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1.
Front Microbiol ; 14: 1193380, 2023.
Article in English | MEDLINE | ID: mdl-37700866

ABSTRACT

Mycobacterium abscessus subsp. abscessus is a rapidly growing facultative intracellular pathogen that usually infects human lung and skin epithelium. Recently, we and another group have shown that it also has the potential to colonize human gastric epithelium, but its significance with respect to gastric diseases remains unclear. Although Helicobacter pylori still remains the only definite gastric pathogen, recent studies have shown that M. abscessus subsp. abscessus also has the potential to colonize human gastric epithelium. M. abscessus subsp. abscessus is known to exhibit multidrug resistance and clarithromycin has been used as the drug of choice. We aimed to determine the clarithromycin resistance profile of 117 (74 rough and 43 smooth) gastric M. abscessus subsp. abscessus strains and to detect the point mutations in rrl and erm (41) genes conferring the resistance. Our data showed 79.48% (19 smooth and 74 rough) of M. abscessus subsp. abscessus strains were resistant to clarithromycin (MIC90 ≤ 512 µg/mL), while 20.51% (24 smooth) were susceptible (MIC90 ≤ 8 µg/mL). Nucleotide sequence analysis of the rrl gene with reference strains of M. abscessus subsp. abscessus did not show any mutation that is relevant to the clarithromycin resistance. However, analysis of erm (41) gene showed that M. abscessus subsp. abscessus strains, which were susceptible to clarithromycin had C, C, G, and C at their nucleotide positions 28, 159, 238, and 330, respectively, while the resistant strains showed T, T, A, and A at the same positions. Based on antibiogram and sequence analysis data we recommend further studies involving genomic analysis to identify the other genes involved in high clarithromycin resistance in gastric M. abscessus subsp. abscessus along with the mechanisms involved.

2.
Cells ; 11(23)2022 Nov 28.
Article in English | MEDLINE | ID: mdl-36497066

ABSTRACT

Many human cancers, including breast cancer, are polygenic and involve the co-dysregulation of multiple regulatory molecules and pathways. Though the overexpression of genes and amplified chromosomal regions have been closely linked in breast cancer, the notion of the co-upregulation of genes at a single locus remains poorly described. Here, we describe the co-overexpression of 34 continuously organized protein-coding genes with diverse functions at 8q.24.3(143437655-144326919) in breast and other cancer types, the CanCord34 genes. In total, 10 out of 34 genes have not been reported to be overexpressed in breast cancer. Interestingly, the overexpression of CanCord34 genes is not necessarily associated with genomic amplification and is independent of hormonal or HER2 status in breast cancer. CanCord34 genes exhibit diverse known and predicted functions, including enzymatic activities, cell viability, multipotency, cancer stem cells, and secretory activities, including extracellular vesicles. The co-overexpression of 33 of the CanCord34 genes in a multivariant analysis was correlated with poor survival among patients with breast cancer. The analysis of the genome-wide RNAi functional screening, cell dependency fitness, and breast cancer stem cell databases indicated that three diverse overexpressed CanCord34 genes, including a component of spliceosome PUF60, a component of exosome complex EXOSC4, and a ribosomal biogenesis factor BOP1, shared roles in cell viability, cell fitness, and stem cell phenotypes. In addition, 17 of the CanCord34 genes were found in the microvesicles (MVs) secreted from the mesenchymal stem cells that were primed with MDA-MB-231 breast cancer cells. Since these MVs were important in the chemoresistance and dedifferentiation of breast cancer cells into cancer stem cells, these findings highlight the significance of the CanCord34 genes in cellular communications. In brief, the persistent co-overexpression of CanCord34 genes with diverse functions can lead to the dysregulation of complementary functions in breast cancer. In brief, the present study provides new insights into the polygenic nature of breast cancer and opens new research avenues for basic, preclinical, and therapeutic studies in human cancer.


Subject(s)
Breast Neoplasms , Humans , Female , Breast Neoplasms/metabolism , Cell Line, Tumor , RNA Interference , Cell Survival , Genomics
3.
BMC Infect Dis ; 22(1): 676, 2022 Aug 06.
Article in English | MEDLINE | ID: mdl-35933382

