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Since nuclear factor (NF) κB plays pivotal roles in inflammation and cancer, understanding its regulation holds great promise for disease therapy. Using the powerful validation-based insertional mutagenesis (VBIM) technique established by us previously, we discovered armadillo repeat-containing protein 4 (ARMC4)/outer dynein arm docking complex subunit 2 (ODAD2), a rarely studied protein known to date, as a novel negative regulator of NF-κB in colorectal cancer (CRC). High expression of ARMC4 downregulated the expression of NF-κB-dependent genes, dramatically reduced NF-κB activity, cellular proliferation, anchorage-independent growth, and migratory ability in vitro, and significantly decreased xenograft tumor growth in vivo. Co-immunoprecipitation experiments demonstrated that ARMC4 forms a complex with NF-κB. Importantly, the lower ARMC4 expression in patient tumors than normal tissues indicates its potential tumor suppressor function in CRC. Collectively, we uncovered a completely new facet of ARMC4 function by identifying it as a novel NF-κB negative regulator, thus uncovering ARMC4 as a potential new therapeutic target in CRC.
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Neoplasias Colorretais , NF-kappa B , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Humanos , Mutagênese Insercional , NF-kappa B/metabolismoRESUMO
The overexpression of PRMT5 is highly correlated to poor clinical outcomes for colorectal cancer (CRC) patients. Importantly, our previous work demonstrated that PRMT5 overexpression could substantially augment activation of the nuclear factor kappa B (NF-κB) via methylation of arginine 30 (R30) on its p65 subunit, while knockdown of PRMT5 showed the opposite effect. However, the precise mechanisms governing this PRMT5/NF-κB axis are still largely unknown. Here, we report a novel finding that PRMT5 is phosphorylated on serine 15 (S15) in response to interleukin-1ß (IL-1ß) stimulation. Interestingly, we identified for the first time that the oncogenic kinase, PKCι could catalyze this phosphorylation event. Overexpression of the serine-to-alanine mutant of PRMT5 (S15A), in either HEK293 cells or CRC cells HT29, DLD1, and HCT116 attenuated NF-κB transactivation compared to WT-PRMT5, confirming that S15 phosphorylation is critical for the activation of NF-κB by PRMT5. Furthermore, the S15A mutant when compared to WT-PRMT5, could downregulate a subset of IL-1ß-inducible NF-κB-target genes which correlated with attenuated promoter occupancy of p65 at its target genes. Additionally, the S15A mutant reduced IL-1ß-induced methyltransferase activity of PRMT5 and disrupted the interaction of PRMT5 with p65. Furthermore, our data indicate that blockade of PKCι-regulated PRMT5-mediated activation of NF-κB was likely through phosphorylation of PRMT5 at S15. Finally, inhibition of PKCι or overexpression of the S15A mutant attenuated the growth, migratory, and colony-forming abilities of CRC cells compared to the WT-PRMT5. Collectively, we have identified a novel PKCι/PRMT5/NF-κB signaling axis, suggesting that pharmacological disruption of this pivotal axis could serve as the basis for new anti-cancer therapeutics.
