Citations

Abstract High-risk susceptibility genes explain <40% of the excess risk of familial ovarian cancer. Therefore, other ovarian cancer susceptibility genes are likely to exist. We have used a single nucleotide polymorphism (SNP)–tagging approach to evaluate common variants in 13 genes involved in cell cycle control—CCND1, CCND2, CCND3, CCNE1, CDK2, CDK4, CDK6, CDKN1A, CDKN1B, CDKN2A, CDKN2B, CDKN2C, and CDKN2D—and risk of invasive epithelial ovarian cancer. We used a two-stage, multicenter, case-control study. In stage 1, 88 SNPs that tag common variation in these genes were genotyped in three studies from the United Kingdom, United States, and Denmark (∼1,500 cases and 2,500 controls). Genotype frequencies in cases and controls were compared using logistic regression. In stage 2, eight other studies from Australia, Poland, and the United States (∼2,000 cases and ∼3,200 controls) were genotyped for the five most significant SNPs from stage 1. No SNP was significant in the stage 2 data alone. Using the combined stages 1 and 2 data set, CDKN2A rs3731257 and CDKN1B rs2066827 were associated with disease risk (unadjusted P trend = 0.008 and 0.036, respectively), but these were not significant after adjusting for multiple testing. Carrying the minor allele of these SNPs was found to be associated with reduced risk [OR, 0.91 (0.85–0.98) for rs3731257; and OR, 0.93 (0.87–0.995) for rs2066827]. In conclusion, we have found evidence that a single tagged SNP in both the CDKN2A and CDKN1B genes may be associated with reduced ovarian cancer risk. This study highlights the need for multicenter collaborations for genetic association studies. [Cancer Res 2007;67(7):3027–35]

The peripheral nerve of experimental diabetic neuropathy (EDN) is reported to be ischemic and hypoxic, with an increased dependence on anaerobic metabolism, requiring increased energy substrate stores. When glucose stores become reduced, fiber degeneration has been reported. We evaluated glucose uptake, nerve energy metabolism, the polyol pathway, and protein kinase C (PKC) activity in EDN induced by streptozotocin. Control and diabetic rats received lipoic acid (0, 10, 25, 50, 100 mg/kg). Duration of diabetes was 1 month, and alpha-lipoic acid was administered intraperitoneally 5 times per week for the final week of the experiment. Nerve glucose uptake was reduced to 60, s 37, and 30% of control values in the sciatic nerve, L5 dorsal root ganglion, and superior cervical ganglion (SCG), respectively, in rats with EDN. Alpha-lipoic acid supplementation had no effect on glucose uptake in normal nerves at any dose, but reversed the deficit in EDN, with a threshold between 10 and 25 mg/kg. Endoneurial glucose, fructose, sorbitol, and myo-inositol were measured in sciatic nerve. Alpha-lipoic acid had no significant effect on either energy metabolism or polyol pathway of normal nerves. In EDN, endoneurial glucose, fructose, and sorbitol were significantly increased, while myo-inositol was significantly reduced. Alpha-lipoic acid had a biphasic effect: it dose-dependently increased fructose, glucose, and sorbitol, peaking at 25 mg/kg, and then fell beyond that dose, and it dose-dependently increased myo-inositol. Sciatic nerve cytosolic PKC was increased in EDN. ATP, creatine phosphate, and lactate were measured in sciatic nerve and SCG. Alpha-lipoic acid prevented the reduction in SCG creatine phosphate. We conclude that glucose uptake is reduced in EDN and that this deficit is dose-dependently reversed by alpha-lipoic acid, a change associated with an improvement in peripheral nerve function.

Little information is available regarding the optimal timing of exercise in insulin-dependent diabetes mellitus (IDDM) patients. In this study, six IDDM patients receiving ultralente-based intensive insulin therapy were studied during 30 min of exercise (∼60% Vo2max), before breakfast, and at 1600. On two other occasions, they were studied at rest. Plasma glucose increased from 6.7 ± 0.4 to 9.1 ± 0.4 mM during morning exercise (P < 0.01). In contrast, mean plasma glucose did not change during afternoon exercise (≸ = 0.3 ± 0.5 mM, NS); however, there was a 0.3- to 1.0-mM decrease in three subjects. The observed difference in the glycemic response to exercise could not be explained on the basis of changes in plasma glucagon, growth hormone, norepinephrine, or epinephrine. Plasma cortisol was higher (P < 0.02) in the morning than in the afternoon, and plasma free-insulin concentrations were lower (P < 0.05). These data indicate that the risk of exerciseinduced hypoglycemia is lowest before breakfast. The reason for the divergent glycemic responses to exercise is not entirely clear but may be related to the observed differences in free-insulin concentrations. Because of the lower risk of hypoglycemia, our results suggest prebreakfast exercise may be preferable for some IDDM patients receiving intensive insulin therapy. Whether these findings are relevant to patients receiving other types of insulin therapy will require further investigation.

