Abstract Globally, gastric adenocarcinoma is the fourth leading cause of cancer mortality and a major cancer disparity in the United States. Chemoprevention strategies are lacking for high-risk individuals with gastric premalignant conditions (GPMC). Curcumin, the principal curcuminoid in turmeric, exerts immunomodulatory effects in the epithelium and against Helicobacter pylori, and studies suggest chemoprevention potential. We conducted a double-blind, phase IIa randomized controlled trial in high-risk populations in Puerto Rico and Honduras. We investigated the utility of a bioavailable formulation of curcumin (Meriva) among individuals with H. pylori–negative GPMC, specifically, multifocal atrophic gastritis (MAG) or gastric intestinal metaplasia (GIM). Patients were 1:1 randomized to 1,000 mg Meriva daily or placebo for a 6-month intervention with endoscopy at baseline and 6 months. Outcomes included assessment of epithelial cytokine and chemokine levels, histology, and DNA damage as assessed by γ-H2AX phosphorylation IHC. Of the 110 subjects screened, 50 participants were randomized, and 48 completed the trial. A significant reduction in gastric mucosal IL1β levels from baseline in the gastric body, the primary endpoint, was observed in the Meriva group (P = 0.032). Changes in epithelial IL8, TNFα, and inducible protein 10 levels and gastric mucosal histology and DNA damage (secondary endpoints) were similar between arms. Curcumin (Meriva) was safe, well-tolerated, and showed potential as a curcuminoid chemoprevention agent in H. pylori–negative patients with GPMC. A potential reduction in gastric inflammation as measured by gastric mucosal IL1β levels was observed. Further studies are warranted, including studies in H. pylori–positive individuals, based upon the curcuminoid direct effects on H. pylori. Prevention Relevance: Gastric adenocarcinoma is a leading cause of cancer mortality worldwide. Chemoprevention candidates for GPMCs are limited. This randomized phase IIa trial evaluated a bioavailable curcumin formulation in high-risk individuals with MAG and GIM. The results support further study of curcuminoids for gastric cancer risk reduction. See related Spotlight, p. 387 See related article by Morgan et al., p. 391
Phase II Trial of Encapsulated Rapamycin to Reduce Polyp Burden Associated with Familial Adenomatous Polyposis
Abstract Purpose: Familial adenomatous polyposis (FAP) confers a significant risk of colorectal/duodenal cancer. Encapsulated rapamycin (eRapa) has demonstrated promise as FAP chemoprevention in early clinical studies. Patients and Methods: Thirty patients with FAP enrolled to three dosing regimens of eRapa (0.5 mg): cohort 1—every other day, cohort 2—daily every other week, or cohort 3—daily. The primary endpoints were safety/tolerability, pharmacokinetics, and percentage change from baseline (PCFB) in colorectal polyp burden (CPB) at 6 months. Secondary endpoints included PCFB total (TPB) and duodenal (DPB) polyp burden and change in International Society for Gastrointestinal Hereditary Tumors stage and Spigelman score at 6 and 12 months. Results: Twenty nine of thirty patients (97%) completed the 12-month study with predictable bioavailability. Low-grade adverse events were frequent but most pronounced in daily dosing. Two patients discontinued treatment related to toxicity. Cohort 1 had the largest decrease median PCFB CPB, DPB, and TPB at 6 months: −39.4 % (IQR, 108.9; P = 0.28), −33.33 % (IQR, 90; P = 0.04), and −38.6 % (IQR, 88.5; P = 0.26), respectively. At 12 months, cohort 2 had the largest decrease median PCFB CPB and TPB: −29.3 % (IQR, 67.6; P = 0.37) and −26.3 % (IQR, 49.5; P = 0.29), respectively. Intermittent dosing cohorts (1 and 2) reduced DPB at 6 months (P = 0.04) and improved TPB at 12 months (P = 0.05) compared with daily dosing. Conclusions: eRapa was safe, tolerable, and showed preliminary efficacy for FAP chemoprevention. The 0.5 mg daily every-other-week schedule will be evaluated in an upcoming phase III trial.
