Deubiquitinase USP4 suppresses antitumor immunity by inhibiting IRF3 activation and tumor cell-intrinsic interferon response in colorectal cancer.

Despite the approval of immune checkpoint blockade (ICB) therapy for various tumor types, its effectiveness is limited to only approximately 15% of patients with microsatellite instability-high (MSI-H) or mismatch repair deficiency (dMMR) colorectal cancer (CRC). Approximately 80%-85% of CRC patients have a microsatellite stability (MSS) phenotype, which features a rare T-cell infiltration. Thus, elucidating the mechanisms underlying resistance to ICB in patients with MSS CRC is imperative. In this study, we demonstrate that ubiquitin-specific peptidase 4 (USP4) is upregulated in MSS CRC tumors and negatively regulates the immune response against tumors in CRC. Additionally, USP4 represses the cellular interferon (IFN) response and antigen presentation and impairs PRR signaling-mediated cell death. Mechanistically, USP4 impedes the nuclear localization of interferon regulator Factor 3 (IRF3) by deubiquitinating the K63-polyubiquitin chain of TRAF6 and IRF3. Knockdown of USP4 enhances the infiltration of T cells in CRC tumors and overcomes ICB resistance in an MC38 syngeneic mouse model. Moreover, published datasets revealed that patients showing higher USP4 expression exhibited decreased responsiveness to anti-PD-L1 therapy. These findings highlight an essential role of USP4 in the suppression of antitumor immunity in CRC.

Technological Vanguard: the outstanding performance of the LTY-CNN model for the early prediction of epileptic seizures.

BACKGROUND: Epilepsy is a common neurological disorder that affects approximately 60 million people worldwide. Characterized by unpredictable neural electrical activity abnormalities, it results in seizures with varying intensity levels. Electroencephalography (EEG), as a crucial technology for monitoring and predicting epileptic seizures, plays an essential role in improving the quality of life for people with epilepsy. METHOD: This study introduces an innovative deep learning model, a lightweight triscale yielding convolutional neural network" (LTY-CNN), that is specifically designed for EEG signal analysis. The model integrates a parallel convolutional structure with a multihead attention mechanism to capture complex EEG signal features across multiple scales and enhance the efficiency achieved when processing time series data. The lightweight design of the LTY-CNN enables it to maintain high performance in environments with limited computational resources while preserving the interpretability and maintainability of the model. RESULTS: In tests conducted on the SWEC-ETHZ and CHB-MIT datasets, the LTY-CNN demonstrated outstanding performance. On the SWEC-ETHZ dataset, the LTY-CNN achieved an accuracy of 99.9%, an area under the receiver operating characteristic curve (AUROC) of 0.99, a sensitivity of 99.9%, and a specificity of 98.8%. Furthermore, on the CHB-MIT dataset, it recorded an accuracy of 99%, an AUROC of 0.932, a sensitivity of 99.1%, and a specificity of 93.2%. These results signify the remarkable ability of the LTY-CNN to distinguish between epileptic seizures and nonseizure events. Compared to other existing epilepsy detection classifiers, the LTY-CNN attained higher accuracy and sensitivity. CONCLUSION: The high accuracy and sensitivity of the LTY-CNN model demonstrate its significant potential for epilepsy management, particularly in terms of predicting and mitigating epileptic seizures. Its value in personalized treatments and widespread clinical applications reflects the broad prospects of deep learning in the health care sector. This also highlights the crucial role of technological innovation in enhancing the quality of life experienced by patients.

USP36 stabilizes nucleolar Snail1 to promote ribosome biogenesis and cancer cell survival upon ribotoxic stress.

