Peptidylprolyl isomerase C (Ppic) regulates invariant Natural Killer T cell (iNKT) differentiation in mice.

Peptidyl-prolyl cis-trans isomerase C (Ppic) is expressed in several bone marrow (BM) hematopoietic progenitors and in T-cell precursors. Since the expression profile of Ppic in the hematoimmune system was suggestive that it could play a role in hematopoiesis and/or T lymphocyte differentiation, we sought to test that hypothesis in vivo. Specifically, we generated a Ppic-deficient mouse model by targeting the endogenous locus by CRISPR/Cas9 and tested the requirement of Ppic in hematopoiesis. Several immune cell lineages covering BM progenitors, lymphocyte precursors, as well as mature cells at the periphery were analyzed. While most lineages were unaffected, invariant NKT (iNKT) cells were reduced in percentage and absolute cell numbers in the Ppic-deficient thymus. This affected the most mature stages in the thymus, S2 and S3, and the phenotype was maintained at the periphery. Additionally, immature transitional T1 and T2 B lymphocytes were increased in the Ppic-deficient spleen, but the phenotype was lost in mature B lymphocytes. In sum, our data show that Ppic is dispensable for myeloid cells, platelets, erythrocytes, αß, and γδ T lymphocytes in vivo in the steady state, while being involved in B- and iNKT cell differentiation.

Classical NF-κB activation impairs skeletal muscle oxidative phenotype by reducing IKK-α expression.

BACKGROUND: Loss of quadriceps muscle oxidative phenotype (OXPHEN) is an evident and debilitating feature of chronic obstructive pulmonary disease (COPD). We recently demonstrated involvement of the inflammatory classical NF-κB pathway in inflammation-induced impairments in muscle OXPHEN. The exact underlying mechanisms however are unclear. Interestingly, IκB kinase α (IKK-α: a key kinase in the alternative NF-κB pathway) was recently identified as a novel positive regulator of skeletal muscle OXPHEN. We hypothesised that inflammation-induced classical NF-κB activation contributes to loss of muscle OXPHEN in COPD by reducing IKK-α expression. METHODS: Classical NF-κB signalling was activated (molecularly or by tumour necrosis factor α: TNF-α) in cultured myotubes and the impact on muscle OXPHEN and IKK-α levels was investigated. Moreover, the alternative NF-κB pathway was modulated to investigate the impact on muscle OXPHEN in absence or presence of an inflammatory stimulus. As a proof of concept, quadriceps muscle biopsies of COPD patients and healthy controls were analysed for expression levels of IKK-α, OXPHEN markers and TNF-α. RESULTS: IKK-α knock-down in cultured myotubes decreased expression of OXPHEN markers and key OXPHEN regulators. Moreover, classical NF-κB activation (both by TNF-α and IKK-ß over-expression) reduced IKK-α levels and IKK-α over-expression prevented TNF-α-induced impairments in muscle OXPHEN. Importantly, muscle IKK-α protein abundance and OXPHEN was reduced in COPD patients compared to controls, which was more pronounced in patients with increased muscle TNF-α mRNA levels. CONCLUSION: Classical NF-κB activation impairs skeletal muscle OXPHEN by reducing IKK-α expression. TNF-α-induced reductions in muscle IKK-α may accelerate muscle OXPHEN deterioration in COPD.

Peri-conceptional obesogenic exposure induces sex-specific programming of disease susceptibilities in adult mouse offspring.

Vulnerability of the fetus upon maternal obesity can potentially occur during all developmental phases. We aimed at elaborating longer-term health outcomes of fetal overnutrition during the earliest stages of development. We utilized Naval Medical Research Institute (NMRI) mice to induce pre-conceptional and gestational obesity and followed offspring outcomes in the absence of any postnatal obesogenic influences. Male adult offspring developed overweight, insulin resistance, hyperleptinemia, hyperuricemia and hepatic steatosis; all these features were not observed in females. Instead, they showed impaired fasting glucose and a reduced fat mass and adipocyte size. Influences of the interaction of maternal diet∗sex concerned offspring genes involved in fatty liver disease, lipid droplet size regulation and fat mass expansion. These data suggest that a peri-conceptional obesogenic exposure is sufficient to shape offspring gene expression patterns and health outcomes in a sex- and organ-specific manner, indicating varying developmental vulnerabilities between sexes towards metabolic disease in response to maternal overnutrition.

