A separate-dural-incision method of extradural dumbbell spinal schwannoma resection: cumulative experience at a single center.

OBJECTIVE: To present our experience in the surgical management of completely extradural dumbbell spinal schwannomas with a new surgical strategy. METHOD: This study is a case series of patients treated at the Neurosurgery Department of the First Affiliated Hospital of USTC, between January 2018 and June 2021. RESULTS: 24 patients met the inclusion criteria, with cervical and lumbar spines being the most frequent locations. All patients underwent surgical treatment. Total gross resection was accomplished in all patients. Two cases had numbness and no case exhibited motor deficit. There was no postoperative CSF leakage or wound infection. CONCLUSION: Based on a limited number of observations, we conclude that our technique was feasible and effective for the treatment of extradural dumbbell spinal schwannomas. CLINICAL TRIAL: http://www.chictr.org.cn/ , No. ChiCTR2400086171.

Impact of metabolic dysfunction-associated steatotic liver disease on the efficacy of immunotherapy in patients with chronic hepatitis B-related hepatocellular carcinoma.

OBJECTIVE: To investigate the impact of metabolic dysfunction-associated steatotic liver disease (MASLD) on the efficacy of immune checkpoint inhibitor (ICI)-based therapy in patients with chronic hepatitis B (CHB)-related hepatocellular carcinoma (HCC). METHODS: A total of 155 patients with CHB-related HCC who received ICI-based therapy (in the Department of Hepatology, Tianjin Second People's Hospital and Department of Hepatobiliary Oncology, Tianjin Medical University Cancer Institute & Hospital) between April 2021 and December 2023 were evaluated. Patients were divided into two groups: MASLD concurrent with CHB [MASLD-CHB] (n = 38), and CHB (n = 117). RESULTS: The median progression-free survival (PFS, 6.9 months vs. 9.3 months; P = 0.001), progressive disease (57.89% vs. 37.61%; P = 0.028), and disease control rate (42.11% vs. 62.39%; P = 0. 028) in the MASLD-CHB group were significantly worse than the CHB group. The median overall survival was not attained. The percentage of CD4+PD1+ (17. 56% vs. 8.89%; P < 0.001) and CD8+PD1+ T cells (10.50% vs. 7.42%; P = 0.005) in patient samples from the MASLD-CHB group were significantly higher than the CHB group. Concurrent MASLD [hazard ratio (HR) = 1.921; 95% CI, 1.138-3.245; P = 0.015] and alpha-fetoprotein levels after 3 months of treatment (HR = 2.412; 95% CI, 1.360-4.279; P = 0.003) were independent risk factors for PFS in all patients. CONCLUSIONS: ICI-based therapy in patients with CHB-related HCC and concurrent MASLD resulted in poorer efficacy and shorter PFS compared to patients with CHB-related HCC alone.

Noninvasive tests maintain high accuracy for advanced fibrosis in chronic hepatitis B patients with different nomenclatures of steatotic liver disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a new nomenclature proposed in 2023. We aimed to compare the diagnostic efficacy of noninvasive tests (NITs) for advanced fibrosis under different nomenclatures in patients with chronic hepatitis B (CHB). A total of 844 patients diagnosed with CHB and concurrent steatotic liver disease (SLD) by liver biopsy were retrospectively enrolled and divided into four groups. The performances of fibrosis-4 (FIB-4), gamma-glutamyl transpeptidase to platelet ratio index (GPRI), aspartate aminotransferase to platelet ratio index (APRI), and liver stiffness measurement (LSM) were compared among the four groups. The four NITs showed similar diagnostic efficacy for nonalcoholic fatty liver disease (NAFLD), MASLD, and metabolic dysfunction-associated fatty liver disease (MAFLD) in patients with CHB with advanced fibrosis. LSM showed the most stable accuracy for NAFLD (AUC = 0.842), MASLD (AUC = 0.846), and MAFLD (AUC = 0.863) compared with other NITs (p < 0.05). Among the four NITs, APRI (AUC = 0.841) and GPRI (AUC = 0.844) performed best in patients with CHB & MetALD (p < 0.05). The cutoff value for GPRI in patients with CHB & MetALD was higher than that in the other three groups, while further comparisons of NITs at different fibrosis stages showed that the median GPRI of CHB & MetALD (1.113) at F3-4 was higher than that in the CHB & MASLD group (0.508) (p < 0.05). Current NITs perform adequately in patients with CHB and SLD; however, alterations in cutoff values for CHB & MetALD need to be noted.

