Citations

Abstract The role of metformin in prostate cancer chemoprevention remains unclear. REDUCE, which followed biopsy-negative men with protocol-dictated PSA-independent biopsies at 2- and 4-years, provides an opportunity to evaluate the link between metformin use and prostate cancer diagnosis with minimal confounding from screening biases. In diabetic men from REDUCE, we tested the association between metformin use, use of other antidiabetic medications, versus no antidiabetic medication use, and prostate cancer diagnosis as well as prostate cancer grade (low-grade Gleason 4–6 and high-grade Gleason 7–10) using logistic regression. Of the 540 diabetic men with complete data, 205 (38%) did not report use of any antidiabetic medications, 141 (26%) reported use of at least one antidiabetic medication other than metformin, and 194 (36%) reported use of metformin. During the 4-year study, 122 men (23%) were diagnosed with prostate cancer. After adjusting for various clinical and demographic characteristics, we found that metformin use was not significantly associated with total (OR, 1.19; P = 0.50), low- (OR, 1.01; P = 0.96), or high-grade (OR, 1.83; P = 0.19) prostate cancer diagnosis. Likewise, there was no significant association between the use of non-metformin antidiabetic medications and prostate cancer risk in both crude (OR, 1.02; P = 0.95) and multivariable analysis (OR, 0.85; P = 0.56). Furthermore, the interactions between antidiabetic medication use and BMI, geographic location, coronary artery disease, smoking, and treatment group were not significant (all P > 0.05). Among diabetic men with a negative prestudy biopsy who all underwent biopsies largely independent of PSA, metformin use was not associated with reduced risk of prostate cancer diagnosis. Cancer Prev Res; 8(11); 1055–60. ©2015 AACR.

Abstract Purpose: A recent meta-analysis showed that aspirin was associated with reduced prostate cancer risk. As anti-inflammatory medications lower PSA levels, whether these findings reflect reduced prostate cancer detection or lower prostate cancer risk is unknown. We tested the association between aspirin and nonaspirin NSAID use on prostate cancer diagnosis in REDUCE, where all men received biopsies at 2 and 4 years largely independent of PSA. REDUCE tested dutasteride for prostate cancer risk reduction in men with a PSA of 2.5 to 10.0 ng/mL and a negative prestudy biopsy. Experimental Design: We examined the association between aspirin, NSAIDs, or both and total, low-grade (Gleason < 7), or high-grade (Gleason ≥ 7) prostate cancer versus no prostate cancer using multinomial logistic regression among 6,390 men who underwent ≥1 on-study biopsy. Multivariable analyses were adjusted for age, race, geographic region, PSA, prostate volume, digital rectal examination, body mass index, treatment arm, smoking, alcohol, statins, hypertension, diabetes, and cardiovascular disease. Results: Overall, 3,169 men (50%) were nonusers, 1,368 (21%) used aspirin, 1,176 (18%) used NSAIDs, and 677 (11%) used both. In unadjusted models, aspirin was associated with reduced prostate cancer risk (OR = 0.85, P = 0.036). In multivariable analyses, aspirin was associated with reduced total prostate cancer risk (OR = 0.81, P = 0.015). Use of NSAIDs or NSAIDs and aspirin was not associated with total, low-grade, or high-grade prostate cancer, though all ORs were <1 (all P ≥ 0.08). Therefore, we created a dichotomous variable of aspirin and/or NSAID users versus nonusers. On multivariable analysis, the use of aspirin and/or NSAIDs was significantly associated with decreased total (OR = 0.87, P = 0.030) and high-grade (OR = 0.80, P = 0.040), but not with low-grade, prostate cancer risk (OR = 0.90, P = 0.15). Results were similar in placebo and dutasteride arms. Conclusions: Among men with a negative biopsy, aspirin and/or NSAID use was associated with decreased prostate cancer risk. Additional studies are warranted. Clin Cancer Res; 21(4); 756–62. ©2014 AACR.

Abstract Background: Studies suggest that obesity is associated with lower risk of prostate cancer but more aggressive cancers. As obesity lowers PSA levels, these observations may be influenced by detection bias. We examined the association between obesity and risk of low- and high-grade prostate cancer in REDUCE, in which biopsies were largely independent of PSA. Methods: The REDUCE study tested dutasteride for prostate cancer risk reduction in men with a PSA of 2.5 to 10.0 ng/mL and a negative biopsy. Study participants included 6,729 men who underwent at least one on-study biopsy. The association between baseline body mass index (BMI <25 kg/m2 normal weight; 25–29.9 kg/m2 overweight; and ≥30 kg/m2 obese) and risk of high-grade (Gleason ≥7) or low-grade prostate cancer (Gleason <7) versus no prostate cancer was examined using multinomial logistic regression. Results: Overall, 1,739 men (27%) were normal weight, 3,384 (53%) overweight, and 1,304 (20%) were obese. Obesity was associated with lower risk of low-grade prostate cancer in both univariable (OR, 0.74; P = 0.001) and multivariable analyses (OR, 0.79; P = 0.01). In univariable analysis, obesity was not associated with high-grade prostate cancer (OR, 1.08; P = 0.50). However, in multivariable analysis, obesity was associated with increased risk of high-grade prostate cancer (OR, 1.28; P = 0.042). This analysis was not able to address how obesity may influence prostate cancer progression. Conclusions: Obesity is associated with decreased risk of low-grade and increased risk of high-grade prostate cancer. These data provide further support to the hypothesis that obesity is associated with aggressive prostate cancer. Impact: Obesity is linked with aggressive prostate cancer. Avoiding obesity may prevent the risk of developing high-grade prostate cancer. Cancer Epidemiol Biomarkers Prev; 23(12); 2936–42. ©2014 AACR.

