Phosphatidylinositol 4-Kinase III Alpha Governs Cytoskeletal Organization for Invasiveness of Liver Cancer Cells.

BACKGROUND & AIMS: High expression of phosphatidylinositol 4-kinase III alpha (PI4KIIIα) correlates with poor survival rates in patients with hepatocellular carcinoma. In addition, hepatitis C virus (HCV) infections activate PI4KIIIα and contribute to hepatocellular carcinoma progression. We aimed at mechanistically understanding the impact of PI4KIIIα on the progression of liver cancer and the potential contribution of HCV in this process. METHODS: Several hepatic cell culture and mouse models were used to study the functional importance of PI4KIIIα on liver pathogenesis. Antibody arrays, gene silencing, and PI4KIIIα-specific inhibitor were applied to identify the involved signaling pathways. The contribution of HCV was examined by using HCV infection or overexpression of its nonstructural protein. RESULTS: High PI4KIIIα expression and/or activity induced cytoskeletal rearrangements via increased phosphorylation of paxillin and cofilin. This led to morphologic alterations and higher migratory and invasive properties of liver cancer cells. We further identified the liver-specific lipid kinase phosphatidylinositol 3-kinase C2 domain-containing subunit gamma (PIK3C2γ) working downstream of PI4KIIIα in regulation of the cytoskeleton. PIK3C2γ generates plasma membrane phosphatidylinositol 3,4-bisphosphate-enriched, invadopodia-like structures that regulate cytoskeletal reorganization by promoting Akt2 phosphorylation. CONCLUSIONS: PI4KIIIα regulates cytoskeleton organization via PIK3C2γ/Akt2/paxillin-cofilin to favor migration and invasion of liver cancer cells. These findings provide mechanistic insight into the contribution of PI4KIIIα and HCV to the progression of liver cancer and identify promising targets for therapeutic intervention.

Inhibition of TAF1B impairs ribosome biosynthesis and suppresses cell proliferation in stomach adenocarcinoma through promoting c-MYC mRNA degradation.

Hyperactivation of ribosome biosynthesis (RiBi) is a hallmark of cancer, and targeting ribosome biogenesis has emerged as a potential therapeutic strategy. The depletion of TAF1B, a major component of selectivity factor 1 (SL1), disrupts the pre-initiation complex, preventing RNA polymerase I from binding ribosomal DNA and inhibiting the hyperactivation of RiBi. Here, we investigate the role of TAF1B, in regulating RiBi and proliferation in stomach adenocarcinoma (STAD). We disclosed that the overexpression of TAF1B correlates with poor prognosis in STAD, and found that knocking down TAF1B effectively inhibits STAD cell proliferation and survival in vitro and in vivo. TAF1B knockdown may also induce nucleolar stress, and promote c-MYC degradation in STAD cells. Furthermore, we demonstrate that TAF1B depletion impairs rRNA gene transcription and processing, leading to reduced ribosome biogenesis. Collectively, our findings suggest that TAF1B may serve as a potential therapeutic target for STAD and highlight the importance of RiBi in cancer progression.

LncRNA HIF1A-AS2 mediates imatinib resistance by regulating autophagy in gastrointestinal stromal tumor cells.

The aim of this study was to explore the role and mechanism of long non-coding RNA (lncRNA) HIF1A antisense RNA 2 (HIF1A-AS2) in regulating imatinib (IM) resistance in gastrointestinal stromal tumor (GIST) cells under hypoxia. The expression of HIF1A-AS2 was silenced by siRNA in GIST cells. Cytotoxicity, apoptosis, and autophagy were evaluated under normoxic and hypoxic conditions. The expression levels of HIF1A-AS2, HIF1A, apoptosis-associated genes, and autophagy-associated genes were determined by qRT-PCR analysis and western blot. We found that lncRNA HIF1A-AS2 was highly expressed in GIST tissues and cells. Knockdown of HIF1A-AS2 increased the sensitivity of GIST cells to IM and increased apoptosis. Moreover, a hypoxic environment decreased the sensitivity of GIST cells to IM, and the knockdown of HIF1A-AS2 reversed this effect. Mechanistically, the knockdown of HIF1A-AS2 inhibited IM-mediated autophagy. Finally, HIF1A was found to positively regulate HIF1A-AS2 under hypoxic conditions. Collectively, these data demonstrate that hypoxia-induced HIF1A-AS2 promotes IM resistance in GIST cells by regulating autophagy.