ABSTRACT

BACKGROUND: The incidence of high-risk human papillomavirus (hrHPV)-driven head and neck squamous cell carcinoma, in particular oropharyngeal cancers (OPC), is increasing in high-resource countries. Patients with HPV-induced cancer respond better to treatment and consequently have lower case-fatality rates than patients with HPV-unrelated OPC. These considerations highlight the importance of reliable and accurate markers to diagnose truly HPV-induced OPC. METHODS: The accuracy of three possible test strategies, i.e. (a) hrHPV DNA PCR (DNA), (b) p16(INK4a) immunohistochemistry (IHC) (p16), and (c) the combination of both tests (considering joint DNA and p16 positivity as positivity criterion), was analysed in tissue samples from 99 Belgian OPC patients enrolled in the HPV-AHEAD study. Presence of HPV E6*I mRNA (mRNA) was considered as the reference, indicating HPV etiology. RESULTS: Ninety-nine OPC patients were included, for which the positivity rates were 36.4%, 34.0% and 28.9% for DNA, p16 and mRNA, respectively. Ninety-five OPC patients had valid test results for all three tests (DNA, p16 and mRNA). Using mRNA status as the reference, DNA testing showed 100% (28/28) sensitivity, and 92.5% (62/67) specificity for the detection of HPV-driven cancer. p16 was 96.4% (27/28) sensitive and equally specific (92.5%; 62/67). The sensitivity and specificity of combined p16 + DNA testing was 96.4% (27/28) and 97.0% (65/67), respectively. In this series, p16 alone and combined p16 + DNA missed 1 in 28 HPV driven cancers, but p16 alone misclassified 5 in 67 non-HPV driven as positive, whereas combined testing would misclassify only 2 in 67. CONCLUSIONS: Single hrHPV DNA PCR and p16(INK4a) IHC are highly sensitive but less specific than using combined testing to diagnose HPV-driven OPC patients. Disease prognostication can be encouraged based on this combined test result.


Subject(s)
Carcinoma, Squamous Cell , Oropharyngeal Neoplasms , Papillomavirus Infections , Carcinoma, Squamous Cell/diagnosis , Cyclin-Dependent Kinase Inhibitor p16/genetics , DNA, Viral/analysis , DNA, Viral/genetics , Humans , Immunohistochemistry , Oropharyngeal Neoplasms/diagnosis , Oropharyngeal Neoplasms/pathology , Papillomaviridae/genetics , Papillomavirus Infections/complications , Papillomavirus Infections/diagnosis , Polymerase Chain Reaction , RNA, Messenger/analysis
4.
Cells ; 11(15)2022 07 25.
Article in English | MEDLINE | ID: mdl-35892586

ABSTRACT

Overexpression and hyperactivation of the serine/threonine protein kinase B (AKT) pathway is one of the most common cellular events in breast cancer progression. However, the nature of AKT1-specific genome-wide transcriptomic alterations in breast cancer cells and breast cancer remains unknown to this point. Here, we delineate the impact of selective AKT1 knock down using gene-specific siRNAs or inhibiting the AKT activity with a pan-AKT inhibitor VIII on the nature of transcriptomic changes in breast cancer cells using the genome-wide RNA-sequencing analysis. We found that changes in the cellular levels of AKT1 lead to changes in the levels of a set of differentially expressed genes and, in turn, imply resulting AKT1 cellular functions. In addition to an expected positive relationship between the status of AKT1 and co-expressed cellular genes, our study unexpectedly discovered an inherent role of AKT1 in inhibiting the expression of a subset of genes in both unstimulated and growth factor stimulated breast cancer cells. We found that depletion of AKT1 leads to upregulation of a subset of genes-many of which are also found to be downregulated in breast tumors with elevated high AKT1 as well as upregulated in breast tumors with no detectable AKT expression. Representative experimental validation studies in two breast cancer cell lines showed a reasonable concurrence between the expression data from the RNA-sequencing and qRT-PCR or data from ex vivo inhibition of AKT1 activity in cancer patient-derived cells. In brief, findings presented here provide a resource for further understanding of AKT1-dependent modulation of gene expression in breast cancer cells and broaden the scope and significance of AKT1 targets and their functions.


Subject(s)
Breast Neoplasms , Proto-Oncogene Proteins c-akt , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Female , Humans , Proto-Oncogene Proteins c-akt/genetics , RNA , Transcriptome
5.
Cells ; 11(12)2022 06 15.
Article in English | MEDLINE | ID: mdl-35741056

