Pai, Rish K.

Abstract Background and Aims The NASH Clinical Research Network histologic scoring system, the gold‐standard NASH histology assessment for clinical trials, has demonstrated intrarater and interrater variability. An expert panel in a previous systematic Research and Development/University of California Los Angeles (RAND/UCLA) study determined that existing histologic scoring systems do not fully capture NASH disease activity and fibrosis, and standardized definitions of histologic features are needed. We evaluated the reliability of existing and alternate histologic measures and their correlations with a disease activity visual analog scale to propose optimal components for an expanded NAFLD activity score (NAS). Approach and Results Four liver pathologists who were involved in the prior RAND/UCLA study underwent standardized training and multiple discussions with the goal of improving agreement. They were blinded to clinical information and scored histologic measures twice, ≥2 weeks apart, for 40 liver biopsies representing the full spectrum of NAFLD. Index intraclass correlation coefficient (ICC) estimates demonstrated intrarater (0.80–0.85) and interrater (0.60–0.72) reliability. Hepatocyte ballooning items had similar interrater ICCs (0.68–0.79), including those extending scores from 0–2 to 0–4. Steatosis measures (interrater ICCs, 0.72–0.80) correlated poorly with disease activity. Correlations with disease activity were largest for hepatocyte ballooning and Mallory‐Denk bodies (MDBs), with both used to develop the expanded NAS (intrarater ICC, 0.90; interrater ICC, 0.80). Fibrosis measures had ICCs of 0.70–0.87. Conclusions After extensive preparation among a group of experienced pathologists, we demonstrated improved reliability of multiple existing histologic NAFLD indices and fibrosis staging systems. Hepatocyte ballooning and MDBs most strongly correlated with disease activity and were used for the expanded NAS. Further validation including evaluation of responsiveness is required.

Immune checkpoint inhibitor-associated colitis (ICIC) affects approximately 15% of cancer patients treated with immunotherapy. Although histological evaluation is potentially valuable for both the diagnosis of ICIC and evaluation of disease activity, use in clinical practice is heterogeneous. We aimed to develop expert recommendations to standardize histological assessment of disease activity in patients with ICIC. Using the modified Research and Development/University of California Los Angeles (RAND/UCLA) appropriateness methodology, an international panel of 11 pathologists rated the appropriateness of 99 statements on a 9-point Likert scale during two rounds of anonymous voting. Results were discussed between rounds using moderated videoconferences. There are currently no disease-specific instruments for assessing histological features of ICIC. The panel considered that colonoscopy with at least three biopsies per segment from a total of at least five segments, including both endoscopically normal and inflamed areas, was appropriate for tissue acquisition. They agreed that biopsies should be oriented such that the long axis of the colonic crypts is visualized and should be stained with hematoxylin and eosin. Histological items that the panel voted were appropriate to evaluate in ICIC included the degree of structural/architectural change, chronic inflammatory infiltrate, lamina propria and intraepithelial neutrophils, crypt abscesses and destruction, erosions/ulcerations, apoptosis, surface intraepithelial lymphocytosis, and subepithelial collagen thickness. The appropriateness of routine immunohistochemistry was uncertain. These expert recommendations will help standardize assessment of histological activity in patients with ICIC. The panel also identified the development and validation of an ICIC-specific histological index as a research priority.

