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Hypoplastic left heart syndrome (HLHS) is a rare but fatal birth defect in which the left side of the heart is underdeveloped. HLHS accounts for 2% to 4% of congenital heart anomalies. Whole genome sequencing (WGS) was conducted for a family trio consisting of a proband and his parents. A homozygous rare variant was detected in the PTPRB (Protein Tyrosine Phosphatase Receptor Type B) gene of the proband by functional annotation and co-segregation analysis. Sanger sequencing was used to confirm genotypes of the variant. The in silico prediction tools, including Mutation Taster, SpliceAI, and CADD, were used to predict the impact of the mutation. The allele frequencies across populations were compared based on multiple databases, including "1000 genomes" and "gnomAD". We used two vectors (pcMINI and pcDNA3.1) to generate a minigene construct to validate the mutational effect at the transcriptional level. Family-based WGS analyses showed that only a homozygous splice acceptor variant (NC_000012.12: g.70636068TG, NM_001109754.4: c.56-2AC, NG_029940.2: g.6373AC) at the exon-intron border of PTPRB gene associates with HLHS. This variant is also within the region with the enhancer activity based on UCSC genome annotation. Genotyping and Sanger sequencing revealed that the proband's parents are heterozygous for this variant. Evolutionary conservation analysis revealed that the site (NC_000012.12: g.70636068) is extremely conserved across species, supporting the evolutionary functional constraints of the ancestral wild type (T). In silico tools universally predicted a deleterious or disease-causing impact of the mutation from T to G. The mutation was not found in the 1000 genomes and gnomAD databases, which indicates that this mutation is very rare in most human populations. A splicing assay indicated that the mutated minigene caused aberrant splicing of mRNA, in which a 3 bp missing in the second exon resulted in the deletion of one amino acid (NP_001103224.1:p.Glu19del) compared to the normal protein of PRPTB (also the VE-PTP). Structure prediction revealed that the deletion occurred within the C-region of the signal peptide of VE-PTP, suggesting signal peptide-related defects as a potential mechanism for the HLHS cellular pathogeny. We report a rare homozygous variant with splicing error in PTPRB associated with HLHS. Previous model species studies revealed conserved functions of PTPRB in cardiovascular and heart development in mice and zebrafish. Our study is the first report to show the association between PTPRB and HLHS in humans.

Abnormal expression of protein tyrosine phosphatases (PTPs) has been reported to be a crucial cause of cancer. As a member of PTPs, protein tyrosine phosphatase receptor type O (PTPRO) has been revealed to play tumor suppressive roles in several cancers, while its roles in colorectal cancer (CRC) remains to be elucidated. Hence, we aimed to explore the roles and mechanisms of PTPRO in CRC initiation and progression.The influences of PTPRO on the growth and liver metastasis of CRC cells and the expression patterns of different lipid metabolism enzymes were evaluated in vitro and in vivo. Molecular and biological experiments were conducted to uncover the underpinning mechanisms of dysregulated de novo lipogenesis and fatty acid β-oxidation.PTPRO expression was notably downregulated in CRC liver metastasis compared to the primary cancer, and such a downregulation was associated with poor prognosis of patients with CRC. PTPRO silencing significantly promoted cell growth and liver metastasis. Compared with PTPRO wild-type mice, PTPRO-knockout mice developed more tumors and harbored larger tumor loads under treatment with azoxymethane and dextran sulfate sodium. Gene set enrichment analysis revealed that PTPRO downregulation was significantly associated with the fatty acid metabolism pathways. Blockage of fatty acid synthesis abrogated the effects of PTPRO silencing on cell growth and liver metastasis. Further experiments indicated that PTPRO silencing induced the activation of the AKT serine/threonine kinase (AKT)/mammalian target of rapamycin (mTOR) signaling axis, thus promoting de novo lipogenesis by enhancing the expression of sterol regulatory element-binding protein 1 (SREBP1) and its target lipogenic enzyme acetyl-CoA carboxylase alpha (ACC1) by activating the AKT/mTOR signaling pathway. Furthermore, PTPRO attenuation decreased the fatty acid oxidation rate by repressing the expression of peroxisome proliferator-activated receptor alpha (PPARα) and its downstream enzyme peroxisomal acyl-coenzyme A oxidase 1 (ACOX1) via activating the p38/extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) signaling pathway.PTPRO could suppress CRC development and metastasis via modulating the AKT/mTOR/SREBP1/ACC1 and MAPK/PPARα/ACOX1 pathways and reprogramming lipid metabolism.

Abstract: Protein tyrosine phosphatase receptor-type Q (PTPRQ), a member of the type III tyrosine phosphatase receptor (R3 PTPR) family, is composed of three domains, including 18 extracellular fibronectin type III (FN3) repeats, a transmembrane helix, and a cytoplasmic phosphotyrosine phosphatase (PTP) domain. PTPRQ was initially identified as a transcript upregulated in glomerular mesangial cells in a rat model of glomerulonephritis. Subsequently, studies found that PTPRQ has phosphotyrosine phosphatase and phosphatidylinositol phosphatase activities and can regulate cell proliferation, apoptosis, differentiation, and survival. Further in vivo studies showed that PTPRQ is necessary for the maturation of cochlear hair bundles and is considered a potential gene for deafness. In the recent two decades, 21 mutations in PTPRQ have been linked to autosomal recessive hearing loss (DFNB84) and autosomal dominant hearing loss (DFNA73). Recent mutations, deletions, and amplifications of PTPRQ have been observed in many types of cancers, which indicate that PTPRQ might play an essential role in the development of many cancers. In this review, we briefly describe PTPRQ structure and enzyme activity and focus on the correlation between PTPRQ and human disease. A profound understanding of PTPRQ could be helpful in the identification of new therapeutic targets to treat associated diseases.

Preeclampsia (PE) remains the leading cause of high morbidity and mortality in pregnancy. Injury of human umbilical vein endothelial cells (HUVECs) contributes to PE initiation. This study aims to analyze the molecular mechanism of PE-induced injury in HUVECs.HUVECs were cultured with serum collected from PE patients and healthy pregnant women. PE-treated HUVECs were transfected with miR-204-5p inhibitor, si-protein tyrosine phosphatase receptor J (PTPRJ), and FLI-06 (Notch signaling pathway inhibitor). Cell viability, apoptosis, migration, and angiogenesis were determined using the cell counting kit-8 method, flow cytometry, wound healing assay, tube formation assay, and ELISA. The binding relationship between miR-204-5p and PTPRJ 3'UTR sequence was verified using dual-luciferase reporter assay. The expressions of miR-204-5p, PTPRJ, Notch, and HES1 were determined using qRT-PCR and Western blot analysis.miR-204-5p levels were higher in PE serum. PE-treated HUVECs showed elevated miR-204-5p expression and apoptosis and reduced migration, angiogenesis and VEGF level. miR-204-5p inhibition alleviated HUVEC injury and upregulated PTPRJ transcription. Silencing PTPRJ partly reversed the protecting role of miR-204-5p inhibition in HUVECs. PTPRJ downregulation or FLI-06 treatment limited the expressions of Notch and HES1 and blocked the activation of the Notch signaling pathway, consequently promoting HUVEC injury.miR-204-5p inhibited PTPRJ transcription and the activation of the Notch signaling pathway, thereby enhancing HUVEC injury.

Background: Protein tyrosine phosphatase receptor type O (PTPRO) belongs to the PTP (protein tyrosine phosphatase) family and is widely expressed in parenchymal cells, such as breast and lung epithelial cells. PTPRO has been shown to enhance inflammatory responses and has been implicated in the pathogenesis of inflammation-associated diseases. The role of PTPRO in pneumonia was investigated. Methods: Human embryonic lung fibroblasts (HFL1) were treated with increasing concentrations of lipopolysaccharide at 5, 10, or 20 μg/mL to induce inflammatory and apoptotic injuries. Expression of PTPRO was detected by western blot. Inflammation and apoptosis were assessed by ELISA and flow cytometry assays, respectively. Results: Lipopolysaccharide induced decreased cell viability, and increased inflammation and apoptosis in HFL1. PTPRO was upregulated in HFL1 post lipopolysaccharide treatment, and silencing of PTPRO enhanced lipopolysaccharide-induced cell viability of HFL1, and suppressed the inflammation and apoptosis. However, overexpression of PTPRO aggravated lipopolysaccharide-induced cytotoxicity in HFL1. Overexpression of PTPRO upregulated protein expression of TLR4 and p-p65 in lipopolysaccharide-induced HFL1, while knockdown of PTPRO reduced the level of p-IκBα to downregulate levels of TLR4 and p-p65. Conclusion: PTPRO contributed to pro-inflammatory and pro-apoptotic effects on lipopolysaccharide-induced HFL1 through activation of TLR4/NF-κB signaling.

