Structural insights into immune escape at killer T cell epitope by SARS-CoV-2 Spike Y453F variants.

CD8+ T cell immunity, mediated by human leukocyte antigen (HLA) and T cell receptor (TCR), plays a critical role in conferring immune memory and protection against viral pathogens. The emergence of SARS-CoV-2 variants poses a serious challenge to the efficacy of current vaccines. Whereas numerous SARS-CoV-2 mutations associated with immune escape from CD8+ T cells have been documented, the molecular effects of most mutations on epitope-specific TCR recognition remain largely unexplored. Here, we studied an HLA-A24-restricted NYN epitope (Spike448-456) that elicits broad CD8+ T cell responses in COVID-19 patients characterized by a common TCR repertoire. Four natural mutations, N450K, L452Q, L452R, and Y453F, arose within the NYN epitope and have transmitted in certain viral lineages. Our findings indicate that these mutations have minimal impact on the epitope's presentation by cell surface HLA, yet they diminish the affinities of their respective peptide-HLA complexes (pHLAs) for NYN peptide-specific TCRs, particularly L452R and Y453F. Furthermore, we determined the crystal structure of HLA-A24 loaded with the Y453F peptide (NYNYLFRLF), and subsequently a ternary structure of the public TCRNYN-I complexed to the original NYN-HLA-A24 (NYNYLYRLF). Our structural analysis unveiled that despite competent presentation by HLA, the mutant Y453F peptide failed to establish a stable TCR-pHLA ternary complex due to reduced peptide: TCR contacts. This study supports the idea that cellular immunity restriction is an important driving force behind viral evolution.

Mid-Long-Term Effect of Metabolic Surgery on Type 2 Diabetes in Nonobese Patients: a Meta-analysis.

BACKGROUND: This study aimed to perform a meta-analysis regarding the mid-long-term effect (≥ 2-year follow-up) of metabolic surgery on T2DM in non-obese patients. METHODS: PubMed, EMBASE and CENTRAL databases were searched for clinical studies from inception to March 2023. Stata 12.0 was used for data aggregation. Sensitivity, subgroup, and meta-regression analyses were performed when feasible. RESULTS: This meta-analysis included 18 articles involving 548 patients. A pooled rate of 47.5% of T2DM remission was found after metabolic surgery. To be more specific, 83.5% was obtained for hemoglobin A1c (HbA1c) < 7.0%, 45.1% for HbA1c < 6.5%, and 40.4% for HbA1c < 6.0%. Subgroup analysis showed that one-anastomosis gastric bypass (OAGB) had a higher remission rate (93.9%) than other surgeries. Studies conducted in America had a higher remission rate (61.4%) than in Asia (43.6%). Meta-regression analysis displayed that publication year, number of patients, study design, preoperative age, BMI, and quality assessment score were not significantly associated with T2DM remission rate. Additionally, metabolic surgery could result in significant reductions in BMI (-4.133 kg/m2), weight (-9.874 kg), HbA1c (-1.939%), fasting blood glucose, fasting C-peptide, and fasting insulin. However, metabolic surgery seemed to have poorer glycemic control in non-obese than obese T2DM patients. CONCLUSION: A moderate mid-long-term effect of T2DM remission was observed after metabolic surgery in non-obese patients. However, we still need more prospective multi-institutional studies using the same definitions for diabetes and the same surgical technique for the surgery. Without this, the exact role of bariatric surgery in non-obese patients is unanswered.

MicroRNA-5195-3p mediated malignant biological behaviour of insulin-resistant liver cancer cells via SOX9 and TPM4.

BACKGROUND: Primary liver cancer is a malignant tumour of the digestive system, ranking second in cancer mortality in China. In different types of cancer, such as liver cancer, microRNAs (miRNAs) have been shown to be dysregulated. However, little is known about the role of miR-5195-3p in insulin-resistant liver cancer. METHODS AND RESULTS: In this study, in vitro and in vivo experiments were conducted to identify the altered biological behaviour of insulin-resistant hepatoma cells (HepG2/IR), and we proved that HepG2/IR cells had stronger malignant biological behaviour. Functional experiments showed that enhanced expression of miR-5195-3p could inhibit the proliferation, migration, invasion, epithelial-mesenchymal transition (EMT) and chemoresistance of HepG2/IR cells, while impaired expression of miR-5195-3p in HepG2 cells resulted in the opposite effects. Bioinformatics prediction and dual luciferase reporter gene assays proved that SOX9 and TPM4 were the target genes of miR-5195-3p in hepatoma cells. CONCLUSIONS: In conclusion, our study demonstrated that miR-5195-3p plays a critical role in insulin-resistant hepatoma cells and might be a potential therapeutic target for liver cancer.