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Neoplasias Colorretais/metabolismo , NF-kappa B/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Transdução de Sinais , Substituição de Aminoácidos , Proliferação de Células , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Fosforilação , Proteína Quinase C/metabolismo , Proteína-Arginina N-Metiltransferases/química , Proteína-Arginina N-Metiltransferases/genética , Serina/genética , Serina/metabolismoRESUMO
BACKGROUND & OBJECTIVES: Leishmania (L.) infantum is the principal agent of visceral leishmaniasis (VL) in the Mediterranean and American regions. So far different molecular methods including high resolution melting (HRM) analysis have been developed for detecting and identifying L. infantum infection. HRM assay is an automted molecular method which detects and identifies different genus and species of infectious agents. This study aimed to diagnose and identify Leishmania infection caused by L. infantum species using real-time PCR coupled with HRM assay in the serum samples in comparison with anti-L. infantum antibodies obtained using direct agglutination test (DAT), in domestic and wild canines of northeastern Iran. METHODS: Serum samples of 15 foxes, 14 jackals, seven domestic dogs and three wolves were collected in some villages around Shirvan and Bojnourd districts from the northeast regions of Iran during 2014-15. Initially, all the collected serum samples were tested by DAT for the detection of anti-L. infantum antibodies. Afterwards, genomic DNA was extracted from the samples and tested by real-time PCR-HRM analysis targeting hsp70, ITS1 and gp63 genes. The level of agreement between DAT and HRM assay were analysed statistically. RESULTS: Out of the 39 serum samples, eight showed anti-L. infantum antibodies at titre 1: 80 while only one of them showed anti-L. infantum antibodies at titre 1 : 160. All the nine seropositive samples showed positive results with HRM analysis. Additionally, three DAT negative serum samples were also found positive in the HRM technique. Altogether, 12 out of the 39 DNA samples showed positive results in HRM analysis. Among the three gene sequences used, gp63 was best for separation and identification of species. INTERPRETATION & CONCLUSION: HRM analysis targeting hsp70, ITS1 and gp63 genes can be used as a highly sensitive technique for the screening and early detection of L. infantum infection in the wild and domestic canines. It has higher accuracy than DAT and allows detection and discrimination of different Leishmania species responsible for the Leishmaniases.
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Doenças do Cão/diagnóstico , Leishmania infantum/genética , Leishmaniose Visceral/veterinária , Reação em Cadeia da Polimerase em Tempo Real/métodos , Testes de Aglutinação , Animais , Anticorpos Antiprotozoários/sangue , DNA Intergênico/genética , DNA de Cinetoplasto/genética , DNA de Protozoário/sangue , Confiabilidade dos Dados , Reservatórios de Doenças , Doenças do Cão/parasitologia , Cães , Proteínas de Choque Térmico HSP70/genética , Irã (Geográfico) , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/diagnóstico , Metaloendopeptidases/genética , Temperatura de TransiçãoRESUMO
OBJECTIVES: The pathophysiology of recurrent laryngeal nerve (RLN) transection injury is rare in that it is characteristically followed by a high degree of spontaneous reinnervation, with reinnervation of the laryngeal adductor complex (AC) preceding that of the abducting posterior cricoarytenoid (PCA) muscle. Here, we aim to elucidate the differentially expressed myogenic factors following RLN injury that may be at least partially responsible for the spontaneous reinnervation. METHODS: F344 male rats underwent RLN injury (n = 12) or sham surgery (n = 12). One week after RLN injury, larynges were harvested following euthanasia. The mRNA was extracted from PCA and AC muscles bilaterally, and microarray analysis was performed using a full rat genome array. RESULTS: Microarray analysis of denervated AC and PCA muscles demonstrated dramatic differences in gene expression profiles, with 205 individual probes that were differentially expressed between the denervated AC and PCA muscles and only 14 genes with similar expression patterns. CONCLUSIONS: The differential expression patterns of the AC and PCA suggest different mechanisms of reinnervation. The PCA showed the gene patterns of Wallerian degeneration, while the AC expressed the gene patterns of reinnervation by adjacent axonal sprouting. This finding may reveal important therapeutic targets applicable to RLN and other peripheral nerve injuries.