Tumor growth requires elevated ribosome biogenesis. Targeting ribosomes is an important strategy for cancer therapy. The ribosome inhibitor, homoharringtonine (HHT), is used for the clinical treatment of leukemia, yet it is ineffective for the treatment of solid tumors, the reasons for which remain unclear. Here we show that Snail1, a key factor in the regulation of epithelial-to-mesenchymal transition, plays a pivotal role in cellular surveillance response upon ribotoxic stress. Mechanistically, ribotoxic stress activates the JNK-USP36 signaling to stabilize Snail1 in the nucleolus, which facilitates ribosome biogenesis and tumor cell survival. Furthermore, we show that HHT activates the JNK-USP36-Snail1 axis in solid tumor cells, but not in leukemia cells, resulting in solid tumor cell resistance to HHT. Importantly, a combination of HHT with the inhibition of the JNK-USP36-Snail1 axis synergistically inhibits solid tumor growth. Together, this study provides a rationale for targeting the JNK-USP36-Snail1 axis in ribosome inhibition-based solid tumor therapy.

Identification and validation of a novel stress granules-related prognostic model in colorectal cancer.

Aims: A growing body of evidence demonstrates that Stress granules (SGs), a non-membrane cytoplasmic compartments, are important to colorectal development and chemoresistance. However, the clinical and pathological significance of SGs in colorectal cancer (CRC) patients is unclear. The aim of this study is to propose a new prognostic model related to SGs for CRC on the basis of transcriptional expression. Main methods: Differentially expressed SGs-related genes (DESGGs) were identified in CRC patients from TCGA dataset by limma R package. The univariate and Multivariate Cox regression model was used to construct a SGs-related prognostic prediction gene signature (SGPPGS). The CIBERSORT algorithm was used to assess cellular immune components between the two different risk groups. The mRNA expression levels of the predictive signature from 3 partial response (PR) and 6 stable disease (SD) or progress disease (PD) after neoadjuvant therapy CRC patients' specimen were examined. Key findings: By screening and identification, SGPPGS comprised of four genes (CPT2, NRG1, GAP43, and CDKN2A) from DESGGs is established. Furthermore, we find that the risk score of SGPPGS is an independent prognostic factor to overall survival. Notably, the abundance of immune response inhibitory components in tumor tissues is upregulated in the group with a high-risk score of SGPPGS. Importantly, the risk score of SGPPGS is associated with the chemotherapy response in metastatic colorectal cancer. Significance: This study reveals the association between SGs related genes and CRC prognosis and provides a novel SGs related gene signature for CRC prognosis prediction.

Long non-coding RNA CCL14-AS suppresses invasiveness and lymph node metastasis of colorectal cancer cells by regulating MEP1A.

BACKGROUND: Long non-coding RNAs (lncRNAs) play important roles in the biology of colorectal cancer (CRC). There are several lncRNAs associated with invasion and metastasis have been characterized in CRC. However, studies focusing on the precise molecular mechanisms by which lncRNAs function in lymph node (LN) metastasis in CRC are still limited. METHODS: In this study, by analyzing TCGA dataset, we identified that AC244100.2 (termed CCL14-AS), a novel lncRNA enriched in the cytoplasm, was negatively correlated with LN metastasis and unfavorable prognosis of CRC. In situ hybridization was used to examine CCL14-AS expression in clinical CRC tissues. Various functional experiments including migration assay and wound-healing assay were used to investigate the effects of CCL14-AS on CRC cells migration. The nude mice popliteal lymph node metastasis model assay further confirmed the effects of CCL14-AS in vivo. RESULTS: CCL14-AS expression was significantly downregulated in CRC tissues compared to adjacent normal tissues. In addition, low CCL14-AS expression was correlated with advanced T classification, LN metastasis, distant metastasis, and shorter disease-free survival of CRC patients. Functionally, CCL14-AS overexpression inhibited the invasiveness of CRC cells in vitro and LN metastasis in nude mice. On the contrary, knockdown of CCL14-AS promoted the invasiveness and LN metastasis abilities of CRC cells. Mechanistically, CCL14-AS downregulated the expression of MEP1A via interacting with MEP1A mRNA and reduced its stability. Overexpression of MEP1A rescued the invasiveness and LN metastasis abilities in CCL14-AS-overexpressing CRC cells. Moreover, the expression levels of CCL14-AS was negatively correlated with that of MEP1A in CRC tissues. CONCLUSIONS: We identified a novel lncRNA, CCL14-AS, as a potential tumor suppressor in CRC. Our findings supported a model in which the CCL14-AS/MEP1A axis serves as critical regulator in CRC progression, suggesting a novel biomarker and therapeutic target in advanced CRC.