DNMT1 mediates proliferation, migration and invasion of extravillous trophoblasts by regulating the methylation level of APLNR.

INTRODUCTION: Proliferation, migration and invasion of extravillous trophoblasts (EVTs) play an important role in the progression of preeclampsia (PE). The purpose of this study was to investigate the molecular mechanism by which DNA methylase regulates the transcription level of APLNR and affects the phenotypic function of EVTs. MATERIALS AND METHODS: PE mice model and H/R model in HTR8/Svneo cells were constructed. Clinical samples of normal pregnant women and PE patients were collected. Expression and methylation level of APLNR in vivo and in vitro were detected. ChIP-qPCR was used to detect the binding of DNA methyltransferase at the APLNR promoter. The expression of DNA methyltransferase 1 (DNMT1), NO and eNOS in vitro were detected. EVTs proliferation, migration and invasion in vitro were detected. RESULTS: In placental tissues or HTR8/Svneo cells of the PE model group, the expression of APLNR was reduced and APLNR methylation level was up-regulated. There was no significant difference in the APLNR expression in placental tissues between normal pregnant women and PE patients. H/R conditions only promote the binding of DNMT1 at the APLNR promoter. DNMT1 interference decreased the enrichment degree of DNMT1 in APLNR promoter region and up-regulated the mRNA and protein levels of APLNR in vivo and in vitro. The activation of APLNR by Elabela (ELA) can promote eNOS transcription, thereby promoting cell proliferation and NO level, while eNOS inhibitor can reverse this effect. DNMT1 down-regulation inhibted APLNR methylation level, promoted eNOS transcription, and promoted EVTs proliferation, migration and invasion, which could be revised by the interference of APLNR. DISCUSSION: DNMT1 promotes eNOS transcription by inhibting APLNR methylation level, and promotes EVTs proliferation, migration and invasion, thus providing a new and broad application prospect for PE treatment.

Complete uni-port video-assisted thoracoscopic surgery for surgical stabilization of rib fractures: a case report.

BACKGROUND: Rib fractures are a common injury in trauma. Potential complications include pain, pneumonia, respiratory failure, disability, and death. Surgical stabilization of rib fractures (SSRF) has become an available treatment option, and complete video-assisted thoracoscopic surgery (VATS) for SSRF is gradually accepted because of minimally invasive and pain relief. To our knowledge, complete uni-port VATS for SSRF has not yet been reported. CASE PRESENTATION: A 53-year-old man accidentally fell off a three-meter high scaffolding while working resulting in severe chest pain and shortness of breath. He was found with left 7th through 11th rib fractures with a pulmonary contusion from computed tomography (CT). A 4 cm incision was made in the 7th intercostal space in the midaxillary line, and complete uni-port VATS for SSRF were operated. The patient's pain was significantly relieved after the operation, and the scar was tiny and unapparent. CONCLUSIONS: Complete uni-port VATS for SSRF is a novel and modificatory method of operation with the benefit of minimal invasion, meanwhile, intrathoracic injuries could be treated at the same time. Further study is warranted.

Is the urinary iodine/creatinine ratio applicable to assess short term individual iodine status in Chinese adults? Comparison of iodine estimates from 24-h urine and timed-spot urine samples in different periods of the day.

BACKGROUND: Urinary iodine concentration (UIC) is routinely used to evaluate the population iodine status while the uniform method for the individual level assessment is uncertain. OBJECTIVES: To explore the 24-h urinary iodine excretion (UIE) in five different periods of the day and the corresponding prediction equations respect by the use of creatinine-corrected UIC. METHODS: We collected 24-h, spot and fasting urine in five periods of the day to estimate 24-h UIE by the six different prediction equations. We compared the estimated creatinine-corrected UIC to the collected 24-h UIE and identified the most suitable equations in each period of the day. RESULTS: Among the six different prediction equations, the equation of Kawasaki T was the best to estimate the 24-h UIE by fasting urine among Chinese adults. Among the five periods of time, the equation of Knudsen N was the best to estimate the 24-h UIE in the non-morning period. CONCLUSION: Urinary iodine status at the individual level could be estimated by different creatinine-based equations at different periods of the day.

iTRAQ-Based Proteome Profiling of Differentially Expressed Proteins in Insulin-Resistant Human Hepatocellular Carcinoma.