Protein tyrosine phosphatase (PTPase) is critically involved in the regulation of hematopoietic stem cell development and differentiation. Roles of novel isolated receptor PTPase PTPRO from bone marrow hematopoietic stem cells in granulopoiesis have not been investigated. PTPRO expression is correlated with granulocytic differentiation, and Ptpro−/− mice developed neutrophilia, with an expanded granulocytic compartment resulting from a cell-autonomous increase in the number of granulocyte progenitors under steady-state and potentiated innate immune responses against Listeria monocytogenes infection. Mechanistically, mTOR and HIF1α signaling engaged glucose metabolism and initiated a transcriptional program involving the lineage decision factor C/EBPα, which is critically required for the PTPRO deficiency-directed granulopoiesis. Genetic ablation of mTOR or HIF1α or perturbation of glucose metabolism suppresses progenitor expansion, neutrophilia, and higher glycolytic activities by Ptpro−/−. In addition, Ptpro−/− upregulated HIF1α regulates the lineage decision factor C/EBPα promoter activities. Thus, our findings identify a previously unrecognized interplay between receptor PTPase PTPRO signaling and mTOR-HIF1α metabolic reprogramming in progenitor cells of granulocytes that underlies granulopoiesis.

Preeclampsia (PE), a pregnancy-specific syndrome, is the primary cause of maternal mortality. This work was designed to investigate the specific functions of PTPRO/ ERp44 in the biological behaviors of trophoblast cells and elucidate the underlying molecular mechanism. Constructed siRNA-PTPRO and ERp44 overexpression plasmids were transfected into HTR-8/SVneo and JEG-3 cells for further functional experiments. Subsequently, the proliferation and invasion of trophoblast cells were identified by performing CCK-8, flow cytometry and transwell assay. In addition, tube formation assay was employed to estimate the angiogenic ability of HUVECs incubated with the conditioned media (CM) of HTR-8/SVneo or JEG-3 cells. Importantly, the interaction between PTPRO and ERp44 was analyzed through Co-IP. In the current investigation, it was discovered that downregulation of PTPRO notably facilitated the proliferation and invasion of trophoblast cells and induced a stronger in vitro angiogenesis. Moreover, PTPRO interacted with ERp44 to regulate ERp44 expression. ERp44 overexpression suppressed the proliferative, invasive and angiogenic activities of trophoblast cells. As a result, functions of PTPRO knockdown in the biological behaviors of trophoblast cells were partially abrogated upon elevation of ERp44. To sum up, this current research systematically evidenced that PTPRO could regulate the biological behaviors of trophoblast cells by modulating ERp44. Findings may contribute to a novel therapeutic strategy for PE.

Background Radiotherapy is one of the main treatments for esophageal squamous cell carcinoma (ESCC), but its efficacy is limited by radioresistance. MicroRNAs play a crucial role in posttranscriptional regulation, which is linked to the cancer response to radiation. Methods We successfully established a radioresistant cell line model by using fractionated irradiation. qRT-PCR was adopted to detect the expression of miR-4443 in human normal esophageal cell lines, tumor cells, and radioresistant cells. Next, CCK-8, colony formation, apoptosis, and cell cycle assays were used to assess the biological effect of miR-4443. Weighted gene coexpression network analysis (WGCNA) was performed to identify potential radiosensitivity-related genes. Additionally, we predicted the probable targets of the miRNA using bioinformatic methods and confirmed them using Western blot. Results miR-4443 was significantly upregulated in radioresistant ESCC cells. Enhancement of miR-4443 further decreased the radiosensitivity of ESCC cells, while inhibition of miR-4443 increased the radiosensitivity of ESCC cells. Notably, miR-4443 modulated radiosensitivity by influencing DNA damage repair, apoptosis, and G2 cycle arrest. By using WGCNA and experimental validation, we identified PTPRJ as a key target for miRNA-4443 to regulate radiosensitivity. The effects of miR-4443 overexpression or inhibition could be reversed by increasing or decreasing PTPRJ expression. Conclusion In this study, miR-4443 is found to promote radiotherapy resistance in ESCC cells by regulating PTPRJ expression, which provides a new perspective and clue to alleviate radioresistance.

Background The prognosis of hepatocellular carcinoma (HCC) has been extensively studied. However, the impact on prognosis of stage I HCC has not been well studied at clincopathological, mutational and transcriptional levels. Methods Here we first characterized the influencing factors of prognosis of stage I HCC patients by downloading and analyzing the whole-exome somatic mutation data, messenger ribonucleic acid (mRNA) transcription data, along with demographic and clinical information of 163 stage I HCC patients from the TCGA database. The relationship between the influencing factors and HCC prognosis was studied in detail, and a prediction Nomogram model was established. Figures and tables were plotted using the R software. Results TP53, CTNNB1, TTN, MUC16 and ALB were the top mutated genes in stage I HCC. A series of co-mutations and mutually exclusive mutations were identified. Twenty-nine genes with significant stratification on prognosis were identified, including highly mutated LRP1B, ARID1A and PTPRQ. Patients with wild type (WT) genes unanimously exhibited significantly better overall survival rate than those with mutants. Patients with the top 10% tumor mutational burden (TMB) exhibited significantly worse prognosis than the rest 90%. Further characterization of transcriptional profile revealed that membrane functions, cell skeleton proteins, ion channels, receptor function and cell cycle were comprehensively altered in stage I HCC. Univariate and multivariate analyses were performed at clinicopathological, mutational and transcriptional levels. The combined analysis revealed sex, race, TMB, neoplasm histologic grade, Child–Pugh grade, MMRN1, OXT and COX6A2 transcription as independent risk factors. These factors were used to establish a Nomogram model to predict the prognosis of individual HCC patients. Conclusions The influencing factors of prognosis of stage I HCC have been characterized for the first time at clinicopathological, mutational and transcriptional levels. A Nomogram model has been established to predict the prognosis. Further validation is needed to confirm the effectiveness and reliability of the model.

Squamous cell carcinoma of the uterine cervix (CSCC) is one of the leading causes of death in Indian women. Protein tyrosine phosphatase receptor (PTPR) type J (also known as DEP1) is a recently reported tumour suppressor receptor phosphatase. Critical molecular analysis of PTPRJ/DEP1 (11p11.2) has not performed in CSCC to date. Here, we observed frequent downregulation of cancer samples (

The inner ear is an essential part of a well-developed and well-coordinated hearing system. However, hearing loss can make communication and interaction more difficult. Inherited hearing loss (HL) can occur from pathogenic genetic variants that negatively alter the intricate inner ear sensory mechanism. Recessively inherited forms of HL are highly heterogeneous and account for a majority of prelingual deafness. The current study is designed to investigate genetic causes of HL in three consanguineous Pakistani families. After IRB approval, the clinical history and pure tone audiometric data was obtained for the clinical diagnosis of HL segregating in these three Pakistani families. We performed whole exome sequencing (WES) followed by Sanger sequencing in order to identify and validate the HL-associated pathogenic variants, respectively. The 3-D molecular modeling and the Ramachandran analysis of the identified missense variants were compiled to evaluate the impact of the variants on the encoded proteins. Clinical evaluation revealed prelingual severe to profound sensorineural HL segregating among the affected individuals in all three families. Genetic analysis revealed segregation of several novel variants associated with HL, including a canonical splice-site variant (c.55-2A>G) of PTPRQ in family GCFHL-01, a missense variant [c.1079G>A; p.(Arg360Gln)] of SERPINB6 in family LUHL-01, and an insertion variant (c.10208-10211insCCACCAGGCCCGTGCCTC) within MYO15A in family LUHL-011. All the identified variants had very low frequencies in the control databases. The molecular modeling of p.Arg360Gln missense variant also predicted impaired folding of SERPINB6 protein. This study reports the identification of novel disease-causing variants in three known deafness genes and further highlights the genetic heterogeneity of HL in Pakistani population.

