PTEN deficiency induces an extrahepatic cholangitis-cholangiocarcinoma continuum via aurora kinase A in mice.

BACKGROUND & AIMS: The PTEN-AKT pathway is frequently altered in extrahepatic cholangiocarcinoma (eCCA). We aimed to evaluate the role of PTEN in the pathogenesis of eCCA and identify novel therapeutic targets for this disease. METHODS: The Pten gene was genetically deleted using the Cre-loxp system in biliary epithelial cells. The pathologies were evaluated both macroscopically and histologically. The characteristics were further analyzed by immunohistochemistry, reverse-transcription PCR, cell culture, and RNA sequencing. Some features were compared to those in human eCCA samples. Further mechanistic studies utilized the conditional knockout of Trp53 and Aurora kinase A (Aurka) genes. We also tested the effectiveness of an Aurka inhibitor. RESULTS: We observed that genetic deletion of the Pten gene in the extrahepatic biliary epithelium and peri-ductal glands initiated sclerosing cholangitis-like lesions in mice, resulting in enlarged and distorted extrahepatic bile ducts in mice as early as 1 month after birth. Histologically, these lesions exhibited increased epithelial proliferation, inflammatory cell infiltration, and fibrosis. With aging, the lesions progressed from low-grade dysplasia to invasive carcinoma. Trp53 inactivation further accelerated disease progression, potentially by downregulating senescence. Further mechanistic studies showed that both human and mouse eCCA showed high expression of AURKA. Notably, the genetic deletion of Aurka completely eliminated Pten deficiency-induced extrahepatic bile duct lesions. Furthermore, pharmacological inhibition of Aurka alleviated disease progression. CONCLUSIONS: Pten deficiency in extrahepatic cholangiocytes and peribiliary glands led to a cholangitis-to-cholangiocarcinoma continuum that was dependent on Aurka. These findings offer new insights into preventive and therapeutic interventions for extrahepatic CCA. IMPACT AND IMPLICATIONS: The aberrant PTEN-PI3K-AKT signaling pathway is commonly observed in human extrahepatic cholangiocarcinoma (eCCA), a disease with a poor prognosis. In our study, we developed a mouse model mimicking cholangitis to eCCA progression by conditionally deleting the Pten gene via Pdx1-Cre in epithelial cells and peribiliary glands of the extrahepatic biliary duct. The conditional Pten deletion in these cells led to cholangitis, which gradually advanced to dysplasia, ultimately resulting in eCCA. The loss of Pten heightened Akt signaling, cell proliferation, inflammation, fibrosis, DNA damage, epigenetic signaling, epithelial-mesenchymal transition, cell dysplasia, and cellular senescence. Genetic deletion or pharmacological inhibition of Aurka successfully halted disease progression. This model will be valuable for testing novel therapies and unraveling the mechanisms of eCCA tumorigenesis.

A randomized controlled comparative study of different fluid exchange modes in urgent-start peritoneal dialysis in patients with end-stage renal disease: automated peritoneal dialysis combined with manual fluid exchange vs. manual fluid exchange alone.

During urgent-start peritoneal dialysis (USPD) in end-stage renal disease (ESRD) patients, both adequate dialysis and skill training for fluid exchange are essential. However, automated peritoneal dialysis (APD) alone or manual fluid exchange peritoneal dialysis (MPD) alone could meet the above demands. Therefore, our study combined APD with MPD (A-MPD), and compared A-MPD with MPD, aiming to find the most appropriate treatment mode. This was a single-center, prospective, randomized controlled study. All eligible patients were randomized into the MPD and A-MPD groups. All patients underwent a five-day USPD treatment 48 h after catheter implantation, and they were followed up for six months after discharge. Overall, 74 patients were enrolled in this study. Among these, 14 and 60 patients quit due to complications during USPD and completed the study (A-MPD = 31, MPD = 29), respectively. Compared with MPD, the A-MPD treatment mode had a better effect on removing serum creatinine, blood urea nitrogen, and potassium and improving serum carbon dioxide combining power levels; it had less time expenditure on the fluid exchange by nurses (p < 0.05). In addition, patients in the A-MPD group had higher scores on the skill tests than those in the MPD group (p = 0.002). However, no significant differences in short-term peritoneal dialysis (PD) complications, PD technical survival rate, or mortality were found between the two groups. Therefore, the A-MPD mode could be recommended as an adoptable and suitable PD modality for USPD in the future.

