131 results on '"Ongkeko, Weg M."'
Search Results
102. Potential Role of Imatinib Mesylate (Gleevec, STI-571) in the Treatment of Vestibular Schwannoma
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Altuna, Xabier, primary, Lopez, Jay Patrick, additional, Yu, Michael Andrew, additional, Arandazi, Maria Jesus, additional, Harris, Jeffrey P., additional, Wang-Rodriguez, Jessica, additional, An, Yi, additional, Dobrow, Robert, additional, Doherty, Joni K., additional, and Ongkeko, Weg M., additional
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- 2011
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103. Abstract 4262: Characterization and regulation of a CXCR4-expressing subpopulation in head and neck cancer stem cells
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Kiang, Alan, primary, Abhold, Eric L., additional, Blair, Katherine J., additional, Yu, Michael A., additional, Haas, Martin, additional, Brumund, Kevin, additional, Weisman, Robert A., additional, and Ongkeko, Weg M., additional
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- 2010
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104. Abstract 4275: BMI-1 promotes drug resistance and cellular invasion in head and neck cancer stem cells
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Lew, Daniel, primary, Yi, David, additional, Wang-Rodriguez, Jessica, additional, Ahmad, Zana K., additional, Kiang, Alan, additional, Abhold, Eric L., additional, Haas, Martin, additional, Brumund, Kevin, additional, Weisman, Robert A., additional, and Ongkeko, Weg M., additional
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- 2010
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105. Abstract 3983: Real-time imaging of human thyroid cancer progression in a fluorescent orthotopic nude mouse model
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Cao, Hop S. Tran, primary, Kaushal, Sharmeela, additional, Snyder, Cynthia S., additional, Ongkeko, Weg M., additional, Hoffman, Robert M., additional, and Bouvet, Michael, additional
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- 2010
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106. Octamer 4 (Oct4) mediates chemotherapeutic drug resistance in liver cancer cells through a potential Oct4-AKT-ATP-binding cassette G2 pathway
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Wang, Xiao Qi, primary, Ongkeko, Weg M., additional, Chen, Lin, additional, Yang, Zhen Fan, additional, Lu, Ping, additional, Chen, Kwok Kin, additional, Lopez, Jay P., additional, Poon, Ronnie T.P., additional, and Fan, Sheung Tat, additional
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- 2010
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107. ABCG2: the key to chemoresistance in cancer stem cells?
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An, Yi, primary and Ongkeko, Weg M, additional
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- 2009
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108. A possible role of p73 on the modulation of p53 level through MDM2
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Wang, Xiaoqian, Ongkeko, Weg M., Lau, Anita Wan Sze, Leung, Kaman, Poon, Randy Yat Choi, Wang, Xiaoqian, Ongkeko, Weg M., Lau, Anita Wan Sze, Leung, Kaman, and Poon, Randy Yat Choi
- Abstract
MDM2, one of the transcriptional targets of p53, can target p53 for degradation in a negative feedback loop. The p53-related protein p73, however, can bind to MDM2 but is not consequently down-regulated. Here we demonstrate that p73 could transactivate the MDM2 promoter in p53-null cell lines. In p53-null cell lines, the level of MDM2 was increased by p73 due to increases in transcription and protein stability of MDM2. In transient transfection assays, inhibition of the transcriptional activity of p73 required a higher amount of MDM2 than that of p53. This is probably due to the fact that MDM2 can target p53, but not p73, for degradation. We demonstrated further that the level of p53 could be altered by a cooperation between MDM2 and p73, but not by transcriptional inactive mutants of p73. Expression of p73 resulted in a reduction of the ectopically expressed p53 in transient transfections or of the endogenous p53 induced by Adriamycin- or UV-mediated damage. These reductions of p53 were likely to be due to an increase in MDM2-mediated proteolysis. These results suggest the possibility that different levels of p73 in the cell may act as a mechanism to modulate p53 responses after DNA damage and other stresses and that an increase rather than a decrease in p73 may play a role in tumorigenesis.