Recently, the incidences of insulin resistance (IR) and IR-related complications have increased throughout the world, which also associate with poor prognosis in hepatocellular carcinoma (HCC). Numerous studies had been focused on the role of IR in tumorigenesis and prognosis of HCC. The proteomic analysis of IR related hepatocellular carcinoma had not been reported by now. In the present study, 196 differentially expressed proteins (DEPs) were identified between insulin resistant HepG2 cells and their parental cells, of which 109 proteins were downregulated and 87 proteins were upregulated. Bioinformatics analysis indicated that these DEPs were highly enriched in process of tumorigenesis and tumor progression. PPI network analysis showed that SOX9, YAP1 and GSK3ß as the key nodes, were involved in Wnt and Hippo signaling pathways. Survival analysis revealed that high expression of SOX9 and PRKD3 were strongly associated with reduced patient survival rate. parallel reaction monitoring (PRM) and Western blot analysis were applied to verify the protein level of these four key nodes mentioned above, which showed the same trend as quantified by isobaric tags for relative and absolute quantitation (iTRAQ) and confirmed the reliability of our Proteome Profiling analysis. Our results indicated that IR related dysregulation of protein expression might participated in tumorigenesis and malignant phenotype of hepatocarcinoma cells.

Value of biomarkers in epithelial-mesenchymal transition models of liver cancer under different interventions: a meta-analysis.

Aim: A meta-analysis was conducted to evaluate the effectiveness of crucial biomarkers in HepG2 cells during epithelial-mesenchymal transformation induced by multiple interventions. Methods: PubMed, Web of Science, Embase, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Wan Fang Data and VIP databases were systematically searched from inception to 14 June 2020, by two independent reviewers. Results: A total of 58 studies were included in the meta-analysis. E-cadherin, N-cadherin and vimentin performed well under medicinal interventions. E-cadherin worked well under genetic interventions. E-cadherin and N-cadherin also performed significantly well under tumor microenvironment interventions. Under ncRNA interventions, the expression of E-cadherin significantly changed. Conclusion: Different sets of biomarkers should be selected under various interventions based on their performance.

LIGHT (TNFSF14) inhibits glucose uptake of adipocytes by downregulating GLUT4 expression via AKT signaling pathway.

Glucose homeostasis of adipocytes could be regulated by immune-adipose crosstalk. In order to investigate the effects of Lymphotoxin-like inducible protein that competes with glycoprotein D for herpesvirus entry on T cells (LIGHT) on glucose metabolism, we performed the present study. Our results showed that LIGHT deficiency improved glucose tolerance and enhanced glucose consumption of inguinal white adipose tissue (iWAT) under high fat diet. Consistently, Light overexpression could inhibit glucose uptake during the process of white adipogenesis. Mechanistically, LIGHT interacted with lymphotoxin-ß receptor (LTßR) to attenuate AKT pathway leading to downregulation of glucose transporter-4 (GLUT4) expression, which resulted in glucose uptake inhibition. In summary, our findings revealed LIGHT-LTßR-AKT-GLUT4 axis as a regulator of glucose uptake in adipose tissue, which suggested the pivotal role of LIGHT in maintaining glucose homeostasis.

Dilemma and path selection of college sports resources into the public service system of national fitness in the new era / Dilema e seleção do caminho dos recursos desportivos universitários que integram o sistema nacional de serviços públicos de educação física na nova era / Dilemas y opciones para la integración de los recursos deportivos de la nueva era en el servicio público universal de gimnasia

ABSTRACT With the improvement of people's yearning for a healthy and beautiful life, national fitness has become a hot word in academic circles. Combining Data Envelopment Analysis (DEA) and the Tobit technology, this paper constructs the evaluation model of college sports resource efficiency based on the DEA Tobit model. Based on the establishment of the input-output index system of college sports resources, the model achieves the effect of accurate analysis on the allocation efficiency of university sports resources. Taking 10 universities in a city as experimental objects, the model is verified. The verification shows that the three efficiency indexes of STU University and IPE University in group M are all 1, which shows that the resource allocation is more reasonable; the comprehensive efficiency of Ju university is low, and the sports resources investment is excessive; in group n, except for the EU University, the efficiency of other colleges and universities is lower than the pass line. It can be concluded that there are problems such as excessive input of sports resources and low output rate in Colleges and universities of a city. Therefore, colleges and universities in a city should make full use of the existing resources, enhance their social sports guidance force, while improving the publicity of national fitness. This study has high reference significance for the path selection of national fitness integration in Colleges and Universities.

