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1.
J Biol Chem ; 294(38): 14081-14095, 2019 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-31366730

RESUMEN

TP53 is the most frequently mutated tumor suppressor gene in many cancers, yet biochemical characterization of several of its reported mutations with probable biological significance have not been accomplished enough. Specifically, missense mutations in TP53 can contribute to tumorigenesis through gain-of-function of biochemical and biological properties that stimulate tumor growth. Here, we identified a relatively rare mutation leading to a proline to leucine substitution (P152L) in TP53 at the very end of its DNA-binding domain (DBD) in a sample from an Indian oral cancer patient. Although the P152Lp53 DBD alone bound to DNA, the full-length protein completely lacked binding ability at its cognate DNA motifs. Interestingly, P152Lp53 could efficiently tetramerize, and the mutation had only a limited impact on the structure and stability of full-length p53. Significantly, when we expressed this variant in a TP53-null cell line, it induced cell motility, proliferation, and invasion compared with a vector-only control. Also, enhanced tumorigenic potential was observed when P152Lp53-expressing cells were xenografted into nude mice. Investigating the effects of P152Lp53 expression on cellular pathways, we found that it is associated with up-regulation of several pathways, including cell-cell and cell-extracellular matrix signaling, epidermal growth factor receptor signaling, and Rho-GTPase signaling, commonly active in tumorigenesis and metastasis. Taken together, our findings provide a detailed account of the biochemical and cellular alterations associated with the cancer-associated P152Lp53 variant and establish it as a gain-of-function TP53 variant.


Asunto(s)
Carcinogénesis/genética , Proteína p53 Supresora de Tumor/genética , Animales , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Femenino , Mutación con Ganancia de Función , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Neoplasias de la Boca/genética , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Invasividad Neoplásica/genética , Polimorfismo de Nucleótido Simple , Transducción de Señal/genética , Activación Transcripcional , Proteína p53 Supresora de Tumor/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
2.
Mod Pathol ; 29(12): 1532-1540, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27562493

RESUMEN

Recurrent mutations in the myogenic transcription factor MYOD1 and PIK3CA were initially described in a subset of embryonal rhabdomyosarcomas. Recently, two independent studies demonstrated presence of MYODI (L122R) mutations as the basis to re-classify a spindle cell rhabdomyosarcoma, along with a sclerosing rhabdomyosarcoma, distinct from an embryonal rhabdomyosarcoma. We analyzed a much larger cohort of 49 primary rhabdomyosarcoma tumor samples of various subtypes, collected over a period of 9 years, for the presence of MYOD1 (L122R), PIK3CA (H1047), and PIK3CA (E542/E545) mutations, along with immunohistochemical analysis of desmin, myogenin, and MYOD1. Although activating PIK3CA mutations were absent across the sample set analyzed, we report 20% MYOD1 (L122R) mutation in rhabdomyosarcomas, found exclusively in 10 of 21 spindle cell and sclerosing rhabdomyosarcomas, occurring mostly in the head and neck region along with extremity sites (64%), than the paratesticular and intra-abdominal sites. Furthermore, while all 10 MYOD1 mutant spindle cell and sclerosing rhabdomyosarcoma samples showed diffuse and strong MYOD1 immunoexpression, 7 of 31 samples of rhabdomyosarcoma with wild-type MYOD1 were negative for MYOD1 expression. Clinically, a striking correlation was found between MYOD1 mutation and the clinical outcomes available for 15 of 21 cases: 5 of 7 patients with spindle cell and sclerosing rhabdomyosarcomas, harboring MYOD1 mutation, were alive-with-disease and 2 of 8 patients with spindle cell and sclerosing rhabdomyosarcomas, with mutant MYOD1, were free-of-disease. Taken together, we present the first report of MYOD1 (L122R) mutation in the largest cohort of 49 rhabdomyosarcomas reported so far, that are associated with a relatively aggressive clinical course. Moreover, consistent with the earlier two studies, this study further reinforces a relationship between spindle cell and the sclerosing rhabdomyosarcoma-now recognized as a single subtype, distinct from an embryonal rhabdomyosarcoma.