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Músculos Laríngeos/inervação , Regeneração Nervosa/fisiologia , Traumatismos do Nervo Laríngeo Recorrente/fisiopatologia , Transcriptoma , Animais , Masculino , Análise em Microsséries , Modelos Animais , Ratos Endogâmicos F344 , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Hydatid cyst caused by Echinococcus granulosus is one of the most important parasitic diseases around the world and many countries in Asia, including Iran, are involved with this infection. This disease can cause high mortality in humans as well as economic losses in livestock. To date, several molecular methods have been used to determine the genetic diversity of E. granulosus. So far, identification of E. granulosus using real-time PCR fluorescence-based quantitative assays has not been studied worldwide, also in Iran. Therefore, the aim of this study was to investigate the genetic diversity of E. granulosus from center of Iran using real-time PCR method. A total of 71 hydatid cysts were collected from infected sheep, goat, and cattle slaughtered in Isfahan, Iran during 2013. DNA was extracted from protoscolices and/or germinal layers from each individual cyst and used as template to amplify the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) (420 bp). Five cattle isolates out of 71 isolates were sterile and excluded from further investigation. Overall, of 66 isolates, partial sequences of the cox1 gene of E. granulosus indicated the presence of genotypes G1 in 49 isolates (74.2%), G3 in 15 isolates (22.7%), and G6 in 2 isolates (3.0%) in infected intermediate hosts. Sixteen sequences of G1 genotype had microgenetic variants, and they were compared to the original sequence of cox1. However, isolates identified as G3 and G6 genotypes were completely consistent with original sequences. G1 genotype in livestock was the dominant genotype in Isfahan region, Iran.
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Equinococose/veterinária , Echinococcus granulosus/classificação , Echinococcus granulosus/genética , Variação Genética , Animais , Bovinos , Análise por Conglomerados , DNA de Helmintos/química , DNA de Helmintos/genética , Equinococose/parasitologia , Echinococcus granulosus/isolamento & purificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genótipo , Cabras , Irã (Geográfico) , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , OvinosRESUMO
INTRODUCTION: Raw milk is a nutrient-rich food, but it may harbour harmful bacteria, such as enterotoxigenic Staphylococcus aureus (S. aureus), which can cause staphylococcal food poisoning. Antibiotic resistance of S. aureus in raw milk can increase the risk of such infections, particularly among susceptible individuals. OBJECTIVE: This study aimed to investigate the prevalence of enterotoxin genes a, d, g, i and j and the antibiotic resistance of S. aureus isolated from raw milk samples. METHODS: During a 6-month sampling period, 60 raw milk specimens were obtained from diverse locations in Yazd province, Iran. Antibiogram profiling was conducted via the disc diffusion method. In addition, staphylococcal enterotoxin (SE) genes a, d, g, i, and j were detected through real-time PCR analysis. RESULTS: Bacteriological assays confirmed the presence of S. aureus in 11 samples (18.3%). All isolates demonstrated 100% resistance to penicillin G but exhibited sensitivity to vancomycin, while resistance to other antibiotics ranged from 36.4% to 45.5%. The prevalence of enterotoxin genes in these strains showed variable distribution, with sea being the predominant SE (45.5%), followed by sed (36.4%), seg (18.2), sej and sei (9.1% each). CONCLUSIONS: This study discovered the presence of multiple enterotoxins in S. aureus strains obtained from raw milk samples. These strains also demonstrated resistance to a variety of antibiotics. Since enterotoxigenic S. aureus is known to cause human food poisoning, monitoring food hygiene practices, especially during raw milk production, is critical.
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Enterotoxinas , Infecções Estafilocócicas , Humanos , Animais , Enterotoxinas/genética , Enterotoxinas/análise , Staphylococcus aureus/genética , Leite/microbiologia , Irã (Geográfico)/epidemiologia , Microbiologia de Alimentos , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Resistência Microbiana a Medicamentos , Antibacterianos/farmacologiaRESUMO
Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, with a mere 5-year survival of ~10%. This highlights the urgent need for innovative treatment options for PDAC patients. The nuclear factor κB (NF-κB) is a crucial transcription factor that is constitutively activated in PDAC. It mediates the transcription of oncogenic and inflammatory genes that facilitate multiple PDAC phenotypes. Thus, a better understanding of the mechanistic underpinnings of NF-κB activation holds great promise for PDAC diagnosis and effective therapeutics. Here, we report a novel finding that the p65 subunit of NF-κB is O-GlcNAcylated at serine 550 and 551 upon NF-κB activation. Importantly, the overexpression of either serine-to-alanine (S-A) single mutant (S550A or S551A) or double mutant (S550A/S551A) of p65 in PDAC cells impaired NF-κB nuclear translocation, p65 phosphorylation, and transcriptional activity, independent of IκBα degradation. Moreover, the p65 mutants downregulate a category of NF-κB-target genes, which play a role in perpetuating major cancer hallmarks. We further show that overexpression of the p65 mutants inhibited cellular proliferation, migration, and anchorage-independent growth of PDAC cells compared to WT-p65. Collectively, we discovered novel serine sites of p65 O-GlcNAcylation that drive NF-κB activation and PDAC phenotypes, thus opening new avenues by inhibiting the NF-κB O-GlcNAcylation enzyme, O-GlcNAc transferase (OGT), for PDAC treatment in the future.