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- 2001
109. Gefitinib (Iressa) Potentiates the Effect of Ionizing Radiation in Thyroid Cancer Cell Lines
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Lopez, Jay Patrick, primary, Wang-Rodriguez, Jessica, additional, Chang, Catherine Y., additional, Sneh, Gabriel, additional, Yu, Michael Andrew, additional, Pardo, Francisco S., additional, Aguilera, Joseph, additional, and Ongkeko, Weg M., additional
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- 2008
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110. MDM2 and MDMX bind and stabilize the p53-related protein p73
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Ongkeko, Weg M., Wang, Xiaoqian, Siu, Wai Yi, Lau, Anita Wan Sze, Yamashita, Katsumi, Harris, Adrian, Cox, Lynne S., Poon, Randy Yat Choi, Ongkeko, Weg M., Wang, Xiaoqian, Siu, Wai Yi, Lau, Anita Wan Sze, Yamashita, Katsumi, Harris, Adrian, Cox, Lynne S., and Poon, Randy Yat Choi
- Abstract
The p53 gene encodes one of the most important tumor suppressors in human cells and undergoes frequent mutational inactivation in cancers. MDM2, a transcriptional target of p53, binds p53 and can both inhibit p53-mediated transcription [1,2] and target p53 for proteasome-mediated proteolysis [3,4], A close relative of p53, p73, has recently been identified [5,6]. Here, we report that, like p53, p73 alpha and the alternative transcription product p73 beta also bind MDM2, Interaction between MDM2 and p53 represents a key step in the regulation of p53, as MDM2 promotes the degradation of p53. In striking contrast to p53, the half-life of p73 was found to be increased by binding to MDM2, Like MDM2, the MDM2-related protein MDMX also bound p73 and stabilized the level of p73, Moreover, the growth suppression functions of p73 and the induction of endogenous p21, a major mediator of the p53-dependent growth arrest pathway, were enhanced in the presence of MDM2, These differences between the regulation of p53 and p73 by MDM2/MDMX may highlight a physiological difference in their action.
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- 1999
111. STI-571 (Gleevec) Potentiates the Effect of Cisplatin in Inhibiting the Proliferation of Head and Neck Squamous Cell Carcinoma In Vitro
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Wang-Rodriguez, Jessica, primary, Lopez, Jay Patrick, additional, Altuna, Xabier, additional, Chu, Theresa S., additional, Weisman, Robert A., additional, and Ongkeko, Weg M., additional
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- 2006
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112. Gleevec Suppresses p63 Expression in Head and Neck Squamous Cell Carcinoma Despite p63 Activation by DNA-Damaging Agents
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Ongkeko, Weg M., primary, An, Yi, additional, Chu, Theresa S., additional, Aguilera, Joseph, additional, Dang, Christopher L., additional, and Wang-Rodriguez, Jessica, additional
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- 2006
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113. EGFR Regulates the Side Population in Head and Neck Squamous Cell Carcinoma
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Chen, Jocelyn S., primary, Pardo, Francisco S., additional, Wang-Rodriguez, Jessica, additional, Chu, Theresa S., additional, Lopez, Jay Patrick, additional, Aguilera, Joseph, additional, Altuna, Xabier, additional, Weisman, Robert A., additional, and Ongkeko, Weg M., additional
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- 2006
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114. Expression of Protein Tyrosine Kinases in Head and Neck Squamous Cell Carcinomas
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Ongkeko, Weg M., primary, Altuna, Xabier, additional, Weisman, Robert A., additional, and Wang-Rodriguez, Jessica, additional
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- 2005
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115. MDM2 and MDMX bind and stabilize the p53-related protein p73
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Ongkeko, Weg M., primary, Wang, Xiao Qi, additional, Siu, Wai Yi, additional, Lau, Anita W.S., additional, Yamashita, Katsumi, additional, Harris, Adrian L., additional, Cox, Lynne S., additional, and Poon, Randy Y.C., additional
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- 1999
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116. Nicotine Promotes Acquisition of Stem Cell and Epithelial-to-Mesenchymal Properties in Head and Neck Squamous Cell Carcinoma.
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Michael Andrew Yu, Alan Kiang, Wang-Rodriguez, Jessica, Rahimy, Elham, Haas, Martin, Vicky Yu, Ellies, Lesley G., Jing Chen, Jian-Bing Fan, Brumund, Kevin T., Weisman, Robert A., and Ongkeko, Weg M.
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NICOTINE ,ALKALOIDS ,NICOTINIC agonists ,PYRIDINE ,TOBACCO ,STEM cells - Abstract
The ability of nicotine to enhance the malignancy of cancer cells is known; however, the possibility that nicotine could regulate a cancer stem cell phenotype remains to be well-established. In this study we sought to determine whether longterm exposure to nicotine could promote cancer stem cell-like properties in two head and neck squamous cell carcinoma cell lines, UMSCC-10B and HN-1. Nicotine treatment induced epithelial-to-mesenchymal transition (EMT) in both cell lines by repressing E-cadherin expression, and led to the induction of stem cell markers Oct-4, Nanog, CD44 and BMI-1, which was reversed upon ectopic re-expression of E-cadherin. Nicotine-treated cells formed spheres at a higher efficiency than nontreated cells, formed larger tumors when injected into mice, and formed tumors with 4-fold greater efficiency compared to control cells when injected at limiting doses. Consistent with previous literature, nicotine-treated cells demonstrated a greater capacity for survival and also a higher tendency to invade. Comparison of microRNA profiles between nicotine and control cells revealed the upregulation of miR-9, a repressor of E-cadherin, and the downregulation of miR-101, a repressor of EZH2. Taken together, these results suggest that nicotine may play a critical role in the development of tobacco-induced cancers by regulating cancer stem cell characteristics, and that these effects are likely mediated through EMT-promoting, microRNA-mediated pathways. Further characterization of such pathways remains a promising avenue for the understanding and treatment of tobacco-related cancers. [ABSTRACT FROM AUTHOR]
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- 2012
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117. COVID-19 Severity Potentially Modulated by Cardiovascular-Disease-Associated Immune Dysregulation.