Asunto(s)
Biomarcadores de Tumor/genética , Proteína MioD/genética , Rabdomiosarcoma/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Rabdomiosarcoma/patología , Adulto Joven
3.
BMC Genomics ; 16: 936, 2015 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-26572163

RESUMEN

BACKGROUND: Several statistical tools have been developed to identify genes mutated at rates significantly higher than background, indicative of positive selection, involving large sample cohort studies. However, studies involving smaller sample sizes are inherently restrictive due to their limited statistical power to identify low frequency genetic variations. RESULTS: We performed an integrated characterization of copy number, mutation and expression analyses of four head and neck cancer cell lines - NT8e, OT9, AW13516 and AW8507 - by applying a filtering strategy to prioritize for genes affected by two or more alterations within or across the cell lines. Besides identifying TP53, PTEN, HRAS and MET as major altered HNSCC hallmark genes, this analysis uncovered 34 novel candidate genes altered. Of these, we find a heterozygous truncating mutation in Nuclear receptor binding protein, NRBP1 pseudokinase gene, identical to as reported in other cancers, is oncogenic when ectopically expressed in NIH-3 T3 cells. Knockdown of NRBP1 in an oral carcinoma cell line bearing NRBP1 mutation inhibit transformation and survival of the cells. CONCLUSIONS: In overall, we present the first comprehensive genomic characterization of four head and neck cancer cell lines established from Indian patients. We also demonstrate the ability of integrated analysis to uncover biologically important genetic variation in studies involving fewer or rare clinical specimens.


Asunto(s)
Carcinoma de Células Escamosas/genética , Genómica/métodos , Neoplasias de Cabeza y Cuello/genética , Línea Celular Tumoral , Supervivencia Celular , ADN de Neoplasias , Dosificación de Gen , Humanos , Cariotipo , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Receptores Citoplasmáticos y Nucleares/genética , Análisis de Secuencia de ADN , Carcinoma de Células Escamosas de Cabeza y Cuello , Transcriptoma , Proteínas de Transporte Vesicular/genética
4.
NPJ Precis Oncol ; 8(1): 63, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438481

RESUMEN

Head and neck cancer is a major cause of morbidity and mortality worldwide. The identification of genetic alterations in head and neck cancer may improve diagnosis and treatment outcomes. In this study, we report the identification and functional characterization of UBE3C-LRP5 translocation in head and neck cancer. Our whole transcriptome sequencing and RT-PCR analysis of 151 head and neck cancer tumor samples identified the LRP5-UBE3C and UBE3C-LRP5 fusion transcripts in 5.3% of patients of Indian origin (n = 151), and UBE3C-LRP5 fusion transcripts in 1.2% of TCGA-HNSC patients (n = 502). Further, whole genome sequencing identified the breakpoint of UBE3C-LRP5 translocation. We demonstrate that UBE3C-LRP5 fusion is activating in vitro and in vivo, and promotes the proliferation, migration, and invasion of head and neck cancer cells. In contrast, depletion of UBE3C-LRP5 fusion suppresses the clonogenic, migratory, and invasive potential of the cells. The UBE3C-LRP5 fusion activates the Wnt/ß-catenin signaling by promoting nuclear accumulation of ß-catenin, leading to upregulation of Wnt/ß-catenin target genes, MYC, CCND1, TCF4, and LEF1. Consistently, treatment with the FDA-approved drug, pyrvinium pamoate, significantly reduced the transforming ability of cells expressing the fusion protein and improved survival in mice bearing tumors of fusion-overexpressing cells. Interestingly, fusion-expressing cells upon knockdown of CTNNB1, or LEF1 show reduced proliferation, clonogenic abilities, and reduced sensitivity to pyrvinium pamoate. Overall, our study suggests that the UBE3C-LRP5 fusion is a promising therapeutic target for head and neck cancer and that pyrvinium pamoate may be a potential drug candidate for treating head and neck cancer harboring this translocation.