Analysis of potential Circular RNAs in regulating imatinib resistance of Gastrointestinal stromal tumor.

INTRODUCTION: Recent studies have found that circular RNA is an abundant RNA species that belongs to part of the competing endogenous RNA network(ceRNA), which was proven to play an important role in the development, diagnosis and progress of diseases. However, the function of circRNAs in imatinib resistance in Gastrointestinal stromal tumor (GIST) are poorly understood so for. The present study aimed to screen and predict the potential circRNAs in imatinib resistance of GIST using microarray analysis. METHODS: We determined the expression of circular RNAs in paired normal gastric tissues(N), primary GIST (gastrointestinal stromal tumor) tissues (YC) and imatinib mesylate secondary resistance GIST tissues(C) with microarray and predicted 8677 dysregulated circular RNAs. RESULTS: Compared with the YC group, we identified 15 circRNAs that were up-regulated and 8 circRNAs that were down-regulated in the C group. Gene ontology (GO)and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that these host linear transcripts that differentially express circular RNAs are involved in many key biological pathways, predicting the potential tumor-genesis and drug resistance mechanismrelated to HIF-1 pathway, later we draw the cirRNA-miRNA-mRNA network involved in the HIF-1 pathway and found several dysregulated circRNAs and the relationship between circRNA-miRNAs-mRNA, such as circRNA_06551, circRNA_14668, circRNA_04497, circRNA_08683, circRNA_09923(Green, down-regulation) and circRNA_23636, circRNA_15734(Red, up-regulation). CONCLUSION: Taken together, we identified a panel of dysregulated circRNAs that may be potential biomarkers even therapy relevant to the GIST, especially imatinib secondary resistance GIST.

Evaluation the benefits of additional radiotherapy for gastric cancer patients after D2 resection using CT based radiomics.

OBJECTIVES: The value of adding radiotherapy (RT) is still unclear for patients with gastric cancer (GC) after D2 lymphadenectomy. The purpose of this study is to predict and compare the overall survival (OS) and disease-free survival (DFS) of GC patients treated by chemotherapy and chemoradiation based on contrast-enhanced CT (CECT) radiomics. METHODS: A total of 154 patients treated by chemotherapy and chemoradiation in authors' hospital were retrospectively reviewed and randomly divided into the training and testing cohorts (7:3). Radiomics features were extracted from contoured tumor volumes in CECT using the pyradiomics software. Radiomics score and nomogram with integrated clinical factors were developed to predict the OS and DFS and evaluated with Harrell's Consistency Index (C-index). RESULTS: Radiomics score achieved a C index of 0.721(95%CI: 0.681-0.761) and 0.774 (95%CI: 0.738-0.810) in the prediction of DFS and OS for GC patients treated by chemotherapy and chemoradiation, respectively. The benefits of additional RT only demonstrated in subgroup of GC patients with Lauren intestinal type and perineural invasion (PNI). Integrating clinical factors further improved the prediction ability of radiomics models with a C-index of 0.773 (95%CI: 0.736-0.810) and 0.802 (95%CI: 0.765-0.839) for DFS and OS, respectively. CONCLUSIONS: CECT based radiomics is feasible to predict the OS and DFS for GC patients underwent chemotherapy and chemoradiation after D2 resection. The benefits of additional RT only observed in GC patients with intestinal cancer and PNI.

Loss of lncRNA UCA1 ameliorates the injury managed by cerebral ischemia-reperfusion by sponging miR-18a-5p.