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Lee, Abby C., Castaneda, Grant, Li, Wei Tse, Chen, Chengyu, Shende, Neil, Chakladar, Jaideep, Taub, Pam R., Chang, Eric Y., and Ongkeko, Weg M.
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PATIENT-ventilator dyssynchrony ,COVID-19 ,MONONUCLEAR leukocytes ,CORONARY artery disease ,GENE expression profiling ,MYOCARDIUM ,BLOOD platelets - Abstract
Patients with underlying cardiovascular conditions are particularly vulnerable to severe COVID-19. In this project, we aimed to characterize similarities in dysregulated immune pathways between COVID-19 patients and patients with cardiomyopathy, venous thromboembolism (VTE), or coronary artery disease (CAD). We hypothesized that these similarly dysregulated pathways may be critical to how cardiovascular diseases (CVDs) exacerbate COVID-19. To evaluate immune dysregulation in different diseases, we used four separate datasets, including RNA-sequencing data from human left ventricular cardiac muscle samples of patients with dilated or ischemic cardiomyopathy and healthy controls; RNA-sequencing data of whole blood samples from patients with single or recurrent event VTE and healthy controls; RNA-sequencing data of human peripheral blood mononuclear cells (PBMCs) from patients with and without obstructive CAD; and RNA-sequencing data of platelets from COVID-19 subjects and healthy controls. We found similar immune dysregulation profiles between patients with CVDs and COVID-19 patients. Interestingly, cardiomyopathy patients display the most similar immune landscape to COVID-19 patients. Additionally, COVID-19 patients experience greater upregulation of cytokine- and inflammasome-related genes than patients with CVDs. In all, patients with CVDs have a significant overlap of cytokine- and inflammasome-related gene expression profiles with that of COVID-19 patients, possibly explaining their greater vulnerability to severe COVID-19. [ABSTRACT FROM AUTHOR]
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- 2021
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118. p53 Regulates the Minimal Promoter of the Human Topoisomerase IIα Gene.
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Sandri, M. Ines, Isaacs, Richard J., Ongkeko, Weg M., Harris, Adrian L., Hickson, Ian D., Broggini, Massimo, and Vikhanskaya, Faina
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- 1996
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119. Protein Expression of the Tumor Suppressors p16INK4A and p53 and Disease Progression in Recurrent Respiratory Papillomatosis
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Pham, Truc T., Ongkeko, Weg M., An, Yi, and Yi, Eunhee S.
- Abstract
Background:Recurrent respiratory papillomatosis (RRP) is a benign condition that rarely metastasizes as invasive squamous cell carcinoma. Although this disease is associated with human papillomavirus, the role of this virus in tumorigenesis is unclear.
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- 2007
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120. Construction and Validation of a Prognostic Gene-Based Model for Overall Survival Prediction in Hepatocellular Carcinoma Using an Integrated Statistical and Bioinformatic Approach.
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Dessie, Eskezeia Yihunie, Tu, Siang-Jyun, Chiang, Hui-Shan, Tsai, Jeffrey J.P., Chang, Ya-Sian, Chang, Jan-Gowth, Ng, Ka-Lok, and Ongkeko, Weg M.
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HEPATOCELLULAR carcinoma ,RECEIVER operating characteristic curves ,GENES ,SURVIVAL analysis (Biometry) ,DIAGNOSIS - Abstract
Hepatocellular carcinoma (HCC) is one of the most common lethal cancers worldwide and is often related to late diagnosis and poor survival outcome. More evidence is demonstrating that gene-based prognostic models can be used to predict high-risk HCC patients. Therefore, our study aimed to construct a novel prognostic model for predicting the prognosis of HCC patients. We used multivariate Cox regression model with three hybrid penalties approach including least absolute shrinkage and selection operator (Lasso), adaptive lasso and elastic net algorithms for informative prognostic-related genes selection. Then, the best subset regression was used to identify the best prognostic gene signature. The prognostic gene-based risk score was constructed using the Cox coefficient of the prognostic gene signature. The model was evaluated by Kaplan–Meier (KM) and receiver operating characteristic curve (ROC) analyses. A novel four-gene signature associated with prognosis was identified and the risk score was constructed based on the four-gene signature. The risk score efficiently distinguished the patients into a high-risk group with poor prognosis. The time-dependent ROC analysis revealed that the risk model had a good performance with an area under the curve (AUC) of 0.780, 0.732, 0.733 in 1-, 2- and 3-year prognosis prediction in The Cancer Genome Atlas (TCGA) dataset. Moreover, the risk score revealed a high diagnostic performance to classify HCC from normal samples. The prognosis and diagnosis prediction performances of risk scores were verified in external validation datasets. Functional enrichment analysis of the four-gene signature and its co-expressed genes involved in the metabolic and cell cycle pathways was constructed. Overall, we developed a novel-gene-based prognostic model to predict high-risk HCC patients and we hope that our findings can provide promising insight to explore the role of the four-gene signature in HCC patients and aid risk classification. [ABSTRACT FROM AUTHOR]
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- 2021
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121. The renal clear cell carcinoma immune landscape.
