Silencing IKBKE inhibits the migration and invasion of glioblastoma by promoting Snail1 degradation

PURPOSE

Glioblastoma multiforme (GBM) is one of the most common malignant brain tumors in adults and has high mortality and relapse rates. Over the past few years, great advances have been made in the diagnosis and treatment of GBM, but unfortunately, the five-year overall survival rate of GBM patients is approximately 5.1%. Inhibitor of nuclear factor kappa-B kinase subunit epsilon (IKBKE) is a major oncogenic protein in tumors and can promote evil development of GBM. Snail1, a key inducer of the epithelial-mesenchymal transition (EMT) transcription factor, is subjected to ubiquitination and degradation, but the mechanism by which Snail1 is stabilized in tumors remains unclear. Our study aimed to investigate the mechanism of IKBKE regulating Snail1 in GBM.

METHODS

First, we analyzed the correlation between the expression of IKBKE and the tumor grade and prognosis through public databases and laboratory specimen libraries. Second, immunohistochemistry (IHC) and western blot were used to detect the correlation between IKBKE and Snail expression in glioma samples and cell lines. Western blot and immunofluorescence (IF) experiments were used to detect the quality and distribution of IKBKE and Snail1 proteins. Third, In situ animal model of intracranial glioma to detect the regulatory effect of IKBKE on intracranial tumors.

RESULTS

In this study, Our study reveals a new connection between IKBKE and Snail1, where IKBKE can directly bind to Snail1, translocate Snail1 into the nucleus from the cytoplasm. Downregulation of IKBKE results in Snail1 destabilization and impairs the tumor cell migration and invasion capabilities.

CONCLUSION

Our studies suggest that the IKBKE-Snail1 axis may serve as a potential therapeutic target for GBM treatment.

[Vascular endothelial growth factor promotes cancer stemness of triple-negative breast cancer via MAPK/ERK pathway]

OBJECTIVE

To investigate the role of vascular endothelial growth factor (VEGF) in regulating triple-negative breast cancer (TNBC) stem cells and the possible pathways involved in this regulatory mechanism.

METHODS

The Oncomine database, UALCAN database and Human Protein Atlas (HPA) database were used to analyze the expression of VEGF in breast cancer and its association with the molecular subtypes and prognosis of breast cancer. Sphere formation assay was carried out to examine the effects of hVEGF₁₆₅ on sphere formation ability of TNBC MDA-MB-231 cell line; Western blotting and RT-qPCR were performed to detect the expression of the tumor stem cell markers including CD44, c-Myc, Nanog, and ALDH1 and the activation of the related pathways.

RESULTS

Data from the online databases all showed a significant increase of VEGF expression in breast cancer tissues than in the adjacent tissues (P < 0.0001), and its expression level was associated with the molecular subtypes of breast cancer. Specifically, the expression of VEGF was markedly higher in TNBC than in other subtypes of breast cancer. Survival analysis showed that breast cancer patients with a high VEGF expression had a significantly shortened overall survival (P < 0.0001). In the cell experiments, the sphere formation ability of MDA-MB-231 cells was significantly enhanced after treatment with hVEGF₁₆₅ (P=0.0029). Compared with the monolayer cells, MDA-MB-231 spheres showed significantly increased expressions of VEGF, NRP-1, CD44, Nanog and c-Myc. Treatment with hVEGF₁₆₅ resulted in significant time-dependent up-regulation of the expressions of CD44, c-Myc, Nanog and ALDH1 and down-regulation of CD24 expression in the cells. The results of Western blotting demonstrated that treatment with hVEGF₁₆₅ caused significant activation of the ERK/MAPK pathway in MDA-MB-231 cells.

CONCLUSION

VEGF promotes cancer stemness of triple-negative breast cancer possibly through the ERK/MAPK pathway.

