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3.
J Biomed Opt ; 26(8)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34402266

RESUMO

SIGNIFICANCE: Screening and early detection of oral potentially malignant lesions (OPMLs) are of great significance in reducing the mortality rates associated with head and neck malignancies. Intra-oral multispectral optical imaging of tissues in conjunction with cloud-based machine learning (CBML) can be used to detect oral precancers at the point-of-care (POC) and guide the clinician to the most malignant site for biopsy. AIM: Develop a bimodal multispectral imaging system (BMIS) combining tissue autofluorescence and diffuse reflectance (DR) for mapping changes in oxygenated hemoglobin (HbO2) absorption in the oral mucosa, quantifying tissue abnormalities, and guiding biopsies. APPROACH: The hand-held widefield BMIS consisting of LEDs emitting at 405, 545, 575, and 610 nm, 5MPx monochrome camera, and proprietary Windows-based software was developed for image capture, processing, and analytics. The DR image ratio (R610/R545) was compared with pathologic classification to develop a CBML algorithm for real-time assessment of tissue status at the POC. RESULTS: Sensitivity of 97.5% and specificity of 92.5% were achieved for discrimination of OPML from patient normal in 40 sites, whereas 82% sensitivity and 96.6% specificity were obtained for discrimination of abnormal (OPML + SCC) in 89 sites. Site-specific algorithms derived for buccal mucosa (27 sites) showed improved sensitivity and specificity of 96.3% for discrimination of OPML from normal. CONCLUSIONS: Assessment of oral cancer risk is possible by mapping of HbO2 absorption in tissues, and the BMIS system developed appears to be suitable for biopsy guidance and early detection of oral cancers.


Assuntos
Computação em Nuvem , Detecção Precoce de Câncer , Algoritmos , Biópsia , Humanos , Aprendizado de Máquina , Sensibilidade e Especificidade
4.
Sci Rep ; 11(1): 7787, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33833339

RESUMO

Aberrant activation of the PI3K/AKT/mTOR pathway is attributed to the pathogenesis of oral squamous cell carcinoma (OSCC). In recent years, increasing evidence suggests the involvement of microRNAs (miRNAs) in oral carcinogenesis by acting as tumor suppressors or oncogenes. TSC1, as a component of the above pathway, regulates several cellular functions such as cell proliferation, apoptosis, migration and invasion. Downregulation of TSC1 is reported in oral as well as several other cancers and is associated with an unfavourable clinical outcome in patients. Here we show that oncogenic miR-130a binds to the 3'UTR of TSC1 and represses its expression. MiR-130a-mediated repression of TSC1 increases cell proliferation, anchorage independent growth and invasion of OSCC cells, which is dependent on the presence of the 3'UTR in TSC1. We observe an inverse correlation between the expression levels of miR-130a and TSC1 in OSCC samples, suggesting that their interaction is physiologically relevant. Delivery of antagomiR-130a to OSCC cells results in a significant decrease in xenograft size. Taken together, the findings of the study indicate that miR-130a-mediated TSC1 downregulation is not only a novel mechanism in OSCC, but also the restoration of TSC1 levels by antagomiR-130a may be a potential therapeutic strategy for the treatment of OSCC.


Assuntos
Neoplasias de Cabeça e Pescoço/metabolismo , MicroRNAs/fisiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
5.
iScience ; 23(6): 101229, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32554190

RESUMO

Ex vivo human tumor models have emerged as promising, yet complex tools to study cancer immunotherapy response dynamics. Here, we present a strategy that integrates empirical data from an ex vivo human system with computational models to interpret the response dynamics of a clinically prescribed PD-1 inhibitor, nivolumab, in head and neck squamous cell carcinoma (HNSCC) biopsies (N = 50). Using biological assays, we show that drug-induced variance stratifies samples by T helper type 1 (Th1)-related pathways. We then built a systems biology network and mathematical framework of local and global sensitivity analyses to simulate and estimate antitumor phenotypes, which implicate a dynamic role for the induction of Th1-related cytokines and T cell proliferation patterns. Together, we describe a multi-disciplinary strategy to analyze and interpret the response dynamics of PD-1 blockade using heterogeneous ex vivo data and in silico simulations, which could provide researchers a powerful toolset to interrogate immune checkpoint inhibitors.

