390 research outputs found

    Alterations in cellular metabolism modulate CD1d-mediated NKT-cell responses

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    Natural killer T (NKT) cells play a critical role in the host's innate immune response. CD1d-mediated presentation of glycolipid antigens to NKT cells has been established; however, the mechanisms by which NKT cells recognize infected or cancerous cells remain unclear. 5â€Č-AMP activated protein kinase (AMPK) is a master regulator of lipogenic pathways. We hypothesized that activation of AMPK during infection and malignancy could alter the repertoire of antigens presented by CD1d and serve as a danger signal to NKT cells. In this study, we examined the effect of alterations in metabolism on CD1d-mediated antigen presentation to NKT cells and found that an infection with lymphocytic choriomeningitis virus rapidly increased CD1d-mediated antigen presentation. Hypoxia inducible factors (HIF) enhance T-cell effector functions during infection, therefore antigen presenting cells pretreated with pharmacological agents that inhibit glycolysis, induce HIF and activate AMPK were assessed for their ability to induce NKT-cell responses. Pretreatment with 2-deoxyglucose, cobalt chloride, AICAR and metformin significantly enhanced CD1d-mediated NKT-cell activation. In addition, NKT cells preferentially respond to malignant B cells and B-cell lymphomas express HIF-1α. These data suggest that targeting cellular metabolism may serve as a novel means of inducing innate immune responses

    Classification of TP53 mutations and HPV predict survival in advanced larynx cancer

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134126/1/lary25915-sup-0001-suppinfo.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134126/2/lary25915_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134126/3/lary25915.pd

    Human papillomavirus–related oropharyngeal cancer: HPV and p16 status in the recurrent versus parent tumor

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    Background Although typically associated with a favorable prognosis, a minority of human papillomavirus (HPV)‐related (+) oropharyngeal cancers recur after chemoradiation. We postulated that a minor HPV‐negative tumor subfraction may be responsible for recurrences of HPV+ oropharyngeal cancer. Methods Paired untreated primary and recurrent tumor specimens were identified for 37 patients with oropharyngeal cancer who received definitive chemoradiotherapy at our institution. Concordance in HPV/p16 expression between primary and recurrent tumors was assessed. Results Among 31 patients with HPV+/p16+ primary tumors, 30 (97%) retained evidence of both HPV and p16 expression at recurrence (27 HPV+/p16+; 3 HPV+/p16‐partial). One (3%) initially HPV+/p16+ patient developed an HPV‐negative/p16‐negative lung squamous cell carcinoma (SCC), representing either a discordant oropharyngeal cancer metastasis or second primary tumor. Conclusion HPV‐related oropharyngeal cancers retain HPV+/p16+ expression at recurrence. Our results fail to provide evidence that a minor HPV‐negative tumor subfraction is responsible for biologically aggressive behavior of HPV+ oropharyngeal cancer that recurs after chemoradiation. © 2014 Wiley Periodicals, Inc. Head Neck 37 : 8–11, 2015Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109811/1/hed23548.pd

    Matted nodes: Poor prognostic marker in oropharyngeal squamous cell carcinoma independent of HPV and EGFR status

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    Background Despite better prognosis, there is a group of oropharyngeal squamous cell carcinoma (SCC) human papillomavirus (HPV)+ patients who experience treatment failure and succumb to distant metastasis. Methods Seventy‐eight previously untreated patients nested in a concurrent chemoradiation protocol were reviewed to correlate patterns of local‐regional tumor extent to distant metastasis. Biomarker assessment was: HPV in situ hybridization and epidermal growth factor receptor (EGFR) immunointensity. Results The 3‐year disease‐specific survival (DSS) for patients presenting with and without matted nodes was 69% and 94%, respectively ( p = .003). Matted nodes were a poor prognostic factor independent of T classification, HPV, EGFR, and smoking status. For patients who were HPV+, 7 of 11 died of distant metastasis and 6 of 7 with distant metastasis had matted nodes. Conclusion Matted nodes are a novel marker of poor prognosis in oropharyngeal SCC independent of established prognostic factors. Matted nodes may identify patients at risk for the development of distant metastasis who could benefit from systemic therapy, whereas patients without matted nodes may be candidates for de‐escalation of therapy. © 2012 Wiley Periodicals, Inc. Head Neck , 2012Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94456/1/21997_ftp.pd

    Pretreatment dietary intake is associated with tumor suppressor DNA methylation in head and neck squamous cell carcinomas

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    Diet is associated with cancer prognosis, including head and neck cancer (HNC), and has been hypothesized to influence epigenetic state by determining the availability of functional groups involved in the modification of DNA and histone proteins. The goal of this study was to describe the association between pretreatment diet and HNC tumor DNA methylation. Information on usual pretreatment food and nutrient intake was estimated via food frequency questionnaire (FFQ) on 49 HNC cases. Tumor DNA methylation patterns were assessed using the Illumina Goldengate Methylation Cancer Panel. First, a methylation score, the sum of individual hypermethylated tumor suppressor associated CpG sites, was calculated and associated with dietary intake of micronutrients involved in one-carbon metabolism and antioxidant activity, and food groups abundant in these nutrients. Second, gene specific analyses using linear modeling with empirical Bayesian variance estimation were conducted to identify if methylation at individual CpG sites was associated with diet. All models were controlled for age, sex, smoking, alcohol and HPV status. Individuals reporting in the highest quartile of folate, vitamin B12 and vitamin A intake, compared with those in the lowest quartile, showed significantly less tumor suppressor gene methylation, as did patients reporting the highest cruciferous vegetable intake. Gene specific analyses identified differential associations between DNA methylation and vitamin B12 and vitamin A intake when stratifying by HPV status. These preliminary results suggest that intake of folate, vitamin A and vitamin B12 may be associated with the tumor DNA methylation profile in HNC and enhance tumor suppression

    Prevalence and predictive role of p16 and epidermal growth factor receptor in surgically treated oropharyngeal and oral cavity cancer

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    Background The purpose of this study was to describe the relationship of p16 and epidermal growth factor receptor (EGFR) expression with survival in surgically treated patients who had oropharyngeal or oral cavity squamous cell carcinoma (SCC). Methods Tissue from 36 patients with oropharyngeal SCC and 49 patients with oral cavity SCC treated between 1997 and 2001 was imbedded and immunostained using a tissue microarray. Results The p16 was positive in 57% and 13% of patients with oropharyngeal SCC and oral cavity SCC, respectively. EGFR was positive in 60% and 63% of patients with oropharyngeal SCC and oral cavity SCC, respectively. In patients with oropharyngeal SCC, p16 expression was associated with improved disease‐specific survival (DSS), overall survival (OS), and time to recurrence (TTR) ( p < .01, < .01, and <.01, respectively). EGFR expression was associated with poorer DSS, OS, and TTR ( p < .01, = .01, and < .01, respectively). For oropharyngeal SCC, when examining both p16 and EGFR expression as combined biomarkers, high p16 expression coupled with low EGFR expression was associated with improved DSS ( p p16 = .01; p EGFR = .01). Patients with oral cavity SCC showed no association between biomarker and outcome. Conclusions For patients with oropharyngeal SCC, high p16 and low EGFR were associated with improved outcome, suggesting a predictive role in surgically treated patients. © 2012 Wiley Periodicals, Inc. Head Neck, 2013Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99017/1/23087_ftp.pd
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