UBE3A activates the NOTCH pathway and promotes esophageal cancer progression by degradation of ZNF185

MRPS16 promotes lung adenocarcinoma growth via the PI3K/AKT/Frataxin signalling axis

Although MRPS16 is involved in cancer development, its mechanisms in developing LAUD remain unclear. Herein, qRT-PCR, WB and IHC were utilized for evaluating MRPS16 expression levels, while functional assays besides animal experiments were performed to measure MRPS16 effect on LAUD progression. Using WB, the MRPS16 effect on PI3K/AKT/Frataxin signalling pathway was tested. According to our study, MRPS16 was upregulated in LAUD and was correlated to the advanced TNM stage as well as poor clinical outcomes, which represent an independent prognostic factor. Based on functional assays, MRPS16 is involved in promoting LAUD growth, migration and invasion, which was validated further in subsequent analyses through PI3K/AKT/Frataxin pathway activation. Moreover, MRPS16-knockdown-mediated Frataxin overexpression was shown to restore the reduction in tumour cells proliferation, migration and invasion. Our results revealed that MRPS16 caused an aggressive phenotype to LAUD and was a poor prognosticator; thus, targeting MRPS16 may be effectual in LAUD treatment.

Excavation of gene markers associated with pancreatic ductal adenocarcinoma based on interrelationships of gene expression

Pancreatic ductal adenocarcinoma (PDAC) accounts for 95% of all pancreatic cancer cases, posing grave challenges to its diagnosis and treatment. Timely diagnosis is pivotal for improving patient survival, necessitating the discovery of precise biomarkers. An innovative approach was introduced to identify gene markers for precision PDAC detection. The core idea of our method is to discover gene pairs that display consistent opposite relative expression and differential co-expression patterns between PDAC and normal samples. Reversal gene pair analysis and differential partial correlation analysis were performed to determine reversal differential partial correlation (RDC) gene pairs. Using incremental feature selection, the authors refined the selected gene set and constructed a machine-learning model for PDAC recognition. As a result, the approach identified 10 RDC gene pairs. And the model could achieve a remarkable accuracy of 96.1% during cross-validation, surpassing gene expression-based models. The experiment on independent validation data confirmed the model's performance. Enrichment analysis revealed the involvement of these genes in essential biological processes and shed light on their potential roles in PDAC pathogenesis. Overall, the findings highlight the potential of these 10 RDC gene pairs as effective diagnostic markers for early PDAC detection, bringing hope for improving patient prognosis and survival.

Tumor-associated macrophage-derived exosomes LINC01592 induce the immune escape of esophageal cancer by decreasing MHC-I surface expression

BACKGROUND

TAMs (tumor-associated macrophages) infiltration promotes the progression of esophageal cancer (EC). However, the underlying mechanisms remain unclear.

METHODS

Abnormal expression of LINC01592 from EC microarrays of the TCGA database was analyzed. LINC01592 expression level was validated in both EC cell lines and tissues. Stable LINC01592 knockdown and overexpression of EC cell lines were established. In vitro and in vivo trials were conducted to test the impact of LINC01592 knockdown and overexpression on EC cells. RNA binding protein immunoprecipitation (RIP), RNA pulldown assays, and Immunofluorescence (IF) were used to verify the combination of E2F6 and LINC01592. The combination of E2F6 and NBR1 was verified through the utilization of ChIP and dual luciferase reporter assays.

RESULTS

LINC01592 is carried and transferred by exosomes secreted by M2-TAMs to tumor cells. The molecular mechanism underlying the promotion of NBR1 transcription involves the direct binding of LINC01592 to E2F6, which facilitates the nuclear entry of E2F6. The collaborative action of LINC01592 and E2F6 results in improved NBR1 transcription. The elevation of NBR1 binding to the ubiquitinated protein MHC-I via the ubiquitin domain caused a higher degradation of MHC-I in autophagolysosomes and a reduction in MHC-I expression on the exterior of cancerous cell. Consequently, this caused cancerous cells to escape from CD8+ CTL immune attack. The tumor-promoting impacts of LINC01592, as well as the growth of M2-type macrophage-driven tumors, were significantly suppressed by the interruption of E2F6/NBR1/MHC-I signaling through the effect of siRNA or the corresponding antibody blockade. Significantly, the suppression of LINC01592 resulted in an upregulation of MHC-I expression on the tumor cell membrane, thereby enhancing the efficacy of CD8+ T cell reinfusion therapy.