5.
Anticancer Agents Med Chem ; 23(13): 1499-1505, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37070442

RESUMEN

Nature is the chief source of various remedies which are used to cure various diseases. Boswellic acid (BA) is a secondary metabolite from the pentacyclic terpenoid compound groups that are derived from the plant genus Boswellia. The oleo gum resins of these plants are primarily composed of polysaccharides, with the remaining amounts of resin (30-60%) and essential oils (5-10%) soluble in organic solvents. BA and its analogs are also reported to exhibit various in vivo and biological responses for example anti-inflammatory, anti-tumor, free radical scavenging activity, etc. Among all analogs, 11-keto-ß-boswellic acid (KBA) and 3-O-acetyl-11-keto-ß-boswellic acid (AKBA) has been demonstrated to be the most effective at reducing cytokine production and inhibiting the inflammatory responsecausing enzymes. In this review, we summarized the computational ADME prediction via the SwissADME computational tool and the structure-activity relationship of the Boswellic acid scaffold for the aspect of anticancer and antiinflammatory potency. In addition to these research findings which are associated with the therapy of acute inflammation and some cancers, the potential of boswellic acids against other disorders was also discussed.


Asunto(s)
Boswellia , Triterpenos , Humanos , Antiinflamatorios/farmacología , Relación Estructura-Actividad , Extractos Vegetales , Triterpenos/farmacología , Triterpenos/metabolismo
6.
Curr Diabetes Rev ; 2023 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-37691189

RESUMEN

Diabetes is a chronic metabolic disease affecting millions worldwide. It is characterized by a lack of insulin production or impaired insulin function, leading to elevated blood glucose levels. Conventional treatment methods for diabetes management typically include lifestyle changes and medications. However, alternative therapies have gained attention in recent years, including traditional medicine containing bioactive compounds, supplements like vitamin D and Omega-3 fatty acids, aromatherapy, and homeopathy. Diabetic complications are common in patients with uncontrolled diabetes and can lead to serious health problems, including diabetic retinopathy, impaired wound healing, kidney disease, nerve damage, and cardiovascular disease. Alternative remedies, such as traditional medicine containing bioactive compounds, supplements, and aromatherapy, have been studied for their potential benefits in managing these complications. Traditional medicines like bitter melon, cinnamon, and fenugreek have been shown to have anti-diabetic effects due to their bioactive compounds. Similarly, supplements like vitamin D and Omega-3 fatty acids have been found to improve glycemic control in patients with diabetes. Aromatherapy, which involves the use of essential oils, has also been explored for its potential benefits in diabetes management. Homeopathy, which uses highly diluted substances to stimulate the body's natural healing abilities, has been used to treat diabetes-related symptoms like neuropathy and wounds. Personalized care is essential in natural diabetes management because each person's body and health needs are unique. A holistic approach that addresses the individual's physical, emotional, and spiritual well-being is essential. As research in this field continues to expand, a more comprehensive understanding of diabetes management will lead to improved outcomes for those living with this condition.

7.
Commun Biol ; 6(1): 57, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36650344

RESUMEN

Occult lymph-node metastasis is a crucial predictor of tongue cancer mortality, with an unmet need to understand the underlying mechanism. Our immunohistochemical and real-time PCR analysis of 208 tongue tumors show overexpression of Matrix Metalloproteinase, MMP10, in 86% of node-positive tongue tumors (n = 79; p < 0.00001). Additionally, global profiling for non-coding RNAs associated with node-positive tumors reveals that of the 11 significantly de-regulated miRNAs, miR-944 negatively regulates MMP10 by targeting its 3'-UTR. We demonstrate that proliferation, migration, and invasion of tongue cancer cells are suppressed by MMP10 knockdown or miR-944 overexpression. Further, we show that depletion of MMP10 prevents nodal metastases using an orthotopic tongue cancer mice model. In contrast, overexpression of MMP10 leads to opposite effects upregulating epithelial-mesenchymal-transition, mediated by a tyrosine kinase gene, AXL, to promote nodal and distant metastasis in vivo. Strikingly, AXL expression is essential and sufficient to mediate the functional consequence of MMP10 overexpression. Consistent with our findings, TCGA-HNSC data suggests overexpression of MMP10 or AXL positively correlates with poor survival of the patients. In conclusion, our results establish that the miR-944/MMP10/AXL- axis underlies lymph node metastases with potential therapeutic intervention and prediction of nodal metastases in tongue cancer patients.