ABSTRACT

The prognosis of breast cancer (BC) in young women (BCYW) aged ≤40 years tends to be poorer than that in older patients due to aggressive phenotypes, late diagnosis, distinct biologic, and poorly understood genomic features of BCYW. Considering the estimated predisposition of only approximately 15% of the BC population to BC-promoting genes, the underlying reasons for an increased occurrence of BCYW, at large, cannot be completely explained based on general risk factors for BC. This underscores the need for the development of next-generation of tissue- and body fluid-based prognostic and predictive biomarkers for BCYW. Here, we identified the genes associated with BCYW with a particular focus on the age, intrinsic BC subtypes, matched normal or normal breast tissues, and BC laterality. In young women with BC, we observed dysregulation of age-associated cancer-relevant gene sets in both cancer and normal breast tissues, sub-sets of which substantially affected the overall survival (OS) or relapse-free survival (RFS) of patients with BC and exhibited statically significant correlations with several gene modules associated with cellular processes such as the stroma, immune responses, mitotic progression, early response, and steroid responses. For example, high expression of COL1A2, COL5A2, COL5A1, NPY1R, and KIAA1644 mRNAs in the BC and normal breast tissues from young women correlated with a substantial reduction in the OS and RFS of BC patients with increased levels of these exemplified genes. Many of the genes upregulated in BCYW were overexpressed or underexpressed in normal breast tissues, which might provide clues regarding the potential involvement of such genes in the development of BC later in life. Many of BCYW-associated gene products were also found in the extracellular microvesicles/exosomes secreted from breast and other cancer cell-types as well as in body fluids such as urine, saliva, breast milk, and plasma, raising the possibility of using such approaches in the development of non-invasive, predictive and prognostic biomarkers. In conclusion, the findings of this study delineated the pathogenomics of BCYW, providing clues for future exploration of the potential predictive and prognostic importance of candidate BCYW molecules and research strategies as well as a rationale to undertake a prospective clinical study to examine some of testable hypotheses presented here. In addition, the results presented here provide a framework to bring out the importance of geographical disparities, to overcome the current bottlenecks in BCYW, and to make the next quantum leap for sporadic BCYW research and treatment.


Subject(s)
Breast Neoplasms , Aged , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Female , Gene Regulatory Networks , Humans , Neoplasm Recurrence, Local/genetics , Prospective Studies , RNA, Messenger
6.
Antib Ther ; 5(2): 100-110, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35437514

ABSTRACT

Quantitative determination of neutralizing antibodies against Severe Acute Respiratory Syndrome Corona Virus-2 (SARS-CoV-2) is paramount in immunodiagnostics, vaccine efficacy testing, and immune response profiling among the vaccinated population. Cost-effective, rapid, easy-to-perform assays are essential to support the vaccine development process and immunosurveillance studies. We describe a bead-based screening assay for S1-neutralization using recombinant fluorescent proteins of hACE2 and SARS-CoV2-S1, immobilized on solid beads employing nanobodies/metal-affinity tags. Nanobody-mediated capture of SARS-CoV-2-Spike (S1) on agarose beads served as the trap for soluble recombinant ACE2-GFPSpark, inhibited by neutralizing antibody. The first approach demonstrates single-color fluorescent imaging of ACE2-GFPSpark binding to His-tagged S1-Receptor Binding Domain (RBD-His) immobilized beads. The second approach is dual-color imaging of soluble ACE2-GFPSpark to S1-Orange Fluorescent Protein (S1-OFPSpark) beads. Both methods showed a good correlation with the gold standard pseudovirion assay and can be adapted to any fluorescent platforms for screening.

7.
Cells ; 10(10)2021 10 05.
Article in English | MEDLINE | ID: mdl-34685645

ABSTRACT

To broaden the understanding of the epigenomic and chromatin regulation of cervical cancer, we examined the status and significance of a set of epigenomic and chromatin modifiers in cervical cancer using computational biology. We observed that 61 of 917 epigenomic and/or chromatin regulators are differentially upregulated in human cancer, including 25 upregulated in invasive squamous cell carcinomas and 29 in cervical intraepithelial neoplasia 3 (CIN3), of which 14 are upregulated in cervical intraepithelial neoplasia 2 (CIN2). Interestingly, 57 of such regulators are uniquely upregulated in cervical cancer, but not ovarian and endometrial cancers. The observed overexpression of 57 regulators was found to have a prognostic significance in cervical cancer. The collective overexpression of these regulators, as well as its subsets belonging to specific histone modifications and corresponding top ten positively co-overexpressed genes, correlated with reduced survival of patients with high expressions of the tested overexpressed regulators compared to cases with low expressions. Using cell-dependency datasets from human cervical cancer cells, we found that 20 out of 57 epigenomic and chromatin regulators studied here appeared to be essential genes, as the depletion of these genes was accompanied by the loss in cellular viability. In brief, the results presented here provide further insights into the role of epigenomic and chromatin regulators in the oncobiology of cervical cancer and broaden the list of new potential molecules of therapeutic importance.


