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1.  The Macrophage A2b Adenosine Receptor Regulates Tissue Insulin Sensitivity 
PLoS ONE  2014;9(6):e98775.
High fat diet (HFD)-induced type 2 diabetes continues to be an epidemic with significant risk for various pathologies. Previously, we identified the A2b adenosine receptor (A2bAR), an established regulator of inflammation, as a regulator of HFD-induced insulin resistance. In particular, HFD was associated with vast upregulation of liver A2bAR in control mice, and while mice lacking this receptor showed augmented liver inflammation and tissue insulin resistance. As the A2bAR is expressed in different tissues, here, we provide the first lead to cellular mechanism by demonstrating that the receptor's influence on tissue insulin sensitivity is mediated via its expression in macrophages. This was shown using a newly generated transgenic mouse model expressing the A2bAR gene in the macrophage lineage on an otherwise A2bAR null background. Reinstatement of macrophage A2bAR expression in A2bAR null mice fed HFD restored insulin tolerance and tissue insulin signaling to the level of control mice. The molecular mechanism for this effect involves A2bAR-mediated changes in cyclic adenosine monophosphate in macrophages, reducing the expression and release of inflammatory cytokines, which downregulate insulin receptor-2. Thus, our results illustrate that macrophage A2bAR signaling is needed and sufficient for relaying the protective effect of the A2bAR against HFD-induced tissue inflammation and insulin resistance in mice.
PMCID: PMC4043770  PMID: 24892847
2.  Fatty Acid Synthase Polymorphisms, Tumor Expression, Body Mass Index, Prostate Cancer Risk, and Survival 
Journal of Clinical Oncology  2010;28(25):3958-3964.
Fatty acid synthase (FASN) regulates de novo lipogenesis, body weight, and tumor growth. We examined whether common germline single nucleotide polymorphisms (SNPs) in the FASN gene affect prostate cancer (PCa) risk or PCa-specific mortality and whether these effects vary by body mass index (BMI).
In a prospective nested case-control study of 1,331 white patients with PCa and 1,267 age-matched controls, we examined associations of five common SNPs within FASN (and 5 kb upstream/downstream, R2 > 0.8) with PCa incidence and, among patients, PCa-specific death and tested for an interaction with BMI. Survival analyses were repeated for tumor FASN expression (n = 909).
Four of the five SNPs were associated with lethal PCa. SNP rs1127678 was significantly related to higher BMI and interacted with BMI for both PCa risk (Pinteraction = .004) and PCa mortality (Pinteraction = .056). Among overweight men (BMI ≥ 25 kg/m2), but not leaner men, the homozygous variant allele carried a relative risk of advanced PCa of 2.49 (95% CI, 1.00 to 6.23) compared with lean men with the wild type. Overweight patients carrying the variant allele had a 2.04 (95% CI, 1.31 to 3.17) times higher risk of PCa mortality. Similarly, overweight patients with elevated tumor FASN expression had a 2.73 (95% CI, 1.05 to 7.08) times higher risk of lethal PCa (Pinteraction = .02).
FASN germline polymorphisms were significantly associated with risk of lethal PCa. Significant interactions of BMI with FASN polymorphisms and FASN tumor expression suggest FASN as a potential link between obesity and poor PCa outcome and raise the possibility that FASN inhibition could reduce PCa-specific mortality, particularly in overweight men.
PMCID: PMC2940394  PMID: 20679621
3.  Gleason Score and Lethal Prostate Cancer: Does 3 + 4 = 4 + 3? 
Journal of Clinical Oncology  2009;27(21):3459-3464.
Gleason grading is an important predictor of prostate cancer (PCa) outcomes. Studies using surrogate PCa end points suggest outcomes for Gleason score (GS) 7 cancers vary according to the predominance of pattern 4. These studies have influenced clinical practice, but it is unclear if rates of PCa mortality differ for 3 + 4 and 4 + 3 tumors. Using PCa mortality as the primary end point, we compared outcomes in Gleason 3 + 4 and 4 + 3 cancers, and the predictive ability of GS from a standardized review versus original scoring.
Patients and Methods
Three study pathologists conducted a blinded standardized review of 693 prostatectomy and 119 biopsy specimens to assign primary and secondary Gleason patterns. Tumor specimens were from PCa patients diagnosed between 1984 and 2004 from the Physicians' Health Study and Health Professionals Follow-Up Study. Lethal PCa (n = 53) was defined as development of bony metastases or PCa death. Hazard ratios (HR) were estimated according to original GS and standardized GS. We compared the discrimination of standardized and original grading with C-statistics from models of 10-year survival.
For prostatectomy specimens, 4 + 3 cancers were associated with a three-fold increase in lethal PCa compared with 3 + 4 cancers (95% CI, 1.1 to 8.6). The discrimination of models of standardized scores from prostatectomy (C-statistic, 0.86) and biopsy (C-statistic, 0.85) were improved compared to models of original scores (prostatectomy C-statistic, 0.82; biopsy C-statistic, 0.72).
Ignoring the predominance of Gleason pattern 4 in GS 7 cancers may conceal important prognostic information. A standardized review of GS can improve prediction of PCa survival.
PMCID: PMC2717753  PMID: 19433685
4.  Testing a Multigene Signature of Prostate Cancer Death in the Swedish Watchful Waiting Cohort 
While prostate cancer is a leading cause of cancer death, most men die with and not from their disease, underscoring the urgency to distinguish potentially lethal from indolent prostate cancer. We tested the prognostic value of a previously identified multigene signature of prostate cancer progression to predict cancer-specific death. The Örebro Watchful Waiting Cohort included 172 men with localized prostate cancer of whom 40 died of prostate cancer. We quantified protein expression of the markers in tumor tissue by immunohistochemistry, and stratified the cohort by quintiles according to risk classification. We accounted for clinical parameters (age, Gleason, nuclear grade, tumor volume) using Cox regression, and calculated Receiver Operator Curves to compare discriminatory ability. The hazard ratio of prostate cancer death increased with increasing risk classification by the multigene model, with a 16-fold greater risk comparing highest versus lowest risk strata, and predicted outcome independent of clinical factors (p=0.002). The best discrimination came from combining information from the multigene markers and clinical data, which perfectly classified the lowest risk stratum where no one developed lethal disease; using the two lowest risk groups as referent, the hazard ratio (95% confidence interval) was 11.3 (4.0–32.8) for the highest risk group and difference in mortality at 15 years was 60% (50–70%). The combined model provided greater discriminatory ability (AUC 0.78) than the clinical model alone (AUC 0.71), p=0.04. Molecular tumor markers can add to clinical parameters to help distinguish lethal and indolent prostate cancer, and hold promise to guide treatment decisions.
PMCID: PMC2536630  PMID: 18583469

Results 1-4 (4)