PPIB/Cyclophilin B expression associates with tumor progression and unfavorable survival in patients with pulmonary adenocarcinoma.

Cyclophilin B (CypB), encoded by peptidylprolyl isomerase B (PPIB), is involved in cellular transcriptional regulation, immune responses, chemotaxis, and proliferation. Recent studies have shown that PPIB/CypB is associated with tumor progression and chemoresistance in various cancers. However, the clinicopathologic significance and mechanism of action of PPIB/CypB in non-small cell lung cancer (NSCLC) remain unclear. In this study, we used RNA in situ hybridization to examine PPIB expression in 431 NSCLC tissue microarrays consisting of 295 adenocarcinomas (ADCs) and 136 squamous cell carcinomas (SCCs). Additionally, Ki-67 expression was evaluated using immunohistochemistry. The role of PPIB/CypB was assessed in five human NSCLC cell lines. There was a significant correlation between PPIB/CypB expression and Ki-67 expression in ADC (Spearman correlation r=0.374, P<0.001) and a weak correlation in SCC (r=0.229, P=0.007). In ADCs, high PPIB expression (PPIBhigh) was associated with lymph node metastasis (P=0.023), advanced disease stage (P=0.014), disease recurrence (P=0.013), and patient mortality (P=0.015). Meanwhile, high Ki-67 expression (Ki-67high) was correlated with male sex, smoking history, high pT stage, lymph node metastasis, advanced stage, disease recurrence, and patient mortality in ADC (all P<0.001). However, there was no association between either marker or clinicopathological factors, except for old age and PPIBhigh (P=0.038) in SCC. Survival analyses revealed that the combined expression of PPIBhigh/Ki-67high was an independent prognosis factor for poor disease-free survival (HR 1.424, 95% CI 1.177-1.723, P<0.001) and overall survival (HR 1.266, 95% CI 1.036-1.548, P=0.021) in ADC, but not in SCC. Furthermore, PPIB/CypB promoted the proliferation, colony formation, and migration of NSCLC cells. We also observed the oncogenic properties of PPIB/CypB expression in human bronchial epithelial cells. In conclusion, PPIB/CypB contributes to tumor growth in NSCLC, and elevated PPIB/Ki-67 levels are linked to unfavorable survival, especially in ADC.

Neutrophil PPIF exacerbates lung ischemia-reperfusion injury after lung transplantation by promoting calcium overload-induced neutrophil extracellular traps formation.

Lung ischemia-reperfusion (I/R) injury is the main risk factor for primary graft dysfunction and patient death after lung transplantation (LTx). It is widely accepted that the main pathological mechanism of lung I/R injury are calcium overload, oxygen free radical explosion and neutrophil-mediated damage, which leading to the lack of effective treatment options. The aim of this study was to further explore the mechanisms of lung I/R injury after LTx and to provide potential therapeutic strategies. Our bioinformatics analysis revealed that the neutrophil extracellular traps (NETs) formation was closely involved in lung I/R injury after LTx, which was accompanied by up-regulation of peptidylprolyl isomerase F (PPIF) and peptidyl arginine deiminase 4 (PADI4). We further established an orthotopic LTx mouse model to simulate lung I/R injury in vivo, and found that PPIF and PADI4 inhibitors effectively reduced neutrophil infiltration, NETs formation, inflammatory response, and lung I/R injury. In the neutrophil model induced by HL-60 cell line in vitro, we found that PPIF inhibitor cyclosporin A (Cys A) better alleviated calcium overload induced inflammatory response, reactive oxygen species content and NETs formation. Further study demonstrated that interfering with neutrophil PPIF protected mitochondrial function by alleviating store-operated calcium entry (SOCE) during calcium overload and played the above positive role. On this basis, we found that the reduction of calcium content in neutrophils was accompanied by the inhibition of calcineurin (CN) and nuclear factor of activated T cells (NFAT). In conclusion, our findings suggested that neutrophil PPIF could serve as a novel biomarker and potential therapeutic target of lung I/R injury after LTx, which provided new clues for its treatment by inhibiting calcium overload-induced NETs formation.

Dissecting prostate Cancer: Single-Cell insight into Macrophage Diversity, molecular Prognosticators, and the role of Peptidylprolyl Isomerase F.