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Saad, Omar A., Li, Wei Tse, Krishnan, Aswini R., Nguyen, Griffith C., Lopez, Jay P., McKay, Rana R., Wang-Rodriguez, Jessica, and Ongkeko, Weg M.
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RENAL cell carcinoma , *LANDSCAPES - Abstract
A comprehensive evaluation of the clear cell renal cell carcinoma (ccRCC) immune landscape was found using 584 RNA-sequencing datasets from The Cancer Genome Atlas (TCGA), we identified 17 key dysregulated immune-associated genes in ccRCC based on association with clinical variables and important immune pathways. Of the numerous findings from our analyses, we found that several of the 17 key dysregulated genes are heavily involved in interleukin and NF-kB signaling and that somatic copy number alteration (SCNA) hotspots may be causally associated with gene dysregulation. More importantly, we also found that key immune-associated genes and pathways are strongly upregulated in ccRCC. Our study may lend novel insights into the clinical implications of immune dysregulation in ccRCC and suggests potential immunotherapeutic targets for further evaluation. [ABSTRACT FROM AUTHOR]
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- 2022
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122. Functional Genomics Profiling of Bladder Urothelial Carcinoma MicroRNAome as a Potential Biomarker.
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Wei Tse Li, Hao Zheng, Nguyen, Vincent, Wang-Rodriguez, Jessica, and Ongkeko, Weg M.
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BLADDER cancer genetics , *MICRORNA , *BLADDER cancer diagnosis , *RNA sequencing , *TRANSITIONAL cell carcinoma - Abstract
Though bladder urothelial carcinoma is the most common form of bladder cancer, advances in its diagnosis and treatment have been modest in the past few decades. To evaluate miRNAs as putative disease markers for bladder urothelial carcinoma, this study develops a process to identify dysregulated miRNAs in cancer patients and potentially stratify patients based on the association of their microRNAome phenotype to genomic alterations. Using RNA sequencing data for 409 patients from the Cancer Genome Atlas, we examined miRNA differential expression between cancer and normal tissues and associated differentially expressed miRNAs with patient survival and clinical variables. We then correlated miRNA expressions with genomic alterations using the Wilcoxon test and REVEALER. We found a panel of six miRNAs dysregulated in bladder cancer and exhibited correlations to patient survival. We also performed differential expression analysis and clinical variable correlations to identify miRNAs associated with tobacco smoking, the most important risk factor for bladder cancer. Two miRNAs, miR- 323a and miR-431, were differentially expressed in smoking patients compared to nonsmoking patients and were associated with primary tumor size. Functional studies of these miRNAs and the genomic features we identified for potential stratification may reveal underlying mechanisms of bladder cancer carcinogenesis and further diagnosis and treatment methods for urothelial bladder carcinoma. [ABSTRACT FROM AUTHOR]
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- 2018
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123. Assessing the diagnostic utility of tRNA-derived fragments as biomarkers of head and neck cancer.
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Uzelac M and Ongkeko WM
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Roughly 54,000 individuals are diagnosed with head and neck cancers in the United States yearly. Transfer RNA-derived fragments (tRF) are the products of enzymatic cleavage of precursor tRNAs, and have been proposed for use as biomarkers of head and neck cancer. In this study, we aim to further analyze the utility that tRFs might provide as biomarkers of head and neck cancer. tRF read counts were obtained for 453 tumor and 44 adjacent normal tissue samples and used to construct a gradient boosting diagnostic model. Although we identified 129 tRFs that were significantly dysregulated between these samples, the model achieved a sensitivity of only 69 % and a specificity of 59 %. tRFs are thought to induce the degradation of mRNA transcripts containing a complementary "seed" region. Despite the above performances, we chose to explore this concept of translational regulation by analyzing these tRFs for inverse correlation to the expression of select oncogenes and tumor suppressor genes implicated in head and neck cancer. Among others, CysGCA 5'-half and LysCTT 3'-tRF were upregulated in the tumor samples, and corresponded to decreased expression of PIK3R1, AKT1, and CPEB3. These transcripts were further found to contain numerous significantly complementary sites at which tRF-mediated mRNA degradation might occur. Although these tRFs did appear to correlate to many of the oncogenic metrics analyzed, we believe that additional research is needed before they might be used to improve the diagnosis, treatment, and survival of patients with this disease., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)
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- 2024
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124. The intratumor microbiome varies by geographical location and anatomical site in head and neck squamous cell carcinoma.
