POU6F1 promotes ferroptosis by increasing lncRNA-CASC2 transcription to regulate SOCS2/SLC7A11 signaling in gastric cancer.

OBJECTIVE: This study investigated the effect and mechanism of POU6F1 and lncRNA-CASC2 on ferroptosis of gastric cancer (GC) cells. METHODS: GC cells treated with erastin and RSL3 were detected for ferroptosis, reactive oxygen species (ROS) level, and cell viability. The expression levels of POU6F1, lncRNA-CASC2, SOCS2, and ferroptosis-related molecules (GPX4 and SLC7A11) were also measured. The regulations among POU6F1, lncRNA-CASC2, FMR1, SOCS2, and SLC7A11 were determined. Subcutaneous tumor models were established, in which the expressions of Ki-67, SOCS2, and GPX4 were detected by immunohistochemistry. RESULTS: GC patients with decreased expressions of POU6F1 and lncRNA-CASC2 had lower survival rate. Overexpression of POU6F1 or lncRNA-CASC2 decreased cell proliferation and GSH levels in GC cells, in addition to increasing total iron, Fe2+, MDA, and ROS levels. POU6F1 directly binds to the lncRNA-CASC2 promoter to promote its transcription. LncRNA-CASC2 can target FMR1 and increase SOCS2 mRNA stability to promote SLC7A11 ubiquitination degradation and activate ferroptosis signaling. Knockdown of SOCS2 inhibited the ferroptosis sensitivity of GC cells and reversed the effects of POU6F1 and lncRNA-CASC2 overexpression on ferroptosis in GC cells. CONCLUSION: Transcription factor POU6F1 binds directly to the lncRNA-CASC2 promoter to promote its expression, while upregulated lncRNA-CASC2 increases SOCS2 stability and expression by targeting FMR1, thereby inhibiting SLC7A11 signaling to promote ferroptosis in GC cells and inhibit GC progression.

A Matching Strategy To Guide Donor Selection for Ulcerative Colitis in Fecal Microbiota Transplantation: Meta-Analysis and Analytic Hierarchy Process.

Fecal microbiota transplantation (FMT) targeting gut microbiota has recently been applied to the treatment of ulcerative colitis (UC). However, preliminary trials showed that only a subset of patients responded to FMT, and the heterogeneity in donor gut microbiota probably played important roles in patients' responses, implying the significance of matching an appropriate donor to a specified patient. We developed a strategy to build a donor-recipient matching model to guide rational donor selection for UC in FMT. We collected and uniformly reanalyzed 656 fecal 16S rRNA gene sequencing samples (350 from UC patients and 306 from healthy subjects) from 9 studies. Significantly lower α-diversity indexes were observed in UC patients by random effects model. Thirty-four bacterial genera and 34 predicted pathways were identified with significant odds ratios and classification potentials for UC patients. Based on six bacterial indicators, including richness, overall distance, genera, and pathways (beneficial and harmful), the analytic hierarchy process-based donor-recipient matching model was set to rank and select appropriate donors for patients with UC. Finally, the model showed favorable classification powers (>70%) for FMT effectiveness in two previous clinical trials. This study revealed the dysbiosis of fecal bacterial diversity, composition, and predicted pathways of patients with UC by meta-analysis and hereby developed a donor-recipient matching strategy to guide donor selection for UC in FMT. This strategy can also be applied to other diseases associated with gut microbiota. IMPORTANCE Modulation of gut microbiota by FMT from donors has been applied to the treatment of UC and yielded variable effectiveness in clinical trials. One possibility is that this variable effectiveness was related to donor selection, as a patient's response to FMT may rely on the capability of the used donor's microbiota to restore the specific gut disturbances of the patient. However, the biggest issues on the practical level are what should be considered in the selection process and how to set up such a donor-recipient matching model. In this study, we presented a bacterial profile-based donor-recipient matching strategy to guide donor selection for UC in FMT by first meta-analysis of 656 fecal 16S rRNA gene sequencing samples from 9 studies to identify significant indicators and then setting up the model by an analytic hierarchy process. The applicability and accuracy of this model were verified in the data sets from two previous FMT clinical studies. Our data indicate that the donor-recipient matching model built in this study enables researchers to rationally select donors for UC patients in FMT clinical practice, although it needs more samples and prospective trials for validation. The strategy adopted in this study to leverage existing data sets to build donor-recipient matching models for precision FMT is feasible for other diseases associated with gut microbiota.