Direct-acting antivirals failed to reduce the incidence of hepatocellular carcinoma occurrence in hepatitis C virus associated cirrhosis: A real-world study.

BACKGROUND: Direct-acting antivirals (DAAs) revolutionized the treatment of chronic hepatitis C virus (HCV)-associated disease achieving high rates of sustained virological response (SVR). However, whether DAAs can reduce the occurrence of hepatocellular carcinoma (HCC) in patients with HCV-associated cirrhosis who are at high risk have not been concluded. AIM: To investigate the effect of DAAs on the occurrence of HCC in patients with HCV-associated cirrhosis after achieving SVR. METHODS: Of 427 inpatients with HCV-associated cirrhosis were enrolled in Tianjin Second People's Hospital from January 2014 to April 2020. 118 patients weren't received antiviral treatment with any reasons named non-antiviral treatment group, and 236 patients obtained from the 309 DAAs treatment patients according to the propensity score matching named DAAs treatment group. Demographic information and laboratory data were collected from baseline and the following up. Kaplan-Meier curve and Log-Rank test were used to compare the incidence and cumulative incidence of HCC between the two groups. Cox proportional risk regression was used to re-evaluate the risk factors for HCC. RESULTS: HCC incidence was 4.68/100PY (95%CI, 3.09-6.81) in the DAAs treatment group, while it was 3.00/100PY (95%CI, 1.50-5.37) in the non-antiviral treatment group, and the relative risk was 1.82 (95%CI, 0.93-3.53, P > 0.05). The incidence of HCC at 12, 24, 36 and 48 months was 3.39%, 6.36%, 8.47% and 10.17% in the DAAs treatment group, and it was 0%, 0%, 3.39% and 9.32% in the non-antiviral treatment group, respectively. Age > 58 [hazard ratio (HR) = 1.089; 95%CI, 1.033-1.147; P = 0.002] and liver stiffness measurement > 27.85 kPa (HR = 1.043; 95%CI, 1.022-1.065; P = 0.000) were risk factors for HCC in all patients (n = 427), and DAAs treatment didn't show protective efficacy. CONCLUSION: DAAs treatment seems failed to reduce the incidence of HCC occurrence in HCV-associated cirrhosis in 48 months, and even increased the incidence of HCC in 36 months.

Postoperative epidural hematoma as a rare complication after intracranial tumor resection: a case series report and causes analysis.

BACKGROUND: To review the treatment and the causes of postoperative epidural hematoma (PEDH) after intracranial tumor resection. METHOD: A retrospective case study was conducted to examine a series of patients who developed PEDH as a complication following intracranial tumor resection between January 2016 and June 2021. The study collected data from hospital charts, including clinical status at admission, imaging results, histopathologic findings, surgical management, complications, and outcomes. Causes of PEDH were evaluated through a review of operative notes and discussions with the surgical team. RESULTS: Twenty-five patients (10 males, 15 females; median age 42 years, range 11-61 years; median medical history 27 months, range 1-96 months) were enrolled in the study. Regarding tumor location, 16 cases exhibited supratentorial brain tumors, 4 cases had infratentorial brain tumors, 2 cases of tumors occurred in the petroclival region, 2 cases in the peritorcular region, and 1 case in the pineal region. Four of these cases were complicated with supratentorial hydrocephalus. The 25 cases in this study were classified into four types based on location. Type 1 refers to EDHs that occur at the adjacent site of the operative field without involvement of the surgical area. Type 2 includes hematomas that occur at the adjacent site of the surgical area and the surgical area. Type 3 includes EDHs that occur in distant areas, and type 4 involves EDHs in the surgical field. The numbers of cases of types 1, 2, 3, and 4 PEDHs were 16, 2, 3, and 4 cases, respectively. Most PEDHs were associated with reduced ICP after craniotomy due to intracranial tumor resection and substantial loss of CSF. All patients achieved satisfactory outcomes after hematoma evacuation. CONCLUSION: The decrease in ICP resulting from intracranial tumor resection and CSF loss might lead to PEDHs. By employing optimized surgical techniques and meticulous patient management to prevent rapid decreases in ICP and dural detachment, we can potentially lower the incidence of PEDHs. Additionally, prompt evacuation of hematomas can contribute to positive outcomes.