BACKGROUND: Prostate cancer remains a prominent challenge in oncology, with advanced stages showing poor prognosis. The tumor microenvironment (TME), and particularly tumor-associated macrophages (TAMs), plays a crucial role in disease progression. This study explores the single-cell transcriptomics of prostate cancer, determines macrophage heterogeneity, identifies prognostic gene markers, and assesses the role of PPIF in TAMs. METHODS: Single-cell RNA sequencing data from the GEO database (GSE176031) and transcriptome data from the TCGA were processed to characterize cell populations and identify prognostic genes in prostate cancer. Macrophage subpopulations were examined through clustering, followed by gene set scoring based on migration, activation, and proliferation. PPIF expression in macrophages was investigated using multiplex immunofluorescence staining on matched prostate cancer and adjacent non-tumoral tissues. RESULTS: The single-cell analysis identified 9,178 cells, categorized into 10 principal cell types, with macrophages constituting a significant part of the immune microenvironment. Four macrophage subgroups demonstrated distinct functional pathways: phagocytic, immune-regulatory, and proliferative. A total of 39 genes correlated with prostate cancer prognosis were identified, of which 10 carried the most significant prognostic information. Peptidylprolyl Isomerase F (PPIF) expression was significantly higher in TAMs from tumor tissue than normal tissue, indicating its potential regulatory role in the immune microenvironment. CONCLUSION: The intricate cellular architecture of the prostate cancer TME has been elucidated, with a focus on macrophage heterogeneity and functional specialization. Prognostic genes, including PPIF, were associated with survival outcomes, providing potential therapeutic targets. PPIF's prominent expression in TAMs may serve as a lever in cancer progression, warranting further investigation as a biomarker and a molecule of interest for therapeutic targeting within the prostate cancer milieu.

Knockdown of lncRNA JPX suppresses IL-1ß-stimulated injury in chondrocytes through modulating an miR-25-3p/PPID axis.

The aim of this study was to investigate the potential mechanisms of long noncoding (lnc) RNA Just proximal to X-inactive specific transcript (JPX) in interleukin (IL)-1ß-stimulated chondrocytes. Human C28/I2 chondrocytes were treated with IL-1ß to simulate osteoarthritic (OA) injury. The expression levels of JPX, microRNA (miRNA/miR)-25-3p, and peptidylprolyl isomerase D (PPID) were measured using reverse transcription-quantitative PCR or western blotting. The IL-1ß-stimulated injury was assessed using a Cell Counting Kit-8 assay, flow cytometry, and western blot analysis. The targeted relationship between miR-25-3p, JPX, and PPID was verified using a dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. The results showed that JPX expression was upregulated in OA patients and IL-1ß-stimulated chondrocytes. JPX knockdown enhanced cell viability and suppressed apoptosis of IL-1ß-stimulated chondrocytes. miR-25-3p inhibition rescued the inhibitory effect of JPX knockdown on IL-1ß-stimulated injury. PPID overexpression eliminated the effects of JPX knockdown on IL-1ß-stimulated chondrocytes. In conclusion, JPX knockdown increased cell viability and reduced apoptosis in IL-1ß-stimulated chondrocytes, and this involved modulation of a miR-25-3p/PPID axis.

Safety of using cultured cells with trisomy 7 in cell therapy for treating osteoarthritis.

Cell therapy is a promising alternative treatment approach currently under study for osteoarthritis (OA), the most common chronic musculoskeletal disease. However, the mesenchymal stem cells (MSCs) used in cell therapy to treat OA are usually expanded in vitro to obtain sufficient numbers for transplantation, and their safety has not been fully assessed from multiple perspectives. Analysis of karyotypic abnormalities, in particular, is important to ensure the safety of cells; however, chromosomal mutations may also occur during the cell-expansion process. In addition, there have been many reports showing chromosome abnormalities, mainly trisomy 7, in the cartilage and synovium of patients with OA as well as in normal tissues. The suitability of cells with these karyotypic abnormalities as cells for cell therapy has not been evaluated. Recently, we assessed the safety of using cells with trisomy 7 from the osteoarthritic joint of a patient for transplantation, and we followed up with the patient for 5 years. This study showed analysis for copy number variant and whole-genome sequencing, compared with blood DNA from the same patient. We did not find any abnormalities in the genes regardless of trisomy 7. No side effects were observed for at least 5 years in the human clinical study. This suggests that the transplantation of cultured cells with trisomy 7 isolated from an osteoarthritic joint and transplanted into the osteoarthritic joints of the same person is not expected to cause serious adverse events. However, it is unclear what problems may arise in the case of allogeneic transplantation. Different types of risks will also exist depending on other transplantation routes, such as localization to the knee-joint only or circulation inflow and lung entrapment. In addition, since the cause of trisomy 7 occurrence remains unclear, it is necessary to clarify the mechanism of trisomy 7 in OA to perform cell therapy for OA patients in a safe manner.