Expression and significance of CDX2, FXR, and TGR5 in esophageal cancer.

This study explored the expression and significance of three critical morphogenesis genes in normal esophagus, reflux esophagitis (RE), Barrett's esophagus (BE), esophageal adenocarcinoma (EA), and esophageal squamous cell carcinoma (ESCC). Esophageal tissue samples and tissue microarrays were used. CDX2, FXR, and TGR5 protein expression were measured by immunohistochemistry in normal esophageal, RE, BE, EA, and ESCC tissues. All 3 proteins had markedly changed expression during the progression of EA. The expressions of CDX2 and FXR were positively correlated in EA. In addition, TGR5 expression was positively correlated with CDX2 in RE and BE. The expressions of CDX2 and FXR were also positively correlated in ESCC. Although CDX2, FXR, and TGR5 were upregulated in ESCC, these factors might not be markers for the prognosis of ESCC. These results suggested that CDX2, FXR, and TGR5 might play different roles in EA and ESCC. They may represent novel therapeutic targets for patients with these cancers.

Pneumocystis Jirovecii Pneumonia Diagnosis via Metagenomic Next-Generation Sequencing.

The incidence of non-HIV-infected Pneumocystis Jirovecii Pneumonia (PJP) is increasing. The prognosis for non-HIV PJP is poor and diagnostic tests are of lower sensitivity in non-HIV patients. Metagenomic next-generation sequencing (mNGS) was compared with routine detection assays, including Gomori methenamine silver (GMS) stain and polymerase chain reaction (PCR) technique. Specimens of 4 bronchoalveolar lavages (BAL) and 1 lung tissue samples were obtained from 4 non-HIV patients from our hospitals. Although both GMS and mNGS were positive for P. jirovecii with PCR as positive control, the testing time of mNGS was obviously shorter than GMS. Compared with the traditional GMS method, mNGS has absolute advantages. However, the issue with PJP presentations having atypical symptoms and ambiguous imaging features persists. Hence, the disease can easily be ignored. Secondly, PJP progresses rapidly in non-HIV-infected patients and can cause severe respiratory failure with unfavorable prognosis. This study affirms that mNGS can be used to quickly and accurately diagnose PJP, but a combination of clinical judgement of symptoms, laboratory testing, and imaging examination is required to make a comprehensive judgment along with mNGS test results.

Integrating Network Pharmacology, Transcriptome and Artificial Intelligence for Investigating Into the Effect and Mechanism of Ning Fei Ping Xue Decoction Against the Acute Respiratory Distress Syndrome.

Acute respiratory distress syndrome (ARDS) is a high-mortality disease and lacks effective pharmacotherapy. A traditional Chinese medicine (TCM) formula, Ning Fei Ping Xue (NFPX) decoction, was demonstrated to play a critical role in alleviating inflammatory responses of the lung. However, its therapeutic effectiveness in ARDS and active compounds, targets, and molecular mechanisms remain to be elucidated. The present study investigates the effects of NFPX decoction on ARDS mice induced by lipopolysaccharides (LPS). The results revealed that NFPX alleviated lung edema evaluated by lung ultrasound, decreased lung wet/Dry ratio, the total cell numbers of bronchoalveolar lavage fluid (BALF), and IL-1ß, IL-6, and TNF-α levels in BALF and serum, and ameliorated lung pathology in a dose-dependent manner. Subsequently, UPLC-HRMS was performed to establish the compounds of NFPX. A total of 150 compounds in NFPX were characterized. Moreover, integrating network pharmacology approach and transcriptional profiling of lung tissues were performed to predict the underlying mechanism. 37 active components and 77 targets were screened out, and a herbs-compounds-targets network was constructed. Differentially expressed genes (DEGs) were identified from LPS-treated mice compared with LPS combined with NFPX mice. GO, KEGG, and artificial intelligence analysis indicated that NFPX might act on various drug targets. At last, potential targets, HRAS, SMAD4, and AMPK, were validated by qRT-PCR in ARDS murine model. In conclusion, we prove the efficacy of NFPX decoction in the treatment of ARDS. Furthermore, integrating network pharmacology, transcriptome, and artificial intelligence analysis contributes to illustrating the molecular mechanism of NFPX decoction on ARDS.

