Mitochondrial dysfunctions trigger the calcium signaling-dependent fungal multidrug resistance

Drug resistance in fungal pathogens has risen steadily over the past decades due to long-term azole therapy or triazole usage in agriculture. Modification of the drug target protein to prevent drug binding is a major recognized route to induce drug resistance. However, mechanisms for nondrug target-induced resistance remain only loosely defined. Here, we explore the molecular mechanisms of multidrug resistance resulted from an efficient adaptation strategy for survival in drug environments in the human pathogen Aspergillus fumigatus. We show that mutants conferring multidrug resistance are linked with mitochondrial dysfunction induced by defects in heme A biosynthesis. Comparison of the gene expression profiles between the drug-resistant mutants and the parental wild-type strain shows that multidrug-resistant transporters, chitin synthases, and calcium-signaling-related genes are significantly up-regulated, while scavenging mitochondrial reactive oxygen species (ROS)-related genes are significantly down-regulated. The up-regulated-expression genes share consensus calcium-dependent serine threonine phosphatase-dependent response elements (the binding sites of calcium-signaling transcription factor CrzA). Accordingly, drug-resistant mutants show enhanced cytosolic Ca2+ transients and persistent nuclear localization of CrzA. In comparison, calcium chelators significantly restore drug susceptibility and increase azole efficacy either in laboratory-derived or in clinic-isolated A. fumigatus strains. Thus, the mitochondrial dysfunction as a fitness cost can trigger calcium signaling and, therefore, globally up-regulate a series of embedding calcineurin-dependent–response-element genes, leading to antifungal resistance. These findings illuminate how fitness cost affects drug resistance and suggest that disruption of calcium signaling might be a promising therapeutic strategy to fight against nondrug target-induced drug resistance.

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Expression Profiles of microRNAs in Drug-Resistant Non-Small Cell Lung Cancer Cell Lines Using microRNA Sequencing

Cellular Physiology and Biochemistry ◽

10.1159/000495921 ◽

2018 ◽

Vol 51 (6) ◽

pp. 2509-2522 ◽

Cited By ~ 9

Author(s):

Shousen Hu ◽

Yongliang Yuan ◽

Zhizhen Song ◽

Dan Yan ◽

Xiangzhen Kong

Keyword(s):

Lung Cancer ◽

Drug Resistance ◽

Small Cell Lung Cancer ◽

Cell Lines ◽

Cell Lung Cancer ◽

Expression Profiles ◽

Small Cell ◽

Nsclc Cell ◽

Drug Resistant ◽

Small Cell Lung

Background/Aims: Drug resistance remains a main obstacle to the treatment of non- small cell lung cancer (NSCLC). The aim of this study was to identify the expression profiles of microRNAs (miRNAs) in drug-resistant NSCLC cell lines. Methods: The expression profiles of miRNAs in drug-resistant NSCLC cell lines were examined using miRNA sequencing, and the common dysregulated miRNAs in these cell lines were identified and analyzed by bioinformatics methods. Results: A total of 29 upregulated miRNAs and 36 downregulated miRNAs were found in the drug-resistant NSCLC cell lines, of which 26 upregulated and 36 downregulated miRNAs were found to be involved in the Ras signaling pathway. The expression levels, survival analysis, and receiver operating characteristic curve of the dysregulated miRNAs based on The Cancer Genome Atlas database for lung adenocarcinoma showed that hsa-mir-192, hsa-mir-1293, hsa-mir-194, hsa-mir-561, hsa-mir-205, hsa-mir-30a, and hsa-mir-30c were related to lung cancer, whereas only hsa-mir-1293 and hsa-mir-561 were not involved in drug resistance. Conclusion: The results of this study may provide novel biomarkers for drug resistance in NSCLC and potential therapies for overcoming drug resistance, and may also reveal the potential mechanisms underlying drug resistance in this disease.

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Analysis of ceRNA networks and identification of potential drug targets for drug-resistant leukemia cell K562/ADR

PeerJ ◽

10.7717/peerj.11429 ◽

2021 ◽

Vol 9 ◽

pp. e11429

Author(s):

Zhaoping Liu ◽

Yanyan Wang ◽

Zhenru Xu ◽

Shunling Yuan ◽

Yanglin Ou ◽

...