7.
Oncotarget ; 10(64): 6855-6869, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31839879

RESUMO

The human transcriptional coactivator PC4 has numerous roles to play in the cell. Other than its transcriptional coactivation function, it facilitates chromatin organization, DNA damage repair, viral DNA replication, etc. Although it was found to be an essential protein in vivo, the importance of this multifunctional protein in the regulation of different cellular pathways has not been investigated in details, particularly in oncogenesis. In this study, PC4 downregulation was observed in a significant proportion of mammary tissues obtained from Breast cancer patient samples as well as in a subset of highly invasive and metastatic Breast cancer patient-derived cell lines. We have identified a miRNA, miR-29a which potentially reduce the expression of PC4 both in RNA and protein level. This miR-29a was found to be indeed overexpressed in a substantial number of Breast cancer patient samples and cell lines as well, suggesting one of the key mechanisms of PC4 downregulation. Stable Knockdown of PC4 in MCF7 cells induced its migratory as well as invasive properties. Furthermore, in an orthotopic breast cancer mice model system; we have shown that reduced expression of PC4 enhances the tumorigenic potential substantially. Absence of PC4 led to the upregulation of several genes involved in Epithelial to Mesenchymal Transition (EMT), indicating the possible mechanism of uniform tumour progression in the orthotropic mice. Collectively these data establish the role of PC4 in tumour suppression.

8.
Sci Signal ; 12(595)2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31431543

RESUMO

Metastable phenotypic state transitions in cancer cells can lead to the development of transient adaptive resistance or tolerance to chemotherapy. Here, we report that the acquisition of a phenotype marked by increased abundance of CD44 (CD44Hi) by breast cancer cells as a tolerance response to routinely used cytotoxic drugs, such as taxanes, activated a metabolic switch that conferred tolerance against unrelated standard-of-care chemotherapeutic agents, such as anthracyclines. We characterized the sequence of molecular events that connected the induced CD44Hi phenotype to increased activity of both the glycolytic and oxidative pathways and glucose flux through the pentose phosphate pathway (PPP). When given in a specific order, a combination of taxanes, anthracyclines, and inhibitors of glucose-6-phosphate dehydrogenase (G6PD), an enzyme involved in glucose metabolism, improved survival in mouse models of breast cancer. The same sequence of the three-drug combination reduced the viability of patient breast tumor samples in an explant system. Our findings highlight a convergence between phenotypic and metabolic state transitions that confers a survival advantage to cancer cells against clinically used drug combinations. Pharmacologically targeting this convergence could overcome cross-drug tolerance and could emerge as a new paradigm in the treatment of cancer.


Assuntos
Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , Inibidores Enzimáticos/farmacologia , Glucose/metabolismo , Glucosefosfato Desidrogenase/antagonistas & inibidores , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias , Via de Pentose Fosfato/efeitos dos fármacos , Glucosefosfato Desidrogenase/metabolismo , Humanos , Células MCF-7 , Metástase Neoplásica , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia
9.
Oncotarget ; 10(38): 3709-3724, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31217904

RESUMO

Coactivator associated arginine methyltransferase 1 (CARM1) has been functionally implicated in maintenance of pluripotency, cellular differentiation and tumorigenesis; where it plays regulatory roles by virtue of its ability to coactivate transcription as well as to modulate protein function as an arginine methyltransferase. Previous studies establish an oncogenic function of CARM1 in the context of colorectal and breast cancer, which correlate to its overexpressed condition. However, the mechanism behind its deregulated expression in the context of cancer has not been addressed before. In the present study we uncover an oncogenic function of CARM1 in the context of oral cancer, where it was found to be overexpressed. We also identify YY1 to be a positive regulator of CARM1 gene promoter, where silencing of YY1 in oral cancer cell line could lead to reduction in expression of CARM1. In this context, YY1 showed concomitant overexpression in oral cancer patient samples compared to adjacent normal tissue. Cell line based experiments as well as xenograft study revealed pro-neoplastic functions of YY1 in oral cancer. Transcriptomics analysis as well as qRT-PCR validation clearly indicated pro-proliferative, pro-angiogenic and pro-metastatic role of YY1 in oral cancer. We also show that YY1 is a substrate of CARM1 mediated arginine methylation, where the latter could coactivate YY1 mediated reporter gene activation in vivo. Taken together, CARM1 and YY1 were found to regulate each other in a positive feedback loop to facilitate oral cancer progression.