Abstract Background: The etiology of colorectal cancer is not fully understood. Methods: Using genetic variants and metabolomics data including 217 metabolites from the Framingham Heart Study (n = 1,357), we built genetic prediction models for circulating metabolites. Models with prediction R2 > 0.01 (Nmetabolite = 58) were applied to predict levels of metabolites in two large consortia with a combined sample size of approximately 46,300 cases and 59,200 controls of European and approximately 21,700 cases and 47,400 controls of East Asian (EA) descent. Genetically predicted levels of metabolites were evaluated for their associations with colorectal cancer risk in logistic regressions within each racial group, after which the results were combined by meta-analysis. Results: Of the 58 metabolites tested, 24 metabolites were significantly associated with colorectal cancer risk [Benjamini–Hochberg FDR (BH-FDR) < 0.05] in the European population (ORs ranged from 0.91 to 1.06; P values ranged from 0.02 to 6.4 × 10−8). Twenty one of the 24 associations were replicated in the EA population (ORs ranged from 0.26 to 1.69, BH-FDR < 0.05). In addition, the genetically predicted levels of C16:0 cholesteryl ester was significantly associated with colorectal cancer risk in the EA population only (OREA: 1.94, 95% CI, 1.60−2.36, P = 2.6 × 10−11; OREUR: 1.01, 95% CI, 0.99−1.04, P = 0.3). Nineteen of the 25 metabolites were glycerophospholipids and triacylglycerols (TAG). Eighteen associations exhibited significant heterogeneity between the two racial groups (PEUR-EA-Het < 0.005), which were more strongly associated in the EA population. This integrative study suggested a potential role of lipids, especially certain glycerophospholipids and TAGs, in the etiology of colorectal cancer. Conclusions: This study identified potential novel risk biomarkers for colorectal cancer by integrating genetics and circulating metabolomics data. Impact: The identified metabolites could be developed into new tools for risk assessment of colorectal cancer in both European and EA populations.

LINKED CONTENTThis article is linked to Danese et al papers. To view these articles, visit https://doi.org/10.1111/apt.16753 and https://doi.org/10.1111/apt.16761

Abstract Background and Aims Ulcerative colitis [UC] is characterised by an unpredictable disease course and variable response to therapy. Recent studies suggest a role for eosinophils in both pathogenesis and predicting treatment response. The goal of this study was to determine the association between eosinophils and clinical outcomes in UC. Methods A systematic review of the literature from database inception to May 2021 was performed to identify all studies evaluating the relationship between eosinophils and/or eosinophil-derived proteins [EDPs] and clinical outcomes, such as disease activity, clinical relapse, severity of disease, and response to treatment. Results A total of 55 studies were identified. Of these, 34 studies evaluated the relationship between eosinophils in colonic tissue and outcomes and 15 in blood. Eighteen studies assessed the relationship between EDPs and outcomes. In 25 of 34 studies, a positive correlation between eosinophils and/or EDPs and disease activity was reported, three studies found a negative correlation, and nine studies found no correlation. Positive correlations between eosinophils and clinical relapse were shown in four of nine studies, and with disease outcome severity in five of seven studies. Four of 15 studies showed that subjects with higher eosinophil levels had a poor response to treatment. Conclusions These findings suggest that higher eosinophil levels may be associated with increased disease activity and poorer clinical outcomes and response to therapy. Future studies are needed to determine whether a distinct eosinophil-rich UC phenotype exists and whether eosinophil-targeted therapy can alter the disease course.

Abstract Background There is a scarcity of data regarding the role of histopathology evaluation in Crohn’s disease (CD) and how it relates to endoscopy. Mirikizumab (miri) has shown efficacy in Ph2 studies in CD and ulcerative colitis (UC). Here we explore the agreement of histologic response and remission with endoscopic outcomes after 12 and 52 weeks of treatment with miri in a phase 2 randomized clinical trial (SERENTIY; NCT02891226) in patients with moderate-to-severe CD. Methods Patients were randomized 2:1:1:2 across 4 treatment arms (PBO, 200, 600, 1000mg miri) administered intravenously (IV) every four weeks (Q4W) at Weeks 0, 4, and 8. Those who received miri and achieved ≥1 point improvement from baseline (BL) at W12 in Simple Endoscopic Score for Crohn’s Disease (SES-CD) were re-randomized 1:1 into double-blind maintenance to continue their IV dose assignment Q4W (IV/IV) or to 300mg miri SC Q4W (IV/SC); due to small numbers, maintenance IV arms were pooled for analysis. W12 non-improvers and all induction PBO patients received 1000mg miri Q4W from W12 through W52. Biopsies were obtained during endoscopy at W0, 12 and 52 from the edge of the ulcers and the most inflamed mucosa in terminal ileum and 4 colonic segments (ascending, transverse, descending, rectum; N=10/patient, 2 per location with the more severe score used), and scored by central readers blind to study treatment, timepoint, and response status. Histologic endpoints were defined post-hoc but prior to performing the analyses (see Table footnotes for definitions). Cohen’s Kappa Coefficient was used to evaluate the degree of agreement of two measures. Results At Week 12, there was an overall 69.6% agreement in histologic and endoscopic response, and 84.2% agreement between histologic remission and endoscopic remission (Table 1). After 52 weeks of miri treatment, the agreement between histologic and endoscopic response was 61.9%, while the agreement between histologic and endoscopic remission was 70.6% (Table 2). Interestingly, in every comparison, the percentage of patients achieving the histologic outcome but not the endoscopic outcome was greater than that of patients achieving the endoscopic outcome but not the histologic outcome. Conclusion Histologic and endoscopic outcomes demonstrated fair association after both 12 and 52 weeks of miri treatment. Histologic endpoints, despite the stringent criteria, appear to be more sensitive to change than endoscopic endpoints. However, variability of biopsy sampling may be an additional factor contributing to these differences.