[Application of Hydrashift 2/4 daratumumab assay in eliminating interference of daratumumab on serum immunofixation electrophoresis]

Objective: To investigate the interference of daratumumab on immunofixation electrophoresis after treating plasma cell diseases and methods to eliminate the interference. Methods: Serum samples of eight patients with plasma cell diseases treated with daratumumab in Peking University People's Hospital from April 2020 to March 2021 were collected for standard immunofixation electrophoresis and Hydrashift 2/4 daratumumab assay. Results: After treatment, 81.3% (13/16) of the samples showed drug-induced monoclonal antibodies (IgG-κ) . The samples without drug-induced monoclonal bands were related to individual differences, administration intervals, and immunoglobulin levels. Among the samples with IgG-κ monoclonal bands, 76.9% (10/13) could be directly identified as endogenous or exogenous monoclonal bands by immunofixation electrophoresis, and the others (3/13) could be identified by Hydrashift 2/4 daratumumab assay. Conclusion: Hydrashift 2/4 daratumumab assay can remove the band of daratumumab on the immunofixation electrophoresis and help with efficacy evaluation.

[Validation of a contact-free sleep apnea monitor in adults with obstructive sleep apnea]

Objective: To evaluate the diagnostic value of a contact-free sleep apnea monitor in Chinese adults with obstructive sleep apnea (OSA). Methods: One hundred and ninety-eight participants with snoring were recruited between July 2018 and May 2019 in Sleep Center of Peking University People's Hospital, using nocturnal polysomnography (PSG) and contact-free sleep apnea monitor simultaneously. We evaluated the difference between respiratory event index (REI) generated by contact-free sleep apnea monitor and PSG-Apnea-Hypopnea Index (AHI). We calculated the sensitivity and specificity of OSA diagnosis using the contact-free sleep apnea monitor by hypothesis testing for means, Pearson correlation coefficient and Bland-Altman plots. Then, we used the receiver operating characteristic (ROC) curve to find out the best cut-off of OSA diagnosis. Results: PSG-AHI and the REI of contact-free sleep apnea monitor showed no statistically significant difference [15.9 (4.7, 40.2) vs. 16.2 (6.1, 40.0), P=0.381], and they were significantly correlated (r=0.914, P<0.05), with mean difference of -0.06 (95%CI:-18.44, 18.31). The ROC curve showed that if REI ≥5 events/h was used as diagnostic criteria, the sensitivity and specificity of diagnosing OSA were 91.2% and 58.0%, respectively. The sensitivity and specificity of the contact-free sleep apnea monitor REI≥13.3 in diagnosing moderate and severe OSA were 90.1% and 71.1%, respectively. Conclusion: The REI obtained from the contact-free sleep apnea monitor showed a good agreement with the PSG-AHI, and therefore, the contact-free sleep apnea monitor can be used for the screening of patients with moderate and severe OSA.

[Pulmonary mucormycosis after lung transplantation:3 cases report with literature review]

Objective: To report the risk factors, clinical characteristics and treatment courses of pulmonary mucormycosis after lung transplantation(LT). Methods: We included 3 cases with pulmonary mucormycosis after LT from March 2017 to July 2020 in the centre for lung transplantation of China-Japan Friendship Hospital. Twelve cases from Chinese and English literature from China National Knowledge Infrastructure (CNKI), China Biomedical Literature Service System and Pubmed Database from March 1980 to July 2020 were added. The risk factors, clinical characteristics and treatment courses of all cases were summarized and analyzed. Results: Pulmonary mucormycosis occurred in 1.06% (3/284) in our centre. A total of 15 cases with 12 cases from literature included 10 males and 5 females with a mean age of(47±20)years. Thirteen cases occurred after LT, and 2 cases occurred after heart-lung transplantation (HLT). Nine probable cases were diagnosed by positive isolation of the pathogen from bronchoalveolar lavage fluid or sputum. Three proven cases were diagnosed by transbronchial lung biopsy. Meanwhile, the other 3 proven cases diagnosed by CT-guided percutaneous lung biopsy, autopsy and surgical operation respectively. Ten cases (66.7%) were diagnosed with pulmonary mucormycosis within 90 days after lung transplantation. The mortality was as high as 46.67% (7/15), but if it occurred within 90 days, the mortality reached 70% (7/10). The average interval between transplantation and positive isolation of the pathogen was 112.3 (5-378) days. Conclusions: The clinical and radiographic features of pulmonary mucormycosis after LT were nonspecific. It had a high mortality, especially in those occurred within 90 days after LT. The combination of antifungal therapy and surgical resection may contribute to a better outcome of the disease.

