Apc Min Mice Research Articles

Upregulation of Fatty Acid Synthase Increases Activity of β-Catenin and Expression of NOTUM to Enhance Stem-like Properties of Colorectal Cancer Cells.

Dysregulated fatty acid metabolism is an attractive therapeutic target for colorectal cancer (CRC). We previously reported that fatty acid synthase (FASN), a key enzyme of de novo synthesis, promotes the initiation and progression of CRC. However, the mechanisms of how upregulation of FASN promotes the initiation and progression of CRC are not completely understood. Here, using Apc/VillinCre and ApcMin mouse models, we show that upregulation of FASN is associated with an increase in activity of β-catenin and expression of multiple stem cell markers, including Notum. Genetic and pharmacological downregulation of FASN in mouse adenoma organoids decreases the activation of β-catenin and expression of Notum and significantly inhibits organoid formation and growth. Consistently, we demonstrate that NOTUM is highly expressed in human CRC and its expression positively correlates with the expression of FASN in tumor tissues. Utilizing overexpression and shRNA-mediated knockdown of FASN, we demonstrate that upregulation of FASN increases β-catenin transcriptional activity, NOTUM expression and secretion, and enhances stem-like properties of human CRC cells. Pharmacological inhibition of NOTUM decreases adenoma organoids growth and proliferation of cancer cells. In summary, upregulation of FASN enhances β-catenin signaling, increases NOTUM expression and stem-like properties of CRC cells, thus suggesting that targeting FASN upstream of the β-catenin/NOTUM axis may be an effective preventative therapeutic strategy for CRC.

Stable Dietary Ora-Curcumin Formulation Protects from Experimental Colitis and Colorectal Cancer.

Inflammatory bowel disease (IBD) is a chronic gut disorder that also elevates the risk of colorectal cancer (CRC). The global incidence and severity of IBD are rising, yet existing therapies often lead to severe side effects. Curcumin offers potent anti-inflammatory and chemotherapeutic properties. However, its clinical translation is hindered by rapid metabolism, as well as poor water solubility and stability, which limits its bioavailability. To address these challenges, we developed OC-S, a water-soluble and colon-targeted curcumin formulation that protects against colitis in mice. The current study advances OC-S as a dietary supplement by establishing its stability and compatibility with various commercial dietary products. Further, OC-S exhibited specific binding to inflamed colon tissue, potentially aiding in targeted drug retention at the inflammation site in colitis with diarrhea symptoms. We further investigated its efficacy in vivo and in vitro using a murine model of colitis and tumoroids from APCmin mice. OC-S significantly reduced colitis severity and pro-inflammatory cytokine expression compared with curcumin, even at very low doses (5 mg/kg/day). It also demonstrated higher anti-proliferative activity in CRC cells and colon cancer tumoroids vs. curcumin. Overall, this study demonstrated that OC-S effectively targets and retains water-soluble curcumin at the inflamed colon sites, while showing promise in addressing both colitis and colorectal cancer, which potentially paves the way for OC-S to advance into clinical development as a dietary product for both IBD and CRC.

Abstract 1259: HMGA1: An epigenetic gatekeeper of Wnt signals during colon tumorigenesis and regeneration