Bone-resorbing osteoclasts (OCLs) are multinucleated phagocytes, whose central roles in regulating bone formation and homeostasis are critical for normal health and development. OCLs are produced from precursor monocytes in a multistage process that includes initial differentiation, cell-cell fusion, and subsequent functional and morphological maturation; the molecular regulation of osteoclastogenesis is not fully understood. Here, we identify the receptor-type protein tyrosine phosphatase PTPRJ as an essential regulator specifically of OCL maturation. Monocytes from PTPRJ-deficient (JKO) mice differentiate and fuse normally, but their maturation into functional OCLs and their ability to degrade bone are severely inhibited. In agreement, mice lacking PTPRJ throughout their bodies or only in OCLs exhibit increased bone mass due to reduced OCL-mediated bone resorption. We further show that PTPRJ promotes OCL maturation by dephosphorylating the M-CSF receptor (M-CSFR) and Cbl, thus reducing the ubiquitination and degradation of the key osteoclastogenic transcription factor NFATc1. Loss of PTPRJ increases ubiquitination of NFATc1 and reduces its amounts at later stages of osteoclastogenesis, thereby inhibiting OCL maturation. PTPRJ thus fulfills an essential and cell-autonomous role in promoting OCL maturation by balancing between the pro- and anti-osteoclastogenic activities of the M-CSFR and maintaining NFATc1 expression during late osteoclastogenesis.

Introduction The categorization of mature B cell neoplasms (MBN) infiltrating blood and bone marrow are met with difficulties. The inclusion of CD148 and CD180 in the routine flow cytometry/FCM panels has been suggested to refine the diagnosis. We studied the discriminatory ability of CD148 and CD180 median fluorescence intensity(MFI), CD148/CD180 ratio and their expression relative to T cells (CD148ab/T , CD180ab/T ), neutrophils (CD148ab/gr , CD180ab/gr ) and normal B cells (CD148ab/n , CD180ab/n ) in the differentiation of mature B cell neoplasms (MBN) especially non-chronic lymphocytic leukaemia (CLL). Methodology The flow cytometric (FCM) expression of CD148 and CD180 was studied prospectively in 102 patients (non-CLL; n = 72); diagnosed by a comprehensive panel of immunophenotypic and cytogenetic studies. The MFI and ratios were statistically compared across MBNs by Mann-Whitney U test. Cut-off values, sensitivity and specificity were calculated for significant parameters by receiver operator characteristic curve. Results CD180MFI > 4.35 showed 100% sensitivity and 90.9% specificity for a diagnosis of marginal zone lymphoma (MZL) while, CD148/180 > 5.15 was 100% specific and 81.8% sensitive for lymphoplasmacytic lymphoma. CD148ab/T (>4.3; 100% specificity, 83.4% sensitivity) and CD148ab/gr (>1.1; 100% sensitivity, 90% sensitivity) were useful for differentiating blastoid-mantle cell lymphoma/MCL from diffuse large B cell lymphoma; while CD148MFI (≥20.25), CD148ab/T (>3.35) and CD148ab/gr (>0.95) showed >90% specificity and sensitivity for distinguishing MCL from CLL. Pairwise analysis also showed a good discriminant function of various parameters for distinguishing SMZL from other MBNs like FL, MCL as well as CLL. Conclusions The current study shows an excellent utility of CD148MFI, CD180MFI, their ratio and relative expression levels in the subcategorization of immunophenotypically related MBNs.

Cervical cancer (CC) is one of the most common malignant tumors. This study analyzed the impact of protein tyrosine phosphatase, receptor type B (PTPRB) on malignant behavior of CC and explored its possible molecular mechanism. RT-PCR, western blot and Immunohistochemistry were applied to examine the expression of PTPRB in CC specimens and cells. Aberrant PTPRB expression in CC and survival outcomes were constructed using The Cancer Genome Atlas (TCGA) database and tissue microarray cervical squamous cell carcinoma cohort. Cultured human CC cells were assayed for viability, apoptosis, migration, and invasion in vitro and in vivo. Kyoto Encyclopedia of Genes and Genomes (KEGG) assays and gene set enrichment analysis (GSEA) assays were used to delve into PTPRB-related pathways using TCGA datasets. The levels of proteins associated with the epithelial–mesenchymal transition (EMT) pathway and modulated by PTPRB were examined through Western blot. We found that the levels of PTPRB in CC tissues and cells were distinctly up-regulated. PTPRB was also an unfavorable prognostic factor for CC patients. Functionally, PTPRB knockdown exhibits tumor-suppressive function via reducing cell proliferation and metastasis and inducing cell apoptosis. KEGG assays and GSEA assays suggested PTPRB overexpression was associated with several tumor-related pathways. The results of Western blot assays suggested that N-cadherin was decreased in the PTPRB-knockdown CC cells, while E-cadherin was increased. Overall, PTPRB is highly expressed in CC and can effectively enhance the proliferation, metastasis and EMT process of tumor cells. PTPRB is expected to be a therapeutic target for CC.

Poor immunogenicity and extensive immunosuppressive T-cell infiltration in the tumor immune microenvironment (TIME) have been identified as potential barriers to immunotherapy success in "immune-cold" breast cancers. Thus, it is crucial to identify biomarkers that can predict immunotherapy efficacy. Protein tyrosine phosphatase receptor type O (PTPRO) regulates multiple kinases and pathways and has been implied to play a regulatory role in immune cell infiltration in various cancers.ESTIMATE and single-sample gene set enrichment analysis (ssGSEA) were performed to uncover the TIME landscape. The correlation analysis of PTPRO and immune infiltration was performed to characterize the immune features of PTPRO. Univariate and multivariate Cox analyses were applied to determine the prognostic value of various variables and construct the PTPRO-related CD8High PTPRO expression was related to high infiltration levels of CD8PTPRO significantly impacts CD8

Receptor-type protein tyrosine phosphatases (RPTPs) receive extracellular stimuli and transfer them into cells. They regulate cell growth, differentiation and death via specific signals. They have also been implicated in cancer, diabetes and neurological diseases. RPTPH, a member of the type 3 RPTP (R3-PTP) family, is an important regulator of colorectal cancer and hepatic carcinoma. Despite its importance in drug development, the structure of RPTPH has not yet been resolved. Here, the crystal structure of the catalytic domain of RPTPH was determined at 1.56 Å resolution. Despite similarities to other R3-PTPs in its overall structure, RPTPH exhibited differences in its loop regions and side-chain conformations. Compared with other R3-PTPs, RPTPH has unique side chains near its active site that may confer specificity for inhibitor binding. Therefore, detailed information on the structure of RPTPH provides clues for the development of specific inhibitors.

Background Hemorrhage shock (HS) is characterized by decreased tissue oxygenation and organ damage due to severe blood loss. Protein tyrosine phosphatase receptor type O (PTPRO) is abnormally up-regulated in the rat lungs after trauma/HS. Methods To elucidate the regulatory mechanism of PTPRO in lung inflammation following HS, we established a rat model of HS via withdrawing blood by a catheter inserted into the femoral artery followed by resuscitation. The rats were infected with lentivirus harboring short hairpin RNA (shRNA) targeting PTPRO by intratracheal instillation. Results PTPRO was significantly up-regulated in rat lungs after HS. PTPRO knockdown enhanced epithelial integrity and reduced capillary leakage by up-regulating tight junction proteins zonula occludens-1 (ZO-1) and occludin (OCC) in the lungs. Besides, HS-induced myeloperoxidase activity and inflammatory cell infiltration was mitigated by PTPRO knockdown. The expression of inflammatory cytokines/chemokines (TNF-α, IL-6, MIP-2, MCP-1, and KC) in the lungs and bronchoalveolar lavage fluid was regressed after PTPRO knockdown. The nuclear factor kappa B (NF-κB) pathway was involved in HS-induced lung inflammation. PTPRO down-regulation inhibited the NF-κB pathway activation by suppressing the phosphorylation of NF-κB and its translocation from the cytoplasm into the nucleus in HS. Conclusion Taken together, we demonstrated that PTPRO knockdown may contribute to attenuating inflammation in HS-induced lung injury via inhibiting NF-κB pathway activation.