[Methylselenocysteine Promotes Etoposide Cytotoxicity by Enhancing Homotypic Gap Junctions Composed of Connexin 26].

Objective: To investigate the effect of methylselenocysteine (MSC) on the function of homotypic gap junction (GJ) composed of connexin (Cx) 26 and its regulation of chemotherapeutic drug cytotoxicity. Methods: The Tet-on HeLa cells transfected with and stably expressing Cx26 were used as the tool cells. Effects of MSC on cell growth, GJ function, and Cx26 protein expression were examined by MTT method, parachute assay, and Western blot analysis, respectively. The cytotoxicity of chemotherapeutic drugs was determined by standard colony-forming assay, and the relationship between MSC's effect on cytotoxicity of these chemotherapeutic drugs and its regulation of GJ was further analyzed. Results: In Tet-on HeLa cells, doxycycline (Dox) can induce the expression of Cx26, which could then form functional GJs. Within a concentration range of 50 µmol/L, MSC had no significant effect on HeLa cell growth. Non-toxic concentrations of MSC can enhance GJs in a concentration-dependent manner and exert its effect at the nanomolar level. This effect was associated with an induction of Cx26 protein expression by MSC. Among the three common chemotherapeutic agents with different mechanisms of action, etoposide (Eto) presented cytotoxicity differences between HeLa cells cultured at low density (nonconfluent, no GJ formed) and high density (confluent, GJ formed). What's more, the inhibitory effect of Eto combined with MSC on HeLa cell colony formation was stronger than that of Eto alone, and this effect occurred only in HeLa cells with GJ formation. Conclusion: MSC can potentiate the cytotoxicity of Eto by enhancing the GJs composed of Cx26, indicating that combined strategy of selenide and chemotherapy shows potential value in the treatment of malignant tumors.

miR-141-3p Promotes the Cisplatin Sensitivity of Osteosarcoma Cell through Targeting the Glutaminase [GLS]-Mediated Glutamine Metabolism.

AIMS: This study aimed to evaluate the roles and molecular targets of miRNA-141-3p in the cisplatin sensitivity of osteosarcoma. BACKGROUND: Osteosarcoma is one of the most common-type bone tumors, occurring mainly in children and adolescents. Cancer cells display dysregulated cellular metabolism, such as the abnormally elevated glutamine metabolism. OBJECTIVE: Non-coding RNA miRNA-141-3p has been reported to act as a tumor suppressor in osteosarcoma. Currently, the precise molecular mechanisms for the miR- 141-3p-mediated chemosensitivity through regulating glutamine metabolism remain unclear. METHODS: We collected thirty paired OS tumors and their adjacent normal tissues. The osteosarcoma cell lines [Saos-2] and normal osteoblast cells, hFOB1.19, were used for in vitro experiments. RT-qPCR and Western blot were applied for gene expression detections. Targets of miR-141-3p were predicted from starBase. The MTT and flow cytometric assays were performed to determine cell growth and apoptosis rates. The cellular glutamine metabolism was monitored by glutamine uptake assay and the glutaminase [GLS] activity assay. RESULTS: We reported that miR-141-3p were significantly downregulated in osteosarcoma tissues and cells. Overexpression of miR-141-3p suppressed OS cell growth and sensitized OS cells to cisplatin. In addition, glutamine metabolism was significantly increased in osteosarcoma. We characterized that GLS played oncogenic roles in osteosarcoma and validated GLS was a direct target of miR-141-3p in OS cells. Rescue experiments consistently demonstrated that miR-141-3p-promoted cisplatin sensitivity was achieved by targeting GLS directly. CONCLUSION: Overall, our findings revealed new molecular mechanisms of the miR-141- 3p-modulated cisplatin sensitization through targeting the GLS-glutamine metabolism pathway. This study will contribute to developing new therapeutic approaches for the treatments of chemoresistant osteosarcoma.

Activation of the Akt/FoxO3 signaling pathway enhances oxidative stress-induced autophagy and alleviates brain damage in a rat model of ischemic stroke.

