practice.

The Aflibercept-Induced MicroRNA Profile in the Vitreous of Proliferative Diabetic Retinopathy Patients Detected by Next-Generation Sequencing

Purpose: Vascular endothelial growth factor-A (VEGF-A) is an important pathogenic factor in proliferative diabetic retinopathy (PDR), and aflibercept (Eylea) is one of the widely used anti-VEGF agents. This study investigated the microRNA (miRNA) profiles in the vitreous of 5 idiopathic macular hole patients (non-diabetic controls), 5 untreated PDR patients (no-treatment group), and 5 PDR patients treated with intravitreal aflibercept injection (treatment group). Methods: Next-generation sequencing was performed to determine the miRNA profiles. Deregulated miRNAs were validated with quantitative real-time PCR (qRT-PCR) in another cohort. The mRNA profile data (GSE160310) of PDR patients were retrieved from the Gene Expression Omnibus (GEO) database. The function of differentially expressed miRNAs and mRNAs was annotated by bioinformatic analysis and literature study. Results: Twenty-nine miRNAs were significantly dysregulated in the three groups, of which 19,984 target mRNAs were predicted. Hsa-miR-3184-3p, hsa-miR-24-3p, and hsa-miR-197-3p were validated to be remarkably upregulated in no-treatment group versus controls, and significantly downregulated in treatment group versus no-treatment group. In the GSE160310 profile, 204 deregulated protein-coding mRNAs were identified, and finally 179 overlapped mRNAs between the 19,984 target mRNAs and 204 deregulated mRNAs were included for further analysis. Function analysis provided several roles of aflibercept-induced miRNAs, promoting the alternation of drug sensitivity or resistance-related mRNAs, and regulating critical mRNAs involved in angiogenesis and retinal fibrosis. Conclusion: Hsa-miR-3184-3p, hsa-miR-24-3p, and hsa-miR-197-3p were highly expressed in PDR patients, and intravitreal aflibercept injection could reverse this alteration. Intravitreal aflibercept injection may involve in regulating cell sensitivity or resistance to drug, angiogenesis, and retinal fibrosis.

In Vitro Identification of New Transcriptomic and miRNomic Profiles Associated with Pulmonary Fibrosis Induced by High Doses Everolimus: Looking for New Pathogenetic Markers and Therapeutic Targets

The administration of Everolimus (EVE), a mTOR inhibitor used in transplantation and cancer, is often associated with adverse effects including pulmonary fibrosis. Although the underlying mechanism is not fully clarified, this condition could be in part caused by epithelial to mesenchymal transition (EMT) of airway cells. To improve our knowledge, primary bronchial epithelial cells (BE63/3) were treated with EVE (5 and 100 nM) for 24 h. EMT markers (α-SMA, vimentin, fibronectin) were measured by RT-PCR. Transepithelial resistance was measured by Millicell-ERS ohmmeter. mRNA and microRNA profiling were performed by Illumina and Agilent kit, respectively. Only high dose EVE increased EMT markers and reduced the transepithelial resistance of BE63/3. Bioinformatics showed 125 de-regulated genes that, according to enrichment analysis, were implicated in collagen synthesis/metabolism. Connective tissue growth factor (CTGF) was one of the higher up-regulated mRNA. Five nM EVE was ineffective on the pro-fibrotic machinery. Additionally, 3 miRNAs resulted hyper-expressed after 100 nM EVE and able to regulate 31 of the genes selected by the transcriptomic analysis (including CTGF). RT-PCR and western blot for MMP12 and CTGF validated high-throughput results. Our results revealed a complex biological network implicated in EVE-related pulmonary fibrosis and underlined new potential disease biomarkers and therapeutic targets.

Custom 4-Plex DiLeu Isobaric Labels Enable Relative Quantification of Urinary Proteins in Men with Lower Urinary Tract Symptoms (LUTS)