Development of cannabidiol derivatives as potent broad-spectrum antibacterial agents with membrane-disruptive mechanism.

The emergence of antibiotic resistance has brought a significant burden to public health. Here, we designed and synthesized a series of cannabidiol derivatives by biomimicking the structure and function of cationic antibacterial peptides. This is the first report on the design of cannabidiol derivatives as broad-spectrum antibacterial agents. Through the structure-activity relationship (SAR) study, we found a lead compound 23 that killed both Gram-negative and Gram-positive bacteria via a membrane-targeting mechanism of action with low resistance frequencies. Compound 23 also exhibited very weak hemolytic activity, low toxicity toward mammalian cells, and rapid bactericidal properties. To further validate the membrane action mechanism of compound 23, we performed transcriptomic analysis using RNA-seq, which revealed that treatment with compound 23 altered many cell wall/membrane/envelope biogenesis-related genes in Gram-positive and Gram-negative bacteria. More importantly, compound 23 showed potent in vivo antibacterial efficacy in murine corneal infection models caused by Staphylococcus aureus or Pseudomonas aeruginosa. These findings would provide a new design idea for the discovery of novel broad-spectrum antibacterial agents to overcome the antibiotic resistance crisis.

Activation of Sphingomyelin Phosphodiesterase 3 in Liver Regeneration Impedes the Progression of Colorectal Cancer Liver Metastasis Via Exosome-Bound Intercellular Transfer of Ceramides.

BACKGROUND & AIMS: The machinery that prevents colorectal cancer liver metastasis (CRLM) in the context of liver regeneration (LR) remains elusive. Ceramide (CER) is a potent anti-cancer lipid involved in intercellular interaction. Here, we investigated the role of CER metabolism in mediating the interaction between hepatocytes and metastatic colorectal cancer (CRC) cells to regulate CRLM in the context of LR. METHODS: Mice were intrasplenically injected with CRC cells. LR was induced by 2/3 partial hepatectomy (PH) to mimic the CRLM in the context of LR. The alteration of corresponding CER-metabolizing genes was examined. The biological roles of CER metabolism in vitro and in vivo were examined by performing a series of functional experiments. RESULTS: Induction of LR augmented apoptosis but promoted matrix metalloproteinase 2 (MMP2) expression and epithelial-mesenchymal transition (EMT) to increase the invasiveness of metastatic CRC cells, resulting in aggressive CRLM. Up-regulation of sphingomyelin phosphodiesterase 3 (SMPD3) was determined in the regenerating hepatocytes after LR induction and persisted in the CRLM-adjacent hepatocytes after CRLM formation. Hepatic Smpd3 knockdown was found to further promote CRLM in the context of LR by abolishing mitochondrial apoptosis and augmenting the invasiveness in metastatic CRC cells by up-regulating MMP2 and EMT through promoting the nuclear translocation of ß-catenin. Mechanistically, we found that hepatic SMPD3 controlled the generation of exosomal CER in the regenerating hepatocytes and the CRLM-adjacent hepatocytes. The SMPD3-produced exosomal CER critically conducted the intercellular transfer of CER from the hepatocytes to metastatic CRC cells and impeded CRLM by inducing mitochondrial apoptosis and restricting the invasiveness in metastatic CRC cells. The administration of nanoliposomal CER was found to suppress CRLM in the context of LR substantially. CONCLUSIONS: SMPD3-produced exosomal CER constitutes a critical anti-CRLM mechanism in LR to impede CRLM, offering the promise of using CER as a therapeutic agent to prevent the recurrence of CRLM after PH.