RESUMO Com a melhoria do desejo das pessoas por uma vida saudável e agradável, a atividade física nacional tornou-se a palavra de ordem nos círculos acadêmicos. Combinando a Análise por Envoltória de Dados (DEA, do inglês Data Envelopment Analysis) e a tecnologia Tobit, foi construído o modelo de avaliação da eficiência dos recursos desportivos universitários com base no modelo DEA Tobit. Com base no estabelecimento do sistema de índice de entradas-resultados dos recursos desportivos universitários, o modelo produz o efeito de uma análise precisa da eficiência de alocação dos recursos desportivos universitários. Tomando dez universidades de uma cidade como objetos experimentais, o modelo é verificado. Após verificação, os três índices de eficiência da Universidade de Stu e da Universidade de IPE no Grupo M são todos 1, o que indica que a alocação de recursos é mais razoável; a eficiência global da Universidade de Ju é inferior à da Universidade UE, e a eficiência de outras universidades do Grupo n é inferior à linha de aprovação, com excepção da Universidade UE. Os resultados mostram que há alguns problemas nos recursos esportivos de faculdades e universidades em uma cidade, como muita entrada de recursos esportivos e baixos resultados. Por conseguinte, as escolas e universidades urbanas devem utilizar plenamente os recursos existentes, reforçar a orientação dos esportes sociais e melhorar a divulgação da aptidão física nacional. Este estudo tem um alta relevância de referência para a seleção do caminho da integração da atividade física nacional em faculdades e universidades.

RESUMEN Con el aumento del deseo de las personas de tener una vida saludable y plena, la educación física nacional se ha convertido en un concepto imperativo en los círculos académicos. Combinando el Análisis Envolvente de Datos (DEA) y la tecnología Tobit, este documento construye el modelo de evaluación de la eficiencia de los recursos deportivos universitarios basándose en el modelo Tobit DEA. Con el uso del sistema de índice de insumo-resultado de los recursos deportivos universitarios, el modelo logra un análisis preciso de la eficiencia de asignación de dichos recursos. El modelo es verificado tomando 10 universidades de una ciudad como objetos experimentales. La verificación muestra que los tres índices de eficiencia de la Universidad STU y de la Universidad IPE en el grupo M son todos 1, lo que demuestra que la asignación de recursos es más eficaz. Por otra parte, la eficiencia integral de la universidad de Ju es baja y la inversión en recursos deportivos es excesiva. En el grupo n, a excepción de la Universidad EU, la eficiencia de otros colegios y universidades es menor que la línea de aprobación. Se puede concluir que existen problemas como la inversión excesiva en recursos deportivos y la baja tasa de resultados en los colegios y universidades de una ciudad. Por lo tanto, los colegios y universidades deben aprovechar al máximo los recursos existentes, reforzando la orientación respecto a los deportes sociales y, al mismo tiempo, mejorando la publicidad de la educación física nacional. Este estudio tiene una gran importancia como referencia para la selección del camino de integración nacional de la educación física en colegios y universidades.

[Protection effect of baicalin-regulated IKKα on inflammatory reaction of human oral keratinocytes].

PURPOSE: To observe the regulation of baicalin on IKKα mediated MASPIN in Human oral keratinocytes (HOKs) inflammatory reaction, this study was to explore the molecular regulation mechanism of baicalin on oral mucosal inflammation. METHODS: HOKs were stimulated by lipopolysaccharide (LPS) to mimic the inflammatory response of oral mucosal inflammation in vitro. CCK-8 assay was used to detect the toxicity of baicalin to HOKs; then different concentrations of baicalin were pre-treated to LPS-stimulated HOKs, enzyme-linked immunosorbent assays (ELISA) was used to detect the secretion of IL-6 and TNF-α in LPS-stimulated HOKs; reverse transcription polymerase chain reaction(RT-PCR) and Western blot assay were used to detect the regulatory effects of baicalin on gene and protein expression levels of IKKα mediated MASPIN in LPS-stimulated HOKs. SPSS 21.0 software package was used for statistical analysis of the data. RESULTS: HOKs stimulated by 10 µg/mL LPS successfully simulated the inflammatory environment of oral mucosal inflammation. The concentration of baicalin between 1 µg/mL and 20 µg/mL had no toxic effect on HOKs. With the increasing concentration of baicalin, the expression of MASPIN increased gradually, while the expression of IKKα and inflammatory factors decreased gradually(P＜0.05). CONCLUSIONS: Baicalin can decrease the expression of inflammatory factors in LPS-stimulated HOKs, down-regulate IKKα and up-regulate MASPIN.

