Quercetin enhances 5-fluorouracil-induced apoptosis in MSI colorectal cancer cells through p53 modulation

Purpose: Colorectal tumors (CRC) with microsatellite instability (MSI) show resistance to chemotherapy with 5-fluorouracil (5-FU), the most widely used pharmacological drug for CRC treatment. The aims of this study were to test the ability of quercetin (Q) and luteolin (L) to increase sensitivity of MSI CRC cells to 5-FU and characterize the dependence of the effects on cells´ p53 status. Methods: Two MSI human CRC derived cell lines were used, CO115 wild-type (wt) for p53 and HCT15 that harbors a p53 mutation. Apoptosis induction in these cells by 5-FU, Q and L alone and in combinations were evaluated by TUNEL and western. The dependence on p53 of the effects was confirmed by small interference RNA (siRNA) in CO115 cells and in MSI HCT116 wt and p53 knockout cells. Results: CO115 p53-wt cells are more sensitive to 5-FU than the p53 mutated HCT15. The combination treatment of 5-FU with L and Q increased apoptosis with a significant effect for Q in CO115. Both flavonoids increased p53 expression in both cell lines, an effect particularly remarkable for Q. The significant apoptotic enhancement in CO115 incubated with Q plus 5-FU involved the activation of the apoptotic mitochondrial pathway. Importantly, knockdown of p53 by siRNA in CO115 cells and p53 knockout in HCT116 cells totally abrogated apoptosis induction, demonstrating the dependence of the effect on p53 modulation by Q. Conclusion: This study suggests the potential applicability of these phytochemicals for enhancement 5-FU efficiency in MSI CRC therapy, especially Q in p53 wt tumors.CPRX was supported by the Foundation for Science and Technology (FCT), Portugal, through the grant SFRH/BD/27524/2006 and the work was supported by the FCT research grant PTDC/AGR-AAM/70418/2006

Observational analytic studies in multiple sclerosis: controlling bias through study design and conduct. The Australian Multicentre Study of Environment and Immune Function

Rising multiple sclerosis incidence over the last 50 years and geographic patterns of occurrence suggest an environmental role in the causation of this multifactorial disease. Design options for epidemiological studies of environmental causes of multiple sclerosis are limited by the low incidence of the disease, possible diagnostic delay and budgetary constraints. We describe scientific and methodological issues considered in the development of the Australian Multicentre Study of Environment and Immune Function (the Ausimmune Study), which seeks, in particular, to better understand the causes of the well-known MS positive latitudinal gradient. A multicentre, case-control design down the eastern seaboard of Australia allows the recruitment of sufficient cases for adequate study power and provides data on environmental exposures that vary by latitude. Cases are persons with an incident first demyelinating event (rather than prevalent multiple sclerosis), sourced from a population base using a two tier notification system. Controls, matched on sex, age (within two years) and region of residence, are recruited from the general population. Biases common in case-control studies, eg, prevalence-incidence bias, admission-rate bias, non-respondent bias, observer bias and recall bias, as well as confounding have been carefully considered in the study design and conduct of the Ausimmune Study

Change & Maintaining Change in School Cafeterias: Economic and Behavioral-Economic Approaches to Increasing Fruit and Vegetable Consumption

Developing a daily habit of consuming fruits and vegetables (FV) in children is an important public-health goal. Eating habits acquired in childhood are predictive of adolescent and adult dietary patterns. Thus, healthy eating patterns developed early in life can protect the individual against a number of costly health deficits and may reduce the prevalence of obesity. At present, children in the United States (US) under-consume FV despite having access to them through the National School Lunch Program. Because access is an obstacle to developing healthy eating habits, particularly in low-income households, targeting children’s FV consumption in schools has the advantage of near-universal FV availability among more than 30 million US children. This chapter reviews economic and behavioral-economic approaches to increasing FV consumption in schools. Inclusion criteria include objective measurement of FV consumption (e.g., plate waste measures) and minimal demand characteristics. Simple but effective interventions include (a) increasing the variety of vegetables served, (b) serving sliced instead of whole fruits, (c) scheduling lunch after recess, and (d) giving children at least 25 minutes to eat. Improving the taste of FV and short-term incentivizing consumption of gradually increasing amounts can produce large increases in consumption of these foods. Low-cost game-based incentive program may increase the practicality of the latter strategy