Retractorless Surgery for Petroclival Meningiomas via the Subtemporal Approach: A Try to Reduce Brain Retraction Injury.

Purpose: To present our experience with retractorless surgery for resection of petroclival meningiomas (PCMs) via the subtemporal approach with routine operative instruments. Methods: Clinical data of patients with PCMs who received surgical treatments via subtemporal approach were retrospectively analyzed. Patient demographics, duration of operation, extent of resection, postoperative brain injury rate, postoperative complication, and surgical outcome were reviewed. Results: Twenty-nine consecutive patients with retractorless surgery via subtemporal approach performed between November 2018 and November 2021. The gross total resection rate was 82.8% (N = 24). The incidence of postoperative temporal lobe injury was 3.4% (N = 1). All the procedures were completed without fixed retraction or other specialized instruments. Conclusions: Retractorless surgery via subtemporal approach is a reliable treatment option for PCMs, which can be completed with routine operative instruments.

CircularLRRC7 is a Potential Tumor Suppressor Associated With miR-1281 and PDXP Expression in Glioblastoma.

Circular RNAs (circRNAs) are usually enriched in neural tissues, yet about 80% circRNAs have lower expression in gliomas relative to normal brains, highlighting the importance of circRNAs as tumor suppressors. However, the clinical impact as well as the pathways regulated by the tumor-suppressive circRNAs remain largely unknown in glioblastoma (GBM). Through bioinformatic analysis followed by experimental validation, we found that hsa_circ_0114014 (circLRRC7) was dramatically down-regulated in GBM when compared with normal brain tissues (p < 0.0001). GBM patients with a lower circLRRC7 expression had poorer progression-free survival (PFS, p < 0.05) and overall survival (OS, p < 0.05). Analyses of the predicted target miRNAs of circLRRC7 in CSCD and CRI databases, in combination with the miRNA expression data in GBMs and normal brains from GSE database, revealed miR-1281 as a potential downstream target of circLRRC7. Subsequently, the target genes of hsa-mir-1281 were predicted by TargetScan, miRDB and miRNATAR databases. Intersection analysis and correlation test indicated that PDXP was a potential target of miR-1281. In summary, circLRRC7 may be a tumor suppressor that associated with miR-1281 and PDXP expression in GBM, which may provide novel therapeutic targets for GBM treatment.

Individualized Perioperative Blood Pressure Management for Adult Moyamoya Disease: Experience from 186 Consecutive Procedures.

BACKGROUND: In adult patients with moyamoya disease (MMD) underwent combined revascularization, cerebral infarction during the acute postoperative phase is common and can lead to neurological dysfunction after revascularization in MMD patients. The aim of this study was to share the experience of individualized perioperative blood pressure (BP) management for adult MMD patients in one single center. METHODS: We retrospectively reviewed 144 adult patients with MMD who underwent 186 procedures of combined revascularization at our institution from March 2013 to July 2019. Clinical features and outcomes were analyzed, in particular regarding cerebral infarction and hyperperfusion syndrome (HPS). All of the patients received individualized management perioperatively, especially about the blood pressure management according to the characteristics of moyamoya disease. RESULTS: Postoperative cerebral infarction and HPS within 14 days after revascularization were recorded. Cerebral infarction occurred in four (2.1%) procedures among four patients. No patients suffered from a malignant cerebral infarction and only one patient had permanent neurological deficits. The incidence of HPS was 10.8% and no one presented with intracranial hemorrhage. All of the symptoms were reversible without any brain parenchymal injury. CONCLUSIONS: Our findings suggest that we can decrease the incidence and extent of cerebral infarction in adult MMD patients following combined revascularization by individualized perioperative BP management.

Circulating miR-451a levels as a potential biomarker to predict the prognosis of patients with multiple myeloma.