Abstract Background The role of histopathology evaluation in Crohn’s disease (CD) is not precisely defined. Due to the heterogeneity of phenotypes, the discontinuity of distribution, and the transmural nature of inflammation, the interpretation of histologic outcomes is complex. To analyze how histology relates to established outcomes in CD, we examined association between histologic and endoscopic disease activity measured by frequently used scores (simple endoscopic score for Crohn’s disease [SES-CD], Robarts histopathology index [RHI], global histological activity score [GHAS]) and the association between histologic or endoscopic severity with inflammatory biomarkers in a cohort of patients with moderate-to-severe CD. Methods Patients (N=191) who were enrolled in a phase 2 randomized clinical trial (NCT02891226) in patients with moderate-to-severe CD were assessed at baseline (BL) for endoscopic disease location and severity as measured by SES-CD. Biopsies were obtained during BL endoscopy from the edge of the ulcers and the most inflamed mucosa in terminal ileum and 4 colonic segments (ascending, transverse, descending, rectum; N=10/patient, 2 per location with the more severe score used), and scored by central readers blind to study treatment, timepoint, and response status using RHI and both modified and active GHAS (mGHAS: Q1, 3, 4, 5, 6; aGHAS: Q1, 4, 5, 6; see Fig. 1). Inflammatory biomarkers included fCLP and CRP; log-transformed values are used. Linear correlations between measures were determined using Pearson correlation coefficients (PCC) as exploratory analyses. Nominal p values are presented. Results SES-CD correlated well with all 3 histologic measures examined (Fig. 1). While both fCLP and CRP correlated more closely with endoscopy than with histologic measures, fCLP had higher correlation with each histologic measure than CRP (Fig. 2). 64% of patients had the same disease location at BL when measured by endoscopy or histology. Patients with endoscopic colonic disease displayed histologic ileal involvement in up to 20% of cases, while 13% of patients with endoscopic ileal disease demonstrated histologic colonic involvement (Table 1). Conclusion Although histologic disease activity in CD, as determined by 3 different measures, correlates well with endoscopic assessment of disease, histologic involvement provides complementary information on disease distribution and extension. Further analyses are required to understand the additive role of mucosal histology in CD.

Abstract Background Glycemic traits—such as hyperinsulinemia, hyperglycemia, and type 2 diabetes—have been associated with higher colorectal cancer risk in observational studies; however, causality of these associations is uncertain. We used Mendelian randomization (MR) to estimate the causal effects of fasting insulin, 2-hour glucose, fasting glucose, glycated hemoglobin (HbA1c), and type 2 diabetes with colorectal cancer. Methods Genome-wide association study summary data were used to identify genetic variants associated with circulating levels of fasting insulin (n = 34), 2-hour glucose (n = 13), fasting glucose (n = 70), HbA1c (n = 221), and type 2 diabetes (n = 268). Using 2-sample MR, we examined these variants in relation to colorectal cancer risk (48 214 case patient and 64 159 control patients). Results In inverse-variance models, higher fasting insulin levels increased colorectal cancer risk (odds ratio [OR] per 1-SD = 1.65, 95% confidence interval [CI] = 1.15 to 2.36). We found no evidence of any effect of 2-hour glucose (OR per 1-SD = 1.02, 95% CI = 0.86 to 1.21) or fasting glucose (OR per 1-SD = 1.04, 95% CI = 0.88 to 1.23) concentrations on colorectal cancer risk. Genetic liability to type 2 diabetes (OR per 1-unit increase in log odds = 1.04, 95% CI = 1.01 to 1.07) and higher HbA1c levels (OR per 1-SD = 1.09, 95% CI = 1.00 to 1.19) increased colorectal cancer risk, although these findings may have been biased by pleiotropy. Higher HbA1c concentrations increased rectal cancer risk in men (OR per 1-SD = 1.21, 95% CI = 1.05 to 1.40), but not in women. Conclusions Our results support a causal effect of higher fasting insulin, but not glucose traits or type 2 diabetes, on increased colorectal cancer risk. This suggests that pharmacological or lifestyle interventions that lower circulating insulin levels may be beneficial in preventing colorectal tumorigenesis.