Safety and efficacy of pioglitazone for the delay of cognitive impairment in people at risk of Alzheimer's disease (TOMMORROW): a prognostic biomarker study and a phase 3, randomised, double-blind, placebo-controlled trial

Background: The identification of people at risk of cognitive impairment is essential for improving recruitment in secondary prevention trials of Alzheimer's disease. We aimed to test and qualify a biomarker risk assignment algorithm (BRAA) to identify participants at risk of developing mild cognitive impairment due to Alzheimer's disease within 5 years, and to evaluate the safety and efficacy of low-dose pioglitazone to delay onset of mild cognitive impairment in these at-risk participants. Methods: In this phase 3, multicentre, randomised, double-blind, placebo-controlled, parallel-group study, we enrolled cognitively healthy, community living participants aged 65–83 years from 57 academic affiliated and private research clinics in Australia, Germany, Switzerland, the UK, and the USA. By use of the BRAA, participants were grouped as high risk or low risk. Participants at high risk were randomly assigned 1:1 to receive oral pioglitazone (0·8 mg/day sustained release) or placebo, and all low-risk participants received placebo. Study investigators, site staff, sponsor personnel, and study participants were masked to genotype, risk assignment, and treatment assignment. The planned study duration was the time to accumulate 202 events of mild cognitive impairment due to Alzheimer's disease in White participants who were at high risk (the population on whom the genetic analyses that informed the BRAA development was done). Primary endpoints were time-to-event comparisons between participants at high risk and low risk given placebo (for the BRAA objective), and between participants at high risk given pioglitazone or placebo (for the efficacy objective). The primary analysis included all participants who were randomly assigned, received at least one dose of study drug, and had at least one valid post-baseline visit, with significance set at p=0·01. The safety analysis included all participants who were randomly assigned and received at least one dose of study medication. An efficacy futility analysis was planned for when approximately 33% of the anticipated events occurred in the high-risk, White, non-Hispanic or Latino group. This trial is registered with ClinicalTrials.gov, NCT01931566. Findings: Between Aug 28, 2013, and Dec 21, 2015, we enrolled 3494 participants (3061 at high risk and 433 at low risk). Of those participants, 1545 were randomly assigned to pioglitazone and 1516 to placebo. 1104 participants discontinued treatment (464 assigned to the pioglitazone group, 501 in the placebo high risk group, and 139 in the placebo low risk group). 3399 participants had at least one dose of study drug or placebo and at least one post-baseline follow-up visit, and were included in the efficacy analysis. 3465 participants were included in the safety analysis (1531 assigned to the pioglitazone group, 1507 in the placebo high risk group, and 427 in the placebo low risk group). In the full analysis set, 46 (3·3%) of 1406 participants at high risk given placebo had mild cognitive impairment due to Alzheimer's disease, versus four (1·0%) of 402 participants at low risk given placebo (hazard ratio 3·26, 99% CI 0·85–12·45; p=0·023). 39 (2·7%) of 1430 participants at high risk given pioglitazone had mild cognitive impairment, versus 46 (3·3%) of 1406 participants at high risk given placebo (hazard ratio 0·80, 99% CI 0·45–1·40; p=0·307). In the safety analysis set, seven (0·5%) of 1531 participants at high risk given pioglitazone died versus 21 (1·4%) of 1507 participants at high risk given placebo. There were no other notable differences in adverse events between groups. The study was terminated in January, 2018, after failing to meet the non-futility threshold. Interpretation: Pioglitazone did not delay the onset of mild cognitive impairment. The biomarker algorithm demonstrated a 3 times enrichment of events in the high risk placebo group compared with the low risk placebo group, but did not reach the pre-specified significance threshold. Because we did not complete the study as planned, findings can only be considered exploratory. The conduct of this study could prove useful to future clinical development strategies for Alzheimer's disease prevention studies. Funding: Takeda and Zinfandel