FBXL2 promotes E47 protein instability to inhibit breast cancer stemness and paclitaxel resistance.

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer with a high risk of metastasis and recurrence. Although chemotherapy has greatly improved the clinical outcome of TNBC patients, acquired drug resistance remains a huge challenge for TNBC treatment. Breast cancer stem cells (BCSCs) play a critical role in breast cancer development, metastasis, recurrence, and chemotherapy resistance. Thus, it is of great importance to decipher the underlying molecular mechanism of BCSCs regulation for TNBC drug resistance. In this study, we demonstrate that the F-box protein FBXL2 is a critical negative regulator of BCSCs stemness and that downregulation of FBXL2 plays a causal role in TNBC drug resistance. We show that expression levels of FBXL2 significantly influence CD44high/CD24low subpopulation and the mammosphere formation ability of TNBC cells. Ectopic expression of FBXL2 inhibits initiation of TNBC and overcomes paclitaxel resistance in vivo. In addition, activation of FBXL2 by nebivolol, a clinically used small-molecule inhibitor of the beta-1 receptor, markedly overcomes BCSCs-induced paclitaxel resistance. Mechanistically, we show that FBXL2 targets transcriptional factor E47 for polyubiquitin- and proteasome-mediated degradation, resulting in inhibition of BCSC stemness. Clinical analyses indicate that low expression of FBXL2 correlates with high expression of E47 as well as with high stemness features, and is associated with poor clinical outcomes of breast cancer patients. Taken together, these results highlight that the FBXL2-E47 axis plays a critical role in the regulation of BCSC stemness and paclitaxel resistance. Thus, targeting FBXL2 might be a potential therapeutic strategy for drug-resistant TNBC.

USP14 promotes tryptophan metabolism and immune suppression by stabilizing IDO1 in colorectal cancer.

Indoleamine 2,3 dioxygenase 1 (IDO1) is an attractive target for cancer immunotherapy. However, IDO1 inhibitors have shown disappointing therapeutic efficacy in clinical trials, mainly because of the activation of the aryl hydrocarbon receptor (AhR). Here, we show a post-transcriptional regulatory mechanism of IDO1 regulated by a proteasome-associated deubiquitinating enzyme, USP14, in colorectal cancer (CRC). Overexpression of USP14 promotes tryptophan metabolism and T-cell dysfunction by stabilizing the IDO1 protein. Knockdown of USP14 or pharmacological targeting of USP14 decreases IDO1 expression, reverses suppression of cytotoxic T cells, and increases responsiveness to anti-PD-1 in a MC38 syngeneic mouse model. Importantly, suppression of USP14 has no effects on AhR activation induced by the IDO1 inhibitor. These findings highlight a relevant role of USP14 in post-translational regulation of IDO1 and in the suppression of antitumor immunity, suggesting that inhibition of USP14 may represent a promising strategy for CRC immunotherapy.

FBXL2 counteracts Grp94 to destabilize EGFR and inhibit EGFR-driven NSCLC growth.

Abnormal activation of epidermal growth factor receptor (EGFR) drives non-small cell lung cancer (NSCLC) development. EGFR mutations-mediated resistance to tyrosine-kinase inhibitors (TKIs) is a major hurdle for NSCLC treatment. Here, we show that F-box protein FBXL2 targets EGFR and EGFR TKI-resistant mutants for proteasome-mediated degradation, resulting in suppression of EGFR-driven NSCLC growth. Reduced FBXL2 expression is associated with poor clinical outcomes of NSCLC patients. Furthermore, we show that glucose-regulated protein 94 (Grp94) protects EGFR from degradation via blockage of FBXL2 binding to EGFR. Moreover, we have identified nebivolol, a clinically used small molecule inhibitor, that can upregulate FBXL2 expression to inhibit EGFR-driven NSCLC growth. Nebivolol in combination with osimertinib or Grp94-inhibitor-1 exhibits strong inhibitory effects on osimertinib-resistant NSCLC. Together, this study demonstrates that the FBXL2-Grp94-EGFR axis plays a critical role in NSCLC development and suggests that targeting FBXL2-Grp94 to destabilize EGFR may represent a putative therapeutic strategy for TKI-resistant NSCLC.

