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Inflammation and obesity are two major factors that promote Colorectal cancer (CRC). Our recent data suggests that interleukin (IL)-23, is significantly elevated in CRC tumors and correlates with patient obesity, tumor grade and survival. Thus, we hypothesize that obesity and CRC may be linked via inflammation and IL-23 may be a potential target for intervention in high-risk patients. TCGA dataset and patient sera were evaluated for IL-23A levels. IL-23A [IL-23 p19 -/- ] knockout (KO) mice were crossed to Apc min/+ mice and progeny were fed low-fat or high-fat diets. At termination intestines were evaluated for tumorigenesis. Tumors, serum, and fecal contents were analyzed for protein biomarkers, cytokines, and microbiome profile respectively. IL-23A levels are elevated in the sera of patients with obesity and colon tumors. Genetic ablation of IL-23A significantly suppressed colonic tumor multiplicity (76-96 %) and incidence (72-95 %) in male and female mice. Similarly, small-intestinal tumor multiplicity and size were also significantly reduced in IL-23A KO mice. IL-23A knockdown in Apc min/+ mice fed high-fat diet, also resulted in significant suppression of colonic (50-58 %) and SI (41-48 %) tumor multiplicity. Cytokine profiling showed reduction in several circulating pro-inflammatory cytokines including loss of IL-23A. Biomarker analysis suggested reduced tumor cell proliferation and immune modulation with an increase in tumor-infiltrating CD4+ and CD8+ T-lymphocytes in the IL-23A KO mice compared to controls. Fecal microbiome analysis revealed potentially beneficial changes in the bacterial population profile. In summary, our data indicates a tumor promoting role for IL-23 in CRC including diet-induced obesity. With several IL-23 targeted therapies in clinical trials, there is a great potential for targeting this cytokine for CRC prevention and therapy., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

Colorectal cancer causes over 53,000 deaths annually in the United States. Its rising incidences worldwide and particularly in young adults is a major concern. Here, we evaluated the efficacy of omeprazole that is clinically approved for treating acid reflux, to enable its repurposing for colorectal cancer prevention. In the azoxymethane-induced rat colorectal cancer model, dietary omeprazole (250 and 500 ppm) was administered at early adenoma stage (8 weeks after azoxymethane) to assess the progression of early lesions to adenocarcinoma. Administration of omeprazole at 250 or 500 ppm doses led to suppression of total colon adenocarcinoma incidence by 15.7% and 32% ( P < 0.01), respectively. Importantly, invasive carcinoma incidence was reduced by 59% ( P < 0.0005) and 90% ( P < 0.0001) in omeprazole-administered rats in a dose-dependent manner. There was also a strong and dose-dependent inhibition in the adenocarcinoma multiplicity in rats exposed to omeprazole. Administration of 250 and 500 ppm omeprazole inhibited total colon adenocarcinoma multiplicity by approximately 49% and approximately 65% ( P < 0.0001), respectively. While noninvasive adenocarcinomas multiplicity was suppressed by approximately 34% to approximately 48% ( P < 0.02), the invasive carcinomas multiplicity was reduced by approximately 74% to approximately 94% ( P < 0.0001) in omeprazole-exposed rats in comparison with the untreated rats. Biomarker analysis results showed a decrease in cell proliferation and anti-apoptotic/pro-survival proteins with an increase in apoptosis. Transcriptome analysis of treated tumors revealed a significant increase in adenocarcinoma inhibitory genes (Olmf4; Spink4) expression and downregulation of progression promoting genes (SerpinA1, MMP21, IL6). In summary, omeprazole showed significant protection against the progression of adenoma to adenocarcinoma. PREVENTION RELEVANCE: Preventing colon cancer is urgently needed because of its high incidence and mortality rates worldwide. Toward this end, preventive efficacy of omeprazole, a common medication, was evaluated in animal model of colorectal cancer and was found to suppress colonic adenoma progression to carcinoma. These findings warrant its further evaluation in humans., (©2021 American Association for Cancer Research.)