INTRODUCTION: Acute ischemic stroke (AIS) is a disease with high morbidity and mortality in the clinic. The current experiments aimed to study the effects of UCA1 interfering miR-18a-5p on cerebral ischemia-reperfusion (CI/R). MATERIAL AND METHODS: For rat models undergoing middle cerebral artery infarction (MCAO) surgery, the expression of UCA1 and miR-18a-5p was evaluated by qRT-PCR, and underlying function was identified by detecting infarct size, neurological scores, and inflammation. Luciferase report was applied to verify the relationship between UCA1 and miR-18a-5p. In the cell models, the impacts of UCA1 and miR-18a-5p were validated by CCK-8 assay, flow cytometry analysis, and ELISA. In patients with AIS, Pearson correlation was carried out to unveil the association between UCA1 and miR-18a-5p. RESULTS: The expression of UCA1 was at high levels and miR-18a-5p was at low levels in AIS patients. UCA1 knockdown showed a protective role in infarct size, neurofunction, and inflammation via binding miR-18a-5p. MiR-18a-5p participated in the regulation of UCA1 on cell viability, cell apoptosis, lactate dehydrogenase (LDH) levels, and inflammation. In patients with AIS, overexpression of UCA1 and underexpression of miR-18a-5p had a reverse correlation. CONCLUSIONS: Elimination of UCA1 was favourable to the recovery of the rat model and cells from CI/R damage by efficaciously sponging miR-18a-5p.

EPB41L4A-AS1 and UNC5B-AS1 have diagnostic and prognostic significance in osteosarcoma.

BACKGROUND: Deregulation of lncRNAs has been observed in human osteosarcoma. This study explored the diagnostic and prognostic significance of EPB41L4A-AS1 and UNC5B-AS1 in osteosarcoma. METHODS: Relative levels of EPB41L4A-AS1 and UNC5B-AS1 were detected in osteosarcoma tissue samples and cells. The ability to distinguish osteosarcoma from health was assessed by receiver operating characteristic (ROC) curve construction. Kaplan-Meier (K-M) and Cox proportional-hazards analyses were performed for prognosis factors. The bioinformatics approach was used to identify targeting miRNA for EPB41L4A-AS1 and UNC5B-AS1. Kaplan-Meier survival curves and Whitney Mann U tests were conducted for validating the statistical significance. In cell culture experiments, the influence of EPB41L4A-AS1 and UNC5B-AS1 on proliferation, migration, and invasion of the osteosarcoma cell line was examined by CCK-8 and Transwell assays. RESULTS: Levels of EPB41L4A-AS1 and UNC5B-AS1 were upregulated in osteosarcoma patients and cells compared with the healthy participants and normal cell lines. EPB41L4A-AS1 and UNC5B-AS1 have a potent ability to distinguish the patients with osteosarcoma from the health. EPB41L4A-AS1 and UNC5B-AS1 levels correlated with SSS stage. Patients with high levels of EPB41L4A-AS1 and UNC5B-AS1 had significantly shorter survival times. EPB41L4A-AS1 and UNC5B-AS1 were independent prognostic indexes for overall survival. miR-1306-5p was a common target for EPB41L4A-AS1 and UNC5B-AS1. A propulsive impact on cell proliferation, migration, and invasion by EPB41L4A-AS1 and UNC5B-AS1 was observed, but can be rescued by miR-1306-5p. CONCLUSIONS: It was concluded that upregulations of EPB41L4A-AS1 and UNC5B-AS1 expression were diagnostic and prognostic biomarkers for human osteosarcoma. EPB41L4A-AS1 and UNC5B-AS1 contribute to the biological behavior of osteosarcoma via miR-1306-5p.

A universal SARS-CoV DNA vaccine inducing highly cross-reactive neutralizing antibodies and T cells.