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Background: The liver flukes of the Fasciola species and Dicrocoelium spp. are recognised as parasites of domestic and wild herbivores. Both species of F. hepatica and F. gigantica as well as D. dendriticum are distributed in Iran. The present study aimed to identify Fasciola spp. and Dicrocoelium spp. using mitochondrial Cox1 (cytochrome c oxidase I) gene by HRM method. Methods: Totally, thirty infected liver specimens were collected from the sheep (n:23) and cattle (n:7) at the abattoirs of Qazvin Province, northwest Iran in 2022. DNA extraction and PCR amplification of Cox1 gene were conducted by HRM technique. DnaSP v.5.0 was used for compression of diversity indices of ribosomal 28S rDNA and mitochondrial Cox1 markers of Dicrocoelium spp. The taxonomic status of Dicrocoelium spp. was performed by sequencing and phylogenetic analysis. Results: Overall, 26 and 4 isolates were identified as F. hepatica and F. gigantica, respectively. D. dendriticum was the sole infecting species of Dicrocoelium revealed by HRM analysis. Genomic analysis showed a moderate (28S rDNA genes: 0.600±0.215) to high (Cox1: 0.733±0.155) haplotype diversity for D. dendriticum. Conclusion: The parasite-dependent mitochondrial gene (Cox1) could identify a higher genetic diversity of D. dendriticum compared to nuclear 28S rDNA gene. HRM technique in the present study found to be a reliable technique for identification and genetic diversity of liver flukes but more comprehensive and in-depth studies in different parts of the country are needed.
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Background and Objectives: The lactobacilli are abundant in honey, helping protect against pathogens and providing antimicrobial properties. This study aimed to isolate lactobacillus species from different honey regions and evaluate their potential probiotic properties. Materials and Methods: Eighty-eight samples were collected from different regions, including the northern, central, and southern areas, and obtained through retail stores. All samples were independently examined for the presence of Lactobacillus using both culture and real-time PCR methods. Probiotic tests were performed on the isolated Lactobacillus strains, including hemolytic activity, bile, acid, and pepsin resistance. Additionally, the antibiotic resistance of the obtained strains was investigated using seven different antibiotics. Results: Thirteen Lactobacillus isolates were obtained from 7 (8.0%) honey samples. Of these, eight isolates were identified as L. plantarum (61.54%), four isolates as L. rhamnosus (30.77%), and one isolate as L. acidophilus (7.69%). All strains were devoid of hemolytic activity, and three isolates (23.07%) were found to be resistant to acid, while 2 (15.38%) showed resistance to bile and pepsin. All isolates were resistant to vancomycin (100%). Additionally, only one strain exhibited resistance to all tested antibiotics. Furthermore, the present study demonstrates a significant association (p-value<0.05) between the presence of Lactobacillus in various regions of Iran. Conclusion: Various factors, such as climatic conditions and geographical location, can influence honey's composition and microbial diversity. Identifying and isolating potential probiotic species in honey could significantly expand their use in the food and pharmaceutical industries, offering numerous health benefits and potential therapeutic applications.