Subject(s)
Chromatin/metabolism , Epigenomics , Uterine Cervical Neoplasms/genetics , Female , Gene Expression Regulation, Neoplastic , Humans , Prognosis , Survival Analysis , Transcriptome/genetics , Up-Regulation/genetics
8.
Cancer Epidemiol ; 72: 101925, 2021 06.
Article in English | MEDLINE | ID: mdl-33839457

ABSTRACT

BACKGROUND: The main risk factors for head and neck cancer (HNC) are tobacco and alcohol use. However, an important fraction of oropharyngeal cancer (OPC) is caused by human papillomaviruses (HPV), a subgroup with increasing incidence in several western countries. METHODS: As part of the HPV-AHEAD study, we assessed the role of HPV infection in 772 archived tissue specimens of Belgian HNC patients: 455 laryngeal (LC), 106 oral cavity (OCC), 99 OPC, 76 hypopharyngeal (HC), and 36 unspecified parts of the head and neck. All specimens were tested for HPV DNA (21 genotypes); whereof all HPV DNA-positives, all HPV DNA-negative OPCs and a random subset of HPV DNA-negatives of the other HNC-sites were tested for the presence of type-specific HPV RNA and p16INK4a over-expression. RESULTS: The highest HPV DNA prevalence was observed in OPC (36.4 %), and was significantly lower (p < 0.001) in the other HNCs (OCC:7.5 %, LC:6.6 %). HPV16 was the most common HPV-genotype in all HNCs. Approximately 83.0 % of the HPV DNA-positive OPCs tested HPV RNA or p16-positive, compared to about 37.5 % and 44.0 % in OCC and LC, respectively. Estimation of the attributable fraction of an HPV infection in HNC was very similar for HPV RNA or p16 in addition to DNA-positivity; with 30 % for OPC, and 3 % for OCC and LC. CONCLUSION: Our study confirms the heterogeneity of HPV DNA prevalence across anatomical sites in HNC, with a predominance of HPV16 in all sites. The estimated proportion of HPV-driven HNC in Belgium, during the period 1980-2014, was 10 times higher in OPC compared to OCC and LC.


Subject(s)
Alphapapillomavirus/genetics , DNA, Viral/genetics , Head and Neck Neoplasms/virology , Papillomavirus Infections/virology , RNA, Messenger/isolation & purification , Adult , Aged , Aged, 80 and over , Belgium , Cyclin-Dependent Kinase Inhibitor p16 , Female , Genotype , Head and Neck Neoplasms/therapy , Humans , Ki-67 Antigen , Male , Middle Aged , Oncogene Proteins, Viral/genetics , Staining and Labeling
9.
Sci Rep ; 11(1): 8570, 2021 04 21.
Article in English | MEDLINE | ID: mdl-33883570

ABSTRACT

Although a defective vitamin D endocrine system has been widely suspected to be associated in SARS-CoV-2 pathobiology, the status of the vitamin D endocrine system and vitamin D-modulated genes in lung cells of patients infected with SARS-CoV-2 remains unknown. To understand the significance of the vitamin D endocrine system in SARS-CoV-2 pathobiology, computational approaches were applied to transcriptomic datasets from bronchoalveolar lavage fluid (BALF) cells of such patients or healthy individuals. Levels of vitamin D receptor, retinoid X receptor, and CYP27A1 in BALF cells of patients infected with SARS-CoV-2 were found to be reduced. Additionally, 107 differentially expressed, predominantly downregulated genes, as potentially modulated by vitamin D endocrine system, were identified in transcriptomic datasets from patient's cells. Further analysis of differentially expressed genes provided eight novel genes with a conserved motif with vitamin D-responsive elements, implying the role of both direct and indirect mechanisms of gene expression by the dysregulated vitamin D endocrine system in SARS-CoV-2-infected cells. Protein-protein interaction network of differentially expressed vitamin D-modulated genes were enriched in the immune system, NF-κB/cytokine signaling, and cell cycle regulation as top predicted pathways that might be affected in the cells of such patients. In brief, the results presented here povide computational evidence to implicate a dysregulated vitamin D endocrine system in the pathobiology of SARS-CoV-2 infection.