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Yalamarty R, Magesh S, John D, Chakladar J, Li WT, Brumund KT, Wang-Rodriguez J, and Ongkeko WM
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- Humans, Tumor Microenvironment, Squamous Cell Carcinoma of Head and Neck microbiology, Squamous Cell Carcinoma of Head and Neck pathology, Head and Neck Neoplasms microbiology, Head and Neck Neoplasms pathology, Microbiota
- Abstract
Head and Neck Squamous Cell Carcinoma (HNSCC) is a highly heterogeneous cancer that is characterized by distinct phenotypes based on anatomical site and etiological agents. Recently, the intratumor microbiome has been implicated in cancer pathogenesis and progression. Although it is well established that the gut microbiome varies with geographical location and is highly influenced by factors such as diet, environment, and genetics, the intratumor microbiome is not very well characterized. In this review, we aim to characterize the HNSCC intratumor microbiome by geographical location and anatomical site. We conducted a review of primary literature from PubMed and assessed studies based on relevancy and recency. To the best of our knowledge, we are the first to comprehensively examine the tumor microenvironment of HNSCC with respect to these two primary factors on a large scale. Our results suggest that there are unique bacterial and fungal biomarkers for HNSCC for each of the following geographical locations: North America, Asia, Europe, Australia, and Africa. We also identified a panel of microbial biomarkers that are unique to two primary HNSCC anatomic sites, as well as microbial biomarkers associated with various etiological agents of HNSCC. Future study of these microbes may improve HNSCC diagnostic and therapeutic modalities by accounting for differences based on geographic regions and anatomical sites., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: This work was funded by the University of California Academic Senate San Diego Division [RG104647] to Weg M. Ongkeko., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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125. Clinical characteristics and comorbidities associated with SARS-CoV-2 breakthrough infection in the University of California Healthcare Systems.
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Hogarth M, John D, Li Y, Wang-Rodriguez J, Chakladar J, Li WT, Mehta SR, Jain S, and Ongkeko WM
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- Humans, SARS-CoV-2, Breakthrough Infections, Comorbidity, Essential Hypertension, COVID-19 Vaccines, COVID-19 epidemiology
- Abstract
Background: To evaluate the degree to which clinical comorbidities or combinations of comorbidities are associated with SARS-CoV-2 breakthrough infection., Materials and Methods: A breakthrough infection was defined as a positive test at least 14 days after a full vaccination regimen. Logistic regression was used to calculate aORs, which were adjusted for age, sex, and race information., Results: A total of 110,380 patients from the UC CORDS database were included. After adjustment, stage 5 CKD due to hypertension (aOR: 7.33; 95% CI: 4.86-10.69; p<.001; power=1) displayed higher odds of infection than any other comorbidity. Lung transplantation history (aOR: 4.79; 95% CI: 3.25-6.82; p<.001; power= 1), coronary atherosclerosis (aOR: 2.12; 95% CI: 1.77-2.52; p<.001; power=1), and vitamin D deficiency (aOR: 1.87; 95% CI: 1.69-2.06; p<.001; power=1) were significantly correlated to breakthrough infection. Patients with obesity in addition to essential hypertension (aOR: 1.74; 95% CI: 1.51-2.01; p<.001; power=1) and anemia (aOR: 1.80; 95% CI: 1.47-2.19; p<.001; power=1) were at additional risk of breakthrough infection compared to those with essential hypertension and anemia alone., Conclusions: Further measures should be taken to prevent breakthrough infection for individuals with these conditions, such as acquiring additional doses of the SARS-CoV-2 vaccine to boost immunity., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2023
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126. Randomised controlled trial of real-time feedback and brief coaching to reduce indoor smoking.
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Hovell MF, Bellettiere J, Liles S, Nguyen B, Berardi V, Johnson C, Matt GE, Malone J, Boman-Davis MC, Quintana PJE, Obayashi S, Chatfield D, Robinson R, Blumberg EJ, Ongkeko WM, Klepeis NE, and Hughes SC
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- Adult, Child, Child, Preschool, Feedback, Female, Humans, Infant, Interrupted Time Series Analysis, Male, Mentoring methods, Nicotine analysis, Vaping prevention & control, Young Adult, Air Pollution, Indoor analysis, Smoking Prevention methods, Tobacco Smoke Pollution analysis, Tobacco Smoking prevention & control
- Abstract
Background: Previous secondhand smoke (SHS) reduction interventions have provided only delayed feedback on reported smoking behaviour, such as coaching, or presenting results from child cotinine assays or air particle counters., Design: This SHS reduction trial assigned families at random to brief coaching and continuous real-time feedback (intervention) or measurement-only (control) groups., Participants: We enrolled 298 families with a resident tobacco smoker and a child under age 14., Intervention: We installed air particle monitors in all homes. For the intervention homes, immediate light and sound feedback was contingent on elevated indoor particle levels, and up to four coaching sessions used prompts and praise contingent on smoking outdoors. Mean intervention duration was 64 days., Measures: The primary outcome was 'particle events' (PEs) which were patterns of air particle concentrations indicative of the occurrence of particle-generating behaviours such as smoking cigarettes or burning candles. Other measures included indoor air nicotine concentrations and participant reports of particle-generating behaviour., Results: PEs were significantly correlated with air nicotine levels (r=0.60) and reported indoor cigarette smoking (r=0.51). Interrupted time-series analyses showed an immediate intervention effect, with reduced PEs the day following intervention initiation. The trajectory of daily PEs over the intervention period declined significantly faster in intervention homes than in control homes. Pretest to post-test, air nicotine levels, cigarette smoking and e-cigarette use decreased more in intervention homes than in control homes., Conclusions: Results suggest that real-time particle feedback and coaching contingencies reduced PEs generated by cigarette smoking and other sources., Trial Registration Number: NCT01634334; Post-results., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2020
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127. Evaluation of non-coding RNAs as potential targets in head and neck squamous cell carcinoma cancer stem cells.