The natural course of multiple myeloma (MM) varies greatly between patients. The Revised MM International Staging System (R-ISS) identifies high-risk patients, but it is unsuitable for assessing minimal residual disease (MRD). Furthermore, the focal location of myeloma cells and clonal evolution often produce false negative results in flow cytometry. Extracellular microRNA (miRNA/miR) expression levels are stable in bodily fluids, and are retrievable and measurable from fresh or archived serum or plasma samples. Therefore, the present study aimed to investigate the clinical utility of circulating miRNA levels in patients with MM, particularly miR-451a, which is commonly downregulated in MM, and whether it could predict the prognosis and relapse of patients with MM. In total, 66 patients with MM, stratified using the R-ISS criteria, were recruited, while 10 healthy subjects (transplantation donors) were enrolled as controls. Reverse transcription-quantitative PCR was used to evaluate miR-451a expression in bone marrow (BM) and in the circulation. IL-6 levels were measured using ELISA, while western blotting was conducted to analyze the protein expression levels of the IL-6 receptor (IL-6R). During follow-up, MRD was assessed via multiparameter flow cytometry (MFC). miR-451a was identified to target IL-6R using a dual-luciferase reporter assay. Circulating miR-451a levels were low in patients with MM, and was found to be 0.39 times that of the control group (U=4.00; P<0.001). Among the 66 patients with MM, the median level of miR-451a was 0.73 and 0.41 times that of the control group in R-ISS stage I MM (15 patients) and R-ISS stage II stage (17 patients), respectively; patients with R-ISS stage III MM (34 patients) had the lowest level, at 0.24 times the value of the control group. Circulating miR-451a levels had a strong positive correlation with miR-451a levels in BM, but negatively correlated with IL-6 and IL-6R levels. After two courses of consolidation chemotherapy, 19 patients achieved complete remission, 10 of whom presented steady circulating miR-451a levels during follow-up; the other nine patients had an abrupt decrease in circulating miR-451a levels. The turning points in the trend appeared 4-8 weeks before positive results were obtained via MFC, and 4-16 weeks before clinical relapse. Moreover, miR-451a overexpression notably downregulated the expression of the IL-6R mRNA and protein. Collectively, circulating miR-451a levels potentially represent a novel biomarker to monitor MRD and predict relapse.

Identification of Long Noncoding RNA Associated ceRNA Networks in Rosacea.

Rosacea is a chronic and relapsing inflammatory cutaneous disorder with highly variable prevalence worldwide that adversely affects the health of patients and their quality of life. However, the molecular characterization of each rosacea subtype is still unclear. Furthermore, little is known about the role of long noncoding RNAs (lncRNAs) in the pathogenesis or regulatory processes of this disorder. In the current study, we established lncRNA-mRNA coexpression networks for three rosacea subtypes (erythematotelangiectatic, papulopustular, and phymatous) and performed their functional enrichment analyses using Gene Onotology, KEGG, GSEA, and WGCNA. Compared to the control group, 13 differentially expressed lncRNAs and 525 differentially expressed mRNAs were identified in the three rosacea subtypes. The differentially expressed genes identified were enriched in four signaling pathways and the GO terms found were associated with leukocyte migration. In addition, we found nine differentially expressed lncRNAs in all three rosacea subtype-related networks, including NEAT1 and HOTAIR, which may play important roles in the pathology of rosacea. Our study provided novel insights into lncRNA-mRNA coexpression networks to discover the molecular mechanisms involved in rosacea development that can be used as future targets of rosacea diagnosis, prevention, and treatment.

Impact of ultrasound-guided erector spinae plane block on postoperative quality of recovery in video-assisted thoracic surgery: A prospective, randomized, controlled trial.