11.
Sci Rep ; 8(1): 17120, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30451952

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

12.
Indian J Palliat Care ; 23(3): 231-236, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28827924

RESUMO

AIM: Breast cancer has become a pandemic with an ever-increasing incidence. Although better diagnostics and treatment modalities have reduced mortality, a large number of survivors face cancer and treatment-related long-term symptoms. Many survivors are taking up yoga for improving the quality of life (QoL). The present study attempts to evaluate predictors of psychological states in breast cancer survivors with long-term yoga experience. MATERIALS AND METHODS: A case-control study recruited early breast cancer survivors, 30-65 years, completing treatment > 6 months before recruitment, and grouped them based on prior yoga experience (BCY, n = 27) or naïve (BCN, n = 25). Demography, cancer history, diet, exercise habits, and yoga schedule were collected and tools to assess stress, anxiety, depression, general health, and QoL were administered. Multivariate linear regression was done to identify predictors of psychological variables. RESULTS: BCY had significantly lower stress, anxiety, depression, better general health, and QoL (P < 0.001). Global QoL and trait anxiety were significantly predicted by Yoga practice; depression was predicted by yoga practice, annual income, and sleep quality; state anxiety was predicted by Yoga practice and income; and stress was predicted by Yoga practice and sleep quality. CONCLUSION: Results indicate that breast cancer survivors, doing yoga, have better psychological profiles and are able to deal with demanding situations better. The psycho-oncogenic model of cancer etiology suggests that a better psychological state in survival has the potential to improve prognosis and survival outcomes and Yoga may be a suitable practice for staying cancer-free for a longer time.

13.
Sci Rep ; 5: 17621, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26639757

RESUMO

The ESRRA gene encodes a transcription factor and regulates several genes, such as WNT11 and OPN, involved in tumorigenesis. It is upregulated in several cancers, including OSCC. We have previously shown that the tumor suppressor miR-125a targets ESRRA, and its downregulation causes upregulation of ESRRA in OSCC. Upregulation of ESRRA in the absence of downregulation of miR-125a in a subset of OSCC samples suggests the involvement of an alternative mechanism. Using TaqMan(®) copy number assay, here we report for the first time that the genomic amplification of ESRRA causes its upregulation in a subset of OSCC samples. Ectopic overexpression of ESRRA led to accelerated cell proliferation, anchorage-independent cell growth and invasion, and inhibited apoptosis. Whereas, knockdown of ESRRA expression by siRNA led to reduced cell proliferation, anchorage-independent cell growth and invasion, and accelerated apoptosis. Furthermore, the delivery of a synthetic biostable ESRRA siRNA to OSCC cells resulted in regression of xenografts in nude mice. Thus, the genomic amplification of ESRRA is another novel mechanism for its upregulation in OSCC. Based on our in vitro and in vivo experiments, we suggest that targeting ESRRA by siRNA could be a novel therapeutic strategy for OSCC and other cancers.


Assuntos
Carcinoma de Células Escamosas/genética , Amplificação de Genes , Neoplasias Bucais/genética , Receptores de Estrogênio/genética , Regulação para Cima/genética , Apoptose/genética , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Genômica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Bucais/patologia , Invasividade Neoplásica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Estrogênio/metabolismo , Transcrição Gênica , Receptor ERRalfa Relacionado ao Estrogênio
14.
Indian J Surg Oncol ; 6(4): 415-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27065667

RESUMO

Breast cancer is the most common cancer in women worldwide. The clinical outcomes of which, have improved in the past decade, primarily due early diagnosis and multimodal management. Understanding of the disease biology with findings from omics-based research and molecular genetic characterization of the disease has been an important component of the therapy in the past 10 years. There is a need to understand the variations in individuals at the molecular level to enable in sub-classification of the different disease phenotypes and if possible to tailor the treatment to the patient. This article attempts to review the beneficial role of genetics in various facets of breast cancer management, in modern scientific medicine.