[Study on mining of signals of adverse drug reactions of entecavir and tenofovir disoproxil based on the US FAERS database]

Objective: To mine the signals of adverse drug reaction (ADR) of entecavir and tenofovir by using the US FDA Adverse Event Reporting System (FAERS) database, so as to provide reference for the safe clinical use of these two drugs. Methods: Reporting odds ratio (ROR) and proportion of report ratio (PRR) method were used to conduct data mining on the 26 quarterly reports of the US Food and Drug Administration Adverse Event Reporting System (FAERS) database between the fourth quarter of 2012 to the first quarter of 2019. The ADR descriptive terminology in the report were standardized by using the World Health Organization Adverse Reaction Terminology (System-Organ Class). ROR and PRR methods common signals were screened. Results: 104 and 187 signals of ADR of entecavir and tenofovir dipivoxil were obtained by ROR and PRR methods. The main screened system-organ classes affected by signals of ADR of entecavir were systemic damage, hepatobiliary system damage, and urinary system damage. The main screened system-organ classes affected by signals of ADR of tenofovir were urinary system damage, skeletal and musculoskeletal system damage, and metabolic and nutritional disorders. Conclusion: The mining signals of adverse drug reaction of entecavir and tenofovir dipivoxil indicate that these two drugs can cause female reproductive system damage, fetal abnormalities, neonatal and infant abnormalities, and male reproductive system damage. However, in addition to the above-mentioned ADR, the ADR instruction manual excludes entecavir and tenofovir dipivoxil primarily for respiratory and visual system damage, and the tenofovir disoproxil primarily for skin and appendage damage, and hearing and vestibular function damage. Therefore, in clinical medication management, it is suggested to pay close attention to the choice of drugs for special population infected with HBV, monitor possible ADR during medication course, and provide pharmacological monitoring to achieve personalized medication.

Interrupting TGF-β1/CCN2/integrin-α5β1 signaling alleviates high mechanical-stress caused chondrocyte fibrosis

OBJECTIVE

Mechanical-stress has been reported to trigger cartilage fibrosis, in which transforming growth factor (TGF)-β and connective tissue growth factor (CCN2) are involved. However, the function of integrin-α5β1, a cytomembrane receptor, on mechanical-stress related fibrosis has not yet been elucidated. This study aims to reveal the interaction of TGF-β1/CCN2/integrin-α5β1 in the mechanical-stress induced chondrocyte (CH) fibrosis.

PATIENTS AND METHODS

We used different levels (5% and 10%) of cyclic tension simulation (CTS) to stretch CHs and observed the gene expression of TGF-β1/CCN2/integrin-α5β1 as well as the fibrous related genes containing collagen I/II/III, Runx2, MMP13, and ADAMTS-5 by real-time polymerase chain reaction (RT-PCR) or immunofluorescence. We used the siRNA or the corresponding antagonist of TGF-β1, CCN2, integrin-α5β1 during the CTS to clear the effect of them in the fibrosis progress. In addition, to verify the crosstalk between TGF-β1, CCN2, and integrin-α5β1, we used the recombinant human (rh)-TGF-β1 and CCN2 to culture CHs without CST.

RESULTS

24 hours-10% CTS was sufficient to induce a decrease of collagen II and increase the collagen I/III, Runx2, MMP13, and ADAMTS-5 gene expression. Under CTS, TGF-β1 silencing resulted in a decline of CCN2, integrin-α5β1, and alleviated the CHs fibrosis. Apart from this, blocking CCN2 or integrin-α5β1 expression also contributed to the suppression of 10% CTS induced CHs fibrosis. Meanwhile, the exogenic protein supplement raised the cellular TGF-β1 or CCN2 expression and increased the integrin-α5β1 mRNA level. However, the downregulation of TGF-β1 or CCN2 did not affect integrin-α5β1 expression, whether the CTS exited or not.