Keyword(s):

Drug Resistance ◽

Drug Targets ◽

Regulatory Networks ◽

Expression Profiles ◽

Leukemia Cell ◽

Gene Expression Profiles ◽

Leukemia Cells ◽

Mrna Levels ◽

Drug Resistant ◽

Cerna Network

Background Drug resistance is the main obstacle in the treatment of leukemia. As a member of the competitive endogenous RNA (ceRNA) mechanism, underlying roles of lncRNA are rarely reported in drug-resistant leukemia cells. Methods The gene expression profiles of lncRNAs and mRNAs in doxorubicin-resistant K562/ADR and sensitive K562 cells were established by RNA sequencing (RNA-seq). Expression of differentially expressed lncRNAs (DElncRNAs) and DEmRNAs was validated by qRT-PCR. The potential biological functions of DElncRNAs targets were identified by GO and KEGG pathway enrichment analyses, and the lncRNA-miRNA-mRNA ceRNA network was further constructed. K562/ADR cells were transfected with CCDC26 and LINC01515 siRNAs to detect the mRNA levels of GLRX5 and DICER1, respectively. The cell survival rate after transfection was detected by CCK-8 assay. Results The ceRNA network was composed of 409 lncRNA-miRNA pairs and 306 miRNA-mRNA pairs based on 67 DElncRNAs, 58 DEmiRNAs and 192 DEmRNAs. Knockdown of CCDC26 and LINC01515 increased the sensitivity of K562/ADR cells to doxorubicin and significantly reduced the half-maximal inhibitory concentration (IC50) of doxorubicin. Furthermore, knockdown of GLRX5 and DICER1 increased the sensitivity of K562/ADR cells to doxorubicin and significantly reduced the IC50 of doxorubicin. Conclusions The ceRNA regulatory networks may play important roles in drug resistance of leukemia cells. CCDC26/miR-140-5p/GLRX5 and LINC01515/miR-425-5p/DICER1 may be potential targets for drug resistance in K562/ADR cells. This study provides a promising strategy to overcome drug resistance and deepens the understanding of the ceRNA regulatory mechanism related to drug resistance in CML cells.

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The molecular mechanisms of multidrug resistance of human glioblastomas

Problems in oncology ◽

10.37469/0507-3758-2021-67-1-20-28 ◽

2021 ◽

Vol 67 (1) ◽

pp. 20-28

Author(s):

Alexandr Chernov ◽

Irina Baldueva ◽

Tatyana Nekhaeva ◽

Elvira Galimova ◽

Diana Alaverdian ◽

...

Keyword(s):

Signal Transduction ◽

Drug Resistance ◽

Transcription Factors ◽

Growth Factors ◽

Multidrug Resistance ◽

Tumor Suppressor Genes ◽

Molecular Mechanisms ◽

Molecular Targets ◽

Polymorphic Variants ◽

Signal Transduction Proteins

In review discusses the phenomenon of drug resistance of GB in the context of the expression of ABC family transporter proteins and the processes of proliferation, angiogenesis, recurrence and death. The emphasis is on the identifying for molecular targets among growth factors, receptors, signal transduction proteins, microRNAs, transcription factors, proto-oncogenes, tumor suppressor genes and their polymorphic variants (SNPs) for the development and creation of targeted anticancer drugs.

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Harnessing Gene Expression Profiles for the Identification of Ex Vivo Drug Response Genes in Pediatric Acute Myeloid Leukemia

Cancers ◽

10.3390/cancers12051247 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1247 ◽

Cited By ~ 1

Author(s):

David G.J. Cucchi ◽

Costa Bachas ◽

Marry M. van den Heuvel-Eibrink ◽

Susan T.C.J.M. Arentsen-Peters ◽

Zinia J. Kwidama ◽

...