AbstractWaldenström macroglobulinemia (WM) is an incurable lymphoplasmacytic lymphoma with limited options of therapy. Protein kinase Cβ (PKCβ) regulates cell survival and growth in many B-cell malignancies. In this study, we demonstrate up-regulation of PKCβ protein in WM using protein array techniques and immunohistochemistry. Enzastaurin, a PKCβ inhibitor, blocked PKCβ activity and induced a significant decrease of proliferation at 48 hours in WM cell lines (IC50, 2.5-10 μM). Similar effects were demonstrated in primary CD19+ WM cells, without cytotoxicity on peripheral blood mononuclear cells. In addition, enzastaurin overcame tumor cell growth induced by coculture of WM cells with bone marrow stromal cells. Enzastaurin induced dose-dependent apoptosis at 48 hours mediated via induction of caspase-3, caspase-8, caspase-9, and PARP cleavage. Enzastaurin inhibited Akt phosphorylation and Akt kinase activity, as well as downstream p-MARCKS and ribosomal p-S6. Furthermore, enzastaurin demonstrated additive cytotoxicity in combination with bortezomib, and synergistic cytotoxicity in combination with fludarabine. Finally, in an in vivo xenograft model of human WM, significant inhibition of tumor growth was observed in the enzastaurin-treated mice (P = .028). Our studies therefore show that enzastaurin has significant antitumor activity in WM both in vitro and in vivo, providing the framework for clinical trials to improve patient outcome in WM.

Abstract Rationale Treatment and prognoses of diffuse parenchymal lung diseases (DPLDs) varies by diagnosis. Obtaining a uniform diagnosis among observers is difficult. Objectives Evaluate diagnostic agreement between academic and community-based physicians for patients with DPLDs, and determine if an interactive approach between clinicians, radiologists, and pathologists improved diagnostic agreement in community and academic centers. Methods Retrospective review of 39 patients with DPLD. A total of 19 participants reviewed cases at 2 community locations and 1 academic location. Information from the history, physical examination, pulmonary function testing, high-resolution computed tomography, and surgical lung biopsy was collected. Data were presented in the same sequential fashion to three groups of physicians on separate days. Measurements and Main Results Each observer's diagnosis was coded into one of eight categories. A κ statistic allowing for multiple raters was used to assess agreement in diagnosis. Interactions between clinicians, radiologists, and pathologists improved interobserver agreement at both community and academic sites; however, final agreement was better within academic centers (κ = 0.55–0.71) than within community centers (κ = 0.32–0.44). Clinically significant disagreement was present between academic and community-based physicians (κ = 0.11–0.56). Community physicians were more likely to assign a final diagnosis of idiopathic pulmonary fibrosis compared with academic physicians. Conclusions Significant disagreement exists in the diagnosis of DPLD between physicians based in communities compared with those in academic centers. Wherever possible, patients should be referred to centers with expertise in diffuse parenchymal lung disorders to help clarify the diagnosis and provide suggestions regarding treatment options.

Abstract Innovations and Challenges in Renal Cancer, chaired by Michael B. Atkins, was held April 28 to 29, 2006 in Cambridge, Massachusetts. The conference brought together leading experts in the fields of cancer research, medical oncology, urology, immunology, radiology, and immunotherapy, with the goal of advancing the field of renal cancer treatment by critiquing new data from ongoing clinical trials and stimulating communication among those involved in basic and clinical research. The conference proceedings published in this educational supplement to Clinical Cancer Research are intended to provide timely information and recommendations on important aspects of renal cancer genetics and biology and advances in prognostic classification and treatment.

Intermittent claudication is the most common symptom of peripheral arterial disease (PAD), in part due to an inadequate rise in limb blood flow with exercise. Claudication causes a severe impairment in functional capacity and quality of life in over 3 million Americans. Basic fibroblast growth factor (bFGF) stimulates angiogenesis in vivo and improves limb blood flow in several animal models of hindlimb ischemia. However, the relative safety and efficacy of angiogenic molecules in the treatment of claudication has not been fully evaluated in prospective, blinded clinical trials. In this study, a randomized, double-blind, placebo-controlled, phase II trial of recombinant human bFGF for the treatment of intermittent claudication was performed. bFGF was administered weekly by intravenous infusions of 2 μg/kg for 6 sequential weeks (total dose 12 μg/kg). The primary efficacy endpoint was change in peak walking time (PWT) on a graded exercise treadmill protocol. Secondary efficacy endpoints included changes in functional status as measured by validated questionnaires. The study was stopped prematurely after treatment of the first 24 subjects due to proteinuria in five of the 16 subjects who received systemic bFGF, which exceeded 1000 mg/24 h in four of these five subjects. The small sample size limited evaluation of the predefined efficacy endpoints; however, there was no significant difference between the treatment and control groups for any of the measures of efficacy. In conclusion, intravenous administration of bFGF delivered at low doses weekly for 6 weeks was associated with a high rate of severe proteinuria. It is speculated that bFGF-related proteinuria in this study was primarily related to the systemic route of administration and the frequent dosing schedule. Future clinical trials of bFGF protein should carefully monitor renal function and consider alternative dosing schedules and drug administration routes.