Subject(s)
Bronchoalveolar Lavage Fluid/chemistry , COVID-19/genetics , Computational Biology/methods , Gene Expression Profiling/methods , Gene Regulatory Networks , Vitamin D/metabolism , A549 Cells , COVID-19/metabolism , Case-Control Studies , Cell Line , Cholestanetriol 26-Monooxygenase/genetics , Databases, Genetic , Down-Regulation , High-Throughput Nucleotide Sequencing , Humans , Protein Interaction Maps , Receptors, Calcitriol/genetics , Retinoid X Receptors/genetics
10.
Cells ; 10(2)2021 02 18.
Article in English | MEDLINE | ID: mdl-33670680

ABSTRACT

To define the growing significance of cellular targets and/or effectors of cancer drugs, we examined the fitness dependency of cellular targets and effectors of cancer drug targets across human cancer cells from 19 cancer types. We observed that the deletion of 35 out of 47 cellular effectors and/or targets of oncology drugs did not result in the expected loss of cell fitness in appropriate cancer types for which drugs targeting or utilizing these molecules for their actions were approved. Additionally, our analysis recognized 43 cellular molecules as fitness genes in several cancer types in which these drugs were not approved, and thus, providing clues for repurposing certain approved oncology drugs in such cancer types. For example, we found a widespread upregulation and fitness dependency of several components of the mevalonate and purine biosynthesis pathways (currently targeted by bisphosphonates, statins, and pemetrexed in certain cancers) and an association between the overexpression of these molecules and reduction in the overall survival duration of patients with breast and other hard-to-treat cancers, for which such drugs are not approved. In brief, the present analysis raised cautions about off-target and undesirable effects of certain oncology drugs in a subset of cancers where the intended cellular effectors of drug might not be good fitness genes and that this study offers a potential rationale for repurposing certain approved oncology drugs for targeted therapeutics in additional cancer types.


Subject(s)
Molecular Targeted Therapy/methods , Neoplasms/therapy , Oncogenes/genetics , Humans , Medical Oncology , Neoplasms/mortality , Phenotype , Survival Analysis
11.
Microbiol Resour Announc ; 9(12)2020 Mar 19.
Article in English | MEDLINE | ID: mdl-32193233

ABSTRACT

Here, we report the complete sequence of four influenza A(H1N1) virus samples isolated from cases that occurred during the 2017 epidemic season in Kerala in South India. Sequence analysis showed mutations that differentiate this strain from the reference strain A/California/07/2009 virus.

14.
Vaccine ; 36(32 Pt A): 4783-4791, 2018 08 06.
Article in English | MEDLINE | ID: mdl-29551226

ABSTRACT

BACKGROUND: Human papillomavirus (HPV) vaccination is a major strategy for preventing cervical and other ano-genital cancers. Worldwide HPV vaccination introduction and coverage will be facilitated if a single dose of vaccine is as effective as two or three doses or demonstrates significant protective effect compared to 'no vaccination'. METHODS: In a multi-centre cluster randomized trial of two vs three doses of quadrivalent HPV vaccination (Gardasil™) in India, suspension of the vaccination due to events unrelated to the study led to per protocol and partial vaccination of unmarried 10-18 year old girls leading to four study groups, two by design and two by default. They were followed up for the primary outcomes of immunogenicity in terms of L1 genotype-specific binding antibody titres, neutralising antibody titres, and antibody avidity for the vaccine-targeted HPV types and HPV infections. Analysis was per actual number of vaccine doses received. This study is registered with ISRCTN, number ISRCTN98283094; and with ClinicalTrials.gov, number NCT00923702. FINDINGS: Of the 17,729 vaccinated girls, 4348 (25%) received three doses on days 1, 60, 180 or later, 4979 (28%) received two doses on days 1 and 180 or later, 3452 (19%) received two doses on days 1 and 60, and 4950 (28%) received one dose. One dose recipients demonstrated a robust and sustained immune response against HPV 16 and 18, albeit inferior to that of 3- or 2-doses and the antibody levels were stable over a 4 year period. The frequencies of cumulative incident and persistent HPV 16 and 18 infections up to 7 years of follow-up were similar and uniformly low in all the vaccinated study groups; the frequency of HPV 16 and 18 infections were significantly higher in unvaccinated age-matched control women than among vaccine recipients. The frequency of vaccine non-targeted HPV types was similar in the vaccinated groups but higher in the unvaccinated control women. CONCLUSION: Our results indicate that a single dose of quadrivalent HPV vaccine is immunogenic and provides lasting protection against HPV 16 and 18 infections similar to the three- and two-dose vaccine schedules, although the study suffer from some limitations. Data on long term protection beyond 7 years against HPV infection and cervical precancerous lesions are needed before policy guidelines regarding a single dose can be formulated and implemented. Significant and long-lasting protective effect of a single dose can be a strong argument to introduce one dose of the HPV vaccine in many low income countries where the current standard of care for cervical cancer prevention is 'no intervention'.


