MiR-330-3p suppresses phosphoglycerate mutase family member 5 -inducted mitophagy to alleviate hepatic ischemia-reperfusion injury.

Mitochondrial dysfunction plays a central role in hepatic ischemia-reperfusion injury (IRI). The significance of mitophagy in hepatic IRI remains poorly understood. The mechanisms that cause IRI are complex, and many factors are involved in the injury formation process. The miR-330-3p mediates cell proliferation, cell death, and metabolism in various organisms. In this study, the levels of miR-330-3p were significantly downregulated in hepatic IRI, and the number of autophagosomes was increased in response to IRI as obtained under both in vivo and in vitro conditions. These results demonstrate that a reduction in miR-330-3p expression represents an important factor involved with promoting hepatic IRI. Moreover, we found that miR-330-3p interacted with phosphoglycerate mutase family member 5 (PGAM5) to regulate mitophagy. In specific, an overexpression of miR-330-3p diminished PGAM5 levels, which promoted mitophagy in response to IRI. In contrast, a downregulation of miR-330-3p was associated with increased PGAM5 levels leading to increased mitophagy. In conclusion, miR-330-3p suppresses PGAM5-induced mitophagy to alleviate hepatic IRI. Such findings not only reveal some of the mechanistic basis for this microRNA in liver injury, but also provide a foundation for new therapeutic approaches in the treatment of this condition.

Establishment and characterization of a novel childhood acute lymphoblastic leukemia cell line, HXEX-ALL1, with chromosome 9p and 17p deletions.

BACKGROUND: Although contemporary chemotherapy has improved the cure rate of childhood acute lymphoblastic leukemia (ALL) to nearly 90%, relapsed/refractory ALL is still a leading cause of tumor-related death in children. To clarify the underlying mechanisms of relapsed/refractory childhood ALL, researchers urgently need to establish novel cell models from patients with relapsed ALL after treatment with contemporary chemotherapy. METHODS: Cell culture technique was used to establish the HXEX-ALL1 cell line from primary B cell precursor ALL (BCP-ALL) cells. Molecular and cellular biological techniques including flow cytometry, polymerase chain reaction (PCR), short tandem repeat (STR) analysis, conventional cytogenetics, and chromosomal microarray analysis (CMA) were used to characterize the HXEX-ALL1 cell line. Nude mice were used for xenograft studies. RESULTS: A stable ALL cell line, HXEX-ALL1, derived from a 6-year-old boy of Han nationality with BCP-ALL at the second relapse, was established and maintained in culture for more than 18 months. The HXEX-ALL1 cell line was authenticated as being derived from primary leukemia cells based on morphologic, immunophenotypic, cytogenetic and STR analyses and demonstrated tumorigenicity in nude mice. WGS data showed that there were 27,006 novel single nucleotide polymorphisms (SNPs) and 193,951 novel insertion/deletions (InDels) in HXEX-ALL1 cells. Compared with the other BCP-ALL cell lines in use, the HXEX-ALL1 cells have a special karyotype represented by trisomy 8 and 9p and 17p deletions with a multidrug resistance phenotype, especially highly resistant to asparaginase. CONCLUSIONS: The HXEX-ALL1 cell line may prove to be a useful model for the study of relapsed/refractory childhood ALL, particularly for the researches on asparaginase resistance.

Targeting mTOR/p70S6K/glycolysis signaling pathway restores glucocorticoid sensitivity to 4E-BP1 null Burkitt Lymphoma.