CONCLUSIONS

The investigation conducted has revealed a significant molecular interaction between TAMs and EC via the LINC01592/E2F6/NBR1/MHC-I axis, which facilitates the progression of malignant tumors. This suggests that a therapeutic intervention targeting this axis may hold promise for the treatment of the disease.

Construction of HBV-HCC prognostic model and immune characteristics based on potential genes mining through protein interaction networks

OBJECTIVE

To search for human protein-coding genes related to hepatocellular carcinoma (HCC) in the context of hepatitis B virus (HBV) infection, and perform prognosis risk assessment.

METHODS

Genes related to HBV-HCC were selected through literature screening and protein-protein interaction (PPI) network database analysis. Prognosis potential genes (PPGs) were identified using Cox regression analysis. Patients were divided into high-risk and low-risk groups based on PPGs, and risk scores were calculated. Kaplan-Meier plots were used to analyze overall survival rates, and the results were predicted based on clinicopathological variables. Association analysis was also conducted with immune infiltration, immune therapy, and drug sensitivity. Experimental verification of the expression of PPGs was done in patient liver cancer tissue and normal liver tissue adjacent to tumors.

RESULTS

The use of a prognosis potential genes risk assessment model can reliably predict the prognosis risk of patients, demonstrating strong predictive ability. Kaplan-Meier analysis showed that the overall survival rate of the low-risk group was significantly higher than that of the high-risk group. There were significant differences between the two subgroups in terms of immune infiltration and IC50 association analysis. Experimental verification revealed that CYP2C19, FLNC, and HNRNPC were highly expressed in liver cancer tissue, while UBE3A was expressed at a lower level.

CONCLUSION

PPGs can be used to predict the prognosis risk of HBV-HCC patients and play an important role in the diagnosis and treatment of liver cancer. They also reveal their potential role in the tumor immune microenvironment, clinical-pathological characteristics, and prognosis.

UBE3A and MCM6 synergistically regulate the proliferation and migration of lung adenocarcinoma cells

Lung cancer is a leading cause of mortality worldwide and shows substantial clinical and biomolecular heterogeneity. Currently, specific therapeutic strategies are lacking, so effective drug targets are urgently needed. E6AP/UBE3A is a multifaceted ubiquitin ligase that controls various signaling pathways implicated in neurological diseases and various cancers; however, its role in lung cancer is incompletely understood. Here, MCM6 was identified as an interacting partner of E6AP using the yeast two-hybrid assay. MCM2 and MCM4 were then shown to interact with E6AP. E6AP knockout enhanced the ubiquitination of MCM2/4/6, suggesting that E6AP was not the E3 ubiquitin ligase for these three MCM proteins. Ablation of E6AP inhibited proliferation and migration, but had no significant effect on apoptosis in A549 and H1975 cells, and proliferation and migration inhibition was also observed in MCM6 knockdown cells. Furthermore, ablation of MCM6 and E6AP synergistically suppressed the proliferation and migration of A549 and H1975 cells. To verify the above findings in vivo, we established tumor models in nude mice and identified that the tumorigenicity of human lung adenocarcinoma (LUAD) cells was synergistically regulated by MCM6 and E6AP. Moreover, the expression levels of MCM6 and E6AP were higher in LUAD tissues than in adjacent tissues. Furthermore, the expression levels of MCM6 and E6AP were positively correlated in human LUAD samples. Thus, our study suggests that the interaction of E6AP and MCM proteins plays an important role in the progression of LUAD, which might offer potential therapeutic targets for cancer treatment.