Subject(s)
Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18/administration & dosage , Human papillomavirus 16/immunology , Human papillomavirus 18/immunology , Papillomavirus Infections/prevention & control , Uterine Cervical Neoplasms/prevention & control , Adolescent , Antibodies, Neutralizing/immunology , Antibody Affinity/immunology , Child , Female , Follow-Up Studies , Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18/therapeutic use , Humans , Immunization Schedule , Immunogenicity, Vaccine/immunology , India/epidemiology , Papillomavirus Infections/epidemiology , Time Factors , Uterine Cervical Neoplasms/epidemiology , Young Adult
15.
Mol Cancer ; 17(1): 76, 2018 03 26.
Article in English | MEDLINE | ID: mdl-29580241

ABSTRACT

DNA damage-specific histone chaperone Aprataxin PNK-like factor (APLF) regulates mesenchymal-to-epithelial transition (MET) during cellular reprogramming. We investigated the role of APLF in epithelial-to-mesenchymal transition (EMT) linked to breast cancer invasiveness and metastasis. Here, we show that a significant manifestation of APLF is present in tumor sections of patients with invasive ductal carcinoma when compared to their normal adjacent tissues. APLF was significantly induced in triple negative breast cancer (TNBC) cells, MDAMB-231, in comparison to invasive MCF7 or normal MCF10A breast cells and supported by studies on invasive breast carcinoma in The Cancer Genome Atlas (TCGA). Functionally, APLF downregulation inhibited proliferative capacity, altered cell cycle behavior, induced apoptosis and impaired DNA repair ability of MDAMB-231 cells. Reduction in APLF level impeded invasive, migratory, tumorigenic and metastatic potential of TNBC cells with loss in expression of genes associated with EMT while upregulation of MET-specific gene E-cadherin (CDH1). So, here we provided novel evidence for enrichment of APLF in breast tumors, which could regulate metastasis-associated EMT in invasive breast cancer. We anticipate that APLF could be exploited as a biomarker for breast tumors and additionally could be targeted in sensitizing cancer cells towards DNA damaging agents.


Subject(s)
Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/pathology , DNA-(Apurinic or Apyrimidinic Site) Lyase/metabolism , Poly-ADP-Ribose Binding Proteins/metabolism , Up-Regulation , Animals , Biomarkers, Tumor/metabolism , Breast Neoplasms/metabolism , Carcinoma, Ductal, Breast/metabolism , Cell Line, Tumor , Cell Movement , Cell Proliferation , Epithelial-Mesenchymal Transition , Female , Gene Expression Regulation, Neoplastic , Humans , Mice , Neoplasm Transplantation , Tissue Array Analysis , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology
16.
Sci Rep ; 8(1): 2810, 2018 02 12.
Article in English | MEDLINE | ID: mdl-29434241

ABSTRACT

In cervical cancer, the association between HPV infection and dysregulation of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway (PI3K/AKT/mTOR pathway) places mTOR as an attractive therapeutic target. The failure of current treatment modalities in advanced stages of this cancer and drawbacks of already available mTOR inhibitors demand for novel drug candidates. In the present study we identified the presence of a mTOR inhibitor in an active fraction of the ethyl acetate extract of Streptomyces sp OA293. The metabolites(s) in the active fraction completely inhibited mTORC1 and thereby suppressed activation of both of its downstream targets, 4E-BP1 and P70S6k, in cervical cancer cells. In addition, it also stalled Akt activation via inhibition of mTORC2. The mechanism of mTOR inhibition detailed in our study overcomes significant drawbacks of well known mTOR inhibitors such as rapamycin and rapalogs. The active fraction induced autophagy and Bax mediated apoptosis suggesting that mTOR inhibition resulted in programmed cell death of cancer cells. The molecular weight determination of the components in active fraction confirmed the absence of any previously known natural mTOR inhibitor. This is the first report of complete mTOR complex inhibition by a product derived from microbial source.


Subject(s)
Biological Products/pharmacology , Streptomyces/chemistry , TOR Serine-Threonine Kinases/antagonists & inhibitors , Uterine Cervical Neoplasms/metabolism , bcl-2-Associated X Protein/metabolism , Apoptosis/drug effects , Apoptosis/physiology , Autophagy/drug effects , Autophagy/physiology , Cell Line, Tumor , Cell Proliferation/drug effects , Female , HEK293 Cells , Humans , Mechanistic Target of Rapamycin Complex 1/metabolism , Phosphatidylinositol 3-Kinase/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , Sirolimus/pharmacology , Streptomyces/metabolism , TOR Serine-Threonine Kinases/metabolism
17.
Oncol Res ; 26(1): 17-26, 2018 Jan 19.
Article in English | MEDLINE | ID: mdl-28276309