Abstract Cancer cells undergo epigenetic reprogramming to co-opt stem cell networks and drive tumor progression, although how this occurs remains unclear. The High Mobility Group A1 (HMGA1) gene encodes an architectural transcription factor that binds to DNA at AT-rich sequences where it recruits chromatin complexes to modulate gene expression. HMGA1 is highly expressed during embryogenesis and in adult stem cells, but silenced in differentiated cells. HMGA1 becomes re-expressed in aggressive cancers where high levels portend adverse outcomes. In colorectal cancer (CRC), HMGA1 is among the genes most highly overexpressed compared to normal colon epithelium. We previously discovered that HMGA1 is required for oncogenic phenotypes in CRC cell lines by inducing genes involved in an epithelial-mesenchymal transition. Hmga1 transgenic mice also develop aberrant proliferation and polyposis of small intestinal epithelium where Hmga1 amplifies Wnt signals to enhance self-renewal. To determine how HMGA1 functions in colon epithelial homeostasis and tumorigenesis, we examined mouse models with overexpression or deficiency of Hmga1. Here, we uncover a previously unknown role for HMGA1 as an epigenetic gatekeeper of Wnt signals in colon epithelial cells, both during tumorigenesis driven by mutant APC or stress-induced tissue repair. Strikingly, loss of just a single Hmga1 allele within the colon epithelium disrupts tumorigenesis while prolonging survival in two models of colon tumorigenesis driven by APC mutation, including CDX2P-CreERTCApcfl/fl and APCMin mice inoculated with pro-carcinogenic, enterotoxigenic Bacteroides fragilis. Single cell RNA sequencing in Apc mutant crypt epithelial cells reveals that intact Hmga1 is required for expansion in the Lgr5+ stem cell pool, deep secretory cells, and tuft cells during tumorigenesis. Hmga1 deficiency impacts the stem cell pool the greatest, decreasing Lgr5+ stem cells with skewing to more proliferative, transit amplifying-like cells. Single cell transcriptomic analyses together with assays of single cell chromatin accessibility demonstrate that Hmga1 maintains accessible chromatin to activate gene loci involved in Wnt signals, including Ascl2, a stem cell master regulator, Wnt agonist receptors, and Wnt downstream effectors. Surprisingly, either depletion or overexpression of Hmga1 has no impact on colon epithelial regeneration under homeostatic conditions, although Hmga1 overexpression enhances tissue repair and survival following injury induced by inflammation or irradiation. Together, our results establish HMGA1 as an epigenetic gatekeeper of Wnt signals in colon stem cells during APC-driven tumorigenesis or injury, but not steady state homeostasis, highlighting its role as a promising therapeutic target for both cancer and regenerative medicine. Citation Format: Linda M. S. Resar, Li Z. Luo, Lingling Xian, Iliana Herrera, Shaoguang Wu, Jung-Hyun Kim, Ying Feng, Julian Calderon-Espinosa, Eric R. Fearon, Cynthia Sears. HMGA1: An epigenetic gatekeeper of Wnt signals during colon tumorigenesis and regeneration [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1259.

Leucine Supplementation Exacerbates Morbidity in Male but Not Female Mice with Colorectal Cancer-Induced Cachexia.

Cancer cachexia (CC) is a multifactorial wasting syndrome characterized by a significant loss in lean and/or fat mass and represents a leading cause of mortality in cancer patients. Nutraceutical treatments have been proposed as a potential treatment strategy to mitigate cachexia-induced muscle wasting. However, contradictory findings warrant further investigation. The purpose of this study was to determine the effects of leucine supplementation on skeletal muscle in male and female ApcMin/+ mice (APC). APC mice and their wild-type (WT) littermates were given normal drinking water or 1.5% leucine-supplemented water (n = 4-10/group/sex). We measured the gene expression of regulators of inflammation, protein balance, and myogenesis. Leucine treatment lowered survival rates, body mass, and muscle mass in males, while in females, it had no effect on body or muscle mass. Leucine treatment altered inflammatory gene expression by lowering Il1b 87% in the APC group and decreasing Tnfa 92% in both WT and APC males, while it had no effect in females (p < 0.05). Leucine had no effect on regulators of protein balance and myogenesis in either sex. We demonstrated that leucine exacerbates moribundity in males and is not sufficient for mitigating muscle or fat loss during CC in either sex in the ApcMin/+ mouse.

Tumor-Promoting Role of GNA14 in Colon Cancer Development.