New variants in the SARS-CoV-2 pandemic are more contagious (Alpha/Delta), evade neutralizing antibodies (Beta), or both (Omicron). This poses a challenge in vaccine development according to WHO. We designed a more universal SARS-CoV-2 DNA vaccine containing receptor-binding domain loops from the huCoV-19/WH01, the Alpha, and the Beta variants, combined with the membrane and nucleoproteins. The vaccine induced spike antibodies crossreactive between huCoV-19/WH01, Beta, and Delta spike proteins that neutralized huCoV-19/WH01, Beta, Delta, and Omicron virus in vitro. The vaccine primed nucleoprotein-specific T cells, unlike spike-specific T cells, recognized Bat-CoV sequences. The vaccine protected mice carrying the human ACE2 receptor against lethal infection with the SARS-CoV-2 Beta variant. Interestingly, priming of cross-reactive nucleoprotein-specific T cells alone was 60% protective, verifying observations from humans that T cells protect against lethal disease. This SARS-CoV vaccine induces a uniquely broad and functional immunity that adds to currently used vaccines.

Global leadership initiative in malnutrition (GLIM) criteria using hand-grip strength adequately predicts postoperative complications and long-term survival in patients underwent radical gastrectomy for gastric cancer.

BACKGROUND: The present study aims to investigate whether malnutrition defined by the Global Leadership Initiative in Malnutrition (GLIM) criteria using hand-grip strength (HGS) adequately predict postoperative complications and long-term survival in patients underwent radical gastrectomy for gastric cancer in a similar manner to GLIM-defined malnutrition using skeletal muscle index (SMI). METHODS: Patients who underwent radical gastrectomy for gastric cancer from August 2014 to June 2019 were included in this study. Clinical data were prospectively collected. Malnutrition was diagnosed based on the two-step approach following the GLIM criteria. Skeletal muscle mass was assessed using SMI based on abdominal computed tomography (CT) scans, or assessed using HGS. RESULTS: A total of 1359 patients were included in this study, in which 36.2% of the patients were at risk of malnutrition (Nutritional Risk Screening 2002 scores ≥3). The incidence of malnutrition was 28.2% and 27.5% using SMI and HGS, respectively. There was a high agreement between the two criteria of malnutrition (kappa = 0.863, P < 0.001). Both of the two criteria of malnutrition were independently associated with postoperative complications (SMI-GLIM, P = 0.041; HGS-GLIM, P = 0.023), overall survival (P < 0.001, both), and disease-free survival (P < 0.001, both), with similar odds ratio or hazard ratio after adjusting for the same confounding variables. HGS-GLIM malnutrition (P = 0.046) but not SMI-GLIM malnutrition (P = 0.270) was associated with a higher incidence of severe complications. CONCLUSIONS: GLIM criteria using HGS is a useful tool to diagnose malnutrition and has a similar or even better predictive value for postoperative complications and long-term survival after radical gastrectomy for gastric cancer compared with GLIM criteria using SMI.

The relationship between the GLIM-defined malnutrition, body composition and functional parameters, and clinical outcomes in elderly patients undergoing radical gastrectomy for gastric cancer.

OBJECTIVE: The present study aims to determine the correlations between Global Leadership Initiative in Malnutrition (GLIM)-defined malnutrition and body composition and functional parameters, and to comprehensively analyze the predictive value of GLIM-defined malnutrition for postoperative outcomes in the context of detailed measurement of body composition and functional parameters in elderly patients who underwent radical gastrectomy for gastric cancer. METHODS: Elderly patients (aged ≥65 years) who underwent radical gastrectomy for gastric cancer from August 2014 to June 2019 were included. Malnutrition was diagnosed using the GLIM criteria. Skeletal muscle index (SMI), skeletal muscle density (SMD), subcutaneous fat area (SFA), and visceral fat area (VFA) were analyzed using abdominal computed tomography (CT) images. Handgrip strength and 6-m gait speed were measured. RESULTS: A total of 597 elderly patients were included in this study, in which 45.7% were at risk of malnutrition identified using Nutritional Risk Screening 2002 (NRS 2002), and 34.5% were diagnosed with malnutrition. Patients with malnutrition had lower SMI, SMD, SFA, VFA, lower handgrip strength and gait speed. Low handgrip strength and age ≥80 years were independent risk factors for postoperative complications, rather than GLIM-defined malnutrition. GLIM-defined malnutrition was independently associated with overall survival and disease-free survival after adjusting to the body composition and functional parameters in the multivariate analyses. CONCLUSIONS: GLIM-defined malnutrition was a better predictive factor than single parameters of body composition or physical function for survival in elderly gastric cancer patients. Handgrip strength can be used as a supportive measure to further improve the definition of malnutrition.