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Rahimy E, Kuo SZ, and Ongkeko WM
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- Antineoplastic Agents pharmacology, Carcinoma, Squamous Cell drug therapy, Carcinoma, Squamous Cell genetics, Gene Expression Regulation, Neoplastic, Head and Neck Neoplasms drug therapy, Head and Neck Neoplasms genetics, Humans, MicroRNAs antagonists & inhibitors, MicroRNAs genetics, MicroRNAs metabolism, Neoplastic Stem Cells drug effects, RNA, Long Noncoding antagonists & inhibitors, RNA, Long Noncoding genetics, RNA, Long Noncoding metabolism, RNA, Small Interfering antagonists & inhibitors, RNA, Small Interfering genetics, RNA, Small Interfering metabolism, RNA, Small Nucleolar antagonists & inhibitors, RNA, Small Nucleolar genetics, RNA, Small Nucleolar metabolism, RNA, Untranslated antagonists & inhibitors, Signal Transduction drug effects, Squamous Cell Carcinoma of Head and Neck, Carcinoma, Squamous Cell pathology, Head and Neck Neoplasms pathology, Neoplastic Stem Cells metabolism, RNA, Untranslated genetics, RNA, Untranslated metabolism
- Abstract
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer in the world and has not seen improved survival rates over the past few decades. Current treatment plans include surgery, radiation therapy, and chemotherapy, but these are relatively ineffective options for recurrent or metastatic tumors. Therefore, there is a high priority for new therapies that specifically target the resistant HNSCC cancer stem cells (CSCs), a subpopulation responsible for tumor initiation and metastasis. Given their vast effects on gene expression and biological processes, including stem cell capabilities, non-coding RNAs (ncRNAs) have become a promising new repertoire of genes to investigate as potential diagnostic or therapeutic targets. This review presents a comprehensive overview of current investigative studies that can contribute to our understanding of the still tentative link between ncRNA and the biology of HNSCC cancer stem cells. In doing so, we aim to analyze the potential role of stem cell-related ncRNAs in the development of molecularly targeted cancer therapy for HNSCC. Although the majority of updated knowledge on HNSCC and ncRNA focuses heavily on microRNA, we chose to give considerable attention to the promise of other classes of ncRNAs (lncRNA, piRNA, and snoRNA), many of which are not yet well characterized or are yet to be discovered, and thus represent a potentially exciting and untapped pool of molecular targets or biomarkers in HNSCC therapy.
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- 2014
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128. Real-time imaging of tumor progression in a fluorescent orthotopic mouse model of thyroid cancer.
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Tran Cao HS, Kaushal S, Snyder CS, Ongkeko WM, Hoffman RM, and Bouvet M
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- Animals, Cell Line, Tumor, Disease Progression, Female, Green Fluorescent Proteins, Humans, Luminescent Proteins, Mice, Mice, Nude, Whole Body Imaging, Red Fluorescent Protein, Carcinoma diagnosis, Carcinoma, Papillary diagnosis, Diagnostic Imaging, Disease Models, Animal, Fluorescent Dyes, Thyroid Neoplasms diagnosis
- Abstract
There is a need for a clinically relevant mouse model of thyroid cancer that enables real-time, non-invasive monitoring of tumor growth, progression, and drug response over time. Human thyroid cancer cell lines NPA (papillary) and KAK-1 (anaplastic) were stably transfected to express either red or green fluorescent protein. Cancer cells were injected into the thyroid glands of 8-week-old athymic mice. The animals were imaged with whole-body fluorescence imaging weekly and sacrificed when premorbid. At necropsy, the primary tumor was resected en bloc with the respiratory system for processing and analysis. Histology was performed on fixed tissue specimens for review of morphologic findings. Both anaplastic and papillary thyroid cancer cell lines led to robust development of orthotopic fluorescent tumors in nude mice. Injection of 5×10(5) cancer cells was sufficient for tumor development. Tumors were visualized for both cell lines via non-invasive imaging as early as 3 weeks post-implantation and were monitored over time. Time to premorbid condition varied between mice and was associated with a primary tumor growth pattern (early local compression of the esophagus vs. late metastatic disease) rather than tumor size. At necropsy, tumor fluorescence demonstrated metastases in the lungs, lymph nodes and vessels that were not visible under white light. Thus an orthotopic mouse model of thyroid cancer has been developed that replicates the major clinical features of thyroid cancer and enables real-time, non-invasive monitoring of tumor progression. This model should permit preclinical evaluation of novel thyroid cancer therapeutics.