An investigation into nicotinic receptor involvement in mood disorders uncovers novel depression candidate genes.

BACKGROUND: We have previously reported reduced expression of the cholinergic autoreceptor CHRM2 in Brodmann's Area (BA) 24 of the anterior cingulate cortex from subjects with major depressive disorder (MDD) and bipolar disorder (BD), consistent with a hypercholinergic state. This led us to investigate whether levels of the high affinity nicotinic acetylcholine receptors are also altered in BA 24. METHODS: We measured the binding levels of a high-affinity nicotinic receptor-selective radioligand, [3H]epibatidine, in BA 24 from subjects with MDD (n = 20), BD (n = 18) and age- and sex-matched controls (n = 20). We used qPCR to measure mRNA expression of the high affinity nicotinic acetylcholine receptor subunit CHRNB2 in these subjects. RESULTS: [3H]Epibatidine binding density and CHRNB2 mRNA expression were not significantly altered in either MDD or BD compared to control levels. While validating reference genes for our qPCR experiments, we found that the mRNA levels of 3 putative reference genes, TFB1M, PPIA and SNCA, were increased in MDD but not BD compared to controls. Further investigations in other cortical regions showed that these changes were specific to BA24. LIMITATIONS: Cohort size and available patient data were limited due to standard constraints associated with post-mortem studies. CONCLUSION: Our data suggest that decreased CHRM2 in BA24 in mood disorders is not associated with a corresponding change in high affinity nicotinic acetylcholine receptor expression. Our findings of increased TFB1M, PPIA and SNCA expression in MDD point to a broader derangement of several homeostatic pathways in MDD that are distinct from BD.

Cardiorenal Tissues Express SARS-CoV-2 Entry Genes and Basigin (BSG/CD147) Increases With Age in Endothelial Cells.

Vascular and cardiovascular inflammation and thrombosis occur in patients with severe coronavirus disease-2019 (COVID-19). Advancing age is the most significant risk factor for severe COVID-19. Using transcriptomic databases, the authors found that: 1) cardiovascular tissues and endothelial cells express putative genes for severe acute respiratory syndrome coronavirus-2 infection, including angiotensin-converting enzyme 2 (ACE2) and basigin (BSG); 2) severe acute respiratory syndrome coronavirus-2 receptor pathways ACE2/transmembrane serine protease 2 and BSG/peptidylprolyl isomerase B(A) polarize to lung/epithelium and vessel/endothelium, respectively; 3) expression of host genes is relatively stable with age; and 4) notable exceptions are ACE2, which decreases with age in some tissues, and BSG, which increases with age in endothelial cells, suggesting that BSG expression in the vasculature may explain the heightened risk for severe disease with age.

ALCAM (CD166) as a gene expression marker for human mesenchymal stromal cell characterisation.

BACKGROUND: Human mesenchymal stromal cells (MSCs) phenotypically share their positive expression of the International Society for Cell and Gene Therapy (ISCT) markers CD73, CD90 and CD105 with fibroblasts. Fibroblasts are often co-isolated as an unwanted by-product from biopsy and they can rapidly overgrow the MSCs in culture. Indeed, many other surface markers have been proposed, though no unique MSC specific marker has been identified yet. Quantitative PCR (qPCR) is a precise, efficient and rapid method for gene expression analysis. To identify a marker suitable for accurate MSC characterisation, qPCR was exploited. METHODS AND RESULTS: Two commercially obtained bone marrow (BM) derived MSCs and an hTERT immortalised BM-MSC line (MSC-TERT) have been cultured for different days and at different oxygen levels before RNA extraction. Together with RNA samples previous extracted from umbilical cord derived MSCs and MSC-TERT cells cultured in 2D or 3D, this heterogeneous sample set was quantitatively analysed for the expression levels of 18 candidate MSC marker genes. The expression levels in MSCs were compared with the expression levels in fibroblasts to verify the differentiation capability of these genes between MSCs and fibroblasts. None of the ISCT markers could differentiate between fibroblasts and MSCs. A total of six other genes (ALCAM, CLIC1, EDIL3, EPHA2, NECTIN2, and TMEM47) were identified as possible biomarkers for accurate identification of MSCs. CONCLUSION: Justified by considerations on expression level, reliability and specificity, Activated-Leukocyte Cell Adhesion Molecule (ALCAM) was the best candidate for improving the biomarker set of MSC identification.