ABSTRACT

This study is an integrated analysis of the transcriptome profile microRNA (miRNA) and its experimentally validated mRNA targets differentially expressed in the tumorigenic stem-like fraction of oral squamous cell carcinoma (OSCC). We had previously reported the coexistence of multiple drug-resistant tumorigenic fractions, termed side population (SP1, SP2, and MP2), and a nontumorigenic fraction, termed main population (MP1), in oral cancer. These fractions displayed a self-renewal, regenerative potential and expressed known stemness-related cell surface markers despite functional differences. Flow cytometrically sorted pure fractions of SP1 and MP1 cells were subjected to differential expression analysis of both mRNAs and miRNAs. A significant upregulation of genes associated with inflammation, cell survival, cell proliferation, drug transporters, and antiapoptotic pathways, in addition to enhanced transcriptome reprogramming mediated by DNA-histone binding proteins and pattern recognition receptor-mediated signaling, was found to play a crucial role in the transformation of the nontumorigenic MP1 fraction to the tumorigenic SP1 fraction. We also identified several differentially expressed miRNAs that specifically target genes distinctive of tumorigenic SP1 fraction. miRNA-mediated downregulation of stemness-associated markers CD44 and CD147 and upregulation of CD151 may also account for the emergence and persistence of multiple tumorigenic stem cell fractions with varying degrees of malignancy. The phenotypic switch of cancer cells to stem-like OSCC cells mediated by transcriptomal regulation is effectual in addressing biological tumor heterogeneity and subsequent therapeutic resistance leading to a minimal residual disease (MRD) condition in oral cancer. A detailed study of the interplay of miRNAs, mRNA, and the cellular phases involved in the gradual transition of nontumorigenic cancer cells to tumorigenic stem-like cells in solid tumors would enable detection and development of a treatment regimen that targets and successfully eliminates multiple, drug-resistant fractions of cancer cells.


Subject(s)
Carcinoma, Squamous Cell/pathology , Cell Transformation, Neoplastic/genetics , Head and Neck Neoplasms/pathology , Mouth Neoplasms/pathology , Neoplastic Stem Cells/pathology , Side-Population Cells/pathology , Carcinoma, Squamous Cell/genetics , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/genetics , Head and Neck Neoplasms/genetics , Humans , MicroRNAs/analysis , MicroRNAs/genetics , Mouth Neoplasms/genetics , RNA, Messenger/analysis , RNA, Messenger/genetics , Squamous Cell Carcinoma of Head and Neck , Transcriptome
18.
Int J Cancer ; 141(1): 143-151, 2017 07 01.
Article in English | MEDLINE | ID: mdl-28369859

ABSTRACT

Mucosal high-risk (HR) human papillomaviruses (HPV) cause a subset of head and neck cancers (HNC). The HPV-attributable fraction of HNC varies substantially between countries. Although HNC has a very high incidence in the Indian subcontinent, information on the contribution of HPV infection is limited. Here, we evaluated the HPV-attributable fraction in HNC (N = 364) collected in a central region of India. HNC from three different anatomical subsites were included, namely, oral cavity (n = 252), oropharynx (n = 53) and hypopharynx/larynx (n = 59). In this retrospective study, HPV-driven HNC were defined by presence of both viral DNA and RNA. Overexpression of p16INK4a was also evaluated. HR-HPV DNA was detected in 13.7% of the cases; however, only 2.7% were positive for both HPV DNA and RNA. The highest percentage of HPV DNA/RNA double positivity was found in oropharynx (9.4%), followed by larynx (1.7%) and oral cavity (1.6%) (p = 0.02). More than half of HPV DNA/RNA-positive cases were p16INK4a -negative, while a considerable number of HPV RNA-negative cases were p16INK4a -positive (17.9%). HPV16 was the major type associated with HNC (60.0%), although cases positive for HPV18, 35 and 56 were also detected. Our data indicate that the proportion and types of mucosal HR-HPV associated with HNC in this central Indian region differ from those in other (developed) parts of the world. This may be explained by differences in smoking and/or sexual behaviour compared with North America and northern Europe. Moreover, we show that p16INK4a staining appeared not to be a good surrogate marker of HPV transformation in the Indian HNC cases.