BACKGROUND: Increasing evidence indicates that rapamycin could be used as a potential glucocorticoid (GC) sensitizer in lymphoblastic malignancies via genetic prevention of 4E-BP1 phosphorylation. Interestingly, we found that combined rapamycin with dexamethasone can effectively reverse GC resistance in 4E-BP1 null lymphoma cells. In this study, we investigated the potential link between mTOR/p70S6K signaling pathway, glycolysis, autophagy and GC resistance. METHODS: Antitumor effects of the combination of rapamycin and dexamethasone were evaluated on cell viability by MTT assay and in vivo studies, on cell cycle and apoptosis by flow cytometry, on autophagy by western blot, MDC staining and transmission electron microscopy and on cell signaling by western blot. Moreover, to test whether inhibiting glycolysis is the core mechanism in rapamycin restoring GC sensitivity, we took glycolysis inhibitor 2-deoxyglucose to replace rapamycin and then evaluated the antitumor effects in vitro. RESULTS: Raji cells are resistant to rapamycin (IC50 > 1000 nM) or dexamethasone (IC50 > 100 µM) treatment alone. The combination of rapamycin and dexamethasone synergistically inhibited the viability of Raji cells in vitro and in vivo by inducing caspase-dependent and -independent cell death and G0/G1 cell cycle arrest. These effects were achieved by the inhibition of mTOR/p70S6K signaling pathway, which led to the inhibition of glycolysis and the induction of autophagy. Pretreatment with pan-caspase inhibitor z-VAD-fmk or autophagy inhibitor 3-MA failed to protect the cells from combined treatment-induced death. Glycolysis inhibitor combined with dexamethasone produced a similar antitumor effects in vitro. CONCLUSIONS: Inhibition of mTOR/p70S6K/glycolysis signaling pathway is the key point of therapy in reversing GC resistant in Burkitt lymphoma patients.

Prognostic significance and therapeutic potential of the activation of anaplastic lymphoma kinase/protein kinase B/mammalian target of rapamycin signaling pathway in anaplastic large cell lymphoma.

BACKGROUND: Activation of the protein kinase B/mammalian target of rapamycin (AKT/mTOR) pathway has been demonstrated to be involved in nucleophosmin-anaplastic lymphoma kinase (NPM-ALK)-mediated tumorigenesis in anaplastic large cell lymphoma (ALCL) and correlated with unfavorable outcome in certain types of other cancers. However, the prognostic value of AKT/mTOR activation in ALCL remains to be fully elucidated. In the present study, we aim to address this question from a clinical perspective by comparing the expressions of the AKT/mTOR signaling molecules in ALCL patients and exploring the therapeutic significance of targeting the AKT/mTOR pathway in ALCL. METHODS: A cohort of 103 patients with ALCL was enrolled in the study. Expression of ALK fusion proteins and the AKT/mTOR signaling phosphoproteins was studied by immunohistochemical (IHC) staining. The pathogenic role of ALK fusion proteins and the therapeutic significance of targeting the ATK/mTOR signaling pathway were further investigated in vitro study with an ALK + ALCL cell line and the NPM-ALK transformed BaF3 cells. RESULTS: ALK expression was detected in 60% of ALCLs, of which 79% exhibited the presence of NPM-ALK, whereas the remaining 21% expressed variant-ALK fusions. Phosphorylation of AKT, mTOR, 4E-binding protein-1 (4E-BP1), and 70 kDa ribosomal protein S6 kinase polypeptide 1 (p70S6K1) was detected in 76%, 80%, 91%, and 93% of ALCL patients, respectively. Both phospho-AKT (p-AKT) and p-mTOR were correlated to ALK expression, and p-mTOR was closely correlated to p-AKT. Both p-4E-BP1 and p-p70S6K1 were correlated to p-mTOR, but were not correlated to the expression of ALK and p-AKT. Clinically, ALK + ALCL occurred more commonly in younger patients, and ALK + ALCL patients had a much better prognosis than ALK-ALCL cases. However, expression of p-AKT, p-mTOR, p-4E-BP1, or p-p70S6K1 did not have an impact on the clinical outcome. Overexpression of NPM-ALK in a nonmalignant murine pro-B lymphoid cell line, BaF3, induced the cells to become cytokine-independent and resistant to glucocorticoids (GCs). Targeting AKT/mTOR inhibited growth and triggered the apoptotic cell death of ALK + ALCL cells and NPM-ALK transformed BaF3 cells, and also reversed GC resistance induced by overexpression of NPM-ALK. CONCLUSIONS: Overexpression of ALK due to chromosomal translocations is seen in the majority of ALCL patients and endows them with a much better prognosis. The AKT/mTOR signaling pathway is highly activated in ALK + ALCL patients and targeting the AKT/mTOR signaling pathway might confer a great therapeutic potential in ALCL.