Autophagy has been implicated in stroke. Our previous study showed that the FoxO3 transcription factor promotes autophagy after transient cerebral ischemia/reperfusion (I/R). However, whether the Akt/FoxO3 signaling pathway plays a regulatory role in autophagy in cerebral I/R-induced oxidative stress injury is still unclear. The present study aims to investigate the effects of the Akt/FoxO3 signaling pathway on autophagy activation and neuronal injury in vitro and in vivo. By employing LY294002 or insulin to regulate the Akt/FoxO3 signaling pathway, we found that insulin pretreatment increased cell viability, decreased reactive oxygen species production, and enhanced the expression of antiapoptotic and autophagy-related proteins following H2O2 injury in HT22 cells. In addition, insulin significantly decreased neurological deficit scores and infarct volume and increased the expression of antiapoptotic and autophagy-related proteins following I/R injury in rats. However, LY294002 showed the opposite effects under these conditions. Altogether, these results indicate that Akt/FoxO3 signaling pathway activation inhibited oxidative stress-mediated cell death through activation of autophagy. Our study supports a critical role for the Akt/FoxO3 signaling pathway in autophagy activation in stroke.

Selecting an Appropriate Experimental Animal Model for Cholangiocarcinoma Research.

Cholangiocarcinoma (CCA) is a highly aggressive biliary tree malignancy with intrahepatic and extra-hepatic subtypes that differ in molecular pathogeneses, epidemiology, clinical manifestations, treatment, and prognosis. The overall prognosis and patient survival remains poor because of lack of early diagnosis and effective treatments. Preclinical in vivo studies have become increasingly paramount as they are helpful not only for the study of the fundamental molecular mechanisms of CCA but also for developing novel and effective therapeutic approaches of this fatal cancer. Recent advancements in cell and molecular biology have made it possible to mimic the pathogenicity of human CCA in chemical-mechanical, infection-induced inflammatory, implantation, and genetically engineered animal models. This review is intended to help investigators understand the particular strengths and weaknesses of the currently used in vivo animal models of human CCA and their related modeling techniques to aid in the selection of the one that is the best for their research needs.

Peritoneal M2 macrophage-derived extracellular vesicles as natural multitarget nanotherapeutics to attenuate cytokine storms after severe infections.

Cytokine storms are a primary cause of multiple organ damage and death after severe infections, such as SARS-CoV-2. However, current single cytokine-targeted strategies display limited therapeutic efficacy. Here, we report that peritoneal M2 macrophage-derived extracellular vesicles (M2-EVs) are multitarget nanotherapeutics that can be used to resolve cytokine storms. In detail, primary peritoneal M2 macrophages exhibited superior anti-inflammatory potential than immobilized cell lines. Systemically administered M2-EVs entered major organs and were taken up by phagocytes (e.g., macrophages). M2-EV treatment effectively reduced excessive cytokine (e.g., TNF-α and IL-6) release in vitro and in vivo, thereby attenuating oxidative stress and multiple organ (lung, liver, spleen and kidney) damage in endotoxin-induced cytokine storms. Moreover, M2-EVs simultaneously inhibited multiple key proinflammatory pathways (e.g., NF-κB, JAK-STAT and p38 MAPK) by regulating complex miRNA-gene and gene-gene networks, and this effect was collectively mediated by many functional cargos (miRNAs and proteins) in EVs. In addition to the direct anti-inflammatory role, human peritoneal M2-EVs expressed angiotensin-converting enzyme 2 (ACE2), a receptor of SARS-CoV-2 spike protein, and thus could serve as nanodecoys to prevent SARS-CoV-2 pseudovirus infection in vitro. As cell-derived nanomaterials, the therapeutic index of M2-EVs can be further improved by genetic/chemical modification or loading with specific drugs. This study highlights that peritoneal M2-EVs are promising multifunctional nanotherapeutics to attenuate infectious disease-related cytokine storms.

PHF5A Contributes to the Maintenance of the Cancer Stem-like Phenotype in Non-Small Cell Lung Cancer by Regulating Histone Deacetylase 8.