Genetic characterization of Carbapenem-Resistant Escherichia coli from China, 2015-2017.

BACKGROUND: The molecular characteristics of carbapenem-resistant Escherichia coli (CREco) remain unclear. METHODS: We conducted a multi-center bacterial resistance monitoring project from 2015 to 2017.The minimum inhibitory concentrations ofCREco were determined bybroth microdilution method. The genome sequencing of CREcoisolates was performed, and single-nucleotide polymorphism (SNP) was analyzed. RESULTS: A total of 144CREcoisolatescollected from 10 cities in China were involved in this study. ST167 (n = 43) is the most popular type, followed by ST410(n = 14), ST131(n = 9). There were 102 (70.83%) CREco isolates that produced various NDMs, including NDM-1 (n = 16), NDM-4(n = 1), NDM-5(n = 79), NDM-6(n = 2) and NDM-9(n = 4). In addition, 15 isolates produced KPC-2, three isolates wereIMP-4 positive, and three isolates produced OXA-48. Genetic relatedness and phylogenetic analysis showed that isolates with the same ST had a high degree of homology. Some STs (including ST167, ST410, ST131, ST46, ST405 and ST617) exhibited a trend of outbreak. CONCLUSIONS: The majority of CREco belonged to ST167, followed by ST410 and ST131, and most of them carried various NDM-coding genes. The spread of high-risk clones of CREco has occurred in different regions of China.

E47 upregulates ΔNp63α to promote growth of squamous cell carcinoma.

Targeted therapy has greatly improved both survival and prognosis of cancer patients. However, while therapeutic treatment of adenocarcinoma has been advanced greatly, progress in treatment of squamous cell carcinoma (SCC) has been slow and ineffective. Therefore, it is of great importance to decipher mechanisms and identify new drug targets involved in squamous cell carcinoma development. In this study, we demonstrate that E47 plays the distinctive and opposite roles on cell proliferation in adenocarcinoma and squamous cell carcinoma. While E47 suppresses cell proliferation in adenocarcinoma cells, it functions as a oncoprotein to promote cell proliferation and tumor growth of squamous cell carcinoma. Mechanistically, we show that E47 can directly bind to the promoter and transactivate ΔNp63 gene expression in squamous cell carcinoma cells, resulting in upregulation of cyclins D1/E1 and downregulation of p21, and thereby promoting cell proliferation and tumor growth. We further show that expression of E2A (E12/E47) is positively correlated with p63 and that high expression of E2A is associated with poor outcomes in clinical samples of squamous cell carcinoma. These results highlight that the E47-ΔNp63α axis may be potential therapeutic targets for treatment of squamous cell carcinoma.

Noncanonical TGF-ß signaling leads to FBXO3-mediated degradation of ΔNp63α promoting breast cancer metastasis and poor clinical prognosis.