Dual-Family Peptidylprolyl Isomerases (Immunophilins) of Select Monocellular Organisms.

The dual-family peptidylprolyl cis-trans isomerases (immunophilins) represent a naturally occurring chimera of the classical FK506-binding protein (FKBP) and cyclophilin (CYN), connected by a flexible linker. They are found exclusively in monocellular organisms. The modular builds of these molecules represent two distinct types: CYN-(linker)-FKBP and FKBP-3TPR (tetratricopeptide repeat)-CYN. Abbreviated respectively as CFBP and FCBP, the two classes also exhibit distinct organism preference, the CFBP being found in prokaryotes, and the FCBP in eukaryotes. This review summarizes the mystery of these unique class of prolyl isomerases, focusing on their host organisms, potential physiological role, and likely routes of evolution.

X-ray structure of alisporivir in complex with cyclophilin A at 1.5†Šresolution.

Alisporivir (ALV) is an 11-amino-acid hydrophobic cyclic peptide with N-methyl-D-alanine and N-ethyl-L-valine (NEV) residues at positions 3 and 4, respectively. ALV is a non-immunosuppressive cyclosporin A (CsA) derivative. This inhibitor targets cyclophilins (Cyps), a family of proteins with peptidyl-prolyl cis/trans isomerase enzymatic activity. Cyps act as protein chaperones and are involved in numerous cellular functions. Moreover, Cyps have been shown to be an essential cofactor for the replication of many viruses, including Hepatitis C virus and Human immunodeficiency virus, and have also been shown to be involved in mitochondrial diseases. For these reasons, cyclophilins represent an attractive drug target. The structure of ALV in complex with cyclophilin A (CypA), the most abundant Cyp in humans, has been determined at 1.5 Šresolution. This first structure of the CypA-ALV complex shows that the binding of ALV is highly similar to that of CsA. The high resolution allowed the unambiguous determination of the conformations of residues 3 and 4 in ALV when bound to its target. In particular, the side-chain conformation of NEV4 precludes the interaction of the CypA-ALV complex with calcineurin, a cellular protein phosphatase involved in the immune response, which explains the non-immunosuppressive property of ALV. This study provides detailed molecular insights into the CypA-ALV interaction.

Cyclophilin J PPIase Inhibitors Derived from 2,3-Quinoxaline-6 Amine Exhibit Antitumor Activity.

Cyclophilin J (CyPJ), also called peptidylprolyl isomerase like 3, has been identified as a novel member of the cyclophilin family. Our previous research has resolved the three-dimensional structure of CyPJ and demonstrated the peptidylprolyl cis-trans isomerase (PPIase) activity of CyPJ, which can be inhibited by the common immunosuppressive drug cyclosporine A (CsA). Importantly, CyPJ is upregulated in hepatocellular carcinoma (HCC) and promotes tumor growth; CyPJ inhibition by CsA- or siRNA-based knockdown results in a remarkable suppression of HCC. These findings suggest that CyPJ may be a potential therapeutic target for HCC, and discovery of relevant inhibitors may facilitate development of a novel CyPJ-based targeting therapy. However, apart from the common inhibitor CsA, CyPJ has yet to be investigated as a target for cancer therapy. Here, we report structure-based identification of novel small molecule non-peptidic CyPJ inhibitors and their potential as antitumor lead compounds. Based on computer-aided virtual screening, in silico, and subsequently surface plasmon resonance analysis, 19 potential inhibitors of CyPJ were identified and selected for further evaluation of PPIase CyPJ inhibition in vitro. Thirteen out of 19 compounds exhibited notable inhibition against PPIase activity. Among them, the compound ZX-J-19, with a quinoxaline nucleus, showed potential for tumor inhibition; thus, we selected it for further structure-activity optimization. A total of 22 chemical derivatives with 2,3-substituted quinoxaline-6-amine modifications were designed and successfully synthesized. At least 2 out of the 22 derivatives, such as ZX-J-19j and ZX-J-19l, demonstrated remarkable inhibition of tumor cell growth, comparable to CsA but much stronger than 5-fluorouracil. These results indicate that these two small molecules represent novel potential lead compounds for CyPJ-based antitumor drug development.