Value of muscle quality, strength and gait speed in supporting the predictive power of GLIM-defined malnutrition for postoperative outcomes in overweight patients with gastric cancer.

BACKGROUND: The present study aims to investigate the prognostic value of Global Leadership Initiative in Malnutrition (GLIM)-defined malnutrition in overweight patients who underwent gastrectomy for gastric cancer, and to explore whether the addition of muscle quality, strength and gait speed could improve the predictive power for postoperative outcomes. METHODS: Overweight patients (body mass index (BMI) ≥23 kg/m2) who underwent radical gastrectomy for gastric cancer were included in this study. Malnutrition was diagnosed using the two-step approach following the GLIM criteria. Skeletal muscle mass and quality was assessed using computed tomography (CT) determined skeletal muscle index (SMI) and skeletal muscle density (SMD), respectively. Hand-grip strength and 6-m gait speed were measured before surgery. RESULTS: A total of 587 overweight patients were included, in which 262 patients were identified as having obesity (BMI ≥25 kg/m2). The prevalence of malnutrition was 11.9% and 10.7% for overweight and obese patients, respectively. GLIM-defined malnutrition alone was not predictive for postoperative complications in overweight patients. The addition of low gait speed or muscle quality to GLIM-defined malnutrition led to a significant predictive value for postoperative complications. Low gait speed plus GLIM-defined malnutrition remained significant in the multivariate analysis. GLIM-defined malnutrition was predictive for overall survival (OS) and disease-free survival (DFS). Addition of low gait speed to GLIM-defined malnutrition increased the hazard ratio (HR) for the prediction of OS and DFS (univariate analysis: 2.880 vs. 2.238 for OS, 2.410 vs. 1.937 for DFS; multivariate analysis: 2.836 vs. 1.841 for OS, 2.433 vs. 1.634 for DFS). Addition of low hand-grip strength to GLIM-defined malnutrition led to a higher HR for the prediction of OS (2.144 vs. 1.841) in the multivariate analysis. CONCLUSION: Muscle quality, strength and gait speed added prognostic value to GLIM-defined malnutrition for the prediction of postoperative complications and/or survival in overweight patients who underwent radical gastrectomy for gastric cancer, especially gait speed, which could be incorporated into nutritional assessment protocols.

Measurement of muscle quantity/quality has additional predictive value for postoperative complications and long-term survival after gastrectomy for gastric cancer in patients with probable sarcopenia as defined by the new EWGSOP2 consensus: Analysis from a large-scale prospective study.

OBJECTIVES: We investigated whether measurement of muscle quantity/quality has additional predictive value for postoperative complications and long-term survival after gastrectomy for gastric cancer in patients with probable sarcopenia, as defined by the new European Working Group on Sarcopenia in Older People 2 consensus. METHODS: We conducted a prospective study of patients who underwent a radical gastrectomy for gastric cancer between August 2014 and June 2019. Muscle strength was measured using a handgrip dynamometer. Computed tomography images at the third lumbar vertebra level were used to assess muscle quantity and quality by the measuring cross-sectional muscle area and mean muscle attenuation, respectively. Probable sarcopenia was defined by low muscle strength. Sarcopenia was diagnosed by additional low muscle quantity or quality. Clinical outcomes were obtained by prospective data collection and follow up. RESULTS: Probable sarcopenia was identified in 419 patients, including 285 patients with sarcopenia. Patients with sarcopenia had a higher incidence of postoperative complications, higher costs, longer length of postoperative hospital stay, and worse overall survival (OS) and disease-free survival (DFS) compared with patients with low muscle strength only. The multivariate logistic analysis showed that sarcopenia and hypoproteinemia were independent risk factors for postoperative complications in patients with probable sarcopenia. Moreover, multivariate Cox analyses showed that sarcopenia remained an independent risk factor for OS and DFS in patients with probable sarcopenia. CONCLUSIONS: The measurement of muscle quantity/quality has additional predictive value for postoperative complications, OS, and DFS after gastrectomy for gastric cancer in patients with probable sarcopenia.