Functional delivery of lncRNA TUG1 by endothelial progenitor cells derived extracellular vesicles confers anti-inflammatory macrophage polarization in sepsis via impairing miR-9-5p-targeted SIRT1 inhibition.

The delivery of biomolecules by extracellular vesicles (EVs) derived from endothelial progenitor cells (EPCs) has been proven to ameliorate sepsis, yet the therapeutic mechanism remains to be elucidated. Taurine upregulated gene 1 (TUG1) is a long noncoding RNA (lncRNA) that is downregulated in sepsis. The current study was designed to explore the role of EPCs derived EVs transmitting TUG1 in macrophage polarization and macrophage-mediated inflammation in a cecal ligation and puncture (CLP)-induced sepsis mouse model. TUG1 was underexpressed in CLP-induced sepsis, and its reexpression induced anti-inflammatory macrophage polarization and suppressed macrophage-medicated inflammatory injury to the pulmonary vascular endothelium. EPCs derived EVs transmitted TUG1 to promote M2 macrophage polarization. Luciferase, RIP, and RNA pull-down assays showed that TUG1 could competitively bind to microRNA-9-5p (miR-9-5p) to upregulate the expression of sirtuin 1 (SIRT1). Furthermore, EPCs derived EVs transmitted TUG1 to promote M2 macrophage polarization through the impairment of miR-9-5p-dependent SIRT1 inhibition. Finally, EPCs derived EVs carrying TUG1 were verified to ameliorate sepsis-induced organ damage in the murine model. In summary, EPCs derived EVs transmit TUG1 to attenuate sepsis via macrophage M2 polarization. This study also highlights the proinflammatory mechanism associated with miR-9-5p-mediated inhibition of SIRT1, which contributes to a more comprehensive understanding of the pathogenesis of sepsis.

A novel compound heterozygous mutation in ABCB4 gene in a pedigree with progressive familial intrahepatic cholestasis 3: a case report.

Progressive familial intrahepatic cholestasis (PFIC) includes a group of genetic autosomal recessive disorders that predominantly affects young children and results in early-onset progressive liver damage. Variations in ABCB4 have been shown to cause PFIC3. However, the association between ABCB4 genotype and clinical manifestations remains unclear. We investigated the clinical manifestations and genetic features of a Chinese Han pedigree with PFIC3. A 15-year-old boy, with high-serum gamma-glutamyl transferase (γ-GT) cholestatic cirrhosis, was diagnosed with PIFC3. After ursodeoxycholic acid (UDCA) treatment, the boy stayed in a relatively stable state with mild itching, and elevated γ-GT exhibited a remarkable decrease. Genetic testing identified a novel compound heterozygous mutation L842P/V1051A in ABCB4, which was inherited from his mother and father, respectively. Several predictive software suggested that these two mutations are pathogenic. Interestingly, the same compound heterozygous mutation was also found in his two sisters, one of whom had a history of intrahepatic cholestasis of pregnancy (ICP) and the other had asymptomatic gallstones. Therefore, this novel compound heterozygous mutation L842P/V1051A caused a continuum of ABCB4-related diseases including ICP, cholelithiasis and PFIC3 in our pedigree. The inconsistency between genotypes and phenotypes may be influenced by other factors. Genetic testing will be useful for diagnosis and genetic counseling.