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- 2010
129. p73 expression and function in vestibular schwannoma.
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Ahmad ZK, Altuna X, Lopez JP, An Y, Wang-Rodriguez J, Juneja VR, Chen JS, Arandazi MJ, Aguilera J, Harris JP, and Ongkeko WM
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- Adult, Aged, Annexin A5 analysis, Apoptosis physiology, Blotting, Western, Cell Cycle physiology, Cell Line, Tumor, DNA-Binding Proteins metabolism, Female, Flow Cytometry, Genetic Therapy, Humans, Immunohistochemistry, In Situ Nick-End Labeling, Male, Middle Aged, Neuroma, Acoustic therapy, Nuclear Proteins metabolism, Papillomavirus E7 Proteins, Retrospective Studies, Transfection, Tumor Protein p73, Tumor Suppressor Proteins metabolism, DNA-Binding Proteins physiology, Gene Expression Regulation, Neoplastic physiology, Neuroma, Acoustic metabolism, Nuclear Proteins physiology, Oncogene Proteins, Viral genetics, Protein-Tyrosine Kinases genetics, Repressor Proteins genetics, Tumor Suppressor Proteins physiology
- Abstract
Objectives: To determine the expression of the p53 family member p73 in vestibular schwannoma (VS) and to determine the potential role of this tumor suppressor in regulating the proliferation of HEI193, a human papillomavirus E6-E7 immortalized VS cell line., Methods: Immunohistochemical staining was used to investigate the expression of p73 in 34 cases of archived VS tissue, while Western blot analysis and immunofluorescence were performed to demonstrate the expression and localization of p73 in HEI193. After transfection of a full-length p73 plasmid (TAp73alpha), flow cytometry analysis was performed to determine the effect of p73 expression on cell cycle distribution, while annexin V-FITC (fluorescein isothiocyanate) analysis and TUNEL (terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling) assay were used to measure apoptosis. The effect of p73 expression on ionizing radiation-induced cell death was also investigated with annexin V staining, TUNEL assay, and flow cytometry analysis., Results: Of the 34 vestibular schwannoma tissues examined, p73 was expressed in 14 (41%) but was not expressed in HEI193. Transfection of p73 alone resulted in increased apoptosis and necrosis, and G(1) accumulation with concomitant induction of p21. The presence of p73 also significantly increased early apoptosis (P = .046), late apoptosis (P < .001), and necrosis (P = .009) on exposure of the HEI193 cells to ionizing radiation., Conclusion: Forced expression of p73, perhaps by gene therapy, to induce apoptosis directly or to sensitize VS tumors to ionizing radiation may have relevant therapeutic applications.
- Published
- 2009
- Full Text
- View/download PDF
130. Imatinib-mediated inactivation of Akt regulates ABCG2 function in head and neck squamous cell carcinoma.
- Author
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Chu TS, Chen JS, Lopez JP, Pardo FS, Aguilera J, and Ongkeko WM
- Subjects
- ATP Binding Cassette Transporter, Subfamily G, Member 2, Benzamides, Blotting, Western, Carcinoma, Squamous Cell metabolism, Cell Line, Tumor, Down-Regulation, Drug Resistance, Neoplasm, Flow Cytometry, Fluorescent Antibody Technique, Head and Neck Neoplasms metabolism, Humans, Imatinib Mesylate, Immunoprecipitation, Neoplasm Proteins, ATP-Binding Cassette Transporters antagonists & inhibitors, Antineoplastic Agents pharmacology, Carcinoma, Squamous Cell drug therapy, Doxorubicin pharmacology, Head and Neck Neoplasms drug therapy, Piperazines pharmacology, Proto-Oncogene Proteins c-akt, Pyrimidines pharmacology
- Abstract
Objective: To investigate whether the mechanism for the reversal of ABCG2 (also known as ABCP, MXR, and BCRP)-mediated drug resistance by imatinib mesylate (Gleevec, STI571; Novartis Pharmaceuticals Corp, East Hanover, New Jersey) is caused by the downregulation of Akt kinase. The adenosine triphosphatase-binding cassette protein ABCG2 has been suggested to be involved in the resistance against various anticancer drugs. Recent studies show that imatinib reverses ABCG2-mediated drug resistance to topotecan hydrochloride and SN-38. In addition, we have previously reported that imatinib downregulates Akt kinase activity, which is elevated in head and neck squamous cell carcinoma., Design: Flow cytometric analysis was used to determine the levels of drug or dye extrusion from the cells., Results: We used Akt kinase inhibitors, transfection with short interfering RNA (siRNA) Akt, and the tyrosine kinase inhibitor imatinib to show that these treatments decreased the side population by 50% to 70% in Hoechst 33342 extrusion studies. Doxorubicin hydrochloride extrusion experiments also demonstrated 20% to 26% decrease in doxorubicin efflux on cells treated with imatinib, 1L6-hydroxymethyl-chiro-inositol 2-(R)-2-O-methyl-3-O-octadecylcarbonate, and transfection with siRNA Akt. With Western blot and immunofluorescence experiments, our data suggest that ABCG2 translocation is the mechanism by which imatinib and Akt regulate drug resistance. Clonogenic survival assays performed with imatinib-treated cells resulted in a dose-dependent decrease in cell survival compared with the control population., Conclusion: Our findings demonstrate that imatinib confers greater doxorubicin retention, presumably via inhibition of Akt, which regulates ABCG2 function.