Keyword(s):

Gene Expression ◽

Drug Resistance ◽

Drug Response ◽

Molecular Mechanisms ◽

Ex Vivo ◽

Expression Profiles ◽

Gene Expression Profiles ◽

Leukemic Cells ◽

Treatment Optimization ◽

Pediatric Aml

Novel treatment strategies are of paramount importance to improve clinical outcomes in pediatric AML. Since chemotherapy is likely to remain the cornerstone of curative treatment of AML, insights in the molecular mechanisms that determine its cytotoxic effects could aid further treatment optimization. To assess which genes and pathways are implicated in tumor drug resistance, we correlated ex vivo drug response data to genome-wide gene expression profiles of 73 primary pediatric AML samples obtained at initial diagnosis. Ex vivo response of primary AML blasts towards cytarabine (Ara C), daunorubicin (DNR), etoposide (VP16), and cladribine (2-CdA) was associated with the expression of 101, 345, 206, and 599 genes, respectively (p < 0.001, FDR 0.004–0.416). Microarray based expression of multiple genes was technically validated using qRT-PCR for a selection of genes. Moreover, expression levels of BRE, HIF1A, and CLEC7A were confirmed to be significantly (p < 0.05) associated with ex vivo drug response in an independent set of 48 primary pediatric AML patients. We present unique data that addresses transcriptomic analyses of the mechanisms underlying ex vivo drug response of primary tumor samples. Our data suggest that distinct gene expression profiles are associated with ex vivo drug response, and may confer a priori drug resistance in leukemic cells. The described associations represent a fundament for the development of interventions to overcome drug resistance in AML, and maximize the benefits of current chemotherapy for sensitive patients.

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DIGE-Based Proteomic Analysis Identifies NPM/B23 and Nucleolin C23 as Overexpressed Proteins In Relapsed /Refractory Acute Leukemia

Blood ◽

10.1182/blood.v116.21.1711.1711 ◽

2010 ◽

Vol 116 (21) ◽

pp. 1711-1711

Author(s):

Jian Da Hu ◽

MinHui Lin ◽

TingBo Liu ◽

Jing Li ◽

XinJi Chen ◽

...

Keyword(s):

Treatment Outcome ◽

Multidrug Resistance ◽

Acute Leukemia ◽

Western Blot ◽

Cell Lines ◽

Molecular Mechanisms ◽

Expression Profiles ◽

Leukemia Cell ◽

Leukemic Cell ◽

Leukemic Cell Lines

Abstract Abstract 1711 Resistance to chemotherapy is a challenge in treatment of acute leukemia. Although the classic multidrug resistance (MDR) phenotype is often characterized by expression of drug efflux pump P-glycoprotein or by multidrug resistance-associated proteins, precise molecular mechanisms are largely unknown. To investigate novel protein changes involved in resistance mechanism, protein expression profiles between human myeloid leukemia HL-60 cell lines and adriamycin- resistant HL-60 cell lines (HL-60/ADR) was compared, which was based on a differential proteomic approach — 2 dimensional difference in gel Electrophoresis(2D-DIGE) followed by mass spectrometry (MALDI-TOF-MS) and complemented by western blot validation. 16 protein spots were identified as being differentially expressed (> 1.2 fold change and p≤ 0.05) between above two cell lines, among which 13 protein spots were identified as up-regulated and 3 as down-regulated in the HL-60/ ADR cell line. Proteins found to have higher abundance levels in the resistant HL-60/ADR cells included enzymes, proteins and oncogenes related to signal transduction, protein synthesis, cell growth regulation and metabolism. 3 lower abundance proteins are related to transcription. From 16 proteins, 2 proteins, nucleophosmin B23 (NPM B23)and nucleolin C23, were selected and verified in leukemia cell lines and primary leukemia samples by western blot. Compared to healthy control samples, which showed no expressions of these 2 proteins, leukemic cell lines revealed an obvious up-regulation of B23 and C23. Moreover, significantly higher expressions of B23 and C23 were found in 3 resistant leukemic cell lines, HL-60/ADR, K562/ADR and KG01 cells, compared to the parent HL-60 and K562 cells, and other leukemic cell lines. In de novo leukemia samples, 43.8%(35/80) expressed B23 and C23 proteins, 37.9% (22/58) AML and 59.1% (13/22) ALL respectively. Meanwhile, concomitant expression of B23 and C23, both positive or negative, was noted in 97%(79/80)patients. Over-expressions of B23 and C23 were observed in 68.8% relapased/refractory leukemia patients. With regard to treatment outcome,among those patients who achieved ongoing CR, fewer patients expressed 2 proteins, only 13.35% (7/52) AML and 46%(7/15) ALL respectively. It implicated that B23 and C23 may be involved in drug resistance and be useful in assessing treatment outcome and prognosis of leukemia. To a conclusion, these results provide a novel clue for the molecular mechanism of MDR and suggest that B23 and C23 are prognostic indicators for leukemia. Disclosures: No relevant conflicts of interest to declare.