MicroRNA-340-5p increases telomere length by targeting telomere protein POT1 to improve Alzheimer's disease in mice.

Alzheimer's disease (AD) is a chronic neurodegenerative disorder which is the primary cause of dementia in the elderly. Telomere attrition has been proposed as a hallmark of aging. Our study aimed to explore the mechanism of the protection of telomere 1 (POT1) in regulating telomere length and affecting cellular senescence in AD. The AD mouse model was established by d-galactose and aluminum chloride, and the water maze test and dark avoidance test were used to detect the behaviors of mice and confirm the success of AD mouse model. AD cell model was established with HT22 cells induced by Aß42 oligomers. POT1 expression in the AD model was detected by quantitative real-time polymerase chain reaction. Cellular telomere length in hippocampal tissue was analyzed by telomere restriction fragment. Localization of intracellular POT1, telomerase, and telomeres was analyzed by immunofluorescence and fluorescence in situ hybridization. Dual-luciferase assay was used to validate the targeted binding relationship between microRNA-340-5p (miR-340-5p) and POT1. After inhibiting POT1 expression, the symptoms of AD in mice were improved. Aß1-42 deposition was reduced, whereas telomere length and telomerase activity was increased. Dual-luciferase assay verified the binding relationship between miR-340-5p and POT1. An increase in miR-340-5p expression could alleviate cellular senescence and AD symptoms. miR-340-5p increased cellular telomere length and delayed cell senescence by inhibiting POT1 expression to improve AD symptoms. This study made a conclusion that miR-340-5p increased cellular telomere length and delayed cell senescence by inhibiting POT1 expression to improve AD symptoms in mice.

CircRNA GFRA1 promotes hepatocellular carcinoma progression by modulating the miR-498/NAP1L3 axis.

Circular RNAs (circRNAs) play essential roles in tumorigenesis and tumor progression. CircRNA GFRA1 (circGFRA1) was dysregulated in many cancer samples and acted as an independent marker for prediction of survivals in various cancer patients. However, the functions and molecular mechanisms of circGFRA1 in hepatocellular carcinoma (HCC) remain unclear. We collected 62 HCC tissues and normal adjacent tissues to evaluate the expression of circGFRA1 and the relationship between circGFRA1 expression and HCC patients' survival. We carried out a list of characterization experiments to investigate the roles and underling mechanisms of circGFRA1 and miR-498 in HCC progressions. CircGFRA1 was greatly increased in HCC tissues and cells, and the over-expression of circGFRA1 was intimately related with the advanced clinical stage and poor survival of HCC patients. The expression of circGFRA1 was negatively correlated with the expression of miR-498, but a positive correlation was found between circGFRA1 and NAP1L3 expression in HCC tissues. Silencing circGFRA1 inhibited the growth and invasion of hepatocellular carcinoma. Moreover, miR-498 over-expression or NAP1L3 inhibition could abrogate the oncogene role of circGFRA1 in HCC in vivo. Our findings indicated that circGFRA1 contributed to HCC progression by modulating the miR-498/NAP1L3 axis in HCC.

Discovery of oxyepiberberine as a novel tubulin polymerization inhibitor and an anti-colon cancer agent against LS-1034 cells.

Coptis chinensis Franch. has been extensively used in traditional Chinese medicine. The chemical structure of oxyepiberberine, as an alkaloid isolated from Coptis chinensis Franch., has been previously studied. However, anti-cancer effects and underlying mechanisms of oxyepiberberine need to be explored. This study aimed to investigate the anti-cancer effects and underlying mechanisms of oxyepiberberine on LS-1034 human colon cancer cells. The anti-proliferative effects of six derivatives of oxyepiberberine on colon cancer cells were assessed. Among six derivatives, oxyepiberberine showed the greatest anti-proliferative effect on LS-1034 cells with an IC50 value of 1.36 µM. Oxyepiberberine also induced apoptosis and inhibited migration of LS-1034 cells in a concentration-dependent manner. Importantly, oxyepiberberine was identified as a potent tubulin polymerization inhibitor. The tubulin polymerization inhibitory effects of oxyepiberberine in a concentration-dependent manner with an IC50 value of 1.26 µM were observed. A xenograft mouse model of colon cancer showed that oxyepiberberine could suppress tumor growth without an obvious toxicity. Conclusion Oxyepiberberine was found as a novel tubulin polymerization inhibitor, and it could be a promising agent to treat colon cancer.