Impact of Body Composition and Physical Function on Quality of Life After Gastrectomy for Gastric Cancer.

PURPOSE: Patients with gastric cancer after gastrectomy often suffer from a decline in their quality of life (QoL), but the relationship between body composition (BC) and physical function on QoL has rarely been studied. This study aims to evaluate and determine the changes in QoL after gastrectomy and the impact of BC and physical function on QoL. METHODS: A total of 311 gastric cancer patients completed EORTC QLQ-C30 and EORTC QLQ-STO22 questionnaires before and 1, 3, 6 months post-surgery. Data including BC, handgrip strength (HGS) and 6-m gait speed (GS) were collected prospectively. Multiple linear regression analysis was used to determine the correlation between QoL and BC, HGS and GS. RESULTS: Patients had significantly worse scores after surgery on most function and symptom scales (p < 0.001), but most of these scales recovered within 6 months after surgery. A higher subcutaneous fat area (SFA)was associated with increased symptom scores 1 month after surgery. A higher GS is associated with a better global health status symptom. CONCLUSION: Patients suffer from a decline in their QoL after gastrectomy for gastric cancer. Intervention strategies aiming at reducing SFA and improving GS may improve the QoL in patients underwent gastrectomy for gastric cancer.

Laparoscopic versus open resection for elderly patients with gastric cancer: a double-center study with propensity score matching method.

PURPOSE: The applicability of laparoscopic-assisted radical gastrectomy for elderly patients with gastric cancer is still not well clarified. The aim of this double-center study was to explore the feasibility and effectiveness of laparoscopic-assisted radical gastrectomy on elderly patients with gastric cancer. METHODS: We prospectively collected data of patients who underwent gastrectomy for cancer in two centers from June 2016 to December 2019. Propensity score matching was performed at a ratio of 1:1 to compare the laparoscopic-assisted radical gastrectomy group and open radical gastrectomy group. Univariate analyses and multivariate logistic regression analyses evaluating the risk factors for total, surgical, and medical complications were performed. RESULTS: A total of 481 patients with gastric cancer met the inclusion criteria and were included in this study. After propensity score analysis, 258 patients were matched each other (laparoscopic-assisted radical gastrectomy (LAG) group, n = 129; open radical gastrectomy (OG) group, n = 129). LAG group had lower rate of surgical complications (P = 0.009), lower rate of severe complications (P = 0.046), shorter postoperative hospital stay (P = 0.001), and lower readmission rate (P = 0.039). Multivariate analyses revealed that anemia, Charlson comorbidity index, and combined resection were independent risk factors in the LAG group, whereas body mass index and American Society of Anesthesiology grade in the OG group. CONCLUSION: Laparoscopic-assisted radical gastrectomy was relative safe even effective in elderly gastric cancer patients. We should pay attention to the different risk factors when performing different surgical procedures for gastric cancer in elderly patients.

Value of Sarcopenia defined by the new EWGSOP2 consensus for the prediction of Postoperative Complications and Long-term Survival after Radical Gastrectomy for Gastric Cancer: A comparison with four common nutritional screening tools.