Computerized mediated explicit instruction and EFL learners' knowledge of speech acts: Investigating the role of EFL learners' language proficiency and perceptions.

Computer-mediated explicit Instruction (CMEI) is effective in promoting second language development, particularly in the area of speech acts. However, more information is needed about the role of learners' language proficiency and perceptions in the effectiveness of CMEI. This study aimed to investigate the effect of CMEI on EFL learners' knowledge of speech acts, specifically apologies, thanks, and requests, and to examine the moderating role of language proficiency and learners' perceptions of the Instruction. A mixed-method research design was used. The study involved 180 EFL learners who were recruited from Wenzhou Medical University. The participants were randomly assigned to one of three groups: (1) the computer-mediated explicit instruction (CMEI) group, which received explicit Instruction on speech acts through a computer program; (2) the non-CMEI group, which received explicit Instruction on speech acts through traditional classroom instruction; and (3) Control group, which did not receive any explicit instruction on speech acts. The participants' language proficiency was assessed using the Oxford Quick Placement Test (OQPT) prior to the intervention. The quantitative phase employed the pretest-posttest design, and data were collected using a speech act recognition and production test and an interview checklist to measure learners' perceptions of the Instruction. Results showed that CMEL was more effective than non-CMEI. Participants also had positive perceptions of CMEI. Findings have theoretical and practical implications for English language teachers and applied linguists.

A novel method to establish glucocorticoid resistant acute lymphoblastic leukemia cell lines.

BACKGROUND: Drug-resistant cell lines, established from drug-sensitive cell lines by drug exposure in vitro, are the most useful cancer models in studies on the mechanism of chemoresistance. However, the success rate of the traditional approaches to construct such cell lines is low because a long time is required for the addition of drugs. METHODS: A cell culture technique was used to establish the drug-resistant cell lines from their parental cells. Molecular and cellular biological techniques including flow cytometry, MTT assay, western blotting, and DNA fingerprinting analysis were used to characterize the drug-resistant cell lines. Nude mice were used for xenograft studies. RESULTS: We established novel glucocorticoid (GC)-resistant cell lines from 3 GC-sensitive acute lymphoblastic leukemia (ALL) cell lines. First, we established a novel GC-resistant T-ALL cell line, CEM-C7/HDR, by mimicking the microenvironment of the bone marrow and culturing GC-sensitive CEM-C7-14 cells under hypoxia for 5 weeks with a single dexamethasone (Dex) treatment. The CEM-C7/HDR cells had been cultured continuously in drug-free medium under normoxia for 1 year. The IC50 and resistance index (RI) to Dex were maintained at 60~70 µM and 1500~1800, respectively, which is in consistent with the IC50 and RI of GC-resistant CEM-C1-15 cells. To clarify the reliability of the method, we subcloned CEM-C7-14 cells, and obtained Dex-resistant cell lines, CEM-C7-SC2/HDR and CEM-C7-SC14/HDR, from 2 monoclonal cells of CEM-C7-14 by the same method. Moreover, we obtained two additional Dex-resistant B-ALL cell lines, NALM-6/HDR and HXEX-ALL1/HDR, from NALM-6 and HXEX-ALL1 cells with the same approach. CONCLUSIONS: CEM-C7/HDR, NALM-6/HDR and HXEX-ALL1/HDR cell lines may serve as useful GC-resistant ALL models for both in vitro and in vivo studies. Culturing under hypoxic condition with a single Dex treatment is a novel and convenient approach for generating stable GC resistant cell lines.