Effects of UBE3A on the insulin resistance in polycystic ovary syndrome through the ubiquitination of AMPK

BACKGROUND

Polycystic ovary syndrome (PCOS) is a reproductive hormonal abnormality and a metabolic disorder, which is frequently associated with insulin resistance (IR). We aim to investigate the potential therapeutic effects of Ubiquitin-protein ligase E3A (UBE3A) on IR in the PCOS rats via Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) activation.

METHODS

The PCOS and IR rats model was established by dehydroepiandrosterone (DHEA) and high fat diet (HFD) treatment, and the fat rate, glucose tolerance and insulin tolerance were measured. The IR rats numbers were calculated. Besides, the mRNA levels of glucose transporter 4 (GLUT4) and UBE3A were detected by RT-qPCR. Furthermore, the relationship between was demonstrated by co-IP assay. The phosphorylation and ubiquitination of AMPK were analyzed by western blot.

RESULTS

UBE3A was up-regulated in the PCOS rats. UBE3A knockdown significantly decreased the fat rate, glucose tolerance and insulin tolerance in the PCOS and IR rats. Additionally, the GLUT4 levels were significantly increased in PCOS + IR rats. Besides, after UBE3A knockdown, the IR rats were decreased, the p-IRS1 and p-AKT levels were significantly up-regulated. Furthermore, UBE3A knockdown enhanced phosphorylation of AMPK through decreasing the ubiquitination of AMPK. AMPK knockdown reversed the role of UBE3A knockdown in the PCOS + IR rats.

CONCLUSIONS

UBE3A knockdown inhibited the IR in PCOS rats through targeting AMPK. Our study indicated that UBE3A might become a potential biological target for the clinical treatment of PCOS.

MicroRNA-375 restrains the progression of lung squamous cell carcinoma by modulating the ERK pathway via UBE3A-mediated DUSP1 degradation

MiRNA-375 has been reported to play critical roles in a variety of cancers. To unravel its biological roles, especially its specific mechanisms of action in lung squamous cell carcinoma (LUSC), LUSC tissue microarrays and miRNAscope were performed to identify the miR-375 expression. Associations with clinicopathologic features, survival, and the prognostic value of miR-375 in LUSC were clarified in a retrospective study of 90 pairs of LUSC tissues. In vitro and in vivo gain- and loss-of-function assays were conducted to validate the effects and mechanism of miR-375 in LUSC. The mechanism responsible for interactions was verified by dual-luciferase reporter gene assay, immunoprecipitation (IP) analysis, immunofluorescence (IF) assay and ubiquitination assay. We found that miR-375 had higher expression in noncancerous adjacent tissues than in LUSC tissues. Clinicopathologic analyses showed that miR-375 expression was correlated with pathologic stage and was an independent predictor of overall survival (OS) for LUSC. MiR-375, as a tumor inhibitor, inhibited proliferation and metastasis while promoting apoptosis of LUSC cells. Mechanistic research indicated that miR-375 targeted ubiquitin-protein ligase E3A (UBE3A), which in turn promoted the activity of the ERK signaling pathway via ubiquitin-mediated dual-specificity protein phosphatase 1 (DUSP1) degradation. Collectively, we propose a novel mechanism of tumorigenesis and metastasis of LUSC via the miR-375/UBE3A/DUSP1/ERK axis, which could potentially facilitate new strategies for the treatment of LUSC.

Targeting immune cell types of tumor microenvironment to overcome resistance to PD-1/PD-L1 blockade in lung cancer

Lung cancer is the common malignant tumor with the highest mortality rate. Lung cancer patients have achieved benefits from immunotherapy, including immune checkpoint inhibitors (ICIs) therapy. Unfortunately, cancer patients acquire adaptive immune resistance, leading to poor prognosis. Tumor microenvironment (TME) has been demonstrated to play a critical role in participating in acquired adaptive immune resistance. TME is associated with molecular heterogeneity of immunotherapy efficacy in lung cancer. In this article, we discuss how immune cell types of TME are correlated with immunotherapy in lung cancer. Moreover, we describe the efficacy of immunotherapy in driven gene mutations in lung cancer, including KRAS, TP53, EGFR, ALK, ROS1, KEAP1, ZFHX3, PTCH1, PAK7, UBE3A, TNF-α, NOTCH, LRP1B, FBXW7, and STK11. We also emphasize that modulation of immune cell types of TME could be a promising strategy for improving adaptive immune resistance in lung cancer.