OBJECTIVE: Cancer stem-like cells (CSLCs) are closely associated with tumor recurrence, metastasis, and drug-resistance. PHD-finger domain protein 5A (PHF5A) is related to tumorigenesis and development of non-small cell lung cancer (NSCLC). The role and regulatory mechanism of PHF5A in CSLCs of NSCLC remain unclear. This study aimed to identify the biological characteristics of CSLCs and the role of PHF5A in maintaining stemness of NSCLC. METHODS: H1299-spheres and A549-spheres were obtained by oncosphere-forming assay and CSLCs by flow cytometry. Expression of CD133, aldehyde dehydrogenase isoform 1, E-cadherin, vimentin, PHF5A, and histone deacetylase 8 (HDAC8) was tested using immunofluorescence staining, qRT-PCR, and Western blotting. CCK-8 and Transwell assays were employed to determine proliferation, migration, and invasion ability of CSLCs and adherent monolayer cells in NSCLC. We regulated PHF5A expression and HDAC activity in CSLCs to explore the mechanism of PHF5A in stemness maintenance and analyzed expression of target proteins in NSCLC tissues. RESULTS: Compared with monolayer cells, CSLCs showed a decreased response to cisplatin-mediated inhibition of proliferation, increased migration and invasion, and high expression of PHF5A and HDAC8, accompanied by EMT marker alterations. Targeted knockdown of PHF5A in CSLCs of NSCLC resulted in diminished stemness phenotypes and HDAC8 expression, whereas inhibition of HDAC activity affected stemness maintenance. Moreover, the expression of target proteins showed consistent changes in NSCLC tissues. CONCLUSIONS: Compared with monolayer cells, cancer stem-like phenotype properties of NSCLC were altered, PHF5A was involved in stemness maintenance of CSLCs, and this process may be related to the activation of HDAC8.

Methylselenocysteine Potentiates Etoposide-Induced Cytotoxicity by Enhancing Gap Junction Activity.

Homomeric or heteromeric connexin (Cx) hemichannels-composed gap junction (GJ) intercellular channel can mediate direct cell-to-cell communication. Accumulating studies indicate that GJs potentiate the cytotoxicity of antitumor drugs in malignant cells. Methylselenocysteine (MSC), a selenium compound from garlic, has been reported to modulate the activity of antineoplastic drugs, but the underlying mechanism remains unclear. This study investigates the efficacy of MSC on chemotherapeutic drugs-induced cytotoxicity and the relationship between this effect and the regulation of GJ function by MSC. Firstly, a doxycycline-regulated HeLa cell line expressing heteromeric Cx26/Cx32 was used as a tool. Etoposide, but not cisplatin or 5-fluorouracil, showed remarkable cytotoxicity in high-density (with GJ formation) cultures than in low-density (without GJ formation) in transformed HeLa cells. And cell density had no effect on etoposide-mediated cytotoxicity in the absence of Cx expression. MSC substantially enhanced etoposide-induced cytotoxicity, and this effect was only detected in the presence of functional GJs. Subsequently, MSC potentiated structural Cx expression as evidenced by increased dye coupling, but no alteration in Cx mRNA expression level in either transformed or primary cancer cell lines. Finally, a redox mechanism involving glutathione (GSH) was found to be related to the posttranscriptional modulation of Cx expression by MSC in HeLa cells. In conclusion, we provide the novel finding that MSC increases etoposide-mediated cytotoxicity by enhancing GJ activity, due to elevated Cx expression through a GSH-dependent posttranscriptional mechanism. More generally, the study highlights potential benefit of the combination of GJ modulators and chemotherapeutic agents in anticancer treatment.

Iron Deficiency is Associated With Platelet Count Elevation in Patients With Dialysis-dependent Chronic Kidney Disease.

OBJECTIVE: Iron deficiency is common in patients with end-stage renal disease (ESRD). Platelet count changes may reflect iron status, but the relationship between platelet count and iron indices is unclear in patients with ESRD. METHODS: We conducted a retrospective study in 1,167 patients with ESRD from 2012 to 2017 in West China Hospital. Baseline data were used to analyze the relationship between the platelet count and iron indices. Patients were followed up for 3 years. RESULTS: Patients with iron deficiency (both absolute and functional) had a higher platelet count than those without iron deficiency (174 ± 61 × 109/L vs. 153 ± 58 × 109/L, P < .001). Receiver operating characteristic analysis showed a weak predictive power of platelet count on absolute iron deficiency (area under curve 0.620; cutoff value > 137 × 109/L, sensitivity 76%, specificity 43%) and functional iron deficiency (area under curve 0.540; cutoff value > 124 × 109/L, sensitivity 77%, specificity 32%). Platelet count was negatively correlated with ferritin (Spearman's rho [ρ] -0.1547, P < .001), transferrin saturation (ρ = -0.1895, P < .001), and serum iron (ρ = -0.1466, P < .001). The abovementioned correlations remained significant in multivariate regression (ß -0.7285, 95% confidence interval [CI] -1.0757 to -0.3814; ß -.00347, 95% CI -0.0520 to -0.0174; ß -0.0097, 95% CI -0.0159 to -0.0035, respectively). In unadjusted and adjusted Cox regression models, neither baseline platelet count nor relative thrombocytosis was associated with 3-year mortality. CONCLUSION: There was a weak but significant platelet count elevation in patients with ESRD and with iron deficiency.

