Limburg, Paul J.

Abstract Colorectal cancer (CRC) is a heterogenous disease that develops through somatic mutations in driver genes, leading to activation of diverse neoplastic pathways. To systematically examine if somatically mutated genes and pathways impact survival, we sequenced tumor and normal DNA samples for 4,512 CRC cases using a targeted panel. We performed Cox regression to estimate hazard ratios (HR) and 95% confidence intervals (CIs) for associations of disease-specific (DS)-survival with somatically mutated genes and pathways, adjusting for age and sex, and stratifying baseline hazards by study population. We assessed statistical significance using Bonferroni p-value thresholds to account for multiple testing of 214 genes (2.34x10-4) and 6 key CRC pathways (8.3x10-3). We limited analyses to non-silent mutations. We observed that DS-survival was significantly more favorable among individuals with hypermutated (HM) tumors, primarily consisting of microsatellite unstable and POLE-mutated tumors, as compared to those with non-hypermutated (NHM) tumors (HR=0.4, 95% CI: 0.3-0.5, p=1.2x10-17). BRAF V600E mutations were associated with poorer survival (HR=2.0, 95% CI: 1.6-2.5, p=1.6x10-10). This association was more pronounced among NHM tumors (HR=2.3, 95% CI: 1.8-2.9, p=4.3x10-12). We identified suggestive associations (p-values < 5.0x10-3 in overall or stratified analyses) between DS-survival and mutations in B2M, TP53, and SMAD4. Mutations in B2M may provide more favorable prognosis for survival (HR=0.5, 95% CI: 0.3-0.8, p=4.4x10-3), with similar effect sizes in HM and NHM tumors. Poorer survival may be associated with mutations in TP53 (HR=1.2, 95% CI:1.2-1.4, p=9.3x10-4) and SMAD4 (HR=1.3, 95% CI:1.1-1.6, p=3.2x10-3) in NHM tumors. We further observed statistically significant associations between survival and three mutated pathways: TP53/ATM (HR=1.2, 95% CI:1.1-1.4, p=9.0x10-4), receptor tyrosine kinases (RTK) and RAS (HR=1.3, 95% CI:1.1-1.5, p=4.5x10-5), and TGF-beta (HR=1.3, 95% CI:1.1-1.5, p=2.9x10-4). Findings for TP53/ATM and RTK/RAS were primarily due to mutations in one gene within each pathway (TP53 and BRAF, respectively). However, the TGF-beta pathway finding, which was more pronounced in NHM tumors, included two genes with p-values less than 0.05 (SMAD4 p=3.2x10-3 and TGFBR2 p=0.01). Despite our large sample size, relatively few somatically mutated genes were significantly associated with DS-survival. It may be that pathway-level testing affords more power for analyses and that larger sample sizes are needed. It is of interest that non-silent mutations in B2M, whose product is a component of the class I major histocompatibility complex, was associated with improved DS-survival, though our finding was not statistically significant after multiple testing correction so further exploration and replication is needed. Citation Format: Tabitha A. Harrison, Syed H. Zaidi, Conghui Qu, Amanda I. Phipps, Robert S. Steinfelder, Quang M. Trinh, Sonja I. Berndt, Daniel D. Buchanan, Peter T. Campbell, Andrew T. Chan, Kim F. Doheny, David A. Drew, Jane C. Figueiredo, Steven J. Gallinger, Marios Giannakis, Andrea Gsur, Marc J. Gunter, Michael Hoffmeister, Wen-Yi Huang, Paul J. Limburg, Victor Moreno, Polly A. Newcomb, Shuji Ogino, Ross L. Prentice, Tameka Shelford, Wei Sun, Stephen N. Thibodeau, Li Hsu, Ulrike Peters. Associations of somatically mutated genes and pathways with colorectal cancer specific survival in 4,500 colorectal cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB090.