Resveratrol inhibits bile acid-induced gastric intestinal metaplasia via the PI3K/AKT/p-FoxO4 signalling pathway.

Gastric intestinal metaplasia (GIM) is the essential pre-malignancy of gastric cancer. Chronic inflammation and bile acid reflux are major contributing factors. As an intestinal development transcription factor, caudal-related homeobox 2 (CDX2) is key in GIM. Resveratrol has potential chemopreventive and anti-tumour effects. The aim of the study is to probe the effect of resveratrol in bile acid-induced GIM. We demonstrated that resveratrol could reduce CDX2 expression in a time- and dose-dependent manner in gastric cell lines. A Cignal Finder 45-Pathway Reporter Array and TranSignal Protein/DNA Array Kit verified that resveratrol could increase Forkhead box O4 (FoxO4) activity and that Chenodeoxycholic acid (CDCA) could reduce FoxO4 activity. Furthermore, bioinformatics analysis showed that FoxO4 could bind to the CDX2 promoter, and these conjectures were supported by chromatin-immunoprecipitation (ChIP) assays. Resveratrol can activate FoxO4 and decrease CDX2 expression by increasing phospho-FoxO4 nucleus trans-location. Resveratrol could increase FoxO4 phosphorylation through the PI3K/AKT pathway. Ectopic FoxO4 expression can up-regulate FoxO4 phosphorylation and suppress CDCA-induced GIM marker expression. Finally, we found a reverse correlation between p-FoxO4 and CDX2 in tissue arrays. This study validates that resveratrol could reduce bile acid-induced GIM through the PI3K/AKT/p-FoxO4 signalling pathway and has a potential reversing effect on GIM, especially that caused by bile acid reflux.

Mesenchymal epithelial transition factor regulates tumor necrosis factor-related apoptotic induction ligand resistance in hepatocellular carcinoma cells through down-regulation of cyclin B1.

Tumor necrosis factor-related apoptotic induction ligand can induce cell apoptosis in various tumor cells. However, many cancer cells are resistant to tumor necrosis factor-related apoptotic induction ligand. Therefore, overcoming the tumor necrosis factor-related apoptotic induction ligand resistance makes it possible for tumor necrosis factor-related apoptotic induction ligand-based anti-cancer therapies. In this study, we took mesenchymal epithelial transition factor as the research target to study its role in tumor necrosis factor-related apoptotic induction ligand-resistant hepatocellular carcinoma. Mesenchymal epithelial transition factor gene has been proved to be an effective predictor of recurrence after hepatocellular carcinoma resection. The expression of mesenchymal epithelial transition factor and cyclin B1 were measured in tumor necrosis factor-related apoptotic induction ligand-resistant and non-resistant hepatocellular carcinoma tissues. Cyclin B1-knockdown and cyclin B1-overexpression hepatocellular carcinoma cells were treated with tumor necrosis factor-related apoptotic induction ligand; mesenchymal epithelial transition factor knockout, mesenchymal epithelial transition factor re-introduction and cyclin B1 restored in hepatocellular carcinoma cells treated with tumor necrosis factor-related apoptotic induction ligand were established. And MTT, bromodeoxyuridine, flow cytometry and western blotting were performed to evaluate the effect of mesenchymal epithelial transition factor and cyclin B1 on hepatocellular carcinoma cells treated with tumor necrosis factor-related apoptotic induction ligand. In addition, subcutaneous tumor transplantation in nude mice was conducted to access the effect of mesenchymal epithelial transition factor and cyclin B1 on tumor formation in vivo. In conclusion, cyclin B1 enhanced the cell growth and inhibited apoptosis in tumor necrosis factor-related apoptotic induction ligand-resistant hepatocellular carcinoma cells. And mesenchymal epithelial transition factor promoted the cell growth and apoptosis in tumor necrosis factor-related apoptotic induction ligand-resistant hepatocellular carcinoma cells by regulating cyclin B1. Therefore, mesenchymal epithelial transition factor regulates the cyclin B1 to regulate tumor necrosis factor-related apoptotic induction ligand resistance in hepatocellular carcinoma cells. Our results suggest a novel molecular mechanism for regulating tumor necrosis factor-related apoptotic induction ligand resistance, which might be helpful to select drug targets in the treatment of liver cancer.