BACKGROUND: Antibody-mediated rejection (AMR) accounts for >50% of kidney allograft loss. Donor-specific antibodies (DSA) against HLA and non-HLA antigens in the glomeruli and the tubulointerstitium cause AMR while inflammatory cytokines such as TNFα trigger graft injury. The mechanisms governing cell-specific injury in AMR remain unclear. METHODS: Unbiased proteomic analysis of laser-captured and microdissected glomeruli and tubulointerstitium was performed on 30 for-cause kidney biopsy specimens with early AMR, acute cellular rejection (ACR), or acute tubular necrosis (ATN). RESULTS: A total of 107 of 2026 glomerular and 112 of 2399 tubulointerstitial proteins was significantly differentially expressed in AMR versus ACR; 112 of 2026 glomerular and 181 of 2399 tubulointerstitial proteins were significantly dysregulated in AMR versus ATN (P

Genome-wide approaches applied for the identification of new hereditary colorectal cancer (CRC) genes, identified several potential causal genes, including RPS20, IL12RB1, LIMK2, POLE2, MRE11, POT1, FAN1, WIF1, HNRNPA0, SEMA4A, FOCAD, PTPN12, LRP6, POLQ, BLM, MCM9, and the epigenetic inactivation of PTPRJ. Here we attempted to validate the association between variants in these genes and nonpolyposis CRC by performing a mutational screening of the genes and PTPRJ promoter methylation analysis in 473 familial/early-onset CRC cases, a systematic review of the published cases, and assessment of allele frequencies in control population. In the studied cohort, 24 (5%) carriers of (predicted) deleterious variants in the studied genes and no constitutional PTPRJ epimutations were identified. Assessment of allele frequencies in controls compared with familial/early-onset patients with CRC showed association with increased nonpolyposis CRC risk of disruptive variants in RPS20, IL12RB1, POLE2, MRE11 and POT1, and of FAN1 c.149T>G (p.Met50Arg). Lack of association was demonstrated for LIMK2, PTPN12, LRP6, PTPRJ, POLQ, BLM, MCM9 and FOCAD variants. Additional studies are required to provide conclusive evidence for SEMA4A, WIF1, HNRNPA0 c.-110G>C, and FOCAD large deletions.

Aims Receptor-type vascular endothelial protein tyrosine phosphatase (VE-PTP) dephosphorylates Tie-2 as well as CD31, VE-cadherin, and vascular endothelial growth factor receptor 2 (VEGFR2). The latter form a signal transduction complex that mediates the endothelial cell response to shear stress, including the activation of the endothelial nitric oxide (NO) synthase (eNOS). As VE-PTP expression is increased in diabetes, we investigated the consequences of VE-PTP inhibition (using AKB-9778) on blood pressure in diabetic patients and the role of VE-PTP in the regulation of eNOS activity and vascular reactivity. Methods and results In diabetic patients AKB-9778 significantly lowered systolic and diastolic blood pressure. This could be linked to elevated NO production, as AKB increased NO generation by cultured endothelial cells and elicited the NOS inhibitor-sensitive relaxation of endothelium-intact rings of mouse aorta. At the molecular level, VE-PTP inhibition increased the phosphorylation of eNOS on Tyr81 and Ser1177 (human sequence). The PIEZO1 activator Yoda1, which was used to mimic the response to shear stress, also increased eNOS Tyr81 phosphorylation, an effect that was enhanced by VE-PTP inhibition. Two kinases, i.e. abelson-tyrosine protein kinase (ABL)1 and Src were identified as eNOS Tyr81 kinases as their inhibition and down-regulation significantly reduced the basal and Yoda1-induced tyrosine phosphorylation and activity of eNOS. VE-PTP, on the other hand, formed a complex with eNOS in endothelial cells and directly dephosphorylated eNOS Tyr81 in vitro. Finally, phosphorylation of eNOS on Tyr80 (murine sequence) was found to be reduced in diabetic mice and diabetes-induced endothelial dysfunction (isolated aortic rings) was blunted by VE-PTP inhibition. Conclusions VE-PTP inhibition enhances eNOS activity to improve endothelial function and decrease blood pressure indirectly, through the activation of Tie-2 and the CD31/VE-cadherin/VEGFR2 complex, and directly by dephosphorylating eNOS Tyr81. VE-PTP inhibition, therefore, represents an attractive novel therapeutic option for diabetes-induced endothelial dysfunction and hypertension.

CD148 is a transmembrane protein tyrosine phosphatase (PTP) that is expressed in the renal vasculature, including the glomerulus. Previous studies have shown that CD148 plays a role in the negative regulation of growth factor signals (including epidermal growth factor and vascular endothelial growth factor), suppressing cell proliferation and transformation. However, the role of CD148 in kidney disease remains unknown. Here, we generated an agonistic anti-CD148 antibody and evaluated its effects in murine diabetic nephropathy (DN). Monoclonal antibodies (mAbs) against the mouse CD148 ectodomain sequence were generated by immunizing CD148 knockout (CD148KO) mice. The mAbs that increased CD148 activity were selected by biological (proliferation) and biochemical (PTP activity) assays. The mAb (18E1) that showed strong agonistic activity was injected (10 mg/kg ip) in streptozotocin-induced wild-type and CD148KO diabetic mice for 6 wk, and the renal phenotype was then assessed. The effects of 18E1 mAb in podocyte growth factor signals were also assessed in culture. Compared with control IgG, 18E1 mAb significantly decreased albuminuria and mesangial expansion without altering hyperglycemia and blood pressure in wild-type diabetic mice. Immunohistochemical evaluation showed that 18E1 mAb significantly prevented the reduction of podocyte number and nephrin expression and decreased glomerular fibronectin expression and renal macrophage infiltration. The 18E1 mAb showed no effects in CD148KO diabetic mice. Furthermore, we demonstrated that 18E1 mAb reduces podocyte epidermal growth factor receptor signals in culture and in diabetic mice. These findings suggest that agonistic anti-CD148 mAb attenuates DN in mice, in part by reducing epidermal growth factor receptor signals in podocytes. This antibody may be used for the treatment of early DN.

Thymic involution during aging is a major cause of decreased T-cell production and reduced immunity. Here, we show that the loss of CD147 on T cells prevents thymic senescence, resulting in slowed shrinkage of the thymus with age and increased production of naive T cells. This phenotype is the result of slowing of the epithelial–mesenchymal transition (EMT) process in thymic epithelial cells (TECs), which eventually leads to reduced adipocyte accumulation. In an in vitro coculture system, we found that TGFβ is an important factor in the EMT process in TECs and that it can reduce the expression of E-cadherin through p-Smad2/FoxC2 signaling. Moreover, CD147 on T cells can accelerate the decline in E-cadherin expression by interacting with Annexin A2 on TECs. In the presence of TGFβ, Annexin A2 and E-cadherin colocalize on TECs. However, CD147 on T cells competitively binds to Annexin A2 on TECs, leading to the isolation of E-cadherin. Then, the isolated E-cadherin is easily phosphorylated by phosphorylated Src kinase, the phosphorylation of which was induced by TGFβ, and finally, p-E-cadherin is degraded. Thus, in the thymus, the interaction between T cells and TECs contributes to thymic involution with age. In this study, we illuminate the mechanism underlying the triggering of the EMT process in TECs and show that inhibiting TGFβ and/or CD147 may serve as a strategy to hinder age-related thymic involution.