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Market drugs, such as Food and Drug Administration (FDA) or European Medicines Agency (EMA)-approved drugs for specific indications provide opportunities for repurposing for newer therapeutics. This potentially saves resources invested in clinical trials that verify drug safety and tolerance in humans prior to alternative indication approval. Protein arginine methyltransferase 5 (PRMT5) overexpression has been linked to promoting the tumor phenotype in several cancers, including pancreatic ductal adenocarcinoma (PDAC), colorectal cancer (CRC), and breast cancer (BC), making PRMT5 an important target for cancer therapy. Previously, we showed that PRMT5-mediated methylation of the nuclear factor (NF)-κB, partially contributes to its constitutive activation observed in cancers. In this study, we utilized an AlphaLISA-based high-throughput screening method adapted in our lab, and identified one FDA-approved drug, Candesartan cilexetil (Can, used in hypertension treatment) and one EMA-approved drug, Cloperastine hydrochloride (Clo, used in cough treatment) that had significant PRMT5-inhibitory activity, and their anti-tumor properties were validated using cancer phenotypic assays in vitro. Furthermore, PRMT5 selective inhibition of methyltransferase activity was confirmed by reduction of both NF-κB methylation and its subsequent activation upon drug treatment. Using in silico prediction, we identified critical residues on PRMT5 targeted by these drugs that may interfere with its enzymatic activity. Finally, Clo and Can treatment have exhibited marked reduction in tumor growth in vivo. Overall, we provide basis for pursuing repurposing Clo and Can as anti-PRMT5 cancer therapies. Our study offers potential safe and fast repurposing of previously unknown PRMT5 inhibitors into clinical practice.
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Resistance to anticancer agents and apoptosis results in cancer relapse and is associated with cancer mortality. Substantial data have provided convincing evidence establishing that human cancers emerge from cancer stem cells (CSCs), which display self-renewal and are resistant to anticancer drugs, radiation, and apoptosis, and express enhanced epithelial to mesenchymal progression. CSCs represent a heterogeneous tumor cell population and lack specific cellular targets, which makes it a great challenge to target and eradicate them. Similarly, their close relationship with the tumor microenvironment creates greater complexity in developing novel treatment strategies targeting CSCs. Several mechanisms participate in the drug and apoptosis resistance phenotype in CSCs in various cancers. These include enhanced expression of ATP-binding cassette membrane transporters, activation of various cytoprotective and survival signaling pathways, dysregulation of stemness signaling pathways, aberrant DNA repair mechanisms, increased quiescence, autophagy, increased immune evasion, deficiency of mitochondrial-mediated apoptosis, upregulation of anti-apoptotic proteins including c-FLIP [cellular FLICE (FADD-like IL-1ß-converting enzyme)-inhibitory protein], Bcl-2 family members, inhibitors of apoptosis proteins, and PI3K/AKT signaling. Studying such mechanisms not only provides mechanistic insights into these cells that are unresponsive to drugs, but may lead to the development of targeted and effective therapeutics to eradicate CSCs. Several studies have identified promising strategies to target CSCs. These emerging strategies may help target CSC-associated drug resistance and metastasis in clinical settings. This article will review the CSCs drug and apoptosis resistance mechanisms and how to target CSCs.
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BACKGROUND: Determination of the prevalence of intestinal protozoan infection is a fundamental step to set up an effective control program to improve the health status of society and to establish efficient strategies. Intestinal pathogen and even non-pathogen protozoa consider as major causes of disease in patients with gastrointestinal problems. The objective of this study is to determine the prevalence of intestinal protozoan infection in patients with ulcerative colitis (UC) in Isfahan, Iran. METHODS: The descriptive cross-sectional study carried out from 2013 to 2018 in Isfahan, Iran. One thousand nine hundred and sixty-five samples of feces from patients with UC collected and each sample examined using direct wet mounting with normal saline and iodine and sedimentation tests such as formol-ethyl acetate concentration and trichrome-staining methods. RESULTS: From 655 patients, 185 (28.2%) infected with Giardia lamblia followed by Blastocystis hominis (27.3%), Endolimax nana (14.4%), Entamoeba coli (11.5%), Iodamoba butschlii (4.7%), Entamoeba histolytica (1.4%), and Chilomastix mesnili (0.6%). CONCLUSIONS: This study revealed a high prevalence of infection with at least one or six non-pathogenic and pathogenic intestinal protozoa in UC patients in the Isfahan region. Intestinal protozoa are a challenging public health problem wherever health care is limited in the area. The emergence of UC in the world results in the need to study etiologic factors. In order to obtain further information about the etiology of disease, we investigated the prevalence of intestinal protozoan infection in patients with UC in Isfahan, Iran.