Recent studies have shown that mutations in members of the G-protein α family contribute to the onset and progression of cancer. However, the role of GNA14 in CRC remains unknown. In this study, we examined the effect of GNA14 on CRC through genetic approaches in vitro and in vivo. We found that GNA14 knockdown by small interfering RNA (siRNA) inhibited the proliferation of CRC cells SW403 and HT29. Gna14 knockout mice developed normally without obvious abnormalities. However, the number of polyps in the small intestine was significantly reduced in Gna14 knockout mice compared to control mice after mating with ApcMin mice, a representative CRC mouse model. In particular, deletion of the Gna14 inhibited polyp growth, especially in the distal end of the small intestine. Histological examination showed that Gna14 knockout mice suppressed malignant tumor progression due to decreased proliferation and increased apoptosis in polyps compared to controls. In addition, GNA14 knockdown in CRC cells resulted in downregulation of ERK phosphorylation and β-catenin and β-catenin phosphorylation at S675. Similarly, ERK phosphorylation and phospho-β-catenin phosphorylation at S675 were decreased in polyps of Gna14 knockout mice. Collectively, these analyses show that GNA14 may accelerate CRC cell proliferation and malignant tumor progression through ERK and β-catenin pathways.

If you give a mouse a mutation: comparing the therapeutic utility of renowned mouse models of human cancers

Cancers of the breast, prostate and intestinal tract account for most cancer-associated deaths in humans and represent several of the highest incidence human neoplasms. Therefore, understanding the underlying pathophysiology, including the formation and propagation of these cancers, is key to designing potential treatments. Over the last 50 years or more, genetically engineered mouse models (GEMMs) have been instrumental platforms to our discovery of neoplastic disease as many follow near-identical molecular and histological progression as human tumours. In this mini review, we summarize three key preclinical models and focus on some of the major findings in relation to clinical care. We discuss the MMTV-PyMT (polyomavirus middle T antigen) mouse, TRAMP (transgenic adenocarcinoma mouse prostate) mouse and APCMin (multiple intestinal neoplasm mutation of APC gene) mouse, which mimic breast, prostate and intestinal cancers, respectively. We aim to describe the significant contributions these GEMMs have made to our collective understanding of high-incidence cancers as well as briefly discuss the limitations of each model as a device for therapeutic discovery.

Abstract 4244: Black soybean seed coat extract suppress intestinal tumorigenesis in APCmin mice

Abstract Background: Colorectal cancer (CRC) is a major cause of cancer-related deaths in Japan and worldwide. Since CRC has been reported to have close relationship with diet, it seems significant to identify dietary constituents that might suppress occurrence of CRC. Recently, an epidemiological investigation for cancer incidence in Japan revealed that consumptions of black soybeans seem to reduce incidence of several cancers, especially colorectal cancer. Black soybeans coat extract (BE) is known to contain rich procyanidins which have many beneficial physiological activities such as anticancer effects. Therefore, we hypothesized that BE may have inhibitory effects to intestinal tumorigenesis and investigated using APCmin/+ mice models. Materials and Methods: APCmin/+ male mice in the C57BL/6 genetic background were obtained from Jackson Laboratories. APCmin/+ genotypes of each mouse were confirmed by polymerase chain reaction analysis (PCR) using DNA extracted from the tip of mouse tails. Mice were weighed weekly once and monitored regularly for any signs of weight loss. APC min/+ mice at 4 weeks of age were randomly divided into three groups with 5 mice, and fed by either AIN-76A diet, AIN-76A diet containing 0.05% or 0.05% BE for 8 weeks. At 12 weeks of age, intestines were removed from each mouse and then sliced longitudinally. The small intestine was cut into three equally parts: proximal, middle, and distal. Numbers and sizes of intestinal polyps in each portion were evaluated under Video-Zoom-microscope XV-440. Intestinal polyps were categorized by size into 1-2 mm, 2-3 mm and &amp;gt;3 mm. Other parts of the intestines were placed in 10% phosphate-buffered formalin for histopathology and immunohistochemical (PCNA, β-catenin, and MUC2) analyses. Results: Numbers of polyps in mice fed with containing 0.05% or 0.5% BE diet were significantly smaller than in mice fed without BE (P &amp;lt; 0.05). As for size of polyps, the number of polyps of 1 to 3 mm in size was decreased in mice with BE, however, there were no significant difference for numbers of polyps more than 3 mm in size regarding diets with or without BE. With 0.05% BE diet, reduction rates for occurrence of polyps were 81% for proximal, 48% for middle, and 47% for distal positions, while in with 0.5% BE diet, those reduction rates were 71% for proximal, 59% for middle, and 58% for distal positions, respectively. From these results, the BE, either 0.05% or 0.05% concentration, showed inhibitory effects for tumorigeneses in the small intestine of APC min/+ mice. In histological analyses, the BE was induced higher expression of MUC2-positive cells in normal intestinal lesions and lower expression of β-catenin in tumor sites Conclusions: The BE showed inhibitory effects in occurrence and growth of intestinal polyps in APCmin/+ mice models. With further evaluation of mechanisms, the BE could be a promising nutrition for prevention of CRC in human. Citation Format: Yasuyuki Shimizu, Shunta Hirano, Yoko Yamashita, Tsuyoshi Fukumoto, Naritoshi Mukumoto, Ai Nakaoka, Namiko Hoshi, Takeaki Ishihara, Daisuke Miyawaki, Ashida Hitoshi, Ryohei Sasaki. Black soybean seed coat extract suppress intestinal tumorigenesis in APCmin mice. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4244.