STUDY OBJECTIVE: Regional anesthesia improves postoperative analgesia and enhances the quality of recovery (QoR) after surgery. We examine the efficacy of ultrasound-guided erector spinae plane block (ESPB) on QoR after video-assisted thoracic surgery (VATS). DESIGN: Prospective, randomized, double-blinded, placebo-controlled trial. SETTING: Single institution, tertiary university hospital. PATIENTS: Adult patients who scheduled for VATS under general anesthesia were enrolled in the study. INTERVENTIONS: We randomly allocated patients to receive preoperative ultrasound-guided ESPB with 25 ml of either 0.5% ropivacaine (ESPB group) or normal saline (Control group). MEASUREMENTS: The primary outcome was QoR as measured by the 40-item QoR questionnaire (QoR-40) score at postoperative day 1. Secondary results were post-anesthesia care unit (PACU) discharge time, acute postoperative pain, cumulative opioid consumption, the incidence of postoperative nausea or vomiting (PONV), and patient satisfaction. MAIN RESULTS: The global QoR-40 score at postoperative day 1 (median, interquartile range) was significantly higher in the ESPB group (174, 170 to 177) than the control group (161.5, 160 to 165), estimated median difference 11 (95% CI 9 to 13, P < 0.001). Compared with the control group, single-injection of ESPB reduced PACU discharge time, acute postoperative pain, and cumulative opioid consumption. Correspondingly, the median patient satisfaction scores were higher in the ESPB group than the control group (9 versus 7, P < 0.001). CONCLUSION: Preoperative single-injection thoracic ESPB with ropivacaine improves QoR, postoperative analgesia, and patient satisfaction after VATS.

Discovery of novel akt1 inhibitor induces autophagy associated death in hepatocellular carcinoma cells.

In this study, a series of thieno [2,3-d]pyrimidine derivatives were designed, synthesized and evaluated as novel AKT1 inhibitors. In vitro antitumor assay results showed that compounds 9d-g and 9i potently suppressed the enzymatic activities of AKT1 and potently inhibited the proliferation of HepG2, Hep3B, Huh-7 and SMMC-7721 cancer cell lines. Among these derivatives, the compound 9f demonstrated the best inhibitory activities on AKT1 (IC50 = 0.034 µM) and Huh-7 cell (IC50 = 0.076 µM). A panel of biological assays showed that compound 9f suppressed the cellular proliferation of Huh-7 through Akt/mTOR signaling pathway mediated autophagy mechanism. Furthermore, the antitumor capacity of 9f was validated in the subcutaneous Huh-7 xenograft models. Together, our results demonstrate that a novel small-molecule Akt1 inhibitor induces autophagy associated death in hepatocellular carcinoma, which may afford a potential drug candidate for targeted cancer therapy.

IDUA, NDST1, SAP30L, CRYBA4, and SI as novel prognostic signatures clear cell renal cell carcinoma.

Carcinoma of the kidney is one of the most prevalent carcinoma worldwide. The majority types of carcinoma are clear cell renal cell carcinoma (CCRCC), which consist more than 80% of the cases. As a genetically diverse disease, identification of prognosis-related genes has utmost importance in the early diagnosis and prognosis of the CCRCC. In this study, we performed gene expression profiling to identify prognosis-related genes for CCRCC. In addition, we developed and validated a gene signature-based risk score to comprehensively assess the prognostic function of differentially expressed genes. Furthermore, we performed a ROC analysis to identify the optimal cut-off point for classification risk level of the patients. Univariate Cox regression models were used to assess the association between differentially expressed genes in relation to the prognosis of patients with different stages of CCRCC. Five genes were identified significantly differentially expressed in CCRCC and associated with their survival time, namely: IDUA, NDST1, SAP30L, CRYBA4, and SI. A 5-gene signature-based risk score was developed based on the Cox coefficient of the individual genes. The prognostic value of this risk score was validated in an internal testing data set. In summary, a gene-based risk score was identified and validated, which can predict CCRCC patient survival. The potential functions of this gene expression signature and individual differentially expressed gene as prognostic targets of CCRCC were revealed by this study. Furthermore, these findings may have important implications in the understanding of the potential therapeutic method for the CCRCC patients.

MicroRNA-93 promotes bladder cancer proliferation and invasion by targeting PEDF.