15.
J Biol Chem ; 289(46): 32276-32290, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25266720

RESUMO

Estrogen-related receptor α (ESRRA) functions as a transcription factor and regulates the expression of several genes, such as WNT11 and OPN. Up-regulation of ESRRA has been reported in several cancers. However, the mechanism underlying its up-regulation is unclear. Furthermore, the reports regarding the role and regulation of ESRRA in oral squamous cell carcinoma (OSCC) are completely lacking. Here, we show that tumor suppressor miR-125a directly binds to the 3'UTR of ESRRA and represses its expression. Overexpression of miR-125a in OSCC cells drastically reduced the level of ESRRA, decreased cell proliferation, and increased apoptosis. Conversely, the delivery of an miR-125a inhibitor to these cells drastically increased the level of ESRRA, increased cell proliferation, and decreased apoptosis. miR-125a-mediated down-regulation of ESRRA impaired anchorage-independent colony formation and invasion of OSCC cells. Reduced cell proliferation and increased apoptosis of OSCC cells were dependent on the presence of the 3'UTR in ESRRA. The delivery of an miR-125a mimic to OSCC cells resulted in marked regression of xenografts in nude mice, whereas the delivery of an miR-125a inhibitor to OSCC cells resulted in a significant increase of xenografts and abrogated the tumor suppressor function of miR-125a. We observed an inverse correlation between the expression levels of miR-125a and ESRRA in OSCC samples. In summary, up-regulation of ESRRA due to down-regulation of miR-125a is not only a novel mechanism for its up-regulation in OSCC, but decreasing the level of ESRRA by using a synthetic miR-125a mimic may have an important role in therapeutic intervention of OSCC and other cancers.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Receptor alfa de Estrogênio/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias Bucais/metabolismo , Sequência de Aminoácidos , Animais , Apoptose , Azacitidina/análogos & derivados , Azacitidina/química , Linhagem Celular Tumoral , Proliferação de Células , Decitabina , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Dados de Sequência Molecular , Invasividade Neoplásica , Transplante de Neoplasias , Plasmídeos/metabolismo , Ligação Proteica , Homologia de Sequência de Aminoácidos
17.
J Biol Chem ; 289(2): 968-76, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24257751

RESUMO

The Wilms tumor 1 gene (WT1) can either repress or induce the expression of genes. Inconsistent with its tumor suppressor role, elevated WT1 levels have been observed in leukemia and solid tumors. WT1 has also been suggested to act as an oncogene by inducing the expression of MYC and BCL-2. However, these are only the correlational studies, and no functional study has been performed to date. Consistent with its tumor suppressor role, CDC73 binds to RNA polymerase II as part of a PAF1 transcriptional regulatory complex and causes transcriptional repression of oncogenes MYC and CCND1. It also represses ß-catenin-mediated transcription. Based on the reduced level of CDC73 in oral squamous cell carcinoma (OSCC) samples in the absence of loss-of-heterozygosity, promoter methylation, and mutations, we speculated that an inhibitory transcription factor is regulating its expression. The bioinformatics analysis predicted WT1 as an inhibitory transcription factor to regulate the CDC73 level. Our results showed that overexpression of WT1 decreased CDC73 levels and promoted proliferation of OSCC cells. ChIP and EMSA results demonstrated binding of WT1 to the CDC73 promoter. The 5-azacytidine treatment of OSCC cells led to an up-regulation of WT1 with a concomitant down-regulation of CDC73, further suggesting regulation of CDC73 by WT1. Exogenous CDC73 attenuated the protumorigenic activity of WT1 by apoptosis induction. An inverse correlation between expression levels of CDC73 and WT1 was observed in OSCC samples. These observations indicated that WT1 functions as an oncogene by repressing the expression of CDC73 in OSCC. We suggest that targeting WT1 could be a therapeutic strategy for cancer, including OSCC.


Assuntos
Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Proteínas Supressoras de Tumor/genética , Proteínas WT1/genética , Adulto , Idoso , Sequência de Bases , Western Blotting , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Linhagem Celular Tumoral , Metilação de DNA , Feminino , Células HEK293 , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Neoplasias Bucais/terapia , Mutação , Regiões Promotoras Genéticas/genética , Ligação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Proteínas Supressoras de Tumor/metabolismo , Proteínas WT1/metabolismo
18.
Indian J Surg Oncol ; 5(4): 303-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25767345

RESUMO

The common patterns of dissemination and recurrence of rectal cancer are known and well documented. However extravisceral involvement is a relatively uncommon entity. Therefore, these metastases are not well studied in sufficiently large numbers to formulate evidence based recommendations regarding their optimal treatment. This report describes a case of carcinoma of the rectum metastatic to the oral cavity causing symptoms severe enough to necessitate operative management.