Novel read through agent: ZKN-0013 demonstrates efficacy in APCmin model of familial adenomatous polyposis.

Familial adenomatous polyposis (FAP) is a precancerous, colorectal disease characterized by hundreds to thousands of adenomatous polyps caused by mutations in the tumor suppressor gene adenomatous polyposis coli (APC). Approximately 30% of these mutations are premature termination codons (PTC), resulting in the production of a truncated, dysfunctional APC protein. Consequently, the β-catenin degradation complex fails to form in the cytoplasm, leading to elevated nuclear levels of β-catenin and unregulated β-catenin/wnt-pathway signaling. We present in vitro and in vivo data demonstrating that the novel macrolide, ZKN-0013, promotes read through of premature stop codons, leading to functional restoration of full-length APC protein. Human colorectal carcinoma SW403 and SW1417 cells harboring PTC mutations in the APC gene showed reduced levels of nuclear β-catenin and c-myc upon treatment with ZKN-0013, indicating that the macrolide-mediated read through of premature stop codons produced bioactive APC protein and inhibited the β-catenin/wnt-pathway. In a mouse model of adenomatous polyposis coli, treatment of APCmin mice with ZKN-0013 caused a significant decrease in intestinal polyps, adenomas, and associated anemia, resulting in increased survival. Immunohistochemistry revealed decreased nuclear β-catenin staining in the epithelial cells of the polyps in ZKN-0013-treated APCmin mice, confirming the impact on the β-catenin/wnt-pathway. These results indicate that ZKN-0013 may have therapeutic potential for the treatment of FAP caused by nonsense mutations in the APC gene. KEY MESSAGES: • ZKN-0013 inhibited the growth of human colon carcinoma cells with APC nonsense mutations. • ZKN-0013 promoted read through of premature stop codons in the APC gene. • In APCmin mice, ZKN-0013 treatment reduced intestinal polyps and their progression to adenomas. • ZKN-0013 treatment in APCmin mice resulted in reduced anemia and increased survival.

TET1 and TDG Suppress Inflammatory Response in Intestinal Tumorigenesis: Implications for Colorectal Tumors With the CpG Island Methylator Phenotype

Aberrant DNA methylation is frequent in colorectal cancer (CRC), but underlying mechanisms and pathologic consequences are poorly understood. We disrupted active DNA demethylation genes Tet1 and/or Tdg from ApcMin mice and characterized the methylome and transcriptome of colonic adenomas. Data were compared to human colonic adenocarcinomas (COAD) in The Cancer Genome Atlas. There were increased numbers of small intestinal adenomas in ApcMin mice expressing the TdgN151A allele, whereas Tet1-deficient and Tet1/TdgN151A-double heterozygous ApcMin colonic adenomas were larger with features of erosion and invasion. We detected reduction in global DNA hypomethylation in colonic adenomas from Tet1- and Tdg-mutant ApcMin mice and hypermethylation of CpG islands in Tet1-mutant ApcMin adenomas. Up-regulation of inflammatory, immune, and interferon response genes was present in Tet1- and Tdg-mutant colonic adenomas compared to control ApcMin adenomas. This up-regulation was also seen in murine colonic organoids and human CRC lines infected with lentiviruses expressing TET1 or TDG short hairpin RNA. A 127-gene inflammatory signature separated colonic adenocarcinomas into 4 groups, closely aligned with their microsatellite or chromosomal instability and characterized by different levels of DNA methylation and DNMT1 expression that anticorrelated with TET1 expression. Tumors with the CpG island methylator phenotype (CIMP) had concerted high DNMT1/low TET1 expression. TET1 or TDG knockdown in CRC lines enhanced killing by natural killer cells. Our findings reveal a novel epigenetic regulation, linked to the type of genomic instability, by which TET1/TDG-mediated DNA demethylation decreases methylation levels and inflammatory/interferon/immune responses. CIMP in CRC is triggered by an imbalance of methylating activities over demethylating activities. These mice represent a model of CIMP CRC.