- Published
- 2008
- Full Text
- View/download PDF
131. Gefitinib inhibition of drug resistance to doxorubicin by inactivating ABCG2 in thyroid cancer cell lines.
- Author
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Lopez JP, Wang-Rodriguez J, Chang C, Chen JS, Pardo FS, Aguilera J, and Ongkeko WM
- Subjects
- ATP Binding Cassette Transporter, Subfamily G, Member 2, ATP-Binding Cassette Transporters antagonists & inhibitors, ATP-Binding Cassette Transporters metabolism, Antineoplastic Agents therapeutic use, Apoptosis drug effects, Biomarkers, Tumor genetics, Biomarkers, Tumor metabolism, Blotting, Western, Carcinoma drug therapy, Carcinoma metabolism, Carcinoma pathology, Cell Line, Tumor, Cell Proliferation drug effects, Culture Media, Doxorubicin administration & dosage, Drug Resistance, Multiple, ErbB Receptors antagonists & inhibitors, ErbB Receptors metabolism, Flow Cytometry, Fluorescent Antibody Technique, Gefitinib, Humans, In Situ Nick-End Labeling, Neoplasm Proteins antagonists & inhibitors, Neoplasm Proteins metabolism, Quinazolines administration & dosage, Thyroid Neoplasms metabolism, Thyroid Neoplasms pathology, ATP-Binding Cassette Transporters genetics, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Drug Resistance, Neoplasm drug effects, Gene Expression Regulation, Neoplastic, Neoplasm Proteins genetics, RNA, Neoplasm genetics, Thyroid Neoplasms drug therapy
- Abstract
Objective: To investigate the regulation of the breast cancer resistance protein ABCG2/BRCP1 drug transporter by epidermal growth factor receptor (EGFR) kinase activity, and to determine whether gefitinib, an EGFR small molecule inhibitor, will modulate the effects of doxorubicin hydrochloride by inhibiting its extrusion from thyroid cancer cells., Design: Extrusion assays using flow cytometry analysis were used to determine the ability of thyroid cancer cells to extrude the chemotherapy drug, doxorubicin, via the ABCG2 drug transporter in the presence or absence of gefitinib. Immunofluorescence was employed to determine the cellular expression of ABCG2. The ABCG2 expression in ARO and WRO cell lines was analyzed by Western blot analysis. Inactivation of EGFR kinase by gefitinib was analyzed by Western blot analysis and immunofluorescence. A terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assay was performed to demonstrate ABCG2-mediated apoptosis in the presence of doxorubicin. Colony formation assays were performed to determine the effect of gefitinib on thyroid cancer cell survival in response to gefitinib, doxorubicin, or the combination of both drugs., Results: Inhibition of EGFR kinase activity by gefitinib causes the translocation of the ABCG2 drug transporter away from the plasma membrane, resulting in a concomitant decrease in doxorubicin extrusion in thyroid cancer cell lines. Both ARO and WRO demonstrated differential ABCG2 expression, whereas both were sensitized to doxorubicin-induced apoptosis on ABCG2 knockdown with short interfering RNA. The addition of gefitinib increases doxorubicin-induced cell death in thyroid cancer cells as measured by colony formation assay., Conclusions: Epidermal growth factor receptor regulates the function of the drug transporter ABCG2/BCRP1 and correlates with ABCG2 protein expression levels. Inactivation of the EGFR kinase by gefitinib potentiates the cytotoxic effect of doxorubicin in thyroid cancer, most likely by decreasing the ability of the cell to extrude doxorubicin. The expression of ABCG2 may explain in part the ineffectiveness of doxorubicin as a single modality treatment for anaplastic thyroid cancer or for treatment of metastatic follicular thyroid cancer. Use of this combination treatment of gefitinib and doxorubicin may be a promising therapy for anaplastic thyroid and metastatic follicular thyroid cancer and needs to be investigated further.
- Published
- 2007
- Full Text
- View/download PDF
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