Transforming growth factor-ß (TGF-ß) signaling plays a critical role in promoting epithelial-to-mesenchymal transition (EMT), cell migration, invasion, and tumor metastasis. ΔNp63α, the major isoform of p63 protein expressed in epithelial cells, is a key transcriptional regulator of cell adhesion program and functions as a critical metastasis suppressor. It has been documented that the expression of ΔNp63α is tightly controlled by oncogenic signaling and is frequently reduced in advanced cancers. However, whether TGF-ß signaling regulates ΔNp63α expression in promoting metastasis is largely unclear. In this study, we demonstrate that activation of TGF-ß signaling leads to stabilization of E3 ubiquitin ligase FBXO3, which, in turn, targets ΔNp63α for proteasomal degradation in a Smad-independent but Erk-dependent manner. Knockdown of FBXO3 or restoration of ΔNp63α expression effectively rescues TGF-ß-induced EMT, cell motility, and tumor metastasis in vitro and in vivo. Furthermore, clinical analyses reveal a significant correlation among TGF-ß receptor I (TßRI), FBXO3, and p63 protein expression and that high expression of TßRI/FBXO3 and low expression of p63 are associated with poor recurrence-free survival (RFS). Together, these results demonstrate that FBXO3 facilitates ΔNp63α degradation to empower TGF-ß signaling in promoting tumor metastasis and that the TßRI-FBXO3-ΔNp63α axis is critically important in breast cancer development and clinical prognosis. This study suggests that FBXO3 may be a potential therapeutic target for advanced breast cancer treatment.

p53-R273H promotes cancer cell migration via upregulation of neuraminidase-1.

Accumulating evidence indicates that hotspot p53 mutants have gain-of-function in promoting cell migration and tumor metastasis. However, the molecular mechanisms are not completely understood. Here, we show that a hotspot mutation, p53-R273H, promotes non-small cell lung cancer (NSCLC) cell migration and upregulates the mRNA and protein expression of neuraminidase-1 (NEU1), a sialidase involved in cell proliferation, cell migration and tumorigenesis. Silencing of NEU1 leads to upregulation of integrin ß4 which significantly inhibits NSCLC cell migration induced by p53-R273H. Mechanistically, p53-R273H promotes NEU1 transcription via activation of AKT signaling. Importantly, NEU1 expression is upregulated in human NSCLC samples harboring mutant p53 and is associated with poor clinical outcome. Overall, this study highlights an important role of NEU1 in p53-R273H-induced NSCLC cell migration and provides a potential target for NSCLC diagnosis and treatment.

The Deubiquitinase USP4 Stabilizes Twist1 Protein to Promote Lung Cancer Cell Stemness.

Lung cancer stem cells (CSCs) play a pivotal role in tumor development, drug resistance, metastasis and recurrence of lung cancer. Thus, it is of great importance to study the mechanism by which CSCs are regulated. In this study, we demonstrate that the deubiquitinase USP4 is critically important in promoting lung cancer stemness. Silencing of USP4 leads to reduction of Oct4 and Sox2 expression, decreased CD133+ cell population and inhibition of tumorsphere formation. Conversely, ectopic expression of USP4 significantly enhances lung cancer cell stemness, which is effectively rescued by simultaneous silencing of Twist1. Mechanistically, we identified USP4 as a novel deubiquitinase of Twist1. USP4 binds to, deubiquitinates and stabilizes Twist1 protein. Furthermore, we show that USP4 expression is elevated in human lung cancer specimens and is positively correlated with Twist1 expression. High expression of USP4/Twist1 is associated with poor clinical outcomes of lung cancer patients. Together, this study highlights an important role for USP4 in lung cancer stemness and suggests USP4 as a potential target for lung cancer diagnosis and treatment.

Transcriptional suppression of AMPKα1 promotes breast cancer metastasis upon oncogene activation.

AMP-activated protein kinase (AMPK) functions as an energy sensor and is pivotal in maintaining cellular metabolic homeostasis. Numerous studies have shown that down-regulation of AMPK kinase activity or protein stability not only lead to abnormality of metabolism but also contribute to tumor development. However, whether transcription regulation of AMPK plays a critical role in cancer metastasis remains unknown. In this study, we demonstrate that AMPKα1 expression is down-regulated in advanced human breast cancer and is associated with poor clinical outcomes. Transcription of AMPKα1 is inhibited on activation of PI3K and HER2 through ΔNp63α. Ablation of AMPKα1 expression or inhibition of AMPK kinase activity leads to disruption of E-cadherin-mediated cell-cell adhesion in vitro and increased tumor metastasis in vivo. Furthermore, restoration of AMPKα1 expression significantly rescues PI3K/HER2-induced disruption of cell-cell adhesion, cell invasion, and cancer metastasis. Together, these results demonstrate that the transcription control is another layer of AMPK regulation and suggest a critical role for AMPK in regulating cell-cell adhesion and cancer metastasis.