Regorafenib-induced renal-limited thrombotic microangiopathy: a case report and review of literatures.

BACKGROUND: Regorafenib belongs to a sub-group of small-molecule multi-targeted tyrosine kinase inhibitors(TKIs). In various studies with respect to the side-effect of regorafenib, drug-associated proteinuria standardly qualified to be defined as nephrotic syndrome was rarely reported as well as the relation of regorafenib with the occurrence and development of thrombotic microangiopathy (TMA). CASE PRESENTATION: In this case report and literature review, we presented a 62-year-old patient receiving regorafenib for metastatic colon cancer, manifesting abundant proteinuria, in which TMA was also diagnosed through renal biopsy. As far as we were concerned, this was the first reported in terms of regorafenib-induced TMA confirmed by renal biopsy. CONCLUSION: This case indicates that regorafenib, a kind of TKIs may result in TMA, which is a rare but life-threatening complication of cancer treatment drug. Insights from this case might help physicians diagnose rare forms of TMA and adjust treatment for patients in a timely manner.

Role of complement 3 in TNF-α-induced mesenchymal transition of renal tubular epithelial cells in vitro.

Injured renal tubular epithelial cells (RTECs) have been recently thought to directly contribute to the accumulation of myofibroblasts in renal tubulointerstitial fibrosis through a process of epithelial to mesenchymal transition (EMT). However, the factors inducing RTECs to undergo EMT and the underlying mechanisms need to be further elucidated. This study aimed to determine the EMT-inducing activity of proinflammatory cytokine TNF-α and the role for complement 3 (C3) in this activity in an in vitro model of human RTECs (HK-2 cells). Wild type HK-2 cells were treated with TNF-α, IFN-γ or C3a; C3 siRNA- or control siRNA-carrying HK-2 cells were treated with TNF-α. Changes in the cell morphology and phenotype were assessed by microscopy, RT-PCR, western blotting, and immunostaining. TNF-α effectively induced HK-2 cells to express C3 and to transform into morphologically myofibroblast-like cells that lost E-cadherin (a classical epithelial cell marker) expression but acquired alpha-smooth muscle actin (α-SMA, a classical myofibroblast differentiation marker) expression. C3 siRNA robustly attenuated all the morphologic and phenotypic changes induced by TNF-α but the control siRNA showed no effect. Our preliminary observations suggest that TNF-α may induce EMT in RTECs through inducing C3 expression.

Complications and conversions in myeloproliferative disorders: an analysis of 356 cases.

OBJECTIVE: To investigate the complications and conversions in myeloproliferative disorders (MPD). METHODS: Three hundred and fifty six patients with MPD were reviewed, including 78 with etiologic thrombocythemia (ET), 93 with primary myelofibrosis (MF), 185 with polythythemia vera (PV). The clinical observation, follow-up, analysis with SPSS statistic software were performed. RESULTS: Out of the 356 cases, 101 (28.5%) developed thromboembolic events, 81 (22.8%) hemorrhage, 60 (16.9%) hypertension, 20 (5.6%) coronary heart disease, 3 (0.8%) hemolysis and 1 (0.3%) gastrointestinal ulcer, 2 (0.6%) calculus and 1 (0.3%) bone marrow necrosis. Twenty four patients (6.7%) developed MF (9 in ET, 15 in PV), 2 (0.6%) erythrocytosis (1 in ET, 1 in MF), 3 (0.8%) thrombocythemia (all in PV), 5 (1.4%) acute leukemia (2 in ET, 3 in MF) and 1 (0.3%) multiple myeloma (in ET). Eleven cases (3.1%) died, 5 (1.4%) from acute leukemia, 2 (0.6%) fatal hemorrhages, 1 (0.3%) each myocardial infarction and infectious shock, 2 (0.6%) unknown causes. CONCLUSION: Embolism and bleeding were the main complications in MPD. Conversions among ET, MF and PV hematological malignancies could occur.