iTRAQ-Based Phosphoproteomic Analysis of Toxoplasma gondii Tachyzoites Provides Insight Into the Role of Phosphorylation for its Invasion and Egress.

The invasion and egress are two key steps in lytic cycle vital to the propagation of Toxoplasma gondii infection, and phosphorylation is believed to play important roles in these processes. However, the phosphoproteome of T. gondii at these two stages has not been characterized. In this study, we profiled the phosphoproteome of tachyzoites at the stages of "just invading" (JI) and "prior to egress" (PE) based on iTRAQ quantitative analysis, in which a total of 46 phosphopeptides, 42 phosphorylation sites, and 38 phosphoproteins were detected. In the comparison of PE vs. JI, 10 phosphoproteins were detected with their phosphorylation level significantly changed, and four of them were demonstrated to be significantly down-regulated at the transcriptional level. Bioinformatic analysis of these identified phosphoproteins suggested that phosphorylation-mediated modulation of protein function was employed to regulate the pathway of toxoplasmosis and metabolism and cellular processes correlated with tachyzoite's binding, location, and metabolism, and thus play vital roles in the parasite lytic cycle. Moreover, cytoskeletal network (CN)-associated Inner Membrane Complex (IMC1, IMC4, IMC6 and IMC12), Intravascular Network (IVN)-related GRAs (GRA2, GRA3, GRA7 and GRA12), and Parasitophorous Vacuole Membrane (PVM)-localized ROP5 were shown to be enriched at the central nodes in the protein interaction network generated by bioinformatic analysis, in which the phosphorylation level of IMC4, GRA2, GRA3, and GRA12 were found to be significantly regulated. This study revealed the main cellular processes and key phosphoproteins crucial for the invasion and egress of T. gondii, which will provide new insights into the developmental biology of T. gondii in vitro and contribute to the understanding of pathogen-host interaction from the parasite perspective.

Evaluation of toxoplasmosis in pregnant women using dot-immunogold-silver staining with recombinant Toxoplasma gondii peroxiredoxin protein.

BACKGROUND: Toxoplasma gondii infection endangers human health and affects animal husbandry. Serological detection is the main method used for epidemiological investigations and diagnosis of toxoplasmosis. The key to effective diagnosis of toxoplasmosis is the use of a standardized antigen and a specific and sensitive detection method. Peroxiredoxin is an antigenic protein and vaccine candidate antigen of T. gondii that has not yet been exploited for diagnostic application. METHODS: In this study, recombinant T. gondii peroxiredoxin protein (rTgPrx) was prepared and used in dot-immunogold-silver staining (Dot-IGSS) to detect IgG antibodies in serum from mice and pregnant women. The rTgPrx-Dot-IGSS method was established and optimized using mouse serum. Furthermore, serum samples from pregnant women were analyzed by rTgPrx-Dot-IGSS. RESULTS: Forty serum samples from mice infected with T. gondii and twenty negative serum samples were analyzed. The sensitivity and specificity of rTgPrx-Dot-IGSS were 97.5 and 100%, respectively, equivalent to those of a commercial ELISA kit for anti-Toxoplasma IgG antibody. Furthermore, 540 serum samples from pregnant women were screened with a commercial ELISA kit. Eighty-three positive and 60 negative serum samples were analyzed by rTgPrx-Dot-IGSS. The positive rate was 95.18%, comparable to that obtained with the commercial ELISA kit. CONCLUSIONS: The Dot-IGSS method with rTgPrx as an antigen might be useful for diagnosing T. gondii infection in individuals.

Diagnosis and Treatment of Breast Cancer in the Precision Medicine Era.

