Citations

Abstract SR13668, an orally active Akt pathway inhibitor, has demonstrated cancer chemopreventive potential in preclinical studies. To accelerate the clinical development of this promising agent, we designed and conducted the first-ever phase 0 chemoprevention trial to evaluate and compare the effects of food and formulation on SR13668 bioavailability. Healthy adult volunteers were randomly assigned to receive a single, 38-mg oral dose of SR13668 in one of five different formulations, with or without food. On the basis of existing animal data, SR13668 in a PEG400/Labrasol oral solution was defined as the reference formulation. Blood samples were obtained pre- and post-agent administration for pharmacokinetic analyses. Area under the plasma concentration–time curve (AUC0–∞) was defined as the primary endpoint. Data were analyzed and compared using established statistical methods for phase 0 trials with a limited sample size. Participants (n = 20) were rapidly accrued over a 5-month period. Complete pharmacokinetic data were available for 18 randomized participants. AUC0–∞ values were highest in the fed state (range = 122–439 ng/mL × hours) and were statistically significantly different across formulations (P = 0.007), with Solutol HS15 providing the highest bioavailability. SR13668 time to peak plasma concentration (3 hours; range, 2–6 hours) and half-life were (11.2 ± 3.1 hours) were not formulation-dependent. Using a novel, highly efficient study design, we rapidly identified a lead formulation of SR13668 for further clinical testing. Our findings support application of the phase 0 trial paradigm to accelerate chemoprevention agent development. Cancer Prev Res; 4(3); 347–53. ©2011 AACR.

AbstractPurposeWe assessed risk factors for splenic injury during colectomy and associated outcomes for a 15‐year period at a single institution.MethodsAll adult general surgery patients who sustained a splenic injury during colectomy at our institution from 1992 to 2007 were retrospectively identified and matched 1:1 to controls without splenic injury. Putative risk factors were assessed using paired univariate analysis and conditional logistic regression. Differences in short‐ and long‐term mortality were assessed using the log‐rank test. Results are reported as a proportion, median, or odds ratio [OR (95% confidence intervals)].ResultsA total of 118 patients were included: 59 patients with splenic injury and 59 control patients. Statistically significant risk factors for splenic injury during colectomy found on univariate analysis included: splenic flexure mobilization, OR 21.00 (2.82–156.12); Charlson comorbidity index ≥5, OR 3.17 (1.26–7.93); ASA class ≥3, OR 5.33 (1.55–18.3); and nonelective surgery, OR 5.00 (1.1–22.82). On multivariate analysis, only splenic flexure mobilization was independently associated with increased risk of splenic injury (OR 18.4 (2.1–161); p = 0.0085). Splenic injured patients trended toward decrease survival both at 30 days (98 vs. 88%; p = 0.06) and at 5 years (58 vs. 55%), with a hazard ratio of 1.6 (1.0, 2.6; p = 0.05).ConclusionsSplenic flexure mobilization is the primary risk factor for splenic injury during colectomy, independent of other factors, such as higher ASA class, Charlson score, and nonelective surgery. Splenic injury during colectomy has an increased risk of death in both the short‐ and long‐term.

Abstract Purpose: SR13668, an orally active AKT pathway inhibitor, has demonstrated cancer chemopreventive potential in preclinical studies. To accelerate the clinical development of this promising agent, we designed and conducted the first-ever phase 0 chemoprevention trial to evaluate and compare the effects of food and formulation on SR13668 bioavailability. Patients and Methods: Healthy adult volunteers were randomly assigned to receive a single 38-mg oral dose of SR13668 in one of five different formulations, with or without food. Based on existing animal data, SR13668 in a PEG400/Labrasol@ oral solution (formulation 1) was defined as the reference formulation. Four self-emulsifying solid dispersion test formulations in capsules were also investigated: Solutol@ HS 15 (formulation 2), Solutol@ HS 15/Vitamin E TGPS (50/50 w/w %) (formulation 3), Vitamin E TGPS (formulation 4), and Myrj 53 (formulation 5). SR163668 bioavailability was compared using a two-stage study design. In stage I, participants were randomized to receive the formulation 1 with or without a high-fat meal after an overnight fast. In Stage II, participants were randomly assigned to receive the test formulations, using the preferred dietary condition identified in stage I. Blood samples were obtained pre- and post-agent administration for pharmacokinetic analyses. Area under the plasma concentration-time curve (AUC) was defined as the primary endpoint. Data were analyzed and compared using established statistical methods for phase 0 trials with a limited sample size. Results: Participants (N=20) were rapidly accrued over a 5-month period. Complete pharmacokinetic data were available for 18 randomized participants. The time to peak plasma concentration and half-life values for SR13668 were 3 hours (range, 2 — 6 hours) and 11.2 ± 3.1 hours, respectively, and were not dependent on the formulation. In stage I, the oral bioavailability of SR13668 in formulation 1 was greater under the fed versus fasting dietary state (p = 0.05, Wilcoxon rank-sum test). Therefore, the fed state was selected as the preferred dietary condition for stage II. In stage II, the bioavailability of SR13668 for each of the test formulations were compared with the bioavailability of formulation 1 in the fed state. While not significantly different from formulation 1, formulation 2 AUC0-24h was significantly different (p = 0.004, ANOVA) from formulation 3, 4, and 5 (AUC0-24h, formulation 1- 222 ± 53 ng/ml·hr; AUC0-24h, formulation 2 — 302 ± 78 ng/ml·hr; AUC-177±39ng/ml·hr; AUC-144±29 0-24h, formulation30-24h, formulation 4 ng/ml·hr; AUC0-24h, formulation 5- 98 ± 21 ng/ml·hr). Formulation 1 AUC0-24h was almost 40% lower than the value achieved with formulation 2, and not significantly different from formulation 3, 4, and 5. Thus, formulation 2 provided the highest bioavailability of SR13668. Conclusions: Using a novel, highly efficient study design, we rapidly identified a lead formulation (Solutol@ HS 15) of SR13668 for further clinical testing. Our findings support application of the phase 0 trial paradigm to accelerate chemoprevention agent development. Supported by NIH grants N01-CN-35000, CA15083-34C3 and UL1 RR024150. Citation Information: Cancer Prev Res 2010;3(12 Suppl):CN02-03.