Asunto(s)
Tirosina Quinasa del Receptor Axl , Metaloproteinasa 10 de la Matriz , MicroARNs , Neoplasias de la Lengua , Animales , Ratones , Metástasis Linfática , Metaloproteinasa 10 de la Matriz/genética , MicroARNs/genética , Neoplasias de la Lengua/genética , Neoplasias de la Lengua/patología , Tirosina Quinasa del Receptor Axl/genética
8.
Exp Hematol ; 111: 50-65, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35429619

RESUMEN

The molecular events responsible for decitabine responses in myelodysplastic syndrome and acute myeloid leukemia patients are poorly understood. Decitabine has a short serum half-life and limited stability in tissue culture. Therefore, theoretical pharmacologic differences may exist between patient molecular changes in vitro and the consequences of in vivo treatment. To systematically identify the global genomic and transcriptomic alterations induced by decitabine in vivo, we evaluated primary bone marrow samples that were collected during patient treatment and applied whole-genome bisulfite sequencing, RNA-sequencing, and single-cell RNA sequencing. Decitabine induced global, reversible hypomethylation after 10 days of therapy in all patients, which was associated with induction of interferon-induced pathways, the expression of endogenous retroviral elements, and inhibition of erythroid-related transcripts, recapitulating many effects seen previously in in vitro studies. However, at relapse after decitabine treatment, interferon-induced transcripts remained elevated relative to day 0, but erythroid-related transcripts now were more highly expressed than at day 0. Clinical responses were not correlated with epigenetic or transcriptional signatures, although sample size and interpatient variance restricted the statistical power required for capturing smaller effects. Collectively, these data define global hypomethylation by decitabine and find that erythroid-related pathways may be relevant because they are inhibited by therapy and reverse at relapse.


Asunto(s)
Decitabina , Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Decitabina/uso terapéutico , Humanos , Interferones , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicos/tratamiento farmacológico , Síndromes Mielodisplásicos/genética , Recurrencia
9.
Swiss Med Wkly ; 150: w20195, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-32083704

RESUMEN

With the emerging advances made in genomics and functional genomics approaches, there is a critical and growing unmet need to integrate plural datasets in order to identify driver genes in cancer. An integrative approach, with the convergence of multiple types of genetic evidence, can limit false positives through a posterior filtering strategy and reduce the need for multiple hypothesis testing to identify true cancer vulnerabilities. We performed a pooled shRNA screen against 906 human genes in the oral cancer cell line AW13516 in triplicate. The genes that were depleted in the screen were integrated with copy number alteration and gene expression data and ranked based on ROAST analysis, using an integrative scoring system, DepRanker, to compute a Rank Impact Score (RIS) for each gene. The RIS-based ranking of candidate driver genes was used to identify the putative oncogenes AURKB and TK1 as essential for oral cancer cell proliferation. We validated the findings, showing that shRNA mediated genetic knockdown of TK1 or pharmacological inhibition of AURKB by AZD-1152 HQPA in AW13516 cells could significantly impede their proliferation. Next we analysed alterations in AURKB and TK1 genes in head and neck cancer and their association with prognosis using data on 528 patients obtained from TCGA. Patients harbouring alterations in AURKB and TK1 genes were associated with poor survival. To summarise, we present DepRanker as a simple yet robust package with no third-party dependencies for the identification of potential driver genes from a pooled shRNA functional genomic screen by integrating results from RNAi screens with gene expression and copy number data. Using DepRanker, we identify AURKB and TK1 as potential therapeutic targets in oral cancer. DepRanker is in the public domain and available for download at http://www.actrec.gov.in/pi-webpages/AmitDutt/DepRanker/DepRanker.html.