Upregulation of lncRNA HAGLROS enhances the development of nasopharyngeal carcinoma via modulating miR-100/ATG14 axis-mediated PI3K/AKT/mTOR signals.

We planned to dig the significant role of long noncoding RNA HAGLROS in nasopharyngeal carcinoma (NPC) and the latent mechanism. The levels of HAGLROS in NPC tissues and cells were determined, followed by correlation analysis of HAGLROS level and clinicopathological features of patients suffered with NPC. The impacts of HAGLROS dysregulation on NPC cell viability, apoptosis, and the expression of apoptotic proteins and autophagy-related symbols were investigated. Moreover, we explored whether HAGLROS modulated the expression of autophagy-related gene 14 (ATG14) by competitively sponging miR-100, and then regulated the briskness of PI3K/AKT/mTOR signals in NPC development. HAGLROS level in NPC tissues and cell was very high. High level of HAGLROS indicated a short overall survival in NPC patients. Depressing of HAGLROS lessened NPC cell viability, enhanced apoptosis and reduced autophagy. Besides, HAGLROS negative controlled miR-100 and consequently targeted ATG14 expression, thus modulating NPC cell viability, apoptosis, and autophagy. Besides, dysregulation of HAGLROS/miR-100/ATG14 axis was correlated to the briskness of PI3K/AKT/mTOR signals in NPC cells. Our results indicate that of the augment of HAGLROS contributes to NPC development via modulating miR-100/ATG14 axis-mediated PI3K/AKT/mTOR signals. Our study will offer a comprehensive basis for better illustrating the pathogenesis of NPC. Highlights HAGLROS expression was upregulated in NPC tissues and cells. High expression of HAGLROS indicated a short overall survival in NPC patients. Silencing of HAGLROS promoted apoptosis and inhibited autophagy of NPC cells. HAGLROS regulated ATG14 expression in NPC cells via sponging miR-100. HAGLROS/miR-100/ATG14 axis regulated NPC development via PI3K/AKT/mTOR pathway.

Association between MnSOD Val16Ala Polymorphism and Cancer Risk: Evidence from 33,098 Cases and 37,831 Controls.

Manganese superoxide dismutase (MnSOD) plays a critical role in the defense against reactive oxygen species. The association between MnSOD Val16Ala polymorphism and cancer risk has been widely studied, but the results are contradictory. To obtain more precision on the association, we performed the current meta-analysis with 33,098 cases and 37,831 controls from 88 studies retrieved from PubMed, Embase, Chinese National Knowledge Infrastructure (CNKI), and Wanfang databases. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of association. We found that the polymorphism was associated with an increased overall cancer risk (homozygous: OR = 1.09, 95% CI = 1.00-1.19; heterozygous: OR = 1.07, 95% CI = 1.02-1.12; dominant: OR = 1.08, 95% CI = 1.02-1.14; and allele comparison: OR = 1.06, 95% CI = 1.02-1.11). Stratification analysis further showed an increased risk for prostate cancer, Asians, Caucasians, population-based studies, hospital-based studies, low quality and high quality studies. However, the increased risk for MnSOD Val16Ala polymorphism among Asians needs further validation based on the false-positive report probability (FPRP) test. To summarize, this meta-analysis suggests that the MnSOD Val16Ala polymorphism is associated with significantly increased cancer risk, which needs further validation in single large studies.

Acute Lymphoblastic Leukemia Patient with Variant ATF7IP/PDGFRB Fusion and Favorable Response to Tyrosine Kinase Inhibitor Treatment: A Case Report.