Adiposity distribution and risks of 12 obesity-related cancers: a Mendelian randomization analysis
Abstract Introduction There is convincing evidence that overall adiposity increases the risks of several cancers. Whether the distribution of adiposity plays a similar role is unclear. Methods We used 2-sample Mendelian randomization (MR) to examine causal relationships of 5 adiposity distribution traits (abdominal subcutaneous adipose tissue (ASAT); visceral adipose tissue (VAT); gluteofemoral adipose tissue (GFAT); liver fat; and pancreas fat) with the risks of 12 obesity-related cancers (endometrial, ovarian, breast, colorectal, pancreas, multiple myeloma, liver, kidney (renal cell), thyroid, gallbladder, esophageal adenocarcinoma, and meningioma). Results Sample size across all genome-wide association studies (GWAS) ranged from 8407 to 728 896 (median: 57 249). We found evidence that higher genetically predicted ASAT increased the risks of endometrial cancer, liver cancer, and esophageal adenocarcinoma (odds ratios (OR) and 95% confidence intervals (CI) per standard deviation (SD) higher ASAT = 1.79 (1.18 to 2.71), 3.83 (1.39 to 10.53), and 2.34 (1.15 to 4.78), respectively). Conversely, we found evidence that higher genetically predicted GFAT decreased the risks of breast cancer and meningioma (ORs and 95% CIs per SD higher genetically predicted GFAT = 0.77 (0.62 to 0.97) and 0.53 (0.32 to 0.90), respectively). We also found evidence for an effect of higher genetically predicted VAT and liver fat on increased liver cancer risk (ORs and 95% CIs per SD higher genetically predicted adiposity trait = 4.29 (1.41 to 13.07) and 4.09 (2.29 to 7.28), respectively). Discussion Our analyses provide novel insights into the relationship between adiposity distribution and cancer risk. These insights highlight the potential importance of adipose tissue distribution alongside maintaining a healthy weight for cancer prevention.
A prediction model for metachronous colorectal cancer: development and validation
Abstract Background Being able to estimate the risk of metachronous disease in a patient with colorectal cancer (CRC) could enable risk-appropriate surveillance. The aim of this study was to develop a risk-prediction model to estimate individual 10-year risk of metachronous disease following a CRC diagnosis. Methods A population-based cohort of patients with CRC was recruited soon after diagnosis between 1997 and 2012 from the United States, Canada, and Australia. Cox regression with the least absolute shrinkage and selection operator penalization was used to identify factors that predicted the risk of a new primary CRC diagnosed at least 1 year after the initial CRC diagnosis. Potential predictors included demography, anthropometry, lifestyle factors, comorbidities, personal and family cancer history, medication use, age at diagnosis, and pathological features of the first CRC. Internal validation through bootstrapping was used to evaluate the discrimination and calibration. Results We included 6085 CRC cases; 138 (2.3%) of these cases were diagnosed with metachronous disease over a median of 12 years (IQR = 5-17 years). Metachronous CRC risk was predicted by body mass index; smoking status; level of physical activity; family history of cancer and synchronous CRC; stage, grade, histological type, and DNA mismatch repair status; and age at diagnosis of the first CRC. The model was valid with a C statistic of 0.65 (95% CI = 0.63 to 0.68) and a calibration slope of 0.873 (SD = 0.087). Conclusions Metachronous CRC can be predicted with reasonable accuracy using a prediction model that consists of clinical variables collected as part of routine practice.
Menopausal hormone therapy: assessing associations with breast and colorectal cancers by familial risk
Abstract Menopausal users of hormone replacement therapy (HRT) are at increased breast cancer risk and decreased colorectal cancer (CRC) risk compared with individuals who have never used HRT, but these opposing associations may differ by familial risk of breast cancer and CRC. We harmonized data from 3 cohorts and generated separate breast cancer and CRC familial risk scores based on cancer family history. We defined moderate or strong family history as a risk score of 0.4 or higher, where 0.4 was equivalent to a 50-year-old woman with 1 parent diagnosed with either breast cancer or CRC at 55 years of age. Of 24 486 women assessed, 1243 and 405 were diagnosed with incident breast cancer and CRC, respectively. For breast cancer, menopausal HRT ever use versus never use hazard ratios were 1.27 (95% CI = 1.11 to 1.45) for a breast cancer familial risk score below 0.4 and 1.01 (95% CI = 0.82 to 1.25) for a breast cancer familial risk score of 0.4 or higher (Pdifference = .08). For CRC, menopausal HRT hazard ratios were 0.63 (95% CI = 0.50 to 0.78) for a CRC familial risk score below 0.4 and 1.21 (95% CI = 0.73 to 2.00) for a CRC familial risk score of 0.4 or higher (Pdifference = .03). Associations with menopausal HRT use that apply to the general population may not hold for women at moderate or strong familial risk of these cancers.