Asunto(s)
Aurora Quinasa B/genética , Tecnología de Genética Dirigida/métodos , Neoplasias de Cabeza y Cuello/genética , ARN Interferente Pequeño/genética , Timidina Quinasa/genética , Línea Celular , Genómica/métodos , Humanos , Oncogenes , Programas Informáticos , Sobrevida , Neoplasias de la Lengua/genética
10.
Oral Oncol ; 73: 56-64, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28939077

RESUMEN

OBJECTIVES: Nodal metastases status among early stage tongue squamous cell cancer patients plays a decisive role in the choice of treatment, wherein about 70% patients can be spared from surgery with an accurate prediction of negative pathological lymph node status. This underscores an unmet need for prognostic biomarkers to stratify the patients who are likely to develop metastases. MATERIALS AND METHODS: We performed high throughput sequencing of fifty four samples derived from HPV negative early stage tongue cancer patients habitual of chewing betel nuts, areca nuts, lime or tobacco using whole exome (n=47) and transcriptome (n=17) sequencing that were analyzed using in-house computational tools. Additionally, gene expression meta-analyses were carried out for 253 tongue cancer samples. The candidate genes were validated using qPCR and immuno-histochemical analysis in an extended set of 50 early primary tongue cancer samples. RESULTS AND CONCLUSION: Somatic analysis revealed a classical tobacco mutational signature C:G>A:T transversion in 53% patients that were mutated in TP53, NOTCH1, CDKN2A, HRAS, USP6, PIK3CA, CASP8, FAT1, APC, and JAK1. Similarly, significant gains at genomic locus 11q13.3 (CCND1, FGF19, ORAOV1, FADD), 5p15.33 (SHANK2, MMP16, TERT), and 8q24.3 (BOP1); and, losses at 5q22.2 (APC), 6q25.3 (GTF2H2) and 5q13.2 (SMN1) were observed in these samples. Furthermore, an integrated gene-expression analysis of 253 tongue tumors suggested an upregulation of metastases-related pathways and over-expression of MMP10 in 48% tumors that may be crucial to predict nodal metastases in early tongue cancer patients. In overall, we present the first descriptive portrait of somatic alterations underlying the genome of tobacco/nut chewing HPV-negative early tongue cancer, and identify MMP10 asa potential prognostic biomarker to stratify those likely to develop metastases.


Asunto(s)
Areca , Metaloproteinasa 10 de la Matriz/genética , Metástasis de la Neoplasia , Tabaco sin Humo , Neoplasias de la Lengua/genética , Adulto , Anciano , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Papillomaviridae/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa , Neoplasias de la Lengua/etiología , Neoplasias de la Lengua/patología , Neoplasias de la Lengua/virología , Secuenciación del Exoma
11.
Cell Death Discov ; 3: 17015, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28580170

RESUMEN

Bystander cells of the tumor microenvironment show evidence of DNA damage and inflammation that can lead to their oncogenic transformation. Mediator(s) of cell-cell communication that brings about these pro-oncogenic pathologies has not been identified. We show here that cell-free chromatin (cfCh) released from dying cancer cells are the key mediators that trigger both DNA damage and inflammation in the surrounding healthy cells. When dying human cancer cells were cultured along with NIH3T3 mouse fibroblast cells, numerous cfCh emerged from them and rapidly entered into nuclei of bystander NIH3T3 cells to integrate into their genomes. This led to activation of H2AX and inflammatory cytokines NFκB, IL-6, TNFα and IFNγ. Genomic integration of cfCh triggered global deregulation of transcription and upregulation of pathways related to phagocytosis, DNA damage and inflammation. None of these activities were observed when living cancer cells were co-cultivated with NIH3T3 cells. However, upon intravenous injection into mice, both dead and live cells were found to be active. Living cancer cells are known to undergo extensive cell death when injected intravenously, and we observed that cfCh emerging from both types of cells integrated into genomes of cells of distant organs and induced DNA damage and inflammation. γH2AX and NFκB were frequently co-expressed in the same cells suggesting that DNA damage and inflammation are closely linked pathologies. As concurrent DNA damage and inflammation is a potent stimulus for oncogenic transformation, our results suggest that cfCh from dying cancer cells can transform cells of the microenvironment both locally and in distant organs providing a novel mechanism of tumor invasion and metastasis. The afore-described pro-oncogenic pathologies could be abrogated by concurrent treatment with chromatin neutralizing/degrading agents suggesting therapeutic possibilities.