Purpose Hand-foot syndrome (HFS) is a dose-limiting toxicity of capecitabine for which no effective preventative treatment has been definitively demonstrated. This trial was conducted on the basis of preliminary data that a urea/lactic acid–based topical keratolytic agent (ULABTKA) may prevent HFS. Patients and Methods A randomized, double-blind phase III trial evaluated 137 patients receiving their first ever cycle of capecitabine at a dose of either 2,000 or 2,500 mg/m2 per day for 14 days. Patients were randomly assigned to a ULABTKA versus a placebo cream, which was applied to the hands and feet twice per day for 21 days after the start of capecitabine. Patients completed an HFS diary (HFSD) daily. HFS toxicity grade (Common Terminology Criteria for Adverse Events [CTCAE] v3.0) was also collected at baseline and at the end of each cycle. The primary end point was the incidence of moderate/severe HFS symptoms in the first treatment cycle, based on the patient-reported HFSD. Results The percentage of patients with moderate/severe HFS symptoms was not different between groups, being 13.6% in the ULABTKA arm and 10.2% in the placebo arm (P = .768 by Fisher's exact test). The odds ratio was 1.37 (95% CI, 0.37 to 5.76). Cycle 1 CTCAE skin toxicity was higher in the ULABTKA arm but not significantly so (33% v 27%; P = .82). No significant differences were observed in other toxicities between groups. Conclusion These data do not support the efficacy of a ULABTKA cream for preventing HFS symptoms in patients receiving capecitabine.

Purpose Hot flashes are a common problem for which effective and safe treatments are needed. The current trial was conducted on the basis of preliminary promising data that pregabalin decreased hot flashes. Patients and Methods A double-blind, placebo-controlled, randomized trial design was used to compare pregabalin at target doses of 75 mg twice daily and 150 mg twice daily with a placebo. Hot flash frequencies and scores (frequency times mean severity) were recorded daily during a baseline week and for six treatment weeks. The primary end point for this study was the change-from-baseline hot flash score during treatment week 6 between the 150 mg twice daily target pregabalin treatment and placebo. Nonparametric Wilcoxon rank sum tests, two-sample t tests, and χ 2 tests were used to compare the primary and secondary hot flash efficacy end points between pregabalin treatments and placebo. Results Hot flash score changes available for 163 patients during the sixth treatment week compared with a baseline week decreased by 50%, 65%, and 71% in the placebo, and target 75 mg twice daily and 150 mg twice daily pregabalin arms, respectively (P = .009 and P = .007, comparing respective pregabalin arms to the placebo arm). While some toxicities were significantly more common in the pregabalin arms, being more evident with the higher dose, pregabalin was generally well tolerated by most patients. Conclusion Pregabalin decreases hot flashes and is reasonably well tolerated. A target dose of 75 mg twice daily is recommended. Its effects appear to be roughly comparable to what has been reported with gabapentin and with some newer antidepressants.

AbstractMotivation: A central problem in biomarker discovery from large-scale gene expression or single nucleotide polymorphism (SNP) data is the computational challenge of taking into account the dependence among all the features. Methods that ignore the dependence usually identify non-reproducible biomarkers across independent datasets. We introduce a new graph-based semi-supervised feature classification algorithm to identify discriminative disease markers by learning on bipartite graphs. Our algorithm directly classifies the feature nodes in a bipartite graph as positive, negative or neutral with network propagation to capture the dependence among both samples and features (clinical and genetic variables) by exploring bi-cluster structures in a graph. Two features of our algorithm are: (1) our algorithm can find a global optimal labeling to capture the dependence among all the features and thus, generates highly reproducible results across independent microarray or other high-thoughput datasets, (2) our algorithm is capable of handling hundreds of thousands of features and thus, is particularly useful for biomarker identification from high-throughput gene expression and SNP data. In addition, although designed for classifying features, our algorithm can also simultaneously classify test samples for disease prognosis/diagnosis.Results: We applied the network propagation algorithm to study three large-scale breast cancer datasets. Our algorithm achieved competitive classification performance compared with SVMs and other baseline methods, and identified several markers with clinical or biological relevance with the disease. More importantly, our algorithm also identified highly reproducible marker genes and enriched functions from the independent datasets.Availability: Supplementary results and source code are available at http://compbio.cs.umn.edu/Feature_Class.Contact: kuang@cs.umn.eduSupplementary information: Supplementary data are available at Bioinformatics online.

Acetylation of histone H3 lysine 56 (H3-K56) occurs in S phase, and cells lacking H3-K56 acetylation are sensitive to DNA-damaging agents. However, the histone acetyltransferase (HAT) that catalyzes global H3-K56 acetylation has not been found. Here we show that regulation of Ty1 transposition gene product 109 (Rtt109) is an H3-K56 HAT. Cells lacking Rtt109 or expressing rtt109 mutants with alterations at a conserved aspartate residue lose H3-K56 acetylation and exhibit increased sensitivity toward genotoxic agents, as well as elevated levels of spontaneous chromosome breaks. Thus, Rtt109, which shares no sequence homology with any other known HATs, is a unique HAT that acetylates H3-K56.