Background Laboratories utilizing next-generation sequencing align sequence data to a standardized human reference genome (HRG). Several updated versions, or builds, have been released since the original HRG in 2001, including the Genome Reference Consortium Human Build 38 (GRCh38) in 2013. However, most clinical laboratories still use GRCh37, which was released in 2009. We report our laboratory’s clinical validation of GRCh38. Methods Migration to GRCh38 was validated by comparing the coordinates (lifting over) of 9443 internally curated variants from GRCh37 to GRCh38, globally comparing protein coding sequence variants aligned with GRCh37 vs GRCh38 from 917 exomes, assessing genes with known discrepancies, comparing coverage differences, and establishing the analytic sensitivity and specificity of variant detection using Genome in a Bottle data. Results Eight discrepancies, due to strand swap or reference base, were observed. Three clinically relevant variants had the GRCh37 alternate allele as the reference allele in GRCh38. A comparison of 88 295 calls between builds identified 8 disease-associated genes with sequence differences: ABO, BNC2, KIZ, NEFL, NR2E3, PTPRQ, SHANK2, and SRD5A2. Discrepancies in coding regions in GRCh37 were resolved in GRCh38. Conclusions There were a small number of clinically significant changes between the 2 genome builds. GRCh38 provided improved detection of nucleotide changes due to the resolution of discrepancies present in GRCh37. Implementation of GRCh38 results in more accurate and consistent reporting.

Up to now, no study focused on the role of SdrG in PJI after THA. To explore the mechanism of periprosthetic joint infection (PJI) after total hip arthroplasty (THA).Joint fluid and blood were collected from patients with PJI after THA, aseptic loosening of the joints or bacterial infection after traumatic fractures of the extremities alone. The expression of SdrG in the 3 groups was determined by agarose gel electrophoresis. The expression of protein tyrosine phosphatase receptor J (PTPRJ) was measured by immunohistochemistry method. The platelet adhesion rate was determined by biochemical analysis. The content of D-dimer, CRP and ESR in blood was determined by latex agglutination method. Multiple linear correlation analysis was used to analyse the correlation between PJI and the expression of PTPRJ protein, platelet adhesion rate, D-dimer content, CRP and ESR.The expression of SdrG and PTPRJ in PJI group was markedly increased compared to the other 2 groups. The platelet adhesion rate in PJI group was markedly larger compared to aseptic loosening and simple wound infection group, and the rate in simple wound infection group was larger than aseptic loosening group. The level of D-dimer, CRP and ESR in PJI group was higher than that of the other groups. The expression of PTPRJ protein, D-dimer content, CRP and ESR was all closely related to PJI, while platelet adhesion rate had no correlation with PJI.SDRG gene around joint prosthesis was over-expressed, which activated joint surface membrane protein PTPRJ and then induced platelet aggregation to reduce joint function.

The members of the protein tyrosine phosphatase (PTP) family are key regulators in multiple signal transduction pathways and therefore they play important roles in many cellular processes, including immune response. As a member of PTP family, protein tyrosine phosphatase receptor type O (PTPRO) belongs to the R3 receptor-like protein tyrosine phosphatases. The expression of PTPRO isoforms is tissue-specific and the truncated PTPRO (PTPROt) is mainly observed in hematopoietic cells, including B cells, T cells, macrophages and other immune cells. Therefore, PTPROt may play an important role in immune cells by affecting their growth, differentiation, activation and immune responses. In this review, we will focus on the regulatory roles and underlying molecular mechanisms of PTPRO/PTPROt in immune cells, including B cells, T cells, and macrophages.

Previously, a case series study was conducted on our part in which 5 patients with Graves' disease (GD) were collected from a 3-generation family to screen for susceptibility genes responsible for GD. The single nucleotide variants of Microtubule-associated protein 7 domain containing 2 c. 452C T, p. Ala151Val, Solute carrier family 1 member 7 c. 1204C T, p. Arg402Cys, tumor necrosis factor receptor-associated factor 3 interacting protein 3 (TRAF3IP3) c. 209A T, p. Asn70Ile, protein tyrosine phosphatase receptor type B (PTPRB) c. 3472A G, p. Ser1158Gly, Phosphoinositide-3-kinase regulatory subunit 3 c. 121C T, p. Pro41Ser, disrupted in schizophrenia 1 (DISC1), c. 1591G C p. Gly531Arg were associated with the familial GD. We then further confirmed these variants and investigated whether other mutations render susceptibility to GD. The case-control study collected patients with sporadic GD or no GD family history. A snapshot program was used for genotyping the selected SNPs in 235 GD patients (GD group 1) and 284 healthy patients (control group). Furthermore, another 184 GD patients were recruited (GD group 2) to sequence the specified exons of these genes. The sequenced data was compared with Chinese Millionome Database (CMDB). Several variants of PTPRB, phosphoinositide-3-kinase regulatory subunit 3, TRAF3IP3, and DISC1 were found in GD group 2 but not in CMDB. Moreover, the allele frequency of SNP rs2076150 (TRAF3IP3) and rs2492367 DISC1 in GD group 2 was significantly higher than that of in CMDB (all P.05). When the control group or CMDB was set as a reference group, a significantly higher frequency in alter allele C of SNP rs186466118 PTPRB was observed in GD group 1 and GD group (constituted by GD group 1 and GD group 2). Equally importantly, there was a correlation between the allele C of SNP rs186466118 and the increased risk of GD susceptibility (all P.05). PTPRB, TRAF3IP3, and DISC1 may be susceptibility genes for GD, and more variants of PTPRB, TRAF3IP3, and DISC1 were found in GD patients.

The role of EGFR in lung cancer is well described with numerous activating mutations that result in phosphorylation and tyrosine kinase inhibitors that target EGFR. While the role of the EGFR kinase in non-small cell lung cancer (NSCLC) is appreciated, control of EGFR signaling pathways through dephosphorylation by phosphatases is not as clear. Through whole genome sequencing we have uncovered conserved V483M Ptprh mutations in PyMT induced tumors. Profiling the downstream events of Ptprh mutant tumors revealed AKT activation, suggesting a key target of PTPRH was EGFR tyrosine 1197. Given the role of EGFR in lung cancer, we explored TCGA data which revealed that a subset of PTPRH mutant tumors shared gene expression profiles with EGFR mutant tumors, but that EGFR mutations and PTPRH mutations were mutually exclusive. Generation of a PTPRH knockout NSCLC cell line resulted in Y1197 phosphorylation of EGFR, and a rescue with expression of wild type PTPRH returned EGFR phosphorylation to parental line values while rescue with catalytically dead PTPRH did not. A dose response curve illustrated that two human NSCLC lines with naturally occurring PTPRH mutations responded to EGFR tyrosine kinase inhibition. Osimertinib treatment of these tumors resulted in a reduction of tumor volume relative to vehicle controls. PTPRH mutation resulted in nuclear pEGFR as seen in immunohistochemistry, suggesting that there may also be a role for EGFR as a transcriptional co-factor. Together these data suggest mutations in PTPRH in NSCLC is inhibitory to PTPRH function, resulting in aberrant EGFR activity and ultimately may result in clinically actionable alterations using existing therapies.