19.
PLoS One ; 8(3): e54643, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23472065

RESUMO

Mutations in the MCPH1 (microcephalin 1) gene, located at chromosome 8p23.1, result in two autosomal recessive disorders: primary microcephaly and premature chromosome condensation syndrome. MCPH1 has also been shown to be downregulated in breast, prostate and ovarian cancers, and mutated in 1/10 breast and 5/41 endometrial tumors, suggesting that it could also function as a tumor suppressor (TS) gene. To test the possibility of MCPH1 as a TS gene, we first performed LOH study in a panel of 81 matched normal oral tissues and oral squamous cell carcinoma (OSCC) samples, and observed that 14/71 (19.72%) informative samples showed LOH, a hallmark of TS genes. Three protein truncating mutations were identified in 1/15 OSCC samples and 2/5 cancer cell lines. MCPH1 was downregulated at both the transcript and protein levels in 21/41 (51.22%) and 19/25 (76%) OSCC samples respectively. A low level of MCPH1 promoter methylation was also observed in 4/40 (10%) tumor samples. We further observed that overexpression of MCPH1 decreased cellular proliferation, anchorage-independent growth in soft agar, cell invasion and tumor size in nude mice, indicating its tumor suppressive function. Using bioinformatic approaches and luciferase assay, we showed that the 3'-UTR of MCPH1 harbors two non-overlapping functional seed regions for miR-27a which negatively regulated its level. The expression level of miR-27a negatively correlated with the MCPH1 protein level in OSCC. Our study indicates for the first time that, in addition to its role in brain development, MCPH1 also functions as a tumor suppressor gene and is regulated by miR-27a.


Assuntos
Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , MicroRNAs/genética , Neoplasias Bucais/genética , Proteínas do Tecido Nervoso/genética , Animais , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Proteínas do Citoesqueleto , Células HeLa , Humanos , Perda de Heterozigosidade , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Invasividade Neoplásica , Transplante de Neoplasias
20.
J Biol Chem ; 288(1): 608-18, 2013 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-23166327

RESUMO

The CDC73 gene is mutationally inactivated in hereditary and sporadic parathyroid tumors. It negatively regulates ß-catenin, cyclin D1, and c-MYC. Down-regulation of CDC73 has been reported in breast, renal, and gastric carcinomas. However, the reports regarding the role of CDC73 in oral squamous cell carcinoma (OSCC) are lacking. In this study we show that CDC73 is down-regulated in a majority of OSCC samples. We further show that oncogenic microRNA-155 (miR-155) negatively regulates CDC73 expression. Our experiments show that the dramatic up-regulation of miR-155 is an exclusive mechanism for down-regulation of CDC73 in a panel of human cell lines and a subset of OSCC patient samples in the absence of loss of heterozygosity, mutations, and promoter methylation. Ectopic expression of miR-155 in HEK293 cells dramatically reduced CDC73 levels, enhanced cell viability, and decreased apoptosis. Conversely, the delivery of a miR-155 antagonist (antagomir-155) to KB cells overexpressing miR-155 resulted in increased CDC73 levels, decreased cell viability, increased apoptosis, and marked regression of xenografts in nude mice. Cotransfection of miR-155 with CDC73 in HEK293 cells abrogated its pro-oncogenic effect. Reduced cell proliferation and increased apoptosis of KB cells were dependent on the presence or absence of the 3'-UTR in CDC73. In summary, knockdown of CDC73 expression due to overexpression of miR-155 not only adds a novelty to the list of mechanisms responsible for its down-regulation in different tumors, but the restoration of CDC73 levels by the use of antagomir-155 may also have an important role in therapeutic intervention of cancers, including OSCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias Bucais/metabolismo , Neoplasias/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Regulação para Baixo , Células HEK293 , Células HeLa , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Plasmídeos/metabolismo
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