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Molecular Mechanism of DAPD/DXG against Zidovudine- and Lamivudine- Drug Resistant Mutants: A Molecular Modelling Approach

Antiviral Chemistry and Chemotherapy ◽

10.1177/095632020201300205 ◽

2002 ◽

Vol 13 (2) ◽

pp. 115-128 ◽

Cited By ~ 11

Author(s):

Youhoon Chong ◽

Katyna Borroto-Esoda ◽

Phillip A Furman ◽

Raymond F Schinazi ◽

Chung K Chu

Keyword(s):

Drug Resistance ◽

Amino Acid ◽

Antiviral Activity ◽

Molecular Mechanism ◽

Binding Affinity ◽

Molecular Modelling ◽

Enzyme Inhibitor ◽

Drug Resistant ◽

Amino Acid Residues ◽

Resistant Mutants

In order to understand molecular mechanism of antiviral drug resistance of HIV-1 reverse transcriptase (RT) as well as potent antiviral activity of 2,6-diaminopurine dioxolane (DAPD) [prodrug of (–)-β-D-dioxolane guanine (DXG)] against drug-resistant RTs, molecular modelling studies of three structurally distinct nucleoside RT inhibitor (NRTI)-triphosphates (TP) [zidovudine (AZT)-TP, lamivudine (3TC)-TP and DXG-TP] complexed with the wild-type (WT) and mutated RT were conducted. The computational analyses indicated that the antiviral activity and the calculated relative binding energy of the RT inhibitor triphosphates can be correlated, and the minimized structures gave information on the molecular mechanism of drug resistance conferred by mutations. The interactions between the NRTI-TP and adjacent amino acid residues (Lys65, Lys70, Arg72, Tyr115 and/or Gln151) played important roles in stabilizing the enzyme—inhibitor complex. Particularly, Arg72 was found to stabilize the dioxolane and oxathiolane sugar moiety through hydrogen bonding, which was responsible for favourable binding affinity of DXG-TP to AZT- as well as 3TC-resistant mutants. The conformational changes in these amino acid residues caused by mutation always affected the changes in the tertiary structures of enzyme-inhibitor complexes through either closing or opening the gap between the fingers and palm domains. The enzyme-inhibitor complexes with good binding affinity showed tight binding modes by closing the gap between the two domains, whereas weak inhibitors gave open and loose complexes.

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Two Lytic Bacteriophages That Depend on theEscherichia coliMulti-Drug Efflux GenetolCand Differentially Affect Bacterial Growth and Selection

10.1101/397695 ◽

2018 ◽

Cited By ~ 2

Author(s):

Alita R. Burmeister ◽

Rose G. Bender ◽

Abigail Fortier ◽

Adam J. Lessing ◽

Benjamin K. Chan ◽

...

Keyword(s):