Abstract Oncolytic viruses can exert their antitumor activity via direct oncolysis or activation of antitumor immunity. Although reovirus is currently under clinical investigation for the treatment of localized or disseminated cancer, any potential immune contribution to its efficacy has not been addressed. This is the first study to investigate the ability of reovirus to activate human dendritic cells (DC), key regulators of both innate and adaptive immune responses. Reovirus induced DC maturation and stimulated the production of the proinflammatory cytokines IFN-α, TNF-α, IL-12p70, and IL-6. Activation of DC by reovirus was not dependent on viral replication, while cytokine production (but not phenotypic maturation) was inhibited by blockade of PKR and NF-κB signaling. Upon coculture with autologous NK cells, reovirus-activated DC up-regulated IFN-γ production and increased NK cytolytic activity. Moreover, short-term coculture of reovirus-activated DC with autologous T cells also enhanced T cell cytokine secretion (IL-2 and IFN-γ) and induced non-Ag restricted tumor cell killing. These data demonstrate for the first time that reovirus directly activates human DC and that reovirus-activated DC stimulate innate killing by not only NK cells, but also T cells, suggesting a novel potential role for T cells in oncolytic virus-induced local tumor cell death. Hence reovirus recognition by DC may trigger innate effector mechanisms to complement the virus’s direct cytotoxicity, potentially enhancing the efficacy of reovirus as a therapeutic agent.

Abstract The American Joint Committee on Cancer/Union Internationale Contre le Cancer ( AJCC / UICC ) TNM staging system provides the most reliable guidelines for the routine prognostication and treatment of colorectal carcinoma. This traditional tumour staging summarizes data on tumour burden (T), the presence of cancer cells in draining and regional lymph nodes (N) and evidence for distant metastases (M). However, it is now recognized that the clinical outcome can vary significantly among patients within the same stage. The current classification provides limited prognostic information and does not predict response to therapy. Multiple ways to classify cancer and to distinguish different subtypes of colorectal cancer have been proposed, including morphology, cell origin, molecular pathways, mutation status and gene expression‐based stratification. These parameters rely on tumour‐cell characteristics. Extensive literature has investigated the host immune response against cancer and demonstrated the prognostic impact of the in situ immune cell infiltrate in tumours. A methodology named ‘Immunoscore’ has been defined to quantify the in situ immune infiltrate. In colorectal cancer, the Immunoscore may add to the significance of the current AJCC / UICC TNM classification, since it has been demonstrated to be a prognostic factor superior to the AJCC / UICC TNM classification. An international consortium has been initiated to validate and promote the Immunoscore in routine clinical settings. The results of this international consortium may result in the implementation of the Immunoscore as a new component for the classification of cancer, designated TNM ‐I ( TNM ‐Immune). © 2013 The Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Genetic College Many genomic elements in humans are associated with behavior, including educational attainment. In a genome-wide association study including more than 100,000 samples, Rietveld et al. (p. 1467 , published online 30 May; see the Perspective by Flint and Munafò ) looked for genes related to educational attainment in Caucasians. Small genetic effects at three loci appeared to impact educational attainment.

Vascular endothelial growth factor (VEGF) acts primarily as an endothelial cell mitogen via the specific receptors Flk-1 and Flt-1. To help further define the possible role of VEGF in the control of pituitary cell function, we examined Flk-1 expression in normal rat pituitaries and in GH3 cells. Flk-1 expression was studied by immunohistochemistry, in situ hybridization, and double-labeling immunofluorescence combined with confocal laser microscopy. In normal rat pituitaries, Flk-1-immunoreactive cells appeared widely distributed only in the anterior lobe and were not detected in the intermediate or posterior lobe. Apart from the adenohypophysial cells, Flk-1 immunopositivity was also evident in endothelial cells of many capillaries distributed throughout the gland. Immunohistochemistry also showed that majority of GH3 cells expressed Flk-1 protein. In situ hybridization showed conclusive staining with the antisense probe and confirmed the immunohistochemical results. The double immunofluorescence method revealed Flk-1 expression in all types of hormone-producing adenohypophysial cells but not in folliculostellate cells. The percentage of immunopositive cells varied among the various cell types. The present study demonstrates that pituitary cells are not only sources of VEGF but also targets of this multifunctional substance, supporting the concept that VEGF functions as an autocrine/paracrine factor in the pituitary.