The relative quantification of proteins using liquid chromatography mass spectrometry (LC-MS) has allowed researchers to compile lists of potential disease markers. These complex quantitative workflows often include isobaric labeling of enzymatically-produced peptides to analyze their relative abundances across multiple samples in a single LC-MS run. Recent efforts by our lab have provided scientists with cost-effective alternatives to expensive commercial labels. Although the quantitative performance of these dimethyl leucine (DiLeu) labels has been reported using known ratios of complex protein and peptide standards, their potential in large-scale proteomics studies using a clinically relevant system has never been investigated. Our work rectifies this oversight by implementing 4-plex DiLeu to quantify proteins in the urine of aging human males who suffer from lower urinary tract symptoms (LUTS). Protein abundances in 25 LUTS and 15 control patients were compared, revealing that of the 836 proteins quantified, 50 were found to be differentially expressed (>20% change) and statistically significant (p-value <0.05). Gene ontology (GO) analysis of the differentiated proteins showed that many were involved in inflammatory responses and implicated in fibrosis. While confirmation of individual protein abundance changes would be required to verify protein expression, this study represents the first report using the custom isobaric label, 4-plex DiLeu, to quantify protein abundances in a clinically relevant system.

Decreased expression of Kallmann syndrome 1 sequence gene (KAL1) contributes to oral squamous cell carcinoma progression and significantly correlates with poorly differentiated grade

BACKGROUND

Kallmann syndrome 1 sequence gene (KAL1) protein is an extracellular matrix associated protein which plays vital roles in neurons development and cell migration. However, its biological functions and clinical implications have yet not been revealed in oral carcinogenesis. The objective of the study was to evaluate the role of KAL1 in oral cancer and determine clinical significance of KAL1 in oral squamous cell carcinomas (OSCCs).

METHODS

The expression pattern of KAL1 was examined in a testing cohort including OSCCs (n = 42) and paired adjacent tissues (PATs) (n = 14) by real-time PCR. The result was further validated in a validating cohort of OSCCs (n = 32). Correlation between clinicopathological parameters and KAL1 mRNA levels was analyzed by Kruskal-Wallis test. In vitro, the effects of KAL1 ablation through siRNA-mediated knockdown on the proliferation of OSCC cells were determined by CCK-8, BrdU, and colonies formation assays, respectively. In addition, cell cycle distribution was further evaluated by cytometry.

RESULTS

We observed that remarkably decreased expression of KAL1 mRNA in two independent cohorts (P = 0.0002 and P = 0.033, respectively). Furthermore, downregulated KAL1 mRNA was significantly associated with worse pathological grade (P = 0.013 and P = 0.035, respectively). Upon KAL1 silencing, the proliferation and colonies formation potentials of OSCC cells were notably promoted by accelerating G1 to M phase transition.

CONCLUSION

These data indicated that KAL1 plays a potential suppressive role on OSCC initiation and progression, and KAL1 gene may serve as an adjuvant biomarker for the identification of pathological grade.

Proteomic basis of stress responses in the gills of the pacific oyster Crassostrea gigas

The Pacific oyster Crassostrea gigas is one of the dominant sessile inhabitants of the estuarine intertidal zone, which is a physically harsh environment due to the presence of a number of stressors. Oysters have adapted to highly dynamic and stressful environments, but the molecular mechanisms underlying such stress adaptation are largely unknown. In the present study, we examined the proteomic responses in the gills of C. gigas exposed to three stressors (high temperature, low salinity, and aerial exposure) they often encounter in the field. We quantitatively compared the gill proteome profiles using iTRAQ-coupled 2-D LC-MS/MS. There were 3165 identified proteins among which 2379 proteins could be quantified. Heat shock, hyposalinity, and aerial exposure resulted in 50, 15, and 33 differentially expressed gill proteins, respectively. Venn diagram analysis revealed substantial different responses to the three stressors. Only xanthine dehydrogenase/oxidase showed a similar expression pattern across the three stress treatments, suggesting that reduction of ROS accumulation may be a conserved response to these stressors. Heat shock caused significant overexpression of molecular chaperones and production of S-adenosyl-l-methionine, indicating their crucial protective roles against protein denature. In addition, heat shock also activated immune responses, Ca(2+) binding protein expression. By contrast, hyposalinity and aerial exposure resulted in the up-regulation of 3-demethylubiquinone-9 3-methyltransferase, indicating that increase in ubiquinone synthesis may contribute to withstanding both the osmotic and desiccation stress. Strikingly, the majority of desiccation-responsive proteins, including those involved in metabolism, ion transportation, immune responses, DNA duplication, and protein synthesis, were down-regulated, indicating conservation of energy as an important strategy to cope with desiccation stress. There was a high consistency between the expression levels determined by iTRAQ and Western blotting, highlighting the high reproducibility of our proteomic approach and its great value in revealing molecular mechanisms of stress responses.