CONCLUSIONS

High mechanical-stress induces CHs fibrosis via the activation of TGF-β1/CCN2/integrin-α5β1 signaling, and interrupting the TGF-β1, CCN2, or integrin-α5β1 expression can alleviate the fibrous process.

[An optimized protocol of meniscus cell extraction for single-cell RNA sequencing]

OBJECTIVE

To optimize the protocol of meniscus cell extraction to enhance the efficiency of cell suspension preparation and maintain a high cell viability for single-cell RNA sequencing.

METHODS

We compared the efficiency of the routine cell extraction methods (short-time digestion and long-time digestion) and the optimized protocol for obtaining meniscus cell suspensions by evaluating the cell number obtained and the cell viability. Single-cell RNA sequencing datasets were analyzed to evaluate the stability of the cell suspension prepared using the optimized protocol. The reliability of the optimized protocol was assessed by comparing the single-cell RNA sequencing dataset obtained by the optimized protocol with published single-cell RNA sequencing datasets of the meniscus.

RESULTS

The optimized protocol harvested a greater number of cells (over 1×10⁵) than the routine protocols. The cell suspension prepared with the optimized protocol showed a cell viability higher than 80%, the highest among the 3 methods. Analysis of single-cell RNA sequencing datasets showed that the ratio of the mitochondrial genes was below 20% in over 80% of the cells. CD34⁺ cells, MCAM⁺ cells and COL1A1⁺ cells were identified in the datasets. Comparison with the publish datasets showed that the optimized protocol was capable of harvesting COL3A1⁺, COL1A1⁺, MYLK⁺, BMP2⁺, CD93⁺ and CDK1⁺ cells.

CONCLUSION

Single-cell suspension prepared from the meniscus can be stably obtained using the optimized protocol for single-cell RNA sequencing using the 10× Genomics platform.

[Efficacy of extracorporeal membrane oxygenation in patients with complex high risk coronary artery disease undergoing percutaneous coronary intervention]

Objective: To explore the safety and efficacy of venous-arterial extracorporeal membrane oxygenation (VA-ECMO) in complex high-risk and indicated patients (CHIP). Methods: This is a single-center retrospective study. Patients who underwent percutaneous coronary intervention (PCI) supported by VA-ECMO in the Second Hospital of Jilin University from June 2018 to January 2020 were enrolled. General clinical data, laboratory examination results, PCI and ECMO process, postoperative complications and prognosis were collected through the electronic medical record system. The endpoint of the study was major adverse cardiovascular events (MACE), defined as complex events including cardiac death, recurrent myocardial infarction, heart failure and malignant arrhythmia. All patients were followed up for 12 months after discharge. Kaplan-Meier method was used for survival analysis. Results: A total of 31 patients, aged (64.6±10.1) years, including 19 males were included. All patients were treated with VA-ECMO before PCI. The ProGlide vascular suture device was embedded by local anesthesia to quickly establish circulation. There were 9 (29.0%) patients with ST-segment elevation myocardial infarction, 10 (32.3%) patients with non-ST-segment elevation myocardial infarction and 12 (38.7%) patients with unstable angina. The number of stents implanted during the operation were 2.8±1.8. The VA-ECMO weaning time was 24.0 (2.0, 88.5) hours. Compared with the results of pre-operation, the patient's postoperative left ventricular ejection fraction was significantly improved (49% (42%, 55%) vs. 43% (35%, 52%), P<0.01], hemoglobin and platelet count levels decreased, the level of creatinine and urea nitrogen was increased (P<0.05). Within 24 hours after operation, hemoglobin decreased>20 g/L was observed in 18 cases (58.1%), puncture site bleeding was found in 2 cases (6.5%), pseudoaneurysm occurred in 1 case (3.2%) and postoperative cerebral infarction occurred in 1 case (3.2%). There were no deaths during the operation, 2 patients died during hospitalization. All discharged patients were followed up for 12 months. The incidence of MACE was 13.8% (4/29). During the follow-up period, 2 patients died. One patient was hospitalized with recurrent myocardial infarction and one patient with heart failure. Survival analysis was performed 12 months after intervention and the cumulative survival rate was 80.0%. Conclusion: The application of VA-ECMO in CHIP interventional therapy is safe, effective and feasible.