Drug Resistance ◽

Antibiotic Resistance ◽

Resistance Gene ◽

Bacterial Growth ◽

Bacterial Pathogens ◽

Antibiotic Resistance Gene ◽

Resistant Bacteria ◽

Drug Efflux ◽

Drug Resistant ◽

Resistant Mutants

AbstractBacterial pathogens are increasingly evolving drug resistance under natural selection from antibiotics in medicine, agriculture, and nature. Meanwhile, bacteria ubiquitously encounter bacteriophages and can rapidly evolve phage resistance. However, the role of phages in interacting with drug-resistant and drug-sensitive bacteria remains unclear. To gain insight into such relationships, we screened for and characterized phages that rely on the multi-drug efflux pump genetolC. First, we screened a collection of 33 environmental and commercialEscherichia coliphages for their ability to infect cells that lackedtolC. Our screen revealed two phages that had reduced efficiency of plating (EOP) on thetolCknockout compared to wild type. We further characterized these phages with bacterial growth curves, transmission electron microscopy, and analysis of phage-resistant mutants. Phage U136B is a curly-tailed virus in familySiphoviridaewith no ability to infect atolCknockout, suggesting TolC is the U136B receptor. Phage 132 is a contractile-tailed virus in familyMyoviridaewith reduced EOP on cells lackingompFand its positive regulatorstolCandompR. U136B and 132 differentially effect bacterial growth and lysis, and U136B-resistant mutants contain mutations of thetolCgene. Together, these results show that thetolCgene involved in drug resistance can modify bacteria-phage interactions in multiple ways, altering bacterial lysis and selection. These new phages offer utility for studying evolution, tradeoffs, and infection mechanisms.ImportanceBacteria face strong selection by antibiotics in medicine and agriculture, resulting in increasing levels of drug resistance among bacterial pathogens. Slowing this process will require an understanding of the environmental contexts in which drug resistance evolutionarily increases or decreases. In this study, we investigate two newly-isolated bacteriophages that rely on a bacterial antibiotic resistance gene. These bacteriophages vary in their interactions with drug-resistant bacteria, with one of the phages selecting for phage-resistant mutants that have mutations in the antibiotic resistance gene. Further study of these new phages will be useful to understanding evolutionary tradeoffs and how phages might be applied in natural settings to reverse the problem of drug resistance.

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Deciphering complex mechanisms of resistance and loss of potency through coupled molecular dynamics and machine learning.

10.1101/2020.06.08.139105 ◽

2020 ◽

Author(s):

Florian Leidner ◽

Nese Kurt-Yilmaz ◽

Celia A Schiffer

Keyword(s):

Machine Learning ◽

Molecular Dynamics ◽

Drug Resistance ◽

Active Site ◽

Molecular Mechanisms ◽

Learning Strategy ◽

Drug Binding ◽

Feature Reduction ◽

Rigorous Model ◽

Dynamics Simulations

Drug resistance threatens many critical therapeutics through mutations in the drug target. The molecular mechanisms by which combinations of mutations, especially involving those distal from the active site, alter drug binding to confer resistance are poorly understood and thus difficult to counteract. A machine learning strategy was developed that couples parallel molecular dynamics simulations and experimental potency to identify specific conserved mechanisms underlying resistance. A series of 28 HIV-1 protease variants with 0-24 substitutions each were used as a rigorous model of this strategy. Many of the mutations were distal from the active site and the potency of variants to a drug (darunavir) varied from low picomolar to near micromolar. With features extracted from the simulations, elastic network machine learning was applied to correlate physical interactions with loss of potency and succeeded to within 1 kcal/mol of experimental affinity for both the training and test sets, outperforming MM/GBSA calculations. Feature reduction resulted in a model with 4 specific features that describe interactions critical for potency for all 28 variants. These predictive features, that specifically vary with potency, occur throughout the enzyme and would not have been identified without dynamics and machine learning. This strategy thus captures the conserved dynamic mechanisms by which complex combinations of mutations confer resistance and identifies critical features that serve as bellwethers of loss of inhibitor potency. Machine learning models leveraging molecular dynamics can thus elucidate mechanisms of drug resistance that confer loss of affinity and will serve as predictive tools in future drug design.

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Chalcone derivatives and their activities against drug-resistant cancers: An overview

Current Topics in Medicinal Chemistry ◽

10.2174/1568026620666201022143236 ◽

2020 ◽

Vol 20 ◽

Author(s):

Jiaqi Xiao ◽

Meixiang Gao ◽

Qiang Diao ◽

Feng Gao

Keyword(s):

Drug Resistance ◽

Multidrug Resistance ◽

Cancer Cells ◽

Anticancer Agents ◽

Rational Design ◽

Multidrug Resistant ◽

Drug Resistant ◽

Chalcone Derivatives ◽

Potential Activity ◽

Defensive Mechanisms

: Drug resistance including multidrug resistance resulting from different defensive mechanisms in cancer cells is the leading cause of the failure about the cancer therapy, making it an urgent need to develop more effective anticancer agents. Chalcones, widely distributed in nature, could act on diverse enzymes and receptors in cancer cells. Accordingly, chalcone derivatives possess potential activity against various cancers including drug-resistant even multidrug-resistant cancer. This review outlines the recent development of chalcone derivatives with potential activity against drug-resistant cancers covering articles published between 2010 and 2020, so as to facilitate further rational design of more effective candidate.

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