RHBDL2 promotes the proliferation, migration, and invasion of pancreatic cancer by stabilizing the N1ICD via the OTUD7B and activating the Notch signaling pathway

Pancreatic cancer (PC) is one of the most malignant types of cancer, and is characterized by early metastasis, limited response to chemotherapeutics, and poor prognosis. Therefore, there is an urgent need to explore new therapeutic strategies for PC treatment. Human rhomboid-like 2 (RHBDL2) is differentially expressed in cervical and breast cancer. However, the correlation between RHBDL2 and PC remains unclear. We found that RHBDL2 is highly expressed in human PC cells and tissues and is significantly associated with distant metastasis and poor survival of patients with PC. Gain- and loss-of-function assays indicated that RHBDL2 could accelerate PC cell proliferation and mobility in vitro and in vivo. The RNA-Seq results suggest that RHBDL2 may be involved in the activation of Notch signaling pathway. IMR-1 could restore the proliferation and metastatic capacity of PC cells mediated by RHBDL2. RHBDL2 interacted with and cleaved Notch1, resulting in the release of N1ICD. RHBDL2 decreased the ubiquitination level of N1ICD and collaborated with Ovarian tumor domain-containing 7B (OTUD7B) to stabilize N1ICD via the ubiquitin-proteasome pathway. RHBDL2 facilitated PC cell proliferation and mobility by stabilizing the N1ICD via the OTUD7B and activating the Notch signaling pathway. Thus, targeting this novel pathway may be a potential therapeutic strategy for PC.

[Inhibition of the Notch1/Jagged1 pathway promotes homing of bone mesenchymal stem cells to improve asthma in rats]

OBJECTIVE

To explore the association of the Notch1/Jagged1 pathway with the homing of mesenchymal stem cells (BMSCs) to regulate Th1/Th2 drift in asthma.

METHODS

Twenty SD rats were randomly divided into normal control group, model group, BMSC transplantation group, and BMSC+Notch inhibitor group. Ovalbumin sensitization was used to establish rat models of asthma, and BMSCs were transplanted via the tail vein. The pathology of the lung tissue was examined with HE staining, and the contents of interleukin (IL)-5, IL-13, and interferon-γ (IFN-γ) in lung tissue homogenate were determined with enzyme-linked immunosorbent assay. The expressions of Notch1 and Jagged1 mRNA were detected with RT-PCR, and CXCR4 expression in the bronchial epithelial cells was examined using immunofluorescence staining; Western blotting was used to detect the protein expressions of T-bet, GATA-3, Notch1, and Jagged1 in the lung tissue.

RESULTS

Compared with those in the control group, the expressions of IFN-γ and T-bet proteins decreased significantly and the pulmonary expressions of IL-5, IL-13, and GATA-3 proteins as well as Notch1 and Jagged1 mRNA and protein expressions all increased significantly in the model group (P < 0.05 or 0.01). Compared with those in the model group, CXCR4, IFN-γ, and T-bet protein expressions in BMSC group and BMSCs+Notch inhibitor group all increased significantly, and Notch1 and Jagged1 protein expressions in BMSCs group and IL-5, IL-13, Notch1, and Jagged1 mRNA and protein expressions in BMSCs + Notch inhibitor group all decreased significantly (P < 0.05 or 0.01). The expressions of CXCR4 and IFN-γ were significantly higher and the expressions of IL-13 and Notch1 mRNA were significantly lower in BMSCs+Notch inhibitor group than in BMSC group (P < 0.05).

CONCLUSION

In asthmatic rats, the homing of the BMSCs to the lung tissue has a regulatory effect on Th1/Th2 drift, and the Notch1/Jagged1 pathway may participate in the homing of the BMSCs.