Background: Nutritional risk and sarcopenia are both associated with increased postoperative morbidity and mortality following elective surgery. This study aimed to investigate whether sarcopenia has additional predictive value for postoperative complications and long-term survival besides nutritional screening tools. Methods: Clinical data of patients underwent radical gastrectomy for gastric cancer was prospectively collected. Sarcopenia was diagnosed by grip strength plus muscle quanlity/quality based on preoperative abdominal CT scans. Nutritional screening was performed using 4 common nutritional screening tools, including Malnutrition Universal Screening Tool (MUST), Nutritional Risk Screening (NRS)-2002, Malnutrition Screening Tool (MST), and Short Nutritional Assessment Questionnaire (SNAQ). Results: A total of 880 patients were analyzed, in which 167 (18.98%) were diagnosed with sarcopenia. The incidence of nutritional risk identified by the 4 tools were 44.66% (MUST ≥1), 35.23% (NRS-2002 ≥3), 29.89% (MST ≥2), and 20.34% (SNAQ ≥2). Multivariate analyses showed that nutritional risk identified by the 4 nutritional screening tools were not independently associated with postoperative complications, overall survival (OS) or disease-free survival (DFS), except for NRS-2002 ≥3 as an independent risk factor of OS. Sarcopenia was always an independent risk factor for postoperative complications, OS, and DFS after adjusting for nutritional risk and the other covariates in the multivariate analyses. Conclusions: MUST, NRS-2002, MST, and SNAQ had low predictive power for postoperative complications and long-term survival in patients underwent radical gastrectomy for gastric cancer. Sarcopenia had additional predictive value for postoperative complications and long-term survival besides these nutritional screening tools and should be implemented in the preoperative assessments.

Downregulation of lncRNA CCDC26 contributes to imatinib resistance in human gastrointestinal stromal tumors through IGF-1R upregulation.

Imatinib is the first line of therapy for patients with metastatic or gastrointestinal stromal tumors (GIST). However, drug resistance limits the long-term effect of imatinib. Long non-coding RNAs (lncRNAs) are emerging as key players in regulating drug resistance in cancer. In this study, we investigated the association between lncRNA CCDC26 and IGF-1R in GIST and their involvement in drug resistance. Considering the key role of lncRNAs in drug resistance in cancer, we hypothesized that IGF-1R is regulated by lncRNAs. The expression of a series of reported drug resistance-related lncRNAs, including CCDC26, ARF, H19, NBR2, NEAT1, and HOTAIR, in GIST cells treated with imatinib H19 was examined at various time-points by qRT-PCR. Based on our results and published literature, CCDC26, a strongly down-regulated lncRNA following imatinib treatment, was chosen as our research target. GIST cells with high expression of CCDC26 were sensitive to imatinib treatment while knockdown of CCDC26 significantly increased the resistance to imatinib. Furthermore, we found that CCDC26 interacted with c-KIT by RNA pull down, and that CCDC26 knockdown up-regulated the expression of IGF-1R. Moreover, IGF-1R inhibition reversed CCDC26 knockdown-mediated imatinib resistance in GIST. These results indicated that treatments targeting CCDC26-IGF-1R axis would be useful in increasing sensitivity to imatinib in GIST.

Identification of imatinib-resistant long non-coding RNAs in gastrointestinal stromal tumors.

Long non-coding RNAs (lncRNAs) are an abundant RNA species that belong to the competing endogenous RNA network, which serves a critical role in the development, diagnosis and progression of diseases. Using chip technology, the current study analyzed the expression of lncRNAs in paired normal gastric tissues, primary gastrointestinal stromal tumor (GIST) tissues and GIST tissues resistant to imatinib mesylate. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to predict potential tumorigenesis and drug resistance mechanisms. The hypoxia-inducible factor-1 pathway was identified as a putative mediator of drug resistance. To the best of our knowledge, the current study was the first to investigate the role of lncRNAs in imatinib mesylate-resistant GISTs and primary GISTs using chip technology. An association was revealed between lncRNA expression and imatinib mesylate resistance. In summary, the current study identified a panel of dysregulated lncRNAs that may serve as potential biomarkers or drug targets for GISTs, particularly secondary imatinib-resistant GISTs.

Improved Stability, Antitumor Effect, and Controlled Release of Recombinant Soluble TRAIL by Combining Genetic Engineering with Coaxial Electrospinning.