Breast cancer is one of the most leading causes of death for women worldwide. According to statistics published by the International Agency for Research on Cancer (IARC), the incidence of breast cancer is on the rise year by year in most parts of the world. The existence of heterogeneity limits the early diagnosis and targeted therapy of breast cancer. Nowadays, precision medicine brings a new perspective to personalized diagnosis and targeted therapy, overcomes the heterogeneity of different patients, and provides an opportunity for screening of high-risk populations. As a clinician, we are committed to using genomic to provide a favorable perspective in the field of breast cancer. The current review describes the recent advances in the understanding of precision medicine for breast cancer in the aspect of the genomics which could be applied to improve our ability to diagnose and treat breast cancer individually and effectively.

Global Analysis of miRNA Signature Differentially Expressed in Insulin-resistant Human Hepatocellular Carcinoma Cell Line.

Chemoresistance mediated by insulin resistance (IR) in HCC has already been validated. However, the underlying mechanism, especially the involvement of microRNAs (miRNAs) was unelucidated. In this study, miRNA microarrays and bioinformatics methods were employed to determine the dysregulation of miRNA by IR in HCC cells, and quantitative RT-PCR (qRT-PCR) was applied to valid the miRNA array data. Of all the 2006 miRNAs screened, 32 miRNAs were found up or down regulated between the HepG2/IR cells and its parental cells. Further literature mining revealed that some of these miRNAs may function as oncogenes or tumor suppressors that contribute to tumor progression, recurrence, and metastasis which eventually lead to chemotherapeutic resistance. Interestingly, bioinformatics analysis by Gene Ontology (GO) enrichment pathway indicating that function of the predicted target genes of these dysregulated miRNAs were significantly enriched in the processes related with biosynthesis, catabolism, modification etc., and Kyoto Encyclopedia of Genes and Genomes (KEGG) mapping showed that the biological regulatory mechanisms were integrated in cancer-related pathways. Moreover, we also constructed a network which connected the differentially expressed miRNAs to target genes, GO enrichments and KEGG pathways to reveal the hub miRNAs, genes and pathways. Collectively, our present study demonstrated the possible miRNAs and predicted target genes involving in the pathophysiology of insulin resistant HCC, providing novel insights into the molecular mechanisms of multidrug resistance in the insulin resistant HepG2 cells.

Influences of operating parameters on liquefaction performances of Tetra Pak in sub-/supercritical water.

Liquefaction performances of waste Tetra Pak in sub-/supercritical water were evaluated in micro-batch reactors. The influences of temperature (300-420 °C), pressure (16-24 MPa), residence time (5-60 min) and feed concentration (5-40 wt%) on bio-oil yield, high heating value (HHV), and functional groups in bio-oil were investigated. The results showed that bio-oil yield firstly increased with increasing temperature and then decreased when the temperature exceeded 360 °C. Reaction time longer than 30 min gave a negative effect on bio-oil yield. The influence of pressure on bio-oil yield increased markedly from 16 MPa to 22 MPa, and then stabilized. The feed concentration higher than 20 wt% showed little influence on bio-oil yield. Maximum bio-oil yield of 35.55% was found at 360 °C, 22 MPa, 30 min and feed concentration of 20 wt%. HHV and energy recovery efficiency increased significantly with temperature, and maximum HHV of 48.747 MJ/kg and energy recovery efficiency of 46.49% were found at 420 °C, 20 MPa, 30 min and feed concentration of 20 wt%. The main compounds in bio-oil and morphology of the solid residue were also analyzed, and the possible liquefaction pathways of Tetra Pak were proposed.

Autophagy Plays a Critical Role in Insulin Resistance- Mediated Chemoresistance in Hepatocellular Carcinoma Cells by Regulating the ER Stress.

The high mortality of hepatocellular carcinoma (HCC) patients is associated with several independent risk factors including type 2 diabetes mellitus (T2DM) and insulin resistance (IR), which could be caused by various pathological processes such as tumorigenesis and inflammation in the liver. In previous report, we declared that IR contributes to multidrug resistance in HCC by activation of endoplasmic reticulum (ER) stress. Here, our study revealed that the enhanced autophagy induced by IR significantly prompts the chemotherapeutic drug resistance in hepatoma cells, which was validated by stimulation and inhibition of the autophagy respectively. A potential reason is that autophagy acts as a regulator of ER stress in the IR-mediated chemoresistance in HCC. In conclusion, autophagy facilitates the HCC survival in chemotherapeutic drug treatment by maintaining the homeostasis in the ER indicating the regulatory role of autophagy in ER stress contributes to IR-mediated chemoresistance in hepatocellular carcinoma cells. Collectively, these data implied inhibition of autophagy is a potential treatment of inherent IR-mediated chemoresistance in HCC.