OBJECTIVE: MicroRNA-93 (miR-93) is upregulated in the urine of patients with bladder cancer (BC). Here, we investigated the role of miR-93 in BC progression and explored the underlying mechanism. METHODS: miR-93 expression in BC tissues and cells was detected by real time-polymerase chain reaction. The effects of miR-93 and pigment epithelium-derived factor (PEDF) on cell proliferation and invasion were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Transwell assays. The binding of miR-93 to the 3'-untranslated region of PEDF was identified by the luciferase reporter assay. RESULTS: miR-93 expression was higher in BC tissues than in normal controls, and its expression was associated with tumor stage and node stage. Inhibition of miR-93 suppressed the proliferation and invasion of BC cells. PEDF was identified as a target of miR-93 and shown to mediate the effect of miR-93 on cell proliferation and invasion. CONCLUSIONS: The present data suggested that miR-93 promoted BC cell proliferation and invasion by targeting PEDF, providing new biomarkers and targets for BC diagnosis and treatment.

Itch inhibits IL-17-mediated colon inflammation and tumorigenesis by ROR-γt ubiquitination.

Dysregulated expression of interleukin 17 (IL-17) in the colonic mucosa is associated with colonic inflammation and cancer. However, the cell-intrinsic molecular mechanisms by which IL-17 expression is regulated remain unclear. We found that deficiency in the ubiquitin ligase Itch led to spontaneous colitis and increased susceptibility to colon cancer. Itch deficiency in the TH17 subset of helper T cells, innate lymphoid cells and γδ T cells resulted in the production of elevated amounts of IL-17 in the colonic mucosa. Mechanistically, Itch bound to the transcription factor ROR-γt and targeted ROR-γt for ubiquitination. Inhibition or genetic inactivation of ROR-γt attenuated IL-17 expression and reduced spontaneous colonic inflammation in Itch(-/-) mice. Thus, we have identified a previously unknown role for Itch in regulating IL-17-mediated colonic inflammation and carcinogenesis.

The E3 ubiquitin ligase Itch inhibits p38α signaling and skin inflammation through the ubiquitylation of Tab1.

Deficiency in the E3 ubiquitin ligase Itch causes a skin-scratching phenotype in mice. We found that there was increased phosphorylation and activation of the mitogen-activated protein kinase p38α in spontaneous and experimentally induced skin lesions of Itch-deficient (Itch-/-) mice. Itch bound directly to the TGF-ß-activated kinase 1-binding protein 1 (Tab1) through a conserved PPXY motif and inhibited the activation of p38α. Knockdown of Tab1 by short hairpin RNA attenuated the prolonged p38α phosphorylation exhibited by Itch-/- cells. Similarly, reconstitution of Itch-/- cells with wild-type Itch, but not the ligase-deficient Itch-C830A mutant, inhibited the phosphorylation and activation of p38α. Compared to the skin of wild-type mice, the skin of Itch-/- mice contained increased amounts of the mRNAs of proinflammatory cytokines, including tumor necrosis factor (TNF), interleukin-6 (IL-6), IL-1ß, IL-11, and IL-19. Inhibition of p38 or blocking the interaction between p38α and Tab1 with a cell-permeable peptide substantially attenuated skin inflammation in Itch-/- mice. These findings provide insight into how Itch-mediated regulatory mechanisms prevent chronic skin inflammation, which could be exploited therapeutically.

Multifaceted role of the ubiquitin ligase Itch in immune regulation.

The HECT-type E3 ligase Itch is increasingly being shown to have a vital role in immune regulation. Itch deficiency leads to deleterious inflammatory disorders both in mice and humans. By adding ubiquitin to the key signaling intermediates, Itch functions as a critical regulator of lymphocyte-cell activation, differentiation and immune tolerance. Also, Itch cooperates with deubiquitinating enzymes such as A20 and Cyld to terminate NF-κB signaling and prevent chronic inflammation. This review summarizes recent advances that highlight Itch's role in lymphocyte function and explores recent insights regarding its role as a regulator of inflammatory signaling.