Recent observational studies suggest that bisphosphonates (BP) and antidiabetic drugs are associated with colorectal cancer risk reduction. Hence, we evaluated the colorectal cancer preventive effects of BPs (zometa and fosamax), individually and when combined with metformin, in azoxymethane-induced rat colon cancer model. Rat (30/group) were randomized and treated subcutaneously with azoxymethane to induce colorectal cancer. Dietary intervention with zometa or fosamax (0, 20, or 100 ppm) or metformin (1,000 ppm) or the combinations (zometa/fosamax 20 ppm plus metformin 1,000 ppm) began 4 weeks after azoxymethane treatment, at premalignant lesions stage. Rats were killed 40 weeks post drug intervention to assess colorectal cancer preventive efficacy. Dietary zometa (20 ppm) inhibited noninvasive adenocarcinomas multiplicity by 37% ( P < 0.03) when compared with control diet fed group. Fosamax at 20 ppm and 100 ppm significantly reduced adenocarcinoma incidence ( P < 0.005) and inhibited the noninvasive adenocarcinoma multiplicities by 43.8% ( P < 0.009) and 60.8% ( P < 0.004), respectively, compared with the group fed control diet. At 1,000 ppm dose, metformin failed to suppress colon adenocarcinoma formation. However, the lower dose combinations of zometa or fosamax with metformin resulted in significant inhibition of noninvasive adenocarcinoma by 48% ( P < 0.006) and 64% ( P < 0.0002), and invasive adenocarcinoma by 49% ( P < 0.0005) and 38% ( P < 0.006), respectively. Biomarker analysis of combination drug-treated tumors showed a decrease in cell proliferation with increased apoptosis when compared with untreated tumors. Overall, our results suggest that the combination of low doses of zometa or fosamax with metformin showed synergistic effect and significantly inhibited colon adenocarcinoma incidence and multiplicity., (©2019 American Association for Cancer Research.)

Chronic use of aspirin and related drugs to reduce cancer risk is limited by unwanted side effects. Thus, we assessed the efficacy associated with different dosing regimens of aspirin and naproxen. Azoxymethane (AOM)-rat colon cancer model was used to establish the pharmacodynamic efficacy of aspirin and naproxen under different dosing regimens. Colon tumors were induced in rats (36/group) by two weekly doses of AOM. At the early adenoma stage, rats were fed diets containing aspirin (700 and 1,400 ppm) or naproxen (200 and 400 ppm), either continuously, 1 week on/1 week off, or 3 weeks on/3 weeks off, or aspirin (2,800 ppm) 3 weeks on/3 weeks off. All rats were euthanized 48 weeks after AOM treatment and assessed for efficacy and biomarkers in tumor tissues. Administration of aspirin and naproxen produced no overt toxicities. Administration of different treatment regimens of both agents had significant inhibitory effects with clear dose-response effects. Aspirin suppressed colon adenocarcinoma multiplicity (both invasive and noninvasive) by 41% ( P < 0.003) to 72% ( P < 0.0001) and invasive colon adenocarcinomas by 67%-91% ( P < 0.0001), depending on the treatment regimen. Naproxen doses of 200 and 400 ppm inhibited invasive adenocarcinoma multiplicity by 53%-88% ( P < 0.0001), depending on the dosing regimen. Colonic tumor biomarker analysis revealed that proliferation (proliferating cell nuclear antigen and p21), apoptosis (p53 and Caspase-3), and proinflammatory mediators (IL1β and prostaglandin E 2 ) were significantly correlated with the tumor inhibitory effects of aspirin and naproxen. Overall, our results suggest that intermittent dosing regimens with aspirin or naproxen demonstrated significant efficacy on the progression of adenomas to adenocarcinomas, without gastrointestinal toxicities., (©2019 American Association for Cancer Research.)

Every year more than a million new cancer cases and 600,000 deaths are reported world-wide. Colorectal cancer is the fourth most commonly occurring and second leading cause of cancer deaths in the United States. Significant progress has been made in understanding colorectal cancer through epidemiological, laboratory and clinical studies. Development of metastatic adenocarcinomas is a multistage process occurring over several years during which multiple genetic alterations and pathophysiological changes are associated. Colorectal cancer can be prevented if the transformation of normal colonic crypt cells to malignant can be halted or reversed. Some of the key molecules that are altered significantly and play important roles in colorectal tumor progression are associated with inflammation. Since chronic inflammation is now recognized as a potential risk factor for tumor development, targeting inflammatory pathways has proven effective in preventing formation of colonic tumors and their malignant progression in both preclinical and clinical studies. Synthetic non-steroidal anti-inflammatory drugs (NSAIDS) have been identified as potential colorectal cancer chemopreventive agents; however, most of these synthetic agents are associated with unwanted and sometimes fatal side effects. There is mounting evidence in support of the efficacy of naturally-occurring phytochemicals possessing anti-inflammatory activity. In this review we discuss key inflammatory pathways associated with colorectal cancer and promising naturally-occurring phytochemicals as anti-inflammatory agents for the prevention and treatment of colorectal cancer.