Abstract IA016: Vaccine approach for the interception of colon cancer

Abstract This year, in the US, an estimated 150,000 people will be diagnosed with colon cancer and ~52,000 will die of the disease. A vaccine approach is well suited to colon cancer prevention. First, a limited number of immunizations can be given over a short period of time to achieve a desired immune response. If immunologic memory develops, antigen specific T-cells will persist in the body for years, ready to be deployed when aberrant cells are detected. Finally, there are several well-defined high-risk populations that would be suitable for testing a preventative colon cancer vaccine including individuals (1) with a hereditary genetic syndrome such as familial adenomatous polyposis, (2) with a history of inflammatory bowel disease such as Crohn’s disease or ulcerative colitis, and (3) those with a history of hyperplastic colonic polyps. Vaccines targeting virally mediated cancers are effective, in part, because T-cells are primed to proteins involved in oncogenesis. The most common type of colon adenoma and invasive cancer associated antigens are non-mutated growth-related proteins that become markedly overexpressed in the disease state. Genes which are aberrantly up-regulated and conserved from adenoma to invasive colon carcinoma may encode overexpressed proteins that are associated with colon cancer initiation. Evaluating gene expression data derived from over 600 colorectal cancers, matched normal tissues, and colon adenomas we identified 160 genes overexpressed in the majority of adenomas and early-stage colon cancers, but not in normal tissues. Using siRNA screening we demonstrated 35 of those genes, when silenced, resulted in apoptosis or inhibition of growth of colon cancer cells and an adenoma cell line but not a non-neoplastic colon cell line. Of those genes, 16 have been shown to encode proteins that are overexpressed in both adenomas and colon cancer and are associated with disease progression and over a third of these proteins are immunogenic. These proteins could serve as potential candidate antigens for inclusion in a multi-antigen vaccine. Recently, we have identified epitopes within the natural sequences of non-mutated tumor antigens that only generate Th1 (Th1 selective) antigen specific T-cells. This discovery and the development of high throughput methods to both identify and screen putative Class II binding peptides for Th selective function has allowed us to develop antigen specific Th1 selective vaccines. A vaccine targeting CDC25B, COX2, and EGFR can inhibit intestinal tumor formation in both APCmin mice and mice with tumor induced by AOM. Concomitant use of NSAIDs potentiates the immune response generated with vaccination. The anti-tumor response observed after vaccination is significantly correlated with elevated CD8 T-cells found in the lesions and induced by immunization as well as high magnitude antigen specific T-cells identified in the spleen. These data validate a genomic approach to antigen discovery and anti-tumor efficacy of Th1 selective vaccines for colon cancer prevention. Citation Format: Mary Disis, Ying Liu, Lauren Corulli, Erin Rodmaker, Denise Cecil. Vaccine approach for the interception of colon cancer. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr IA016.