BACKGROUND Chromosomal translocations involving the PDGFRB gene have been reported in a broad spectrum of hematological malignancies. An ATF7IP/PDGFRB fusion was recently identified in a Philadelphia chromosome-like (Ph-like) B-progenitor acute lymphoblastic leukemia (B-ALL) patient. Here we report on a special case of a Ph-like ALL patient who had a variant ATF7IP/PDGFRB fusion. CASE REPORT In this case, a variant fusion was created between ATF7IP exon 9 (instead of exon 13) and PDGFRB exon 11, resulting in the loss of 411 nucleotides and 137 amino acids in the ATF7IP/PDGFRB fusion cDNA and its encoded chimeric protein, respectively. Interestingly, ATF7IP has also been reported as a fusion partner of the JAK2 kinase gene in Ph-like ALL, but all of the genomic breakpoints in ATF7IP in this fusion reported thus far occurred in intron 13. Enforced expression of the variant ATF7IP/PDGFRB fusion induced cytokine-independent growth and glucocorticoid resistance of BaF3 cells. Similar to the initially described ATF7IP/PDGFRB-bearing Ph-like ALL patient who was refractory to conventional chemotherapy but highly sensitive to tyrosine kinase inhibitor (TKI) monotherapy, our patient with a variant ATF7IP/PDGFRB fusion had a poor initial treatment response to chemotherapy but responded well to TKI-based therapy and is now doing well in continuous remission. CONCLUSIONS Ph-like ALL patient with an ATF7IP/PDGFRB fusion is rare, but can benefit from TKI therapy.

Low dose of 2-deoxy-D-glucose kills acute lymphoblastic leukemia cells and reverses glucocorticoid resistance via N-linked glycosylation inhibition under normoxia.

Recent studies showed that 2-deoxy-D-glucose (2-DG), a glucose analog with dual activity of inhibiting glycolysis and N-linked glycosylation, can be selectively taken up by cancer cells and be used as a potential chemo- and radio-sensitizer. Meanwhile, 2-DG can kill cancer cells under normoxia. However, its efficacy is limited by the high-dose induced systemic toxicity. Here, we showed that low-dose 2-DG could be used as a single agent to kill acute lymphoblastic leukemia (ALL) cells, and as a GC sensitizer to overcome GC resistance under normoxia. Addition of exogenous mannose, a sugar essential for N-linked glycosylation, rescued 2-DG-treated ALL cells, indicating that inhibition of N-linked glycosylation and induction of endoplasmic reticulum stress is the main mechanism for 2-DG to induce cell death and reverse GC resistance in ALL cells. These data provides new insight into the molecular mechanisms involved in GC resistance. More important, it indicates that 2-DG might be the promising drug for designing novel high efficiency and low toxic protocol for ALL patients.

Antileukemia Effect of Ciclopirox Olamine Is Mediated by Downregulation of Intracellular Ferritin and Inhibition ß-Catenin-c-Myc Signaling Pathway in Glucocorticoid Resistant T-ALL Cell Lines.

Ciclopirox olamine (CPX) is an antifungal drug that has been reported to have antitumor effects. In this study we investigated the antileukemia effects and the possible mechanisms of CPX on glucocorticoid (GC)-resistant T-cell acute lymphoblastic leukemia (T-ALL) cell lines. The results indicated that CPX inhibited the growth of GC-resistant T-ALL cells in a time- and dose-dependent manner, and this effect was closely correlated with the downregulation of intracellular ferritin. CPX induced cell cycle arrest at G1 phase by upregulation of cyclin-dependent kinase (CDK) inhibitor of p21 and downregulation of the expressions of cyclin D, retinoblastoma protein (Rb), and phosphorylated Rb (pRb). CPX also enhanced apoptotic cell death by downregulation of anti-apoptotic proteins such as Bcl-2, Bcl-xL, and Mcl-1. More importantly, CPX demonstrated a strong synergistic antileukemia effect with GC and this effect was mediated, at least in part, by inhibition of the ß-catenin-c-Myc signaling pathway. These findings suggest that CPX could be a promising antileukemia drug, and modulation of the intracellular ferritin expression might be an effective method in the treatment of ALL. Therefore, integrating CPX into the current GC-containing ALL protocols could lead to the improvement of the outcome of ALL, especially GC-resistant ALL.