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Cellular FLICE (FADD-like IL-1beta-converting enzyme)-inhibitory protein (c-FLIP) is a major resistance factor for the tumor necrosis factor-related apoptosis-inducing ligand TRAIL and in drug resistance in human malignancies. c-FLIP is an antagonist of caspases-8 and -10, which inhibits apoptosis and is expressed as long (c-FLIP(L)) and short (c-FLIP(S)) splice forms. c-FLIP is often overexpressed in various human cancers, including breast cancer. Several studies have shown that silencing c-FLIP by specific siRNAs sensitizes cancer cells to TRAIL and anticancer agents. However, systemic use of siRNA as a therapeutic agent is not practical at present. In order to reduce or inhibit c-FLIP expression, small molecules are needed to allow targeting c-FLIP without inhibiting caspases-8 and -10. We used a small molecule inhibitor of c-FLIP, 4-(4-chloro-2-methylphenoxy)-N-hydroxybutanamide (CMH), and show that CMH, but not its inactive analog, downregulated c-FLIP(L) and c-FLIP(S) mRNA and protein levels, caused poly(ADP-ribose) polymerase (PARP) degradation, reduced cell survival, and induced apoptosis in MCF-7 breast cancer cells. These results revealed that c-FLIP is a critical apoptosis regulator that can serve as a target for small molecule inhibitors that downregulate its expression and serve as effective targeted therapeutics against breast cancer cells.
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Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/antagonistas & inibidores , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Ácidos Hidroxâmicos/farmacologia , RNA Mensageiro/antagonistas & inibidores , Western Blotting , Neoplasias da Mama/metabolismo , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Ácidos Hidroxâmicos/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais CultivadasRESUMO
Human cancers emerge from cancer stem cells (CSCs), which are resistant to cancer chemotherapeutic agents, radiation, and cell death. Moreover, autophagy provides the cytoprotective effect which contributes to drug resistance in these cells. Furthermore, much evidence shows that CSCs cause tumor initiation, progression, metastasis, and cancer recurrence. Various signaling pathways including the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR), maternal embryonic leucine zipper kinase (MELK), NOTCH1, and Wnt/ß-catenin as well as the CSC markers maintain CSC properties. Several mechanisms including overexpression of ABC multidrug resistance transporters, a deficiency in mitochondrial-mediated apoptosis, upregulation of c-FLIP, overexpression of anti-apoptotic Bcl-2 family members and inhibitors of apoptosis proteins (IAPs), and PI3K/AKT signaling contribute to enhancing resistance to chemotherapeutic drugs and cell death induction in CSCs in various cancers. Studying such pathways may help provide detailed understanding of CSC mechanisms of resistance to chemotherapeutic agents and apoptosis and may lead to the development of effective therapeutics to eradicate CSCs.
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Metastasis, tumor progression, and chemoresistance are the major causes of death in patients with pancreatic ductal adenocarcinoma (PDAC). Tumor dissemination is associated with the activation of an epithelial-to-mesenchymal transition (EMT) process, a program by which epithelial cells lose their cell polarity and cell-to-cell adhesion, and acquire migratory and invasive abilities to become mesenchymal stem cells (MSC). These MSCs are multipotent stromal cells capable of differentiating into various cell types and trigger the phenotypic transition from an epithelial to a mesenchymal state. Therefore, EMT promotes migration and survival during cancer metastasis and confers stemness features to particular subsets of cells. Furthermore, a major problem limiting our ability to treat PDAC is the existence of rare populations of pancreatic cancer stem cells (PCSCs) or cancer-initiating cells in pancreatic tumors. PCSCs may represent sub-populations of tumor cells resistant to therapy which are most crucial for driving invasive tumor growth. These cells are capable of regenerating the cellular heterogeneity associated with the primary tumor when xenografted into mice. Therefore, the presence of PCSCs has prognostic relevance and influences the therapeutic response of tumors. PCSCs express markers of cancer stem cells (CSCs) including CD24, CD133, CD44, and epithelial specific antigen as well as the drug transporter ABCG2 grow as spheroids in a defined growth medium. A major difficulty in studying tumor cell dissemination and metastasis has been the identification of markers that distinguish metastatic cancer cells from cells that are normally circulating in the bloodstream or at sites where these cells metastasize. Evidence highlights a linkage between CSC and EMT. In this review, The current understanding of the PCSCs, signaling pathways regulating these cells, PDAC heterogeneity, EMT mechanism, and links between EMT and metastasis in PCSCs are summarised. This information may provide potential therapeutic strategies to prevent EMT and trigger CSC growth inhibition and cell death.