Dietary inclusion of nitrite-containing frankfurter exacerbates colorectal cancer pathology and alters metabolism in APCmin mice

Colorectal cancer (CRC) is the second most prevelant malignancy in Europe and diet is an important modifiable risk factor. Processed meat consumption, including meats with preservative salts such as sodium nitrite, have been implicated in CRC pathogenesis. This study investigated how the CRC pathology and metabolic status of adenomatous polyposis coli (APC) multiple intestinal neoplasia (min) mice was perturbed following 8 weeks of pork meat consumption. Dietary inclusions (15%) of either nitrite-free pork, nitrite-free sausage, or nitrite-containing sausage (frankfurter) were compared against a parallel control group (100% chow). Comprehensive studies investigated: gastrointestinal tract histology (tumours), aberrant crypt foci (ACF), mucin deplin foci (MDF), lipid peroxidation (urine and serum), faecal microbiota, and serum metabolomics (599 metabolites). After 8 weeks mice consuming the frankfurter diet had 53% more (P = 0.014) gastrointestinal tumours than control, although ACF and MDF did not differ. Urine and serum lipid peroxidation markers were 59% (P = 0.001) and 108% (P = 0.001) higher, respectively in the frankfurter group. Gut dysbiosis was evident in these mice with comparably fewer Bacteriodes and more Firmicutes. Fasting serum levels of trimethylamine N-oxide (TMAO) and numerous triglycerides were elevated. Various serum phosphotidylcholine species were decreased. These results demonstrate that nitrite-containing sausages may exaccerbate the development of CRC pathology in APCMin mice to a greater extent than nitrite-free sausages, and this is associated with greater lipid peroxidation, wide-ranging metabolic alternation and gut dysbiosis.

The Barretos Cancer Hospital Animal Facility: Implementation and Results of a Dedicated Platform for Preclinical Oncology Models.

The Barretos Cancer Hospital Animal Facility (BCHAF) is a unique facility in Brazil exclusively dedicated to working with animal models for cancer research. In this article, we briefly present our modern facility and the main experiments performed, focusing on mutant strains of mice (PTCH-knockout and ApcMin mice), xenograft models, and patient-derived xenografts (PDXs). Our results show the progress and challenges in establishing these models and the need for having an appropriate representation of our cancer population to better understand tumor biology and to identify cancer biomarkers, which could be putatively targeted, allowing for personalized therapy.

Decreased NHE3 expression in colon cancer is associated with DNA damage, increased inflammation and tumor growth

Dysregulation of intra- and extracellular pH in cancer contributes to extracellular matrix remodeling, favors cell migration, proliferation, and metastasis. Although the primary attention has been focused on the role of the ubiquitous Na+/H+ exchanger isoform NHE1, the role of NHE3, the predominant apical isoform in colonic surface epithelium in the pathogenesis of colon cancer has not been investigated. Here, we show that NHE3 mRNA expression is significantly reduced in colorectal cancer patients and that low NHE3 expression is associated with poorer survival. Deletion of NHE3 in ApcMin mice evaluated at 15 weeks of age (significant mortality was observed beyond this time) led to lower body weights, increased mucosal inflammation, increased colonic tumor numbers, evidence of enhanced DNA damage in tumor surface epithelium, and to significant alteration in the gut microbiota. In the absence of the inflammatory and microbial pressors, ca. 70% knockdown of NHE3 expression in SK-CO15 cells led to reduced intracellular pH, elevated apical pH, dramatic differences in their transcriptomic profile, increased susceptibility to DNA damage, increased proliferation, decreased apoptosis and reduced adhesion to extracellular matrix proteins. Our findings suggest that loss of NHE3 in the surface epithelium of colonic tumors has profound consequences for cancer progression and behavior.

Extracellular Matrix Interactions Provide Tumor Cells With an Escape Mechanism for Commitment to Differentiation

Extracellular Matrix Interactions Provide Tumor Cells With an Escape Mechanism for Commitment to Differentiation

Abstract 3181: IL-23 knockdown profoundly suppresses intestinal tumorigenesis in APCmin mice