Naked mole-rat very-high-molecular-mass hyaluronan exhibits superior cytoprotective properties.

Naked mole-rat (NMR), the longest-living rodent, produces very-high-molecular-mass hyaluronan (vHMM-HA), compared to other mammalian species. However, it is unclear if exceptional polymer length of vHMM-HA is important for longevity. Here, we show that vHMM-HA (>6.1 MDa) has superior cytoprotective properties compared to the shorter HMM-HA. It protects not only NMR cells, but also mouse and human cells from stress-induced cell-cycle arrest and cell death in a polymer length-dependent manner. The cytoprotective effect is dependent on the major HA-receptor, CD44. We find that vHMM-HA suppresses CD44 protein-protein interactions, whereas HMM-HA promotes them. As a result, vHMM-HA and HMM-HA induce opposing effects on the expression of CD44-dependent genes, which are associated with the p53 pathway. Concomitantly, vHMM-HA partially attenuates p53 and protects cells from stress in a p53-dependent manner. Our results implicate vHMM-HA in anti-aging mechanisms and suggest the potential applications of vHMM-HA for enhancing cellular stress resistance.

Inhibition of cyclinB1 Suppressed the Proliferation, Invasion, and Epithelial Mesenchymal Transition of Hepatocellular Carcinoma Cells and Enhanced the Sensitivity to TRAIL-Induced Apoptosis.

BACKGROUND: CyclinB1 is highly expressed in various tumor tissues and plays an important role in tumor progression. However, its role in hepatocellular carcinoma (HCC) remains unclear. Therefore, the aim of this study was to explore the role of cyclinB1 in the development and progression of HCC. METHODS: The expression of cyclinB1 was analyzed using the Gene Expression Profiling Interactive Analysis (GEPIA) database, and detected in HCC tissues and HCC cell lines through quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting. CyclinB1-short hairpin RNA (Sh-cyclinB1) was transfected into HCC cells to knockdown cyclinB1, and the effect of cyclinB1 knockdown on HCC was examined via the MTT assay, colony formation assay, wound healing assay, scratch assay, cell cycle analysis in vitro, and xenograft model in nude mice. In addition, the role of cyclinB1 on tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis was measured using flow cytometry and Western blotting. RESULTS: The GEPIA database analysis showed that cyclinB1 was highly expressed in HCC tissues. The results of qRT-PCR and Western blotting proved that the expression of cyclinB1 was significantly increased in HCC tissues and cell lines. The data of the MTT assay, colony formation assay, and cell cycle analysis indicated that cyclinB1 knockdown inhibited the proliferation of HCC cells. In addition, cell migration, invasion, and epithelial mesenchymal transition were also impaired by cyclinB1 knockdown. Furthermore, the xenograft model in nude mice demonstrated that inhibition of cyclinB1 suppressed tumor growth and metastasis in vivo. Finally, the results of flow cytometry and Western blotting indicated that inhibition of cyclinB1 enhanced the sensitivity of HCC cells to TRAIL-induced apoptosis. CONCLUSION: Overall, these data provide reasonable evidence that cyclinB1 may serve as a proto-oncogene during the progression of HCC.