12.
Artículo en Inglés | MEDLINE | ID: mdl-27402678

RESUMEN

Cancer is predominantly a somatic disease. A mutant allele present in a cancer cell genome is considered somatic when it's absent in the paired normal genome along with public SNP databases. The current build of dbSNP, the most comprehensive public SNP database, however inadequately represents several non-European Caucasian populations, posing a limitation in cancer genomic analyses of data from these populations. We present the T: ata M: emorial C: entre-SNP D: ata B: ase (TMC-SNPdb), as the first open source, flexible, upgradable, and freely available SNP database (accessible through dbSNP build 149 and ANNOVAR)-representing 114 309 unique germline variants-generated from whole exome data of 62 normal samples derived from cancer patients of Indian origin. The TMC-SNPdb is presented with a companion subtraction tool that can be executed with command line option or using an easy-to-use graphical user interface with the ability to deplete additional Indian population specific SNPs over and above dbSNP and 1000 Genomes databases. Using an institutional generated whole exome data set of 132 samples of Indian origin, we demonstrate that TMC-SNPdb could deplete 42, 33 and 28% false positive somatic events post dbSNP depletion in Indian origin tongue, gallbladder, and cervical cancer samples, respectively. Beyond cancer somatic analyses, we anticipate utility of the TMC-SNPdb in several Mendelian germline diseases. In addition to dbSNP build 149 and ANNOVAR, the TMC-SNPdb along with the subtraction tool is available for download in the public domain at the following:Database URL: http://www.actrec.gov.in/pi-webpages/AmitDutt/TMCSNP/TMCSNPdp.html.


Asunto(s)
Pueblo Asiatico/genética , Bases de Datos de Ácidos Nucleicos , Genoma Humano , Mutación de Línea Germinal , Neoplasias/genética , Polimorfismo de Nucleótido Simple , Femenino , Humanos , India , Masculino
13.
Oncotarget ; 7(31): 50437-50449, 2016 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-27391340

RESUMEN

BACKGROUND: Notch pathway plays a complex role depending on cellular contexts: promotes stem cell maintenance or induces terminal differentiation in potential cancer-initiating cells; acts as an oncogene in lymphocytes and mammary tissue or plays a growth-suppressive role in leukemia, liver, skin, and head and neck cancer. Here, we present a novel clinical and functional significance of NOTCH1 alterations in early stage tongue squamous cell carcinoma (TSCC). PATIENTS AND METHODS: We analyzed the Notch signaling pathway in 68 early stage TSCC primary tumor samples by whole exome and transcriptome sequencing, real-time PCR based copy number, expression, immuno-histochemical, followed by cell based biochemical and functional assays. RESULTS: We show, unlike TCGA HNSCC data set, NOTCH1 harbors significantly lower frequency of inactivating mutations (4%); is somatically amplified; and, overexpressed in 31% and 37% of early stage TSCC patients, respectively. HNSCC cell lines over expressing NOTCH1, when plated in the absence of attachment, are enriched in stem cell markers and form spheroids. Furthermore, we show that inhibition of NOTCH activation by gamma secretase inhibitor or shRNA mediated knockdown of NOTCH1 inhibits spheroid forming capacity, transformation, survival and migration of the HNSCC cells suggesting an oncogenic role of NOTCH1 in TSCC. Clinically, Notch pathway activation is higher in tumors of non-smokers compared to smokers (50% Vs 18%, respectively, P=0.026) and is also associated with greater nodal positivity compared to its non-activation (93% Vs 64%, respectively, P=0.029). CONCLUSION: We anticipate that these results could form the basis for therapeutic targeting of NOTCH1 in tongue cancer.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Células Madre Neoplásicas/citología , Receptor Notch1/metabolismo , Neoplasias de la Lengua/metabolismo , Adulto , Anciano , Carcinoma de Células Escamosas/genética , Diferenciación Celular , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Supervivencia Celular , Exoma , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Mutación , Células Madre Neoplásicas/patología , Receptor Notch1/genética , Transducción de Señal/genética , Fumar/efectos adversos , Esferoides Celulares/metabolismo , Neoplasias de la Lengua/genética , Transcriptoma , Adulto Joven
14.
J Biosci ; 40(1): 91-111, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25740145