Abstract Colorectal cancer (CRC) is the 3rd most common cancer in the US with an estimated 149,500 new cases and 52,980 deaths in 2021. Studies show that Western-style diet-induced obesity promote CRC by modulating gut inflammatory mediators. We found significant increase in IL-23 levels (p&amp;lt;0.0001) in obese human subjects' plasma (n=15/arm; BMI&amp;gt;30) and its. over expression in colonic tumors (CT) from human and rodent models that highly correlated with, the TCGA gene expression &amp; disease-free survival data. These findings suggested IL-23 as a possible important link between obesity and colon tumorigenesis. The present study was designed to understand the role of IL-23 in colorectal carcinogenesis by using genetic knockout (KO) approach. For this study, Apcmin/+ and IL-23 KO mice were crossbred to generate Apcmin/+ mice with IL-23 in heterozygous or KO conditions. To determine the effect of IL-23 on intestinal tumorigenesis, six-week-old Apcmin/+ mice (N≥15/gender) were grouped by IL-23 genotype i.e., normal (+/+), heterozygous (+/-) and KO (-/-) conditions, then maintained under standard conditions. At 20 weeks of age, all mice were euthanized and intestines were evaluated and compared for tumors incidence and multiplicity. Genetic ablation of IL-23 led to significant suppression of large and small intestinal tumors of APCmin/+ mice in both genders. CT multiplicity of male and female IL-23+/+ Apcmin/+ mice were 1.35±0.16 (Mean±SEM) and 0.61±0.13, respectively. Male and female IL-23+/- Apcmin/+ mice had 77% (0.31+0.15; p&amp;lt;0.0001) and 90% (0.06+0.09; p&amp;lt;0.002) inhibition of CTs, respectively. Interestingly, IL-23 KO led to further suppression in male mice (96% inhibition in male; 0.05+0.05; p&amp;lt;0.0001 and 90% in females; 0.06+0.06; p&amp;lt;0.0001). While IL-23+/+ Apcmin/+ mice was 91% and 52% CT incidence in the male and female mice, respectively. CT incidence was suppressed by 72% (male, p&amp;lt;0.0001) &amp; 88% (female, p&amp;lt;0.005) in the IL-23+/- mice, with further suppression to 95% (male, p&amp;lt;0.0001) &amp; 89% (female, p&amp;lt;0.0025) inhibition in IL-23 KO mice. The strong suppressive effect of IL-23 knockdown was also observed on the small intestinal polyps (SIP) multiplicity. There was a 54% (12.56±1.64; p&amp;lt;0.0001) and 58% (11.45±1.03; p&amp;lt;0.0001) reduction in SIP number in IL23+/- and IL23-/- male Apcmin/+ mice, compared to the IL-23+/+ control mice (27.48±2.38). In female, 55-59% (13.88±1.05 and 12.73±2.03; p&amp;lt;0.0001) less SIP were observed with IL-23 ablation compared to control (30.90±2.54). Apcmin/+ with IL-23 KO showed significant reduction in circulating proinflammatory cytokine and chemokines (Ex: IL-1, IL-10, IL-17, IL-23, CCL-2, CCL-3, CCL-5, TNFa, IFNg) levels compared to IL-23 WT mice. These results clearly demonstrate the colon tumor-promoting role of IL-23 and strengthens our hypothesis to explore this target for CRC prevention in high-risk obese individuals. (Supported in part by P30 CA225520 and Kerley-Cade Endowed Chair) Citation Format: Venkateshwar Madka, Srikanth Chiliveru, Gopal Pathuri, Janani Panneerselvam, Rajani Rai, Nicole C. Stratton, Nandini B. Kumar, Yuting Zhang, Chinthalapally V Rao. IL-23 knockdown profoundly suppresses intestinal tumorigenesis in APCmin mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3181.