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BACKGROUND: Among the human parasitic diseases, malaria is the main cause of morbidity and mortality. To prevent the high mortality and tracking malaria elimination efforts, a prompt and sensitive diagnosis is essential. This study aimed to compare High-Resolution Melting (HRM) and microscopic methods to diagnose Plasmodium falciparum and P. vivax. METHODS: Eighty-one blood samples were collected from patients with clinical symptoms who were suspect to malaria in Chabahar district, southeastern Iran and also, from those who were referred to Malaria National Laboratory in the Tehran University of Medical Sciences, Tehran, Iran. Microscopic examination and HRM method were used to the diagnosis of Plasmodium parasites simultaneously. RESULTS: Microscopic results revealed 45 positive cases (12 P. falciparum and 33 P. vivax) out of 81 collected samples while according to HRM analysis results 11 and 33 samples were identified as P. falciparum and P. vivax, respectively. HRM analysis also revealed 1 mixed infection of P. falciparum and P. malariae. CONCLUSION: HRM analysis provides a promising mean for simultaneous detection and discrimination of the Plasmodium spp. especially in mixed infection cases.
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BACKGROUND: Toxoplasma gondii is an obligate intracellular protozoan with worldwide distribution. Diagnosis of toxoplasmosis is a very critical issue, especially in pregnant women and immunocompromised patients. The aim of this study was rapid detection of T. gondii DNA in peripheral blood samples (PBS) employing HRM technique and using RE gene. METHODS: Totally, 242 samples from pregnant women and human immunodeficiency virus (HIV) patients were collected from different hospitals and medical centers of Tehran during Oct 2017 to Dec 2018. High resolution melting analysis (HRM) using partial sequences of repetitive element (RE) gene was done and compared with ELISA test. RESULTS: Overall, 51 were positive for acute toxoplasmosis that among them, 12 and 20 reported as positive in pregnant women and HIV+ patients, respectively using HRM technique. Among 70 patients in chronic phase of disease, 10 and 3 samples were reported as positive for pregnant women and HIV+ patients respectively. From 121 negative control, 3 (4.62%) samples associated with HIV+ patients, showed positive real-time PCR and HRM analysis results. CONCLUSION: For the first time, HRM technique via employing RE gene was used for detection of T. gondii infection in PBS. This method is suitable, helpful and in parallel with serological methods for early diagnosis of acute as well as active form of toxoplasmosis in pregnant women and HIV+ patients. The use of techniques based on melt curve and through employing next-generation dyes for diagnosis of T. gondii would be accessible for patients in developing countries.