Identification and Evaluation of Novel Drug Targets against the Human Fungal Pathogen Aspergillus fumigatus with Elaboration on the Possible Role of RNA-Binding Protein.

BACKGROUND: Aspergillus fumigatus is an airborne opportunistic fungal pathogen that can cause fatal infections in immunocompromised patients. Although the current anti-fungal therapies are relatively efficient, some issues such as drug toxicity, drug interactions, and the emergence of drug-resistant fungi have promoted the intense research toward finding the novel drug targets. METHODS: In search of new antifungal drug targets, we have used a bioinformatics approach to identify novel drug targets. We compared the whole proteome of this organism with yeast Saccharomyces cerevisiae to come up with 153 specific proteins. Further screening of these proteins revealed 50 potential molecular targets in A. fumigatus. Amongst them, RNA-binding protein (RBP) was selected for further examination. The aspergillus fumigatus RBP (AfuRBP), as a peptidylprolyl isomerase, was evaluated by homology modeling and bioinformatics tools. RBP-deficient mutant strains of A. fumigatus were generated and characterized. Furthermore, the susceptibility of these strains to known peptidylprolyl isomerase inhibitors was assessed. RESULTS: AfuRBP-deficient mutants demonstrated a normal growth phenotype. MIC assay results using inhibitors of peptidylprolyl isomerase confirmed a higher sensitivity of these mutants compared to the wild type. CONCLUSION: Our bioinformatics approach revealed a number of fungal-specific proteins that may be considered as new targets for drug discovery purposes. Peptidylprolyl isomerase, as a possible drug target, was evaluated against two potential inhibitors and the promising results were investigated mechanistically. Future studies would confirm the impact of such target on the antifungal discovery investigations.

Pin1 aggravates renal injury induced by ischemia and reperfusion in rats via Nrf2/HO-1 mediated endoplasmic reticulum stress

Purpose: To investigate the role of peptidyl-prolyl cis/trans isomerase 1 (Pin1) on renal ischemia-reperfusion (I/R) injury and underlying mechanism. Methods: By establishing the in vitro and in vivo models of renal I/R, the role of Pin1 was explored by using molecular assays. Results: In renal I/R, endogenous Pin1 level was up-regulated in I/R-impaired kidney. Suppression of Pin1 with juglone afforded protection against I/R-mediated kidney dysfunction, and reduced I/R-induced endoplasmic reticulum (ER) stress in vivo. Consistent with the in vivo results, repression of Pin1 with juglone or gene knockdown with si-Pin1 conferred cytoprotection and restricted hypoxia/reoxygenation (H/R)-driven ER stress in HK-2 cells. Simultaneously, further study uncovered that Nrf-2/HO-1 signals was the association between Pin1 and ER stress in response to renal I/R. In addition, Nrf-2/HO-1 signal pathway was inactivated after kidney exposed to I/R, as indicated by the down-regulation of Nrf-2/HO-1 levels. Furthermore, inhibition of Pin1 remarkably rescued the inactivation ofNrf-2/HO-1. Conclusions: Pin1 modulated I/R-mediated kidney injury in ER stress manner dependent on Nrf2-HO-1 pathway in I/R injury.

Downregulation of Peptidylprolyl isomerase A promotes cell death and enhances doxorubicin-induced apoptosis in hepatocellular carcinoma.

Peptidylprolyl isomerase A (PPIA) is a peptidyl-prolyl cis-trans isomerase that is known to play a critical role in the development of many human cancers. However, the precise biological function of PPIA in hepatocellular carcinoma (HCC) remains largely unclear. In this study, lentiviral overexpression vectors and small interfering RNA knockdown methods were employed to investigate the biological effects of PPIA in HCC. PPIA levels in HCC tissues and peritumoral tissues were detected by real-time Polymerase Chain Reaction (RT-PCR), Western blotting, and immunohistochemistry. Our results indicate that PPIA levels were significantly higher in the HCC tissues compared to the matched peritumoral tissues. Moreover, PPIA expression was significantly associated with tumor size in these tissues. Interestingly, serum PPIA (sPPIA) levels were significantly higher in healthy controls compared to the HCC patients. Knockdown or overexpression of PPIA was shown to downregulate and upregulate cell growth, respectively. Moreover, PPIA siRNA knockdown appears to promote doxorubicin-induced apoptosis in HCC cells, altering the expression of downstream apoptotic factors. In summary, our results indicate that PPIA may play a pivotal role in HCC by regulating cell growth and could serve as a novel marker and therapeutic molecular target for HCC patients.