DKK1 is epigenetically downregulated by promoter methylation and inhibits bile acid-induced gastric intestinal metaplasia.

Dickkopf-related protein 1 (DKK1) is essential to gastric cancer as an inhibitor of Wnt signaling. Gastric intestinal metaplasia (GIM) is an important precancerous lesion of gastric cancer that can be activated by bile acid reflux and chronic inflammation. However, the exact mechanism of DKK1 in bile acid-induced GIM has not been completely elucidated. We aimed to explore the epigenetic alterations and biological functions of DKK1 in the development of GIM. In the present study, bile acid was found to induce the expression of intestinal markers in gastric epithelial cells, whereas DKK1 was downregulated in response to bile acid stimulation. The mRNA and protein expression levels of DKK1 were decreased in GIM tissues as evidenced by qRT-PCR and immunohistochemical staining. Surprisingly, the methylation of the DKK1 promoter increased in GIM tissues, and we discovered 28 differential methylation sites of the DKK1 promoter in GIM tissues. Bile acid was able to induce the partial methylation of the DKK1 promoter, while 5-aza could increase DKK1 expression as well as decrease intestinal markers expression in gastric epithelial cells. In conclusion, the promoter methylation and downregulation of DKK1 might play important roles in the development of GIM, especially bile acid-induced GIM.

Down-regulation of CASC2 contributes to cisplatin resistance in gastric cancer by sponging miR-19a.

Increasing evidence suggests the involvement of long non-coding RNAs (lncRNAs) in chemoresistance of cancer treatment. However, their function and molecular mechanisms in gastric cancer chemoresistance are still not well elucidated. In the present study, we investigate the functional role of lncRNA cancer susceptibility candidate 2 (CASC2) in cisplatin (DDP) resistance of gastric cancer and discover the underlying molecular mechanism. Results revealed that CASC2 was decreased in DDP-resistant gastric cancer tissues and cells. Gastric cancer patients with low CASC2 expression levels had a poor prognosis. CASC2 overexpression enhanced DDP sensitivity of BGC823/DDP and SGC7901/DDP cells. Conversely, CASC2 knockdown weakened the response of BGC823 and SGC7901 to DPP. Moreover, CASC2 could function as a miR-19a sponge. miR-19a inhibition could overcome DDP resistance in BGC823/DDP and SGC7901/DDP cells, while miR-19a overexpression led to DDP resistance in BGC823 and SGC7901 cells. Notably, miR-19a overexpression counteracted CASC2 up-regulation-mediated enhancement in DDP sensitivity of BGC823/DDP and SGC7901/DDP cells. On the contrary, the inhibitory effect of CASC2 knockdown on the sensitivity of BGC823 and SGC7901 cells to DDP was reversed by miR-19a inhibition. In summary, CASC2 overexpression overcame DDP resistance in gastric cancer by sponging miR-19a, providing a novel therapeutic target for gastric cancer chemoresistance.

Intravenous administration of adipose tissue-derived stem cells enhances nerve healing and promotes BDNF expression via the TrkB signaling in a rat stroke model.

Previous studies have shown the beneficial effects of adipose-derived stem cells (ADSCs) transplantation in stroke. However, the molecular mechanism by which transplanted ADSCs promote nerve healing is not yet elucidated. In order to make clear the molecular mechanism for the neuroprotective effects of ADSCs and investigate roles of the BDNF-TrkB signaling in neuroprotection of ADSCs, we, therefore, examined the neurological function, brain water content, and the protein expression in middle cerebral artery occlusion (MCAO) rats with or without ADSCs transplantation. ADSCs were transplanted intravenously into rats at 30 minutes after MCAO. K252a, an inhibitor of TrkB, was administered into rats by intraventricular and brain stereotaxic injection. Modified neurological severity score tests were performed to measure behavioral outcomes. The results showed that ADSCs significantly alleviated neurological deficits and reduced brain water content in MCAO rats. The protein expression levels of BDNF and TrkB significantly increased in the cortex of MCAO rats with ADSCs treatment. However, K252a administration reversed the ADSCs-induced elevation of BDNF, TrkB, and Bcl-2 and reduction of Bax protein in MCAO rats. ADSCs promote BDNF expression via the TrkB signaling and improve functional neurological recovery in stroke rats.