RESUMEN

Whether nucleic acids that circulate in blood have any patho-physiological functions in the host have not been explored.We report here that far from being inert molecules, circulating nucleic acids have significant biological activities of their own that are deleterious to healthy cells of the body. Fragmented DNA and chromatin (DNAfs and Cfs) isolated from blood of cancer patients and healthy volunteers are readily taken up by a variety of cells in culture to be localized in their nuclei within a few minutes. The intra-nuclear DNAfs and Cfs associate themselves with host cell chromosomes to evoke a cellular DNA-damage-repair-response (DDR) followed by their incorporation into the host cell genomes. Whole genome sequencing detected the presence of tens of thousands of human sequence reads in the recipient mouse cells. Genomic incorporation of DNAfs and Cfs leads to dsDNA breaks and activation of apoptotic pathways in the treated cells. When injected intravenously into Balb/C mice, DNAfs and Cfs undergo genomic integration into cells of their vital organs resulting in activation of DDR and apoptotic proteins in the recipient cells. Cfs have significantly greater activity than DNAfs with respect to all parameters examined, while both DNAfs and Cfs isolated from cancer patients are more active than those from normal volunteers. All the above pathological actions of DNAfs and Cfs described above can be abrogated by concurrent treatment with DNase I and/or anti-histone antibody complexed nanoparticles both in vitro and in vivo. Taken together, our results suggest that circulating DNAfs and Cfs are physiological, continuously arising, endogenous DNA damaging agents with implications to ageing and a multitude of human pathologies including initiation of cancer.


Asunto(s)
Cromatina/genética , Daño del ADN/genética , Reparación del ADN/genética , ADN/genética , Ácidos Nucleicos/sangre , Células 3T3 , Animales , Apoptosis/genética , Secuencia de Bases , Caspasa 3/metabolismo , Línea Celular Tumoral , Desoxirribonucleasa I/farmacología , Células HeLa , Histonas/metabolismo , Humanos , Ratones , Ratones Endogámicos BALB C , Neoplasias/sangre , Neoplasias/genética , Ácidos Nucleicos/genética , Análisis de Secuencia de ADN
15.
PLoS One ; 8(10): e76164, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24124538

RESUMEN

BACKGROUND: During the past decade, the incidence of EGFR mutation has been shown to vary across different ethnicities. It occurs at the rate of 10-15% in North Americans and Europeans, 19% in African-Americans, 20-30% in various East Asian series including Chinese, Koreans, and Japanese. Frequency of EGFR mutations in India however remains sparsely explored. METHODOLOGY/PRINCIPAL FINDINGS: We report 23% incidence of Epidermal growth factor receptor (EGFR) mutations in 907 Non small cell lung cancer (NSCLC) patients of Indian ethnicity, in contrast to 10-15% known in Caucasians and 27-62% among East Asians. In this study, EGFR mutations were found to be more common in never-smokers 29.4% as compared to smokers 15.3%. Consistent with other populations, mutation rates among adenocarcinoma-males were predominantly lower than females with 32% incidence. However unlike Caucasians, EGFR mutation rate among adenocarcinoma-never-smoker females were comparable to males suggesting lack of gender bias among never smokers likely to benefit from EGFR targeted therapy. CONCLUSIONS/SIGNIFICANCE: This study has an overall implication for establishing relevance for routine EGFR mutation diagnostics for NSCLC patients in clinics and emphasizes effectiveness for adoption of EGFR inhibitors as the first line treatment among Indian population. The intermediate frequency of EGFR mutation among Indian population compared to Caucasians and East Asians is reminiscent of an ancestral admixture of genetic influence from Middle Easterners, Central Asians, and Europeans on modern- Indian population that may confer differential susceptibility to somatic mutations in EGFR.


Asunto(s)
Adenocarcinoma/genética , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Adenocarcinoma del Pulmón , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Población Blanca
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