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BACKGROUND: Asymptomatic malaria, which usually exists in low parasitemia, acts as the Plasmodium species reservoirs contributing towards malaria transmission. This situation hinders malaria elimination programs in endemic areas, thus necessitating an active case detection with a high sensitive method and treatment of cases. This is why we used a High Resolution Melting (HRM) assay to monitor the trend of asymptomatic malaria in a malaria endemic area of Iran which is under elimination program. METHODS: The peripheral blood was sampled from 271 clinically approved non-febrile individuals from a malaria endemic zone of southeastern Iran for asymptomatic malaria prevalence detection by microscopy, Rapid Diagnostic Tests (RDTs) and HRM methods. The HRM assay was done based on the amplification of 18S SSU rRNA gene. RESULTS: The HRM assay revealed infections from three individuals out of 271 (1.1% asymptomatic malaria prevalence) from the participants, two Iranian natives with Plasmodium vivax infection and one Pakistani immigrant with P. falciparum infection. Neither microscopy nor RDTs detected Plasmodium spp infections from the 271 non-febrile individuals. The nucleotide sequencing analysis of the positive controls used in this study showed a close homology with the reference gene bank sequences of P. falciparum 3D7 (CPO16995.1) and P. vivax Sal-1(UO3079.1). CONCLUSION: This study revealed a low frequency of asymptomatic malaria trend within malaria endemic areas of southeastern Iran which are under intense elimination program and also the ability of HRM assay in detecting low Plasmodium spp parasitemia beyond the limits of microscopy and RDTs.
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BACKGROUND: We aimed at genotyping and evaluating the predominance of G. duodenalis assemblages isolated from patients referred to medical laboratories in Khorramabad, Iran from Nov 2015 to Sep 2016. Hence, the development of a cost-effective HRM approach to determine genotypes of G. duodenalis based on the triosephosphate isomerase (tpi) gene was examined and the genotyping results with and without diarrhea was compared. METHODS: Seventy G. duodenalis positive fecal samples were collected. A microscopic confirmation for the presence of Giardia spp. was performed, cysts of 70 Giardia spp. positive specimens were concentrated using sucrose flotation technique and sucrose solution PCR amplification was performed on 69 of 70 (98.5%) samples, and High Resolution Melting (HRM) analysis was performed using a software. RESULTS: The results showed two distinct genotypes (assemblages A and B) of G. duodenalis but infections with mixture of both assemblages were not detected. The genotypes of G. duodenalis showed that the sub assemblage AI, BIII and BIV were present in a proportion of 68.1%, 20.3% and 11.6% respectively in samples. Assemblage AI was significantly (P<0.05) more frequently found in patients with diarrhea. CONCLUSION: The sub-assemblage AI, BIII, and BIV are more zoonotic potential. According to the comparison of the results of this study with the results of previous studies in this area and around of it, as well as the way people live and keep pets. This pattern established in Khorramabad city. HRM can be an ideal technique to detect and genotyping of G. duodenalis in clinical samples.
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In this report, we reveal that etoposide inhibits the proliferation of SK-N-AS neuroblastoma cancer cells and promotes protein kinase Cdelta (PKCdelta)- and caspase-dependent apoptosis. Etoposide induces the caspase-3-dependent cleavage of PKCdelta to its active p40 fragment, and active PKCdelta triggers the processing of caspase-3 by a positive-feedback mechanism. Treatment of cells with the caspase-3-specific inhibitor N-benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethyl ketone or caspase-3-specific small interacting RNA (siRNA) prevented the etoposide-induced activation of caspase-8 and inhibited apoptosis. The silencing of the caspase-2 or caspase-8 genes using siRNAs did not affect the etoposide-induced processing of caspase-3, indicating that these caspases lie downstream of caspase-3 in this signaling pathway. Furthermore, the etoposide-induced processing of caspase-2 required the expression of caspase-8, and the etoposide-mediated processing of caspase-8 required the expression of caspase-2, indicating that these two caspases activate each other after etoposide treatment. We also observed that etoposide-mediated apoptosis was decreased by treating the cells with the caspase-6-specific inhibitor benzyloxycarbonyl-Val-Glu(OMe)-Ile-Asp-(OMe)-fluoromethyl ketone and that caspase-6 was activated by a caspase-8-dependent mechanism. Finally, we show that rottlerin blocks etoposide-induced apoptosis by inhibiting the PKCdelta-mediated activation of caspase-3 and by degrading caspase-2, which prevents caspase-8 activation. Our results add important insights into how etoposide mediates apoptotic signaling and how targeting these pathways may lead to the development of novel therapeutics for the treatment of neuroblastomas.