[Isolation and characterization of dendritic cells from normal human esophageal mucosa].

AIM: To investigate the characteristics of dendritic cells (DCs) from normal human esophageal mucosa. METHODS: We collected normal esophageal mucosa samples from healthy individuals using endoscope and isolated mononuclear cells from the samples using Ficoll-Hypaque density gradient centrifugation. DCs were further separated by magnetic-activated cell sorting (MACS) to analyze DCs subsets by flow cytometry. RESULTS: Three mononuclear cell populations were detected in normal human esophageal mucosa: HLA-DR(high)/CD13(low);, HLA-DR(med)/CD13(+); and HLA-DR(-)/CD13(+). HLA-DR(high)/CD13(low); cells expressed the DCs-associated molecules and were referred to as esophageal mucosal DCs. The DCs were immature since they expressed low levels of CD80, CD83 and CD86. CONCLUSION: HLA-DR(high)/CD13(low); cells isolated from the normal human esophageal mucosa were proved to be DCs. DCs can be successfully isolated from esophageal mucosa.

[Relation between gastric dendritic cells and H pylori-associated gastritis].

AIM: To investigate the effects of gastric dendritic cells(DCs) in H.pylori-associated gastritis. METHODS: Mononuclear cells were isolated from gastric samples of endoscoped healthy subjects or patients with gastritis by Ficoll-hypaquetechnique. HLA-DR(+);DCs were further isolated by MACS. Rapid urease test, warthin-starry dyer and C(14);-urea breath test were used to detect H.pylori. The relationship between the quantity of gastric DCs and H.pylori density or inflammatory background were analysed. RESULTS: The gastric mononuclear cells from H.pylori-infected normal gastric mucosa contained more HLA-DR(+);DCs (17.93 % ) than that from noninfected subjects (4.93%).The quantity of gastric DCs is positively correlated with H.pylori density. The quantity of gastric DCs were significantly higher in moderate and high inflammatory gastric mucosa than that in low inflammatory gastric mucosa. There was no difference in the quantity of gastric DCs between moderate and high inflammatory gastric mucosa. CONCLUSION: Successfully isolated gastric DCs. DCs may play a role in the early stage of H.pylori-associated gastritis.

TRF2 promotes multidrug resistance in gastric cancer cells.

The role of telomere in drug resistance has not been clearly understood. Recent studies have been focused on telomerase activity and telomere length, but the findings are still controversial. It's been found that DNA double-strand breaks induced by anticancer drugs or irradiation increase TRF2 expression as an early response to DNA damage, which inhibits activation of ATM-dependent DNA damage response network, indicating TRF2 might probably be a general DNA-repair factor rather than merely a telomere-binding factor. In this study, the possible involvement of telomerase, telomere and TRF2 in DNA damage response and drug resistance was investigated. Telomere length was found elongated in multidrug-resistant variants of gastric cancer cell line SGC7901 treated with adriamycin or etoposide, however, drug-treatment per se had no effect on telomere length. Telomerase activity and TRF2 expression were upregulated after treatment, but not TRF1. TRF2 upregulation was more dramatic in drug-resistant cells and occurred before the expression of ATM, gammaH2AX and p53. Moreover, TRF2 inhibited the expression of ATM-dependent DSB responsive genes. Inhibition of TRF2 expression by RNA interference in drug-resistant cells partially reversed its resistance phenotype and overexpression of TRF2 in SGC7901 promoted its resistance phenotype. Taken together, current results indicate that TRF2 plays an important role in DNA damage response, and is involved in drug resistance of gastric cancer. Further study of the biological functions of TRF2 might be helpful to dissect the molecular mechanism of multiple drug-resistance and generate novel target to overcome it.