Carcinoembryonic Antigen-related Cell Adhesion Molecule 3 (CEACAM3) is a human granulocyte receptor mediating the efficient phagocytosis of a subset of human-restricted bacterial pathogens. Its function depends on phosphorylation of a tyrosine-based sequence motif, but the enzyme(s) responsible for reversing this modification are unclear. Here, we identify the receptor-type protein tyrosine phosphatase PTPRJ as a negative regulator of CEACAM3-mediated phagocytosis. We show depletion of PTPRJ results in a gain-of-function phenotype, while overexpression of a constitutively active PTPRJ phosphatase strongly reduces bacterial uptake via CEACAM3. We also determined that recombinant PTPRJ directly dephosphorylates the cytoplasmic tyrosine residues of purified full-length CEACAM3 and recognizes synthetic CEACAM3-derived phospho-peptides as substrates. Dephosphorylation of CEACAM3 by PTPRJ is also observed in intact cells, thereby limiting receptor-initiated cytoskeletal re-arrangements, lamellipodia formation, and bacterial uptake. Finally, we show that human phagocytes deficient for PTPRJ exhibit exaggerated lamellipodia formation and enhanced opsonin-independent phagocytosis of CEACAM3-binding bacteria. Taken together, our results highlight PTPRJ as a bona fide negative regulator of CEACAM3-initiated phagocyte functions, revealing a potential molecular target to limit CEACAM3-driven inflammatory responses. published

BACKGROUND CD148 is a transmembrane protein tyrosine phosphatase that is expressed in multiple cell types. Previous studies have shown that CD148 dephosphorylates growth factor receptors and their signaling molecules, including EGFR and ERK1/2, and negatively regulates cancer cell growth. Furthermore, research of clinical patients has shown that highly linked CD148 gene polymorphisms, Gln276Pro (Q276P) and Arg326Gln (R326Q), are associated with an increased risk of several types of cancer. However, the biological effects of these missense mutations have not been studied. AIM We aimed to determine the biological effects of CD148 Q276P/R326Q mutations in cancer cell proliferation and growth factor signaling, with emphasis on EGFR signaling. METHODS CD148 forms, wild-type (WT) or Q276P/R326Q, were retrovirally introduced into A431D epidermoid carcinoma cells that lacks CD148 expression. The stable cells that express comparable levels of CD148 were sorted by flow cytometry. A431D cells infected with empty retrovirus was used as a control. CD148 localization, cell proliferation rate, EGFR signaling, and the response to thrombospondin-1 (TSP1), a CD148 ligand, were assessed by immunostaining, cell proliferation assay, enzyme-linked immunosorbent assay, and Western blotting. RESULTS Both CD148 forms (WT, Q276P/R326Q) were distributed to cell surface and all three cell lines expressed same level of EGFR. Compared to control cells, the A431D cells that express CD148 forms showed significantly lower cell proliferation rates. EGF-induced EGFR and ERK1/2 phosphorylation as well as cell proliferation were also significantly reduced in these cells. Furthermore, TSP1 inhibited cell proliferation in CD148 (WT, Q276P/R326Q)-expressing A431D cells, while it showed no effects in control cells. However, significant differences were not observed between CD148 WT and Q276P/R326Q cells. CONCLUSION Our data demonstrates that Q276P/R326Q mutations do not have major effects on TSP1-CD148 interaction as well as on CD148's cellular localization and activity to inhibit EGFR signaling and cell proliferation.

Nephrotic syndrome appears as a group of symptoms like proteinuria, edema and hyperlipidemia. Identification of monogenic forms revealed the physiology and pathogenesis of the SRNS. We performed Illumina panel sequencing of seven genes in 90 Indian patients to determine the role of these genetic mutations in nephrotic syndrome prognosis. Samtool was used for variants calling, and SnpEff and Snpsift did variants annotation. Clinical significance and variant classification were performed by the ClinVar database. In SSNS and SRNS patients, we found 0.78% pathogenic and 3.41% likely pathogenic mutations. Pathogenic mutations were found in LAMB2, LMX1B and WT1 genes, while likely pathogenic mutations were found in (6/13) LAMB2, (2/13) LMX1B, (2/13) TRPC6, (2/13) PTPRO and (1/13) PMM2 genes. Approximately 46% likely pathogenic mutations were contributed to the LAMB2 gene in SSNS and SRNS patients. We also detect 30 VUS (variants of uncertain significance), which were found (17/30) pathogenic and (13/30) likely pathogenic by different prediction tools. Multigene panels were used for genetic screening of heterogeneous disorders like nephrotic syndrome in the Indian population. We found pathogenic, likely pathogenic and certain VUS, which were responsible for the pathogenesis of the disease. Therefore, mutational analysis of SSNS and SRNS is necessary to avoid adverse effects of corticosteroids, modify the intensity of immunosuppressing agents, and prevent the disease’s progression.

To investigate the importance of rare variants in adult-onset hearing loss.Genomic association study.Large biobank from tertiary care center.We investigated rare variants (minor allele frequency5%) in 42 autosomal dominant (DFNA) postlingual hearing loss (HL) genes in 16,657 unselected individuals in the Penn Medicine Biobank. We determined the prevalence of known pathogenic and predicted deleterious variants in subjects with audiometric-proven sensorineural hearing loss. We scanned across known postlingual DFNA HL genes to determine those most significantly contributing to the phenotype. We replicated findings in an independent cohort (UK Biobank).While rare individually, when considering the accumulation of variants in all postlingual DFNA genes, more than 90% of participants carried at least 1 rare variant. Rare variants predicted to be deleterious were enriched in adults with audiometric-proven hearing loss (pure-tone average25 dB;Although prior reports have focused on common variants, we find that rare predicted deleterious variants in DFNA postlingual HL genes are enriched in patients with adult-onset HL in a large health care system population. We show the value of investigating rare variants to uncover hearing loss phenotypes related to implicated genes.

The study was conducted between 2018 and 2020. From a cohort of 113 hearing impaired (HI), five non-DFNB12 probands identified with heterozygous CDH23 variants were subjected to exome analysis. This resolved the etiology of hearing loss (HL) in four South Indian assortative mating families. Six variants, including three novel ones, were identified in four genes: PNPT1 p.(Ala46Gly) and p.(Asn540Ser), MYO15A p.(Leu1485Pro) and p.(Tyr1891Ter), PTPRQ p.(Gln1336Ter), and SLC12A2 p.(Pro988Ser). Compound heterozygous PNPT1 variants were associated with DFNB70 causing prelingual profound sensorineural hearing loss (SNHL), vestibular dysfunction, and unilateral progressive vision loss in one family. In the second family, MYO15A variants in the myosin motor domain, including a novel variant, causing DFNB3, were found to be associated with prelingual profound SNHL. A novel PTPRQ variant was associated with postlingual progressive sensorineural/mixed HL and vestibular dysfunction in the third family with DFNB84A. In the fourth family, the SLC12A2 novel variant was found to segregate with severe-to-profound HL causing DFNA78, across three generations. Our results suggest a high level of allelic, genotypic, and phenotypic heterogeneity of HL in these families. This study is the first to report the association of PNPT1, PTPRQ, and SLC12A2 variants with HL in the Indian population.

Rheumatoid arthritis (RA)-associated interstitial lung disease (RA-ILD) is the most common pulmonary complication of RA, increasing morbidity and mortality. Anti-citrullinated protein antibodies have been associated with the development and progression of both RA and fibrotic lung disease; however, the role of protein citrullination in RA-ILD remains unclear. Here, we demonstrate that the expression of peptidylarginine deiminase 2 (PAD2), an enzyme that catalyzes protein citrullination, is increased in lung homogenates from subjects with RA-ILD and their lung fibroblasts. Chemical inhibition or genetic knockdown of PAD2 in RA-ILD fibroblasts attenuated their activation, marked by decreased myofibroblast differentiation, gel contraction, and extracellular matrix gene expression. Treatment of RA-ILD fibroblasts with the proteoglycan syndecan-2 (SDC2) yielded similar antifibrotic effects through regulation of PAD2 expression, phosphoinositide 3-kinase/Akt signaling, and Sp1 activation in a CD148-dependent manner. Furthermore, SDC2-transgenic mice exposed to bleomycin-induced lung injury in an inflammatory arthritis model expressed lower levels of PAD2 and were protected from the development of pulmonary fibrosis. Together, our results support a SDC2-sensitive profibrotic role for PAD2 in RA-ILD fibroblasts and identify PAD2 as a promising therapeutic target of RA-ILD.

