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BackgroundThe methodology used in the first Belgian food consumption survey followed to a large extent the instructions of the European Food Consumption (EFCOSUM) reports, where repeated 24-hour recalls (24HR) using EPIC-SOFT were recommended.ObjectivesTo evaluate the relative validity of two non-consecutive 24HR using EPIC-SOFT by comparison with 5-day estimated dietary records (EDR). To assess misreporting in energy for both methods by comparing energy intake with energy expenditure from accelerometery in a subsample.DesignA total of 175 subjects (aged 15 and over) were recruited to participate in the study. Repeated 24HR were performed with an interval of 2–8 weeks. After completion of the second interview, subjects were instructed to keep an EDR. Dietary intakes were adjusted for within-person variability to reflect usual intakes. A Student's t-test was calculated to assess differences between both methods. Spearman and Kappa correlation coefficients were used to investigate agreement.ResultsIn total, 127 subjects completed the required repeated 24HR, as well as the five record days. From 76 participants, accelerometer data were available. In both methods, about 35% of participants had ratios of Energy Intake/Total Energy Expenditure (EI/TEE) above or below 95% confidence intervals for EI/TEE, suggesting misreporting of energy. Significant differences between the two dietary intake methods were found for total energy, total fat, fatty acids, cholesterol, alcohol, vitamin C, thiamine, riboflavin and iron. In general, intakes from 24HR were higher compared to EDR. Correlation coefficients for all nutrients ranged from 0.16 for thiamine to 0.70 for water.ConclusionsThe results from this study show that in the context of nutritional surveillance, duplicate 24HR can be used to asses intakes of protein, carbohydrates, starch, sugar, water, potassium and calcium.

The RAS/RAF/MEK/MAPK and the PTEN/PI3K/AKT/mTOR pathways are key regulators of proliferation and survival in human cancer cells. Selective inhibitors of different transducer molecules in these pathways have been developed as molecular targeted anti-cancer therapies. The in vitro and in vivo anti-tumor activity of pimasertib, a selective MEK 1/2 inhibitor, alone or in combination with a PI3K inhibitor (PI3Ki), a mTOR inhibitor (everolimus), or with multi-targeted kinase inhibitors (sorafenib and regorafenib), that block also BRAF and CRAF, were tested in a panel of eight human lung and colon cancer cell lines. Following pimasertib treatment, cancer cell lines were classified as pimasertib-sensitive (IC 50 for cell growth inhibition of 0.001 mM) or pimasertib-resistant. Evaluation of basal gene expression profiles by microarrays identified several genes that were up-regulated in pimasertib-resistant cancer cells and that were involved in both RAS/RAF/MEK/MAPK and PTEN/PI3K/ AKT/mTOR pathways. Therefore, a series of combination experiments with pimasertib and either PI3Ki, everolimus, sorafenib or regorafenib were conducted, demonstrating a synergistic effect in cell growth inhibition and induction of apoptosis with sustained blockade in MAPK-and AKT-dependent signaling pathways in pimasertib-resistant human colon carcinoma (HCT15) and lung adenocarcinoma (H1975) cells. Finally, in nude mice bearing established HCT15 and H1975 subcutaneous tumor xenografts, the combined treatment with pimasertib and BEZ235 (a dual PI3K/mTOR inhibitor) or with sorafenib caused significant tumor growth delays and increase in mice survival as compared to single agent treatment. These results suggest that dual blockade of MAPK and PI3K pathways could overcome intrinsic resistance to MEK inhibition.The RAS/RAF/MEK/MAPK and PTEN/PI3K/AKT/mTOR signaling pathways play central roles in the intracellular transduction of proliferative signals from activated cell membrane growth factor receptors to the nucleus in both normal and cancer cells. RAF is a serine/threonine kinase that activates down-stream signals in response to activated GTP-bound RAS by phosphorylating MEK1 and MEK2, which in turn phosphorylate and activate MAPK (or ERK1 and ERK2). ERK kinases phosphorylate a number of cellular substrates with key roles in cell proliferation and survival. The phosphoinositide 3-kinases (PI3Ks) are a family of lipid kinases that propagate intracellular signaling cascades regulating a wide range of cellular processes. PI3K phosphorylates the 3 0 -OH group on phosphatidylinositols in the plasma membrane. This leads to recruitment of AKT, a serine/ threonine kinase, to the cell membrane where it becomes

Purpose BRAFV600E mutations are associated with poor clinical prognosis in colorectal cancer (CRC). Whereas selective BRAF inhibitors are effective for treatment of melanoma, comparable efforts in CRC have been disappointing. Here, we investigated potential mechanisms underlying this resistance to BRAF inhibitors in BRAFV600E CRC. Experimental Design We examined phosphatidyl inositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling in BRAFV600E CRC cell lines after BRAF inhibition and cell viability and apoptosis after combined BRAF and PI3K/mTOR inhibition. We assessed the efficacy of in vivo combination treatment using a novel genetically engineered mouse model (GEMM) for BRAFV600E CRC. Results Western blot revealed sustained PI3K/mTOR signaling upon BRAF inhibition. Our BRAFV600E GEMM presented with sessile serrated adenomas/polyps, as seen in humans. Combination treatment in vivo resulted in induction of apoptosis and tumor regression. Conclusions We have established a novel GEMM to interrogate BRAFV600E CRC biology and identify more efficacious treatment strategies. Combination BRAF and PI3K/mTOR inhibitor treatment should be explored in clinical trials.