Subject(s)
Head and Neck Neoplasms/epidemiology , Head and Neck Neoplasms/virology , Papillomaviridae/pathogenicity , Papillomavirus Infections/epidemiology , Papillomavirus Infections/virology , Adult , Aged , Cyclin-Dependent Kinase Inhibitor p16/genetics , Female , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/pathology , Humans , India/epidemiology , Male , Middle Aged , Papillomaviridae/classification , Papillomaviridae/genetics , Papillomavirus Infections/genetics , Papillomavirus Infections/pathology
19.
Immunity ; 46(4): 587-595, 2017 04 18.
Article in English | MEDLINE | ID: mdl-28423338

ABSTRACT

Although vaccines confer protection against influenza A viruses, antiviral treatment becomes the first line of defense during pandemics because there is insufficient time to produce vaccines. Current antiviral drugs are susceptible to drug resistance, and developing new antivirals is essential. We studied host defense peptides from the skin of the South Indian frog and demonstrated that one of these, which we named "urumin," is virucidal for H1 hemagglutinin-bearing human influenza A viruses. This peptide specifically targeted the conserved stalk region of H1 hemagglutinin and was effective against drug-resistant H1 influenza viruses. Using electron microscopy, we showed that this peptide physically destroyed influenza virions. It also protected naive mice from lethal influenza infection. Urumin represents a unique class of anti-influenza virucide that specifically targets the hemagglutinin stalk region, similar to targeting of antibodies induced by universal influenza vaccines. Urumin therefore has the potential to contribute to first-line anti-viral treatments during influenza outbreaks.


Subject(s)
Amphibian Proteins/pharmacology , Influenza A virus/drug effects , Influenza, Human/prevention & control , Orthomyxoviridae Infections/prevention & control , Peptides/pharmacology , Amino Acid Sequence , Amphibian Proteins/immunology , Animals , Antiviral Agents/immunology , Antiviral Agents/pharmacology , Dogs , Dose-Response Relationship, Drug , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Hemagglutinin Glycoproteins, Influenza Virus/metabolism , Host-Pathogen Interactions/drug effects , Host-Pathogen Interactions/immunology , Humans , Influenza A virus/immunology , Influenza A virus/metabolism , Influenza, Human/immunology , Influenza, Human/virology , Madin Darby Canine Kidney Cells , Mice, Inbred BALB C , Orthomyxoviridae Infections/immunology , Orthomyxoviridae Infections/virology , Peptides/immunology , Ranidae/metabolism , Survival Analysis , Treatment Outcome , Virion/drug effects , Virion/immunology , Virion/metabolism
20.
J Cell Sci ; 129(24): 4576-4591, 2016 12 15.
Article in English | MEDLINE | ID: mdl-27875275

ABSTRACT

Induction of pluripotency in differentiated cells through the exogenous expression of the transcription factors Oct4, Sox2, Klf4 and cellular Myc involves reprogramming at the epigenetic level. Histones and their metabolism governed by histone chaperones constitute an important regulator of epigenetic control. We hypothesized that histone chaperones facilitate or inhibit the course of reprogramming. For the first time, we report here that the downregulation of histone chaperone Aprataxin PNK-like factor (APLF) promotes reprogramming by augmenting the expression of E-cadherin (Cdh1), which is implicated in the mesenchymal-to-epithelial transition (MET) involved in the generation of induced pluripotent stem cells (iPSCs) from mouse embryonic fibroblasts (MEFs). Downregulation of APLF in MEFs expedites the loss of the repressive MacroH2A.1 (encoded by H2afy) histone variant from the Cdh1 promoter and enhances the incorporation of active histone H3me2K4 marks at the promoters of the pluripotency genes Nanog and Klf4, thereby accelerating the process of cellular reprogramming and increasing the efficiency of iPSC generation. We demonstrate a new histone chaperone (APLF)-MET-histone modification cohort that functions in the induction of pluripotency in fibroblasts. This regulatory axis might provide new mechanistic insights into perspectives of epigenetic regulation involved in cancer metastasis.


Subject(s)
Carrier Proteins/metabolism , Fibroblasts/metabolism , Histone Chaperones/metabolism , Induced Pluripotent Stem Cells/metabolism , Animals , Cadherins/genetics , Cadherins/metabolism , Cell Cycle Checkpoints/genetics , Cell Differentiation/genetics , Cellular Reprogramming/genetics , Colony-Forming Units Assay , DNA Repair/genetics , DNA-(Apurinic or Apyrimidinic Site) Lyase , Down-Regulation/genetics , Embryo, Mammalian/cytology , Epithelial Cells/cytology , Female , Fibroblasts/cytology , Gene Knockdown Techniques , HEK293 Cells , Histones/metabolism , Humans , Induced Pluripotent Stem Cells/cytology , Kruppel-Like Factor 4 , Lysine/metabolism , Male , Mesoderm/cytology , Methylation , Mice , Mice, Inbred C57BL , Poly-ADP-Ribose Binding Proteins , Promoter Regions, Genetic/genetics , Up-Regulation/genetics
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