The Dll4-Notch-signaling pathway regulates capillary sprouting via the specification of endothelial tip cells. While VEGF is a potent inducer of Dll4 expression, the intracellular mediators that stimulate its expression remain poorly defined. The protein tyrosine phosphatase PTPRJ/DEP-1 is required for angiogenesis in normal or pathological contexts through its modulation of VEGF signaling. Here, we show that in DEP-1 KO mice, retinas at post-natal day 5 show enlarged blood vessels, as well as an increased number of tip cells and vessel branching points at the migrating front of the vascular plexus. Consistent with these observations, the proliferation of endothelial cells is increased in the retinas of DEP-1 KO mice, as revealed by phospho-histone H3 staining, and increased phosphorylation of ERK1/2 in HUVECs transfected with DEP-1 siRNA. The expression of Dll4 was decreased in retinas of DEP-1 KO mice and was associated with decreased Notch activation. Mechanistically, reduced Dll4 expression in the absence of DEP-1 was correlated with the inhibition of the Src/Akt/β-Catenin-signaling pathway in HUVECs. Conversely, overexpression of WT DEP-1 in cultured endothelial cells, but not of mutants unable to activate Src-dependent signaling, promoted Dll4 expression. Inhibition of Src, Akt, and β-catenin transcriptional activity, leading to the inhibition of Dll4 expression, further suggested that their activation through a DEP-1-dependent pathway was required to promote Dll4 expression in VEGF-stimulated endothelial cells. Altogether, these data demonstrate that DEP-1, via Akt and β-catenin, is a significant promoter of the VEGF-induced Dll4-Notch pathway, and can contribute to the regulation of the tip and stalk cell phenotypes of endothelial cells.

Vascular endothelial protein tyrosine phosphatase (VE-PTP, PTPRB) is a receptor type phosphatase that is crucial for the regulation of endothelial junctions and blood vessel development. We and others have shown recently that VE-PTP regulates vascular integrity by dephosphorylating substrates that are key players in endothelial junction stability, such as the angiopoietin receptor TIE2, the endothelial adherens junction protein VE-cadherin and the vascular endothelial growth factor receptor VEGFR2. Here, we have systematically searched for novel substrates of VE-PTP in endothelial cells by utilizing two approaches. First, we studied changes in the endothelial phosphoproteome on exposing cells to a highly VE-PTP-specific phosphatase inhibitor followed by affinity isolation and mass-spectrometric analysis of phosphorylated proteins by phosphotyrosine-specific antibodies. Second, we used a substrate trapping mutant of VE-PTP to pull down phosphorylated substrates in combination with SILAC-based quantitative mass spectrometry measurements. We identified a set of substrate candidates of VE-PTP, of which a remarkably large fraction (29%) is related to cell junctions. Several of those were found in both screens and displayed very high connectivity in predicted functional interaction networks. The receptor protein tyrosine kinase EPHB4 was the most prominently phosphorylated protein on VE-PTP inhibition among those VE-PTP targets that were identified by both proteomic approaches. Further analysis revealed that EPHB4 forms a ternary complex with VE-PTP and TIE2 in endothelial cells. VE-PTP controls the phosphorylation of each of these two tyrosine kinase receptors. Despite their simultaneous presence in a ternary complex, stimulating each of the receptors with their own specific ligand did not cross-activate the respective partner receptor. Our systematic approach has led to the identification of novel substrates of VE-PTP, of which many are relevant for the control of cellular junctions further promoting the importance of VE-PTP as a key player of junctional signaling.

Brown adipocytes have an important role in the regulation of energy balance through uncoupling protein-1 (UCP-1)-mediated nonshivering thermogenesis. Although brown adipocytes have been highlighted as a new therapeutic target for the treatment of metabolic diseases, such as obesity and type II diabetes in adult humans, the molecular mechanism underlying brown adipogenesis is not fully understood. We recently found that protein tyrosine phosphatase receptor type B (PTPRB) expression dramatically decreased during brown adipogenic differentiation. In this study, we investigated the functional roles of PTPRB and its regulatory mechanism during brown adipocyte differentiation. Ectopic expression of PTPRB led to a reduced brown adipocyte differentiation by suppressing the tyrosine phosphorylation of VEGFR2, whereas a catalytic inactive PTPRB mutant showed no effects on differentiation and phosphorylation. Consistently, the expression of brown adipocyte-related genes, such as UCP-1, PGC-1α, PRDM16, PPAR-γ, and CIDEA, were significantly inhibited by PTPRB overexpression. Overall, these results suggest that PTPRB functions as a negative regulator of brown adipocyte differentiation through its phosphatase activity-dependent mechanism and may be used as a target protein for the regulation of obesity and type II diabetes.

Maintaining the proper balance between osteoblast-mediated production of bone and its degradation by osteoclasts is essential for health. Osteoclasts are giant phagocytic cells that are formed by fusion of monocyte-macrophage precursor cells; mature osteoclasts adhere to bone tightly and secrete protons and proteases that degrade its matrix. Phosphorylation of tyrosine residues in proteins, which is regulated by the biochemically-antagonistic activities of protein tyrosine kinases and protein tyrosine phosphatases (PTPs), is central in regulating the production of osteoclasts and their bone-resorbing activity. Here we review the roles of individual PTPs of the classical and dual-specificity sub-families that are known to support these processes (SHP2, cyt-PTPe, PTPRO, PTP-PEST, CD45) or to inhibit them (SHP1, PTEN, MKP1). Characterizing the functions of PTPs in osteoclasts is essential for complete molecular level understanding of bone resorption and for designing novel therapeutic approaches for treating bone disease.

Mucosal melanoma is a rare and poorly characterized subtype of human melanoma. Here we perform a cross-species analysis by sequencing tumor-germline pairs from 46 primary human muscosal, 65 primary canine oral and 28 primary equine melanoma cases from mucosal sites. Analysis of these data reveals recurrently mutated driver genes shared between species such as NRAS, FAT4, PTPRJ, TP53 and PTEN, and pathogenic germline alleles of BRCA1, BRCA2 and TP53. We identify a UV mutation signature in a small number of samples, including human cases from the lip and nasal mucosa. A cross-species comparative analysis of recurrent copy number alterations identifies several candidate drivers including MDM2, B2M, KNSTRN and BUB1B. Comparison of somatic mutations in recurrences and metastases to those in the primary tumor suggests pervasive intra-tumor heterogeneity. Collectively, these studies suggest a convergence of some genetic changes in mucosal melanomas between species but also distinctly different paths to tumorigenesis., Mucosal melanoma is a rare melanoma subtype that is poorly characterised. Here, the authors sequenced human, canine, and equine melanoma samples and performed a cross-species analysis, which revealed candidate driver genes, recurrent copy number alterations in regions syntenic between species, extensive intra-tumour heterogeneity and potential germline predisposing alleles

Rationale: CD148/PTRJ (receptor-like protein tyrosine phosphatase η) exerts antifibrotic effects in experimental pulmonary fibrosis via interactions with its ligand syndecan-2; however, the role of CD148 in human pulmonary fibrosis remains incompletely characterized. Objectives: We investigated the role of CD148 in the profibrotic phenotype of fibroblasts in idiopathic pulmonary fibrosis (IPF). Methods: Conditional CD148 fibroblast-specific knockout mice were generated and exposed to bleomycin and then assessed for pulmonary fibrosis. Lung fibroblasts (mouse lung and human IPF lung), and precision-cut lung slices from human patients with IPF were isolated and subjected to experimental treatments. A CD148-activating 18-aa mimetic peptide (SDC2-pep) derived from syndecan-2 was evaluated for its therapeutic potential. Measurements and Main Results: CD148 expression was downregulated in IPF lungs and fibroblasts. In human IPF lung fibroblasts, silencing of CD148 increased extracellular matrix production and resistance to apoptosis, whereas overexpression of CD148 reversed the profibrotic phenotype. CD148 fibroblast-specific knockout mice displayed increased pulmonary fibrosis after bleomycin challenge compared with control mice. CD148-deficient fibroblasts exhibited hyperactivated PI3K/Akt/mTOR signaling, reduced autophagy, and increased p62 accumulation, which induced NF-κB activation and profibrotic gene expression. SDC2-pep reduced pulmonary fibrosis in vivo and inhibited IPF-derived fibroblast activation. In precision-cut lung slices from patients with IPF and control patients, SDC2-pep attenuated profibrotic gene expression in IPF and normal lungs stimulated with profibrotic stimuli. Conclusions: Lung fibroblast CD148 activation reduces p62 accumulation, which exerts antifibrotic effects by inhibiting NF-κB–mediated profibrotic gene expression. Targeting the CD148 phosphatase with activating ligands such as SDC2-pep may represent a potential therapeutic strategy in IPF.