Plasma Ghrelin and Risks of Sex-Specific, Site-Specific, and Early-Onset Colorectal Cancer: A Mendelian Randomization Analysis
Abstract Background: Epidemiological and laboratory-based studies have provided conflicting evidence for a role of ghrelin in colorectal cancer development. We conducted two-sample Mendelian randomization (MR) analyses to evaluate evidence for an association of circulating ghrelin and colorectal cancer risk overall and by sex, cancer subsite, and age at diagnosis. Methods: Genetic instruments proxying plasma total ghrelin levels were obtained from a recent genome-wide association study of 54,219 participants. Summary data for colorectal cancer risk were obtained from a recent meta-analysis of several genetic consortia (up to 73,673 cases and 86,854 controls). A two-sample MR approach and several sensitivity analyses were applied. Results: We found no evidence for an association of genetically predicted plasma total ghrelin levels and colorectal cancer risk (0.95, 95% confidence interval, 0.81–1.12; R2 of ghrelin genetic instruments: 4.6%), with similarly null results observed when stratified by sex, anatomical subsite, and for early-onset colorectal cancer. Conclusions: Our study suggests that plasma ghrelin levels are unlikely to have a causal relationship with overall, early-onset, and sex- and cancer subsite–stratified colorectal cancer risk. Impact: This large-scale analysis adds to the growing body of evidence that plasma total ghrelin levels are not associated with colorectal cancer risk.
Methylated DNA Markers for Sporadic Colorectal and Endometrial Cancer Are Strongly Associated with Lynch Syndrome Cancers
Abstract Lynch syndrome (LS) markedly increases risks of colorectal and endometrial cancers. Early detection biomarkers for LS cancers could reduce the needs for invasive screening and surgical prophylaxis. To validate a panel of methylated DNA markers (MDM) previously identified in sporadic colorectal cancer and endometrial cancer for discrimination of these cancers in LS. In a case–control design, previously identified MDMs for the detection of colorectal cancer and endometrial cancer were assayed by qMSP on tissue-extracted DNA. Results were normalized to ACTB values within each sample. Least absolute shrinkage and selection operator models to classify colorectal cancer and endometrial cancer were trained on sporadic cases and controls and then applied to classify colorectal cancer and endometrial cancer, in those with LS, and cross-validated. We identified colorectal cancer cases (23 with LS, 48 sporadic), colorectal controls (32 LS, 48 sporadic), endometrial cancer cases (30 LS, 48 sporadic), and endometrial controls (29 LS, 37 sporadic). A 3-MDM panel (LASS4, LRRC4, and PPP2R5C) classified LS-CRC from LS controls with an AUC of 0.92 (0.84–0.99); results were similar for sporadic colorectal cancer. A 6-MDM panel (SFMBT2, MPZ, CYTH2, DIDO1, chr10.4479, and EMX2OS) discriminated LS-EC from LS controls with an AUC of 0.92 (0.83–1.0); the AUC for sporadic endometrial cancer versus sporadic controls was nominally higher, 0.99 (0.96–1.0). MDMs previously identified in sporadic endometrial cancer and colorectal cancer discriminate between endometrial cancer and benign endometrium and colorectal cancer and benign colorectum in LS. This supports the inclusion of patients with LS within future prospective clinical trials evaluating endometrial cancer and colorectal cancer MDMs and may provide a new avenue for cancer screening or surveillance in this high-risk population. Prevention Relevance: Lynch syndrome (LS) markedly increases risks of colorectal and endometrial cancers. Early detection biomarkers for LS cancers could reduce the needs for invasive screening and surgery. Methylated DNA markers previously identified in sporadic endometrial cancer and colorectal cancer discriminate between benign and cancer tissue in LS.