Expression of PIN1 in Gastrointestinal Stromal Tumours and its Clinical Significance.

BACKGROUND: The malignancy of gastrointestinal stromal tumours (GIST) varies greatly. Due to the uncertainty of specific molecular pathogenesis and complexity of biological behaviour of GIST, the aggressiveness and prognosis of GIST cannot be precisely predicted. MATERIALS AND METHODS: We retrieved 40 paraffin-embedded specimens of surgically resected GIST between January 2013 and May 2015 at the Pathology Department of Yuhuangding Hospital Affiliated to Qingdao University and detected the expression of NIMA-interacting peptidylprolyl isomerase (PIN1) and Ki67, by immunohistochemical methods. RESULTS: The positivity rate of PIN1 and Ki67 in GIST was 80% and 32.5%, respectively. The expression of PIN1 was associated with risk of malignancy, tumour location, tumour size, and mitotic counts. The expression of Ki67 was also associated with risk of malignancy, tumour location, tumour size, and mitotic counts. The expression of Ki67 was positively related to the expression of PIN1. CONCLUSION: PIN1 and Ki67 may be potential factors predicting the malignancy of GIST. PIN1 may be an attractive prognostic indicator and therapeutic target for GIST.

PIN1 Suppresses the Hepatic Differentiation of Pulp Stem Cells via Wnt3a.

This study aimed to investigate the role of PIN1 on the hepatic differentiation of human dental pulp stem cells (hDPSCs) and its signaling pathway, as well as the potential therapeutic effects of hDPSC transplantation and PIN1 inhibition on CCl4 (carbon tetrachloride)-induced liver fibrosis in mice. The in vitro results showed that hepatic differentiation was suppressed by infection with adenovirus-PIN1 and promoted by PIN1 inhibitor juglone via the downregulation of Wnt3a and ß-catenin. Compared with treatment with either hDPSC transplantation or juglone alone, the combination of hDPSCs and juglone into CCl4-injured mice significantly suppressed liver fibrosis and restored serum levels of alanine transaminase, aspartate transaminase, and ammonia. Collectively, the present study shows for the first time that PIN1 inhibition promotes hepatic differentiation of hDPSCs through the Wnt/ß-catenin pathway. Furthermore, juglone in combination with hDPSC transplantation effectively treats liver fibrosis, suggesting that hDPSC transplantation with PIN1 inhibition may be a novel therapeutic candidate for the treatment of liver injury.

Silibinin Inhibits Proliferation and Migration of Human Hepatic Stellate LX-2 Cells.

BACKGROUND: Proliferation of hepatic stellate cells (HSCs) play pivotal role in the progression of hepatic fibrosis consequent to chronic liver injury. Silibinin (SBN), a flavonoid compound, has shown to possess cell cycle arresting potential against many actively proliferating cancers cell lines. The objective of this study was to evaluate the anti-proliferative and cell cycle arresting properties of SBN in rapidly proliferating human hepatic stellate LX-2 cell line. METHODS: LX-2 cells were fed with culture medium supplemented with different concentrations of SBN (10, 50 and 100 µM). After 24 and 96 h of treatment, total cell number was determined by counting. Cytotoxicity was evaluated by trypan blue dye exclusion test. The expression profile of cMyc and peroxisome proliferator-activated receptor-γ (PPAR-γ) protein expressions was evaluated by Western blotting. Oxidative stress marker genes profile was quantified using qPCR. The migratory response of HSCs was observed by scrape wound healing assay. RESULTS: SBN treatments significantly inhibit the LX-2 cell proliferation (without affecting its viability) in dose dependent manner. This treatment also retards the migration of LX-2 cells toward injured area. In Western blotting studies SBN treatment up regulated the protein expressions of PPAR-γ and inhibited cMyc. CONCLUSION: The present study shows that SBN retards the proliferation, activation and migration of LX-2 cells without inducing cytotoxicity and oxidative stress. The profound effects could be due to cell cycle arresting potential of SBN.