Senescent cancer-associated fibroblasts in pancreatic adenocarcinoma restrict CD8+ T cell activation and limit responsiveness to immunotherapy in mice.

Senescent cells within tumors and their stroma exert complex pro- and anti-tumorigenic functions. However, the identities and traits of these cells, and the potential for improving cancer therapy through their targeting, remain poorly characterized. Here, we identify a senescent subset within previously-defined cancer-associated fibroblasts (CAFs) in pancreatic ductal adenocarcinomas (PDAC) and in premalignant lesions in mice and humans. Senescent CAFs isolated from mouse and humans expressed elevated levels of immune-regulatory genes. Depletion of senescent CAFs, either genetically or using the Bcl-2 inhibitor ABT-199 (venetoclax), increased the proportion of activated CD8+ T cells in mouse pancreatic carcinomas, whereas induction of CAF senescence had the opposite effect. Combining ABT-199 with an immune checkpoint therapy regimen significantly reduced mouse tumor burden. These results indicate that senescent CAFs in PDAC stroma limit the numbers of activated cytotoxic CD8+ T cells, and suggest that their targeted elimination through senolytic treatment may enhance immunotherapy.

Low ALT Is Associated with IBD and Disease Activity: Results from a Nationwide Study.

Background: Sarcopenia is underdiagnosed in patients with inflammatory bowel disease (IBD). Low alanine transaminase (ALT) is associated with sarcopenia. We evaluated the association between low ALT and the presence of IBD and disease activity. Methods: Data were collected from a national Israeli health insurer cohort comprising 976,615 patients. Patients with a diagnosis of IBD were compared to healthy controls. After exclusion of patients with liver disease, ALT > 40 IU/L and age < 18, a total of 233,451 patients were included in the analysis. Low ALT was defined as <10 IU/L. Results: Low ALT was more common amongst patients with IBD than in healthy controls (7.76% vs. 5.7% p < 0.001). Low ALT was found in 148 (7.9%) of the patients with CD and 69 (6.9%) of the patients with UC. For CD, low ALT was associated with increased fecal calprotectin (FC) and CRP (223.00 µg/mg [63.45-631.50] vs. 98.50 [31.98-324.00], p < 0.001, 9.10 mg/L [3.22-19.32] vs. 3.20 [1.30-8.30], p < 0.001) and decreased albumin and hemoglobin (3.90 g/dL [3.60-4.20] vs. 4.30 [4.00-4.50], p < 0.001,12.20 g/dL [11.47-13.00] vs. 13.60 [12.60-14.70], p < 0.001). For UC, low ALT was associated with higher FC and CRP (226.50 µg/mg [143.00-537.00] vs. 107.00 [40.85-499.50], p = 0.057, 4.50 mg/L [1.90-11.62] vs. 2.30 [1.00-6.20], p < 0.001) and with lower albumin and hemoglobin (4.00 g/dL [3.62-4.18] vs. 4.30 [4.10-4.40], p < 0.001, 12.40 g/dL [11.60-13.20] vs. 13.60 [12.60-14.60], p < 0.001). These findings remained consistent following multivariate regression and in a propensity score-matched cohort. Conclusions: Low ALT is more common in patients with IBD and is associated with biochemical disease activity indices.

A computer-aided polyp detection system in screening and surveillance colonoscopy: an international, multicentre, randomised, tandem trial.

BACKGROUND: Studies on the effect of computer-aided detection (CAD) in a daily clinical screening and surveillance colonoscopy population practice are scarce. The aim of this study was to evaluate a novel CAD system in a screening and surveillance colonoscopy population. METHODS: This multicentre, randomised, controlled trial was done in ten hospitals in Europe, the USA, and Israel by 31 endoscopists. Patients referred for non-immunochemical faecal occult blood test (iFOBT) screening or surveillance colonoscopy were included. Patients were randomomly assigned to CAD-assisted colonoscopy or conventional colonoscopy; a subset was further randomly assigned to undergo tandem colonoscopy: CAD followed by conventional colonoscopy or conventional colonoscopy followed by CAD. Primary objectives included adenoma per colonoscopy (APC) and adenoma per extraction (APE). Secondary objectives included adenoma miss rate (AMR) in the tandem colonoscopies. The study was registered at ClinicalTrials.gov, NCT04640792. FINDINGS: A total of 916 patients were included in the modified intention-to-treat analysis: 449 in the CAD group and 467 in the conventional colonoscopy group. APC was higher with CAD compared with conventional colonoscopy (0·70 vs 0·51, p=0·015; 314 adenomas per 449 colonoscopies vs 238 adenomas per 467 colonoscopies; poisson effect ratio 1·372 [95% CI 1·068-1·769]), while showing non-inferiority of APE compared with conventional colonoscopy (0·59 vs 0·66; p<0·001 for non-inferiority; 314 of 536 extractions vs 238 of 360 extractions). AMR in the 127 (61 with CAD first, 66 with conventional colonoscopy first) patients completing tandem colonoscopy was 19% (11 of 59 detected during the second pass) in the CAD first group and 36% (16 of 45 detected during the second pass) in the conventional colonoscopy first group (p=0·024). INTERPRETATION: CAD increased adenoma detection in non-iFOBT screening and surveillance colonoscopies and reduced adenoma miss rates compared with conventional colonoscopy, without an increase in the resection of non-adenomatous lesions. FUNDING: Magentiq Eye.