Soluble tumor necrosis factor related apoptosis-inducing ligand (sTRAIL) is a promising candidate for antitumor protein drugs. However, the low stability and poor pharmacokinetic profile significantly limit its clinical application. In this work, a novel strategy was used to improve sTRAIL performance by combining genetic engineering with coaxial electrospinning. We first obtained a stable homotrimer via genetic engineering using the adenovirus knobless fiber motif to modify sTRAIL. In vitro studies showed that the engineered sTRAIL was more stable and had higher antitumor activity than wild sTRAIL. This new recombinant sTRAIL was then encapsulated into poly(lactic-co-glycolic acid) (PLGA) nanofibers by coaxial electrospinning to further enhance the stability and achieve the controlled release of sTRAIL. Surprisingly, the recombinant sTRAIL maintained its biological activity during the electrospinning process and exhibited a good cumulative release. The establishment of incorporation treatment of breast cancer mouse model demonstrated that the PLGA/sTRAIL nanofiber mats can effectively inhibit the growth of breast cancer tumor cells.

Downregulation of lncRNA CCDC26 contributes to imatinib resistance in human gastrointestinal stromal tumors through IGF-1R upregulation

Imatinib is the first line of therapy for patients with metastatic or gastrointestinal stromal tumors (GIST). However, drug resistance limits the long-term effect of imatinib. Long non-coding RNAs (lncRNAs) are emerging as key players in regulating drug resistance in cancer. In this study, we investigated the association between lncRNA CCDC26 and IGF-1R in GIST and their involvement in drug resistance. Considering the key role of lncRNAs in drug resistance in cancer, we hypothesized that IGF-1R is regulated by lncRNAs. The expression of a series of reported drug resistance-related lncRNAs, including CCDC26, ARF, H19, NBR2, NEAT1, and HOTAIR, in GIST cells treated with imatinib H19 was examined at various time-points by qRT-PCR. Based on our results and published literature, CCDC26, a strongly down-regulated lncRNA following imatinib treatment, was chosen as our research target. GIST cells with high expression of CCDC26 were sensitive to imatinib treatment while knockdown of CCDC26 significantly increased the resistance to imatinib. Furthermore, we found that CCDC26 interacted with c-KIT by RNA pull down, and that CCDC26 knockdown up-regulated the expression of IGF-1R. Moreover, IGF-1R inhibition reversed CCDC26 knockdown-mediated imatinib resistance in GIST. These results indicated that treatments targeting CCDC26-IGF-1R axis would be useful in increasing sensitivity to imatinib in GIST.

Chronic unpredictable stress abrogates the endotoxin tolerance induced by repeated peripheral LPS challenge via the TLR4 signaling pathway.

Endotoxin tolerance is induced by exposure to a repeated LPS challenge. Stress can exacerbate LPS-induced inflammation in the mouse hippocampus. However, the effects of stress on endotoxin tolerance have not been elucidated. The present experiments were designed to assess whether tolerance could be induced in the hippocampus by intraperitoneal injection of LPS at a dose of 250µg/kg for 7days, to investigate the effects of chronic unpredictable stress (CUS) on LPS-induced tolerance, and to assess underlying mechanisms in male Kunming mice. The levels of IL-1ß in the hippocampus increased to a plateau after 4days of LPS injection. When the CUS protocol was performed with concurrent LPS injections for 7days, body weight decreased, and IL-1ß expression in the hippocampus increased simultaneously. The expression of TLR4-MyD88-NF-κB signaling molecules and their negative regulators (PI3K, Akt) were also analyzed on day 7 after the last injection. The mRNA expression of TLR4 and MyD88 and the protein levels of TLR4 and NF-κBp65 were significantly increased, but the protein levels of PI3K and p-Akt were significantly decreased in the hippocampus of the mice. In conclusion, our findings show that endotoxin tolerance in the hippocampus was induced after four days of peripheral LPS challenge at a dose of 250µg/kg per day, and CUS abrogated this effect. CUS abolished endotoxin tolerance by reducing PI3K-mediated inhibition of TLR4-MyD88-NF-κB signaling pathways.