Vascular endothelial protein tyrosine phosphatase (VE-PTP) is a receptor-type PTP (RPTP), predominantly expressed in vascular endothelial cells. It regulates embryonic and tumor angiogenesis and controls vascular permeability and homeostasis in inflammation. Major substrates are the tyrosine kinase receptor Tie-2 and the adhesion molecule VE-cadherin. This review describes how VE-PTP controls vascular functions by its various substrates and the therapeutic potential of VE-PTP in various pathophysiological settings.

Objective. The aim of the study is to explore the prognosis value of PTPRH in patients with lung adenocarcinoma (LUAD). Methods. Oncomine, UALCAN, and GEPIA databases were employed to examine the differential expression of PTPRH between LUAD and adjacent tissues. 100 pairs of LUAD and adjacent tissue samples were involved in this study. qRT-PCR and immunohistochemical staining were performed. Meanwhile, we analyzed The Cancer Genome Atlas (TCGA) data to investigate the correlation between PTPRH gene expression and clinicopathological characteristics. Kaplan-Meier analysis and univariate and multivariate Cox analyses were performed to estimate the relationship between PTPRH expression and LUAD prognosis. The evaluation performance was verified by drawing a ROC curve. In addition, through GSEA, the changes of PTPRH expression were analyzed by GSEA to screen out primarily affected signaling pathway. Results. Oncomine, UALCAN, and GEPIA databases showed that the mRNA expression of PTPRH in LUAD tissues was significantly higher than that in adjacent tissues. qRT-PCR and immunohistochemical staining indicated the mRNA and protein levels of PTPRH in LUAD tissues were markedly upregulated. TCGA data showed that the expression of PTPRH was significantly correlated with T stage and disease stage. Kaplan-Meier analysis showed that the patients with high PTPRH expression had a poor prognosis. Univariate and multivariate Cox analyses exhibited that PTPRH expression could act as an independent prognostic factor for LUAD. The ROC curve showed that PTPRH combined with various clinicopathological features could effectively predict the prognosis of LUAD. Finally, GSEA indicated that changes in PTPRH expression level may affect p53, VEGF, Notch, and mTOR cancer-related signaling pathways. Conclusion. Our results demonstrated that PTPRH was highly expressed in LUAD and may be closely correlated with the poor prognosis of LUAD patients.

The role of microRNA (miRNA) in gestational diabetes mellitus has been widely investigated during the last decade. However, the altering effect of miR-6869-5p on immunity and placental microenvironment in gestational diabetes mellitus is largely unknown. In our study, the expression of miR-6869-5p was documented to be significantly decreased in placenta-derived mononuclear macrophages, which was also negatively related to PTPRO. Besides, PTPRO was negatively regulated by miR-6869-5p in placenta-derived mononuclear macrophages. In vitro, miR-6869-5p inhibited macrophage proliferation demonstrated by EdU and CCK-8 experiments. The inflammatory response in macrophages was also significantly inhibited by miR-6869-5p, which could regulate PTPRO as a target documented by luciferase reporter assay. Moreover, miR-6869-5p promoted M2 macrophage polarization and thus restrain inflammation. Accordingly, miR-6869-5p is involved in maintaining placental microenvironment balance by preventing from inflammation and inducing M2 macrophages in gestational diabetes mellitus.

Purpose Tyrosine kinase with immunoglobulin-like and EGF-like domains 2 (Tie2) activation in Schlemm's canal (SC) endothelium is required for the maintenance of IOP, making the angiopoietin/Tie2 pathway a target for new and potentially disease modifying glaucoma therapies. The goal of the present study was to examine the effects of a Tie2 activator, AKB-9778, on IOP and outflow function. Methods AKB-9778 effects on IOP was evaluated in humans, rabbits, and mice. Localization studies of vascular endothelial protein tyrosine phosphatase (VE-PTP), the target of AKB-9778 and a negative regulator of Tie2, were performed in human and mouse eyes. Mechanistic studies were carried out in mice, monitoring AKB-9778 effects on outflow facility, Tie2 phosphorylation, and filtration area of SC. Results AKB-9778 lowered IOP in patients treated subcutaneously for diabetic eye disease. In addition to efficacious, dose-dependent IOP lowering in rabbit eyes, topical ocular AKB-9778 increased Tie2 activation in SC endothelium, reduced IOP, and increased outflow facility in mouse eyes. VE-PTP was localized to SC endothelial cells in human and mouse eyes. Mechanistically, AKB-9778 increased the filtration area of SC for aqueous humor efflux in both wild type and in Tie2+/- mice. Conclusions This is the first report of IOP lowering in humans with a Tie2 activator and functional demonstration of its action in remodeling SC to increase outflow facility and lower IOP in fully developed mice. Based on these studies, a phase II clinical trial is in progress to advance topical ocular AKB-9778 as a first in class, Tie2 activator for treatment for ocular hypertension and glaucoma.

The signal peptides, present at the N-terminus of many proteins, guide the proteins into cell membranes. In some proteins, the signal peptide contains an extended N-terminal region and a recessed hydrophobic signal sequence. Previously, it was demonstrated that the N-terminally extended signal peptide of the human PTPRJ contains a cluster of arginine residues, which attenuates translation. The analysis of the orthologous sequences revealed that this sequence is highly conserved among mammals. The PTPRJ transcripts in placentals, marsupials, and monotremes encode a stretch of 10 – 14 arginine residues, positioned 11-12 codons downstream of the initiating AUG. The remarkable conservation of the repeated arginine residues in the PTPRJ signal peptides points to their key role. Further, the presence of an arginine cluster in the extended signal peptides of other proteins (E3 ubiquitin-protein ligase, NOTCH3) is noted and indicates a more general importance of this cis-acting mechanism of translational suppression.

Background Renal cell carcinoma (RCC) is a common urological cancer, and its risk correlates with environmental factors such as obesity, smoking and hypertension. Microarray technology enables analysis of the expression pattern of the whole phosphatome, members of which are involved in many cellular pathways and may act as either tumour suppressors or oncogenes in cancers. Materials and methods We analysed data for the expression level of 87 out of 107 known protein phosphatase genes included in the Hugo Gene Nomenclature Committee Website for 72 RCC tissues and paired healthy tissues obtained from the GEO Database. Results Our analysis revealed overexpression of DUSP1, DUSP4, PTP4A3, PTPRC and PTPRE genes at all examined stages of RCC. Moreover, we found overexpression of PTPN12 at stage 2, overexpression of CDKN3 at stages 3 and 4, and overexpression of DUSP10 and PTPN22 at stages 2, 3 and 4. Lower expression of DUSP9, PTPR9 and PTPRO was also observed at all stages. Conclusion Significant changes in expression patterns of protein tyrosine phosphatase genes confirm the involvement of this group in crucial carcinogenesis pathways underlying RCC. Thus, we postulate that protein tyrosine phosphatases play an important role in RCC promotion and progression, and may be considered as potential therapeutic targets.

Growing evidence suggests that aberrant microRNA (miRNA) expression contributes to hepatocellular carcinoma (HCC) development and progression. However, the potential role and mechanism of miR-665 in the progression of liver cancer remains largely unknown. Our current study showed that miR-665 expression was upregulated in HCC cells and tissues. High expression of miR-665 exhibited more severe tumor size, vascular invasion and Edmondson grading in HCC patients. Gain- or loss-of-function assays demonstrated that miR-665 promoted cell proliferation, migration, invasion, and the epithelial–mesenchymal transition (EMT) of HCC cells in vitro and in vivo. Tyrosine phosphatase receptor type B (PTPRB) was downregulated in HCC tissues, and was negatively correlated with miR-665 expression. Through western blotting and luciferase reporter assay, PTPRB was identified as a direct downstream target of miR-665. Restoration of PTPRB reverses the effects of miR-665 on HCC migration, invasion, and cell proliferation. A mechanistic study showed that PTPTRB mediated the functional role of miR-665 through regulation of the Hippo signaling pathway. In conclusion, our results suggested that miR-665 was a negative regulator of the PTPRB and could promote tumor proliferation and metastasis in HCC through decreasing Hippo signaling pathway activity, which can be a potential target for HCC treatment.