SummaryBackgroundEpithelial barrier dysfunction contributes to a dysregulated intestinal immune response in ulcerative colitis (UC). GB004 is an orally administered, small molecule, gut‐targeted stabiliser of hypoxia‐inducible factor‐1α, a transcription factor with protective roles at the epithelial layer of the inflamed gut.AimsTo evaluate safety, pharmacokinetics, pharmacodynamics and efficacy of GB004 in patients with active UC.MethodsThis double‐blind, placebo‐controlled study randomised patients 2:1 to receive an oral solution of GB004 120 mg or placebo once daily for 28 days. Eligible patients had a Robarts Histopathology Index score ≥4 with neutrophils in the epithelium, total Mayo Clinic score 3‐12, Mayo Clinic endoscopic subscore ≥1, and blood in the stool, despite treatment with 5‐aminosalicylates, corticosteroids or immunosuppressants.ResultsThirty‐four patients were randomised. GB004 120 mg for 28 days was generally well‐tolerated. Adverse events occurred in 27.3% (3/11) and 39.1% (9/23) of patients in the placebo and GB004 groups respectively. Nausea and dysgeusia were most commonly reported in the GB004 group (0% for placebo and 21.7% [5/23] and 13.0% [3/23] respectively for GB004). There were no treatment‐related serious adverse events or deaths. GB004 exhibited minimal accumulation, with higher colonic concentrations relative to plasma. Exploratory pharmacodynamic and efficacy analyses demonstrated GB004 target engagement and numerically higher proportions of patients achieving improvement in multiple measures of disease activity, respectively, at day 28 for GB004 compared to placebo.ConclusionResults from this phase 1b trial support evaluation of the full therapeutic potential of GB004 for the treatment of UC. A phase 2 study (NCT04556383) is ongoing. Clinicaltrials.gov NCT03860896.

AbstractBackgroundThe incidence of colorectal cancer (CRC) among individuals aged younger than 50 years has been increasing. As screening guidelines lower the recommended age of screening initiation, concerns including the burden on screening capacity and costs have been recognized, suggesting that an individualized approach may be warranted. We developed risk prediction models for early-onset CRC that incorporate an environmental risk score (ERS), including 16 lifestyle and environmental factors, and a polygenic risk score (PRS) of 141 variants.MethodsRelying on risk score weights for ERS and PRS derived from studies of CRC at all ages, we evaluated risks for early-onset CRC in 3486 cases and 3890 controls aged younger than 50 years. Relative and absolute risks for early-onset CRC were assessed according to values of the ERS and PRS. The discriminatory performance of these scores was estimated using the covariate-adjusted area under the receiver operating characteristic curve.ResultsIncreasing values of ERS and PRS were associated with increasing relative risks for early-onset CRC (odds ratio per SD of ERS = 1.14, 95% confidence interval [CI] = 1.08 to 1.20; odds ratio per SD of PRS = 1.59, 95% CI = 1.51 to 1.68), both contributing to case-control discrimination (area under the curve = 0.631, 95% CI = 0.615 to 0.647). Based on absolute risks, we can expect 26 excess cases per 10 000 men and 21 per 10 000 women among those scoring at the 90th percentile for both risk scores.ConclusionsPersonal risk scores have the potential to identify individuals at differential relative and absolute risk for early-onset CRC. Improved discrimination may aid in targeted CRC screening of younger, high-risk individuals, potentially improving outcomes.