Characteristics of doxorubicin-selected multidrug-resistant human leukemia HL-60 cells with tolerance to arsenic trioxide and contribution of leukemia stem cells.

The present study selected and characterized a multidrug-resistant HL-60 human acute promyelocytic leukemia cell line, HL-60/RS, by exposure to stepwise incremental doses of doxorubicin. The drug-resistant HL-60/RS cells exhibited 85.68-fold resistance to doxorubicin and were cross-resistant to other chemotherapeutics, including cisplatin, daunorubicin, cytarabine, vincristine and etoposide. The cells over-expressed the transporters P-glycoprotein, multidrug-resistance-related protein 1 and breast-cancer-resistance protein, encoded by the adenosine triphosphate-binding cassette (ABC)B1, ABCC1 and ABCG2 genes, respectively. Unlike other recognized chemoresistant leukemia cell lines, HL-60/RS cells were also strongly cross-resistant to arsenic trioxide. The proportion of leukemia stem cells (LSCs) increased synchronously with increased of drug resistance in the doxorubicin-induced HL-60 cell population. The present study confirmed that doxorubicin-induced HL-60 cells exhibited multidrug-resistance and high arsenic-trioxide resistance. Drug-resistance in these cells may be due to surviving chemoresistant LSCs in the HL-60 population, which have been subjected to long and consecutive selection by doxorubicin.

Resveratrol induces autophagic apoptosis via the lysosomal cathepsin D pathway in human drug-resistant K562/ADM leukemia cells.

The aim of the present study was to investigate the crosstalk between resveratrol (Res)-induced autophagy and apoptosis, and the molecular pathway by which autophagy leads to apoptotic death in drug-resistant K562/ADM leukemia cells. The viability of K562/ADM cells was determined using the MTT assay. The formation of autophagic vacuoles was detected using transmission electron microscopy and monodansylcadaverine (MDC) staining. Cell apoptosis was evaluated using flow cytometry. The expression of apoptosis- or autophagy-associated proteins was measured using western blotting. The results indicated that treatment with Res inhibited cell viability in a concentration-dependent manner. Furthermore, the numbers of MDC-positive fluorescent points, autophagic vacuoles and autolysosome-engulfed cytoplasmic materials were markedly increased in Res-treated K562/ADM cells compared with untreated cells, as determined using fluorescence microscopy and transmission electron microscopy. Res-induced apoptosis was associated with increased cleaved caspase-3 and B-cell lymphoma 2 associated X protein, and decreased B-cell lymphoma 2 (Bcl-2) protein expression levels when compared with the control (P<0.05). However, the proportion of apoptotic cells decreased from 69.6 to 41.0% (40 µmol/l Res) and from 77.3 to 58.8% (80 µmol/l Res) following pre-treatment with the autophagy inhibitor 3-methyladenine (P<0.01). The protein expression levels of microtubule-associated protein 1A/1B-light chain 3 and beclin 1, two markers of autophagy, were upregulated in Res-treated cells compared with the control (P<0.05). In addition, lysosomal cathepsin D (Cath D) release increased during Res-induced autophagy and apoptosis (P<0.05). The present results demonstrated that Res-induced apoptosis of K562/ADM cells was autophagy-dependent and the released Cath D may trigger caspase-dependent cell death through the Bcl-2 family of proteins. Furthermore, the present data indicate that to enhancement of the autophagy-cathepsin-apoptosis pathway may be an effective approach for overcoming anticancer drug resistance.

Beam splitter and router via an incoherent pump-assisted electromagnetically induced blazed grating.

We propose a scheme for a beam splitter and a beam router via an electromagnetically induced blazed grating in a four-level double-Λ system driven by an intensity-modulated coupling field and an incoherent pump field. The blazed grating relies on the incoherent pump process, which helps in inducing large refractivity with suppressed absorption or even gain. Consequently, the weak probe beam can be effectively deflected with high diffraction efficiency, and, meanwhile, its energy is amplified. When using an intensity mask with two symmetric domains in the coupling field, the presented blazed grating provides the possibility of a symmetric beam splitter. The diffraction efficiency and diffraction order of the gratings are sensitive to the intensity of the coupling field, and, thus, the gratings can function as a tunable asymmetric beam splitter or a beam router, which distributes the probe field into different spatial directions. Therefore, the proposed scheme may have potential applications in optical communication and networking.