Diabetics tend to have inadequate fruit consumption, elevated plasma glucose and insulin, and increased cardiovascular disease risk. Dried fruit may represent one way to increase fruit consumption among diabetics. Polydextrose is a commonly used soluble fiber and bulking agent providing very little available carbohydrate energy. The glycemic and insulinemic response of type 2 diabetics (n=13) to a single serving of white bread (57g; 160 Cal; 1 g fiber), raw cranberries (RC; 55g; 21 Cal; 1 g fiber), sweetened dried cranberries‐original (SCDO; 40g, 138 Cal; 2.1g fiber), and SDC‐less sugar (SDCLS; 40g; 113 Cal; 1.8g fiber + 10g polydextrose) was measured in a single cross‐over design. Plasma glucose (mg/dl) and insulin ( μU/ml) was measured prior to consumption, then 30, 60 and 120 minutes postprandially. Plasma glucose peaked at 30 or 60 min following bread, RC, SDCO, and SDCLS at 175 ± 10, 127 ± 7, 175 ± 10 and 158 ± 9 min, respectively, and remained significantly elevated 120 min following bread consumption. Peak plasma insulin for SDCO (15 ± 2) and RC (10 ± 1) was significantly less than bread (22 ± 2) or SDCO (22 ± 4), and remained slightly elevated at 120 minutes. The area under the curve values reflected similar changes. SDCLS consumption could be useful for improving fruit consumption by type 2 diabetics in a manner that provides glycemic and insulinemic benefits. Sponsor: Ocean Spray Cranberries Inc.

Persons with metabolic syndrome could benefit from improved fruit consumption and reduced caloric intake. A cranberry fruit containing reduced titratable acidity was developed and used to create a 27% reduced calorie cranberry juice (RCCBJ) containing less added sugar (74 Cal/240 ml) relative to the 110 Cal/240 ml industry standard cranberry juice (CBJ). Subjects were recruited for metabolic syndrome (n=18; 53 16 years; BMI=34.4 ± 3.9) and their metabolic response to CBJ and RCCBJ was evaluated in single cross‐over fashion. Plasma glucose for CBJ at 0‐, 30‐, 60‐, and 120‐min was 105.6±12.3, 149.5±22.6, 127.9±30.3, and 98.6±14.6 (mg/dl). Plasma glucose for RCCBJ was 104.6±13.3, 140.3±22.5, 116.0±27.23, and 100.4±13. Plasma insulin for CBJ at 0‐, 30‐, 60‐, and 120‐ min was 10.21±5.1, 41.5±22.6, 30.3±19.7, and 12.0± (µIU/ml). Plasma insulin for RCCBJ was 12.2±8.4, 34.8±21.6, 20.7±13.9, and 12.3±9.8. For CBJ and RCCBJ plasma glucose and insulin significantly increased relative to baseline at 30‐ and 60‐min. At 60 min RCCBJ glucose and insulin were significantly less than CBJ. Plasma adiponectin and glucagon like peptide‐1 responses were also measured for CBJ and RCCBJ at 0‐, 30‐, 60‐, and 120‐min. Reduced acidity cranberry fruit was associated with RCCBJ containing 33% fewer calories and a beneficial metabolic response in persons with metabolic syndrome.

Mono‐and polyunsaturated fats in nuts, such as pistachios (PI), may improve lipoprotein and glycemic status. Overweight persons trend for dyslipidemia and high diabetes risk. The lower limits of PI consumption required for health benefits are unknown. This study determined if PI at bedtime promotes beneficial changes in metabolic status in overweight persons. Overweight subjects (n=22; 55 ± 2 yrs; 90 ± 3.6 kg; BMI 31 ± 1) were randomized to 35.4 g PI self‐administered at bedtime or control (CO; no PI) for 6 weeks. There was no difference in physical activity level between subjects receiving PI and CO. Body weight was not different in PI and CO at wk 0, 1, 2, 4, and 6. HDL cholesterol at wk 0 and 6 in PI was 49.2 ± 3.5 to 50.3 ± 3.0, and CO was 60.8 ± 3.8 and 58.0 ± 2.7 mg/dL, at wk 6 PI had improved slightly relative to CO (P= 0.12). Plasma glucose at wk 0 and 6 in PI was 104.6 ± 2.8 and 99.6 ± 2.6 mg/dL, and CO was 102.0 ± 2.8 and 101.1 ± 2.6 mg/dL, at wk 6 PI had improved slightly relative to CO (P= 0.16). Plasma insulin at wk 0 and 6 in PI was 8.5 ± 1.0 and 8.4 ± 0.9, and CO was 7.2 ± 0.7 to 8.8 ± 0.7 μU/mL, at wk 6 PI had improved slightly relative to CO (P = 0.21). Beneficial changes in HDL, glucose, and insulin probably requires slightly more than 35.4 g/d PI for 6 wks. To increase the probability of metabolic health benefits, nutritionists may wish to encourage levels of daily PI consumption higher than those administered in this study.