Outcome and factors of patients with nosocomial meningitis by multi-drug-resistant Gram-negative bacteria in a tertiary hospital in China: a retrospective study.

Background: Few data are available on the risk factors involved in nosocomial meningitis from multi-drug-resistant Gram-negative bacteria (MDR-GNB). Our aim was to identify the risk factors of prognosis for MDR-GNB nosocomial meningitis.Methods: Retrospective study of patients undergoing neurosurgery and with positive cerebrospinal fluid culture results post operation between January 2012 and January 2017 in a tertiary hospital in China.Results: In total, 3533 patients were screened. Forty patients with meningitis and completed data were included and divided into two groups, 29 who survived in the successful group (SG) and 11 who died in the failed group (FG). Statistically significant different factors involved in treating successful and failed were pathogen types, highest body temperature in the first 24h of symptoms, CSF glucose content and meropenem susceptibility (for Acinetobacter baumannii). The most common pathogen in the failed ones is Acinetobacter baumannii with meropenem MIC ≥ 16mg/L.Conclusions: Treatment of MDR-GNB nosocomial meningitis is more likely to fail in patients with severe condition when symptoms occur and infected by Acinetobacter baumannii. Researches with larger population are needed to find more factors to improve patient outcome.

Clinical value of (1,3)-ß-D-glucan, mannan, antimannan IgG and IgM antibodies in diagnosis of invasive candidiasis.

Diagnosis of invasive candidiasis (IC) is still challenging due to absence of specific clinical signs and symptoms. In this study we investigate the clinical value of (1,3)-ß-D-glucan (BDG), mannan (MN), antimannan immunoglobulin G (AM-IgG), and antimannan immunoglobulin M (AM-IgM) assay in diagnosis of IC. During 2016 to 2018 serum samples from 71 patients with IC and 185 patients without IC were collected. Serum samples from 41 patients with bacteremia were also enrolled as additional control. Significant differences in mean serum biomarkers levels between IC and control group were observed. At low cutoff threshold the sensitivity and specificity of BDG (70 pg/ml), MN (50 pg/ml), AM-IgG (80 AU/ml), and AM-IgM (80 AU/ml) assay were 64.8% and 90.8%, 64.8 and 89.2%,74.6% and 87.0%, 57.7% and 60.0%, respectively. Combined use of BDG/MN, BDG/AM-IgG and MN/AM-IgG improved the sensitivity and specificity to 85.9% and 81.1%, 85.9% and 80.0%, 81.7% and 81.6%, respectively. The combination of BDG/MN, BDG/AM-IgG, or MN/AM-IgG may provide an encouraging approach for diagnosis of IC.

p53 and p73 Regulate Apoptosis but Not Cell-Cycle Progression in Mouse Embryonic Stem Cells upon DNA Damage and Differentiation.

Embryonic stem cells (ESCs) are fast proliferating cells capable of differentiating into all somatic cell types. In somatic cells, it is well documented that p53 is rapidly activated upon DNA damage to arrest the cell cycle and induce apoptosis. In mouse ESCs, p53 can also be functionally activated, but the precise biological consequences are not well characterized. Here, we demonstrated that doxorubicin treatment initially led to cell-cycle arrest at G2/M in ESCs, followed by the occurrence of massive apoptosis. Neither p53 nor its target gene p73 was required for G2/M arrest. Instead, p53 and p73 were fully responsible for apoptosis. p53 and p73 were also required for differentiation-induced apoptosis in mouse ESCs. In addition, doxorubicin treatment induced the expression of retinoblastoma protein in a p53-dependent manner. Therefore, both p53 and p73 are critical in apoptosis induced by DNA damage and differentiation.