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The BRAF V600E mutation has been associated with microsatellite instability and the CpG island methylator phenotype (CIMP) in colon cancer. We evaluated a large populationbased sample of individuals with colon cancer to determine its relationship to survival and other clinicopathologic variables. The V600E BRAF mutation was seen in 5% (40 of 803) of microsatellite-stable tumors and 51.8% (43 of 83) of microsatellite-unstable tumors. In microsatellite-stable tumors, this mutation was related to poor survival, CIMP high, advanced American Joint Committee on Cancer (AJCC) stage, and family history of colorectal cancer [odds ratio, 4.23; 95% confidence interval (95% CI), 1.65-10.84]. The poor survival was observed in a univariate analysis of 5-year survival (16.7% versus 60.0%; P < 0.01); in an analysis adjusted for age, stage, and tumor site [hazard rate ratio (HRR), 2.97; 95% CI, 2.05-4.32]; in stage-specific, age-adjusted analyses for AJCC stages 2 to 4 (HRR, 4.88, 3.60, and 2.04, respectively); and in Kaplan-Meier survival estimates for AJCC stages 2 to 4 (P < 0.01 for all three stages). Microsatellite-unstable tumors were associated with an excellent 5-year survival whether the V600E mutation was present or absent (76.2% and 75.0%, respectively). We conclude that the BRAF V600E mutation in microsatellite-stable colon cancer is associated with a significantly poorer survival in stages 2 to 4 colon cancer but has no effect on the excellent prognosis of microsatelliteunstable tumors. (Cancer Res 2005; 65(14): 6063-9)

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Adopting a diet that is low in fat and high in fiber, fruits, and vegetables does not influence the risk of recurrence of colorectal adenomas.

Colon cancer has been associated with several nutrients and foods. The authors used data from a population-based study conducted in Northern California, Utah, and Minnesota to examine associations between dietary eating patterns and risk of developing colon cancer. Through factor analysis, detailed dietary intake data obtained from 1,993 cases (diagnosed in 1991-1994) and 2,410 controls were grouped into factors that were evaluated for relations with lifestyle characteristics and colon cancer risk. Several dietary patterns emerged. The dietary patterns with the most variation were labeled "Western," "prudent," "high fat/sugar dairy," "substituters," and "drinkers." The "Western" dietary pattern was associated with a higher body mass index and a greater intake of total energy and dietary cholesterol. The "prudent" pattern was associated with higher levels of vigorous leisure time physical activity, smaller body size, and higher intakes of dietary fiber and folate. Persons who had high scores on the "drinker" pattern were also more likely to smoke cigarettes. The "Western" dietary pattern was associated with an increased risk of colon cancer in both men and women. The association was strongest among people diagnosed prior to age 67 years (for men, odds ratio (OR)=1.96, 95% confidence interval (CI) 1.22-3.15; for women, OR=2.02, 95% CI 1.21-3.36) and among men with distal tumors (OR=2.25, 95% CI 1.47-3.46). The "prudent" diet was protective, with the strongest associations being observed among people diagnosed prior to age 67 years (men: OR=0.63, 95% CI 0.43-0.92; women: OR=0.58, 95% CI 0.38-0.87); associations with this dietary pattern were also strong among persons with proximal tumors (men: OR=0.55, 95% CI 0.38-0.80; women: OR=0.64, 95% CI 0.45-0.92). Although "substituters" (people who substituted low fat dairy products for high fat dairy products, margarine for butter, poultry for red meat, and whole grains for refined grains) were at reduced risk of colon cancer, the reduction in risk was not statistically significant. These data support the hypothesis that overall dietary intake pattern is associated with colon cancer, and that the dietary pattern associated with the greatest increase in risk is the one which typifies a Western-style diet.

To further dissect the genetic architecture of colorectal cancer (CRC), we performed whole-genome sequencing of 1,439 cases and 720 controls, imputed discovered sequence variants and Haplotype Reference Consortium panel variants into genome-wide association study data, and tested for association in 34,869 cases and 29,051 controls. Findings were followed up in an additional 23,262 cases and 38,296 controls. We discovered a strongly protective 0.3% frequency variant signal at CHD1 . In a combined meta-analysis of 125,478 individuals, we identified 40 new independent signals at P <5×10 −8 , bringing the number of known independent signals for CRC to approximately 100. New signals implicate lower-frequency variants, Krüppel-like factors, Hedgehog signaling, Hippo-YAP signaling, long noncoding RNAs, somatic drivers, and support a role of immune function. Heritability analyses suggest that CRC risk is highly polygenic, and larger, more comprehensive studies enabling rare variant analysis will improve understanding of underlying biology, and impact personalized screening strategies and drug development.

Fiber consumption predicted insulin levels, weight gain, and other CVD risk factors more strongly than did total or saturated fat consumption. High-fiber diets may protect against obesity and CVD by lowering insulin levels.