10545 Background: Approximately 20–30% of colorectal cancers (CRC) arise from the serrated polyp pathway. The multitarget stool DNA (mt-sDNA) test has greater sensitivity to detect sessile serrated polyps (SSPs) than a leading fecal immunochemical test (FIT). However, most modeling analyses do not account for the contribution of the SSP pathway to risk of CRC. We used the CRC-AIM model to assess the impact of the SSP pathway on predicted CRC outcomes with mt-sDNA or FIT screening. Methods: A simulated cohort of average-risk US patients underwent triennial mt-sDNA or annual FIT screening from ages 50–75. The percentage of CRCs arising from the SSP pathway were modeled at 0% (base case), 20%, and 30%, with stool screening adherence based on theoretical (100%) or previously reported (mt-sDNA 71%; FIT 43%) rates. Published SSP sensitivities for mt-sDNA and FIT were used. All other model inputs were identical to CISNET models. Sensitivity analyses used screening adherence rates of 40–70%. Key outcomes were life-years gained (LYG), CRC incidence and CRC mortality per 1000 patients. Results: Including SSPs in the model demonstrated a greater loss of LYG with FIT than mt-sDNA (Table). At 100% adherence, compared with base case, modeling 20% or 30% SSP pathway CRCs resulted in a decrease of 9–15 LYG with FIT and 2–4 LYG with mt-sDNA, a decrease in CRC incidence reduction of 3.9–6.1% with FIT and 0.7–1.1% with mt-sDNA, and a decrease in CRC mortality reduction of 2.6–4.0% with FIT and 0.4–0.8% with mt-sDNA. Using previously reported adherence, compared with base case, modeling 20% or 30% SSP pathway CRCs resulted in a decrease of 13–20 LYG with FIT and 2–5 LYG with mt-sDNA, a decrease in CRC incidence reduction of 4.4–6.9% with FIT and 0.6–1.1% with mt-sDNA, and a decrease in CRC mortality reduction of 3.5–5.4% with FIT and 0.4–0.9% with mt-sDNA. Assuming reported adherence and 30% SSP pathway CRCs, mt-sDNA had 48 more LYG, 14.6% greater CRC incidence reduction, and 12.4% greater CRC mortality reduction than FIT. Assuming 30% SSP pathway CRCs, outcomes favored mt-sDNA vs FIT even after modeling equivalent adherence rates ranging from 40–70%. Conclusions: After incorporating the SSP pathway into the model, outcomes with mt-sDNA neared those of FIT at 100% screening adherence rates and surpassed FIT at more realistic reported screening adherence rates.[Table: see text]

Abstract Colorectal cancer–screening models commonly assume 100% adherence, which is inconsistent with real-world experience. The influence of adherence to initial stool-based screening [fecal immunochemical test (FIT), multitarget stool DNA (mt-sDNA)] and follow-up colonoscopy (after a positive stool test) on colorectal cancer outcomes was modeled using the Colorectal Cancer and Adenoma Incidence and Mortality Microsimulation Model. Average-risk individuals without diagnosed colorectal cancer at age 40 undergoing annual FIT or triennial mt-sDNA screening from ages 50 to 75 were simulated. Primary analyses incorporated published mt-sDNA (71%) or FIT (43%) screening adherence, with follow-up colonoscopy adherence ranging from 40% to 100%. Secondary analyses simulated 100% adherence for stool-based screening and colonoscopy follow-up (S1), published adherence for stool-based screening with 100% adherence to colonoscopy follow-up (S2), and published adherence for both stool-based screening and colonoscopy follow-up after positive mt-sDNA (73%) or FIT (47%; S3). Outcomes were life-years gained (LYG) and colorectal cancer incidence and mortality reductions (per 1,000 individuals) versus no screening. Adherence to colonoscopy follow-up after FIT had to be 4%–13% higher than mt-sDNA to reach equivalent LYG. The theoretical S1 favored FIT versus mt-sDNA (LYG 316 vs. 297; colorectal cancer incidence reduction 68% vs. 64%; colorectal cancer mortality reduction 76% vs. 72%). The more realistic S2 and S3 favored mt-sDNA versus FIT (S2: LYG 284 vs. 245, colorectal cancer incidence reduction 61% vs. 50%, colorectal cancer mortality reduction 69% vs. 59%; S3: LYG 203 vs. 113, colorectal cancer incidence reduction 43% vs. 23%, colorectal cancer mortality reduction 49% vs. 27%, respectively). Incorporating realistic adherence rates for colorectal cancer screening influences modeled outcomes and should be considered when assessing comparative effectiveness. Prevention Relevance: Adherence rates for initial colorectal cancer screening by FIT or mt-sDNA and for colonoscopy follow-up of a positive initial test influence the comparative effectiveness of these screening strategies. Using adherence rates based on published data for stool-based testing and colonoscopy follow-up yielded superior outcomes with an mt-sDNA versus FIT-screening strategy.