Highlights from Recent Cancer Literature

Breaking Insights| June 06 2022 Highlights from Recent Cancer Literature Author & Article Information Online Issn: 1538-7445 Print Issn: 0008-5472 ©2022 American Association for Cancer Research2022American Association for Cancer Research Cancer Res (2022) 82 (11): 2045–2046. https://doi.org/10.1158/0008-5472.CAN-82-11-BI Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Cite Icon Cite Search Site Article Versions Icon Versions Version of Record June 6 2022 Citation Highlights from Recent Cancer Literature. Cancer Res 1 June 2022; 82 (11): 2045–2046. https://doi.org/10.1158/0008-5472.CAN-82-11-BI Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest Search Advanced Search Only colorectal cancers that exhibit microsatellite instability (MSI high) respond to anti-PD1/PDL1 checkpoint blockade immunotherapy (CBI). The majority of MSI low colorectal cancers are unresponsive to CBI. Investigating the APCmin mouse and mouse tumor organoid models, Peuker and colleagues discovered additional T-cell checkpoints for immune resistance in colorectal cancer. Previous work identified the importance of the calcineurin-NFAT axis within cancer cells for colorectal cancer progression. This study demonstrated that calcineurin-NFAT enforced immunosuppression of antitumor CD8+ T cells. Myeloid-derived suppressor cells of the polymorphonuclear phenotype responded to microbiota cues (e.g., LPS) to produce IL6 in a calcineurin-NFAT–dependent manner. IL6 acted on tumor cells, inducing coinhibitory molecules B7H3 and B7H4 to block the function of CD8+ T cells. In patients with colorectal cancer, high B7H3 or B7H4 expression correlated with worse overall survival. Expert Commentary: Microbial sensing by tumor-infiltrating myeloid cells blocks T-cell responses to colorectal cancer by inducing... You do not currently have access to this content.

A non-dividing cell population with high pyruvate dehydrogenase kinase activity regulates metabolic heterogeneity and tumorigenesis in the intestine

Although reprogramming of cellular metabolism is a hallmark of cancer, little is known about how metabolic reprogramming contributes to early stages of transformation. Here, we show that the histone deacetylase SIRT6 regulates tumor initiation during intestinal cancer by controlling glucose metabolism. Loss of SIRT6 results in an increase in the number of intestinal stem cells (ISCs), which translates into enhanced tumor initiating potential in APCmin mice. By tracking down the connection between glucose metabolism and tumor initiation, we find a metabolic compartmentalization within the intestinal epithelium and adenomas, where a rare population of cells exhibit features of Warburg-like metabolism characterized by high pyruvate dehydrogenase kinase (PDK) activity. Our results show that these cells are quiescent cells expressing +4 ISCs and enteroendocrine markers. Active glycolysis in these cells suppresses ROS accumulation and enhances their stem cell and tumorigenic potential. Our studies reveal that aerobic glycolysis represents a heterogeneous feature of cancer, and indicate that this metabolic adaptation can occur in non-dividing cells, suggesting a role for the Warburg effect beyond biomass production in tumors.

COX-2 Inhibitors Decrease Expression of PD-L1 in Colon Tumors and Increase the Influx of Type I Tumor-infiltrating Lymphocytes.

Nonsteroidal anti-inflammatories (NSAID) are an essential component of any combination chemoprevention of colon cancer. We show NSAID treatment reduces PD-L1 expression on intestinal tumor cells. NSAID regulation of PD-L1 is dependent on COX-2 expression. These data underscore an important immunologic mechanism of action for NSAID in colon cancer prevention. See related Spotlight, p. 209.

Retracted: Lovastatin Inhibits RhoA to Suppress Canonical Wnt/β-Catenin Signaling and Alternative Wnt-YAP/TAZ Signaling in Colon Cancer

Statins are first-line drugs used to control patient lipid levels, but there is recent evidence that statin treatment can lower colorectal cancer (CRC) incidence by 50% and prolong CRC patient survival through mechanisms that are poorly understood. In this study, we found that the treatment of APCmin mice by the mevalonate pathway inhibitor lovastatin significantly reduced the number of colonic masses and improved hypersplenism and peripheral anemia. Furthermore, reverse transcription polymerase chain reaction (RT-PCR) analysis of colonic mass tissues showed a potent inhibitory effect in both Wnt/β-catenin signaling and YAP/TAZ signaling in the lovastatin treatment group. The results of our transcriptomic analyses in RKO indicated that lovastatin regulated several proliferation-related signaling pathways. Moreover, lovastatin suppressed important genes and proteins related to the canonical Wnt/β-catenin and alternative Wnt-YAP/TAZ signaling pathways in RKO and SW480 cells, and these effects were rescued by mevalonic acid (MVA), as confirmed through a series of Western blotting, RT-PCR, and reporter assays. Given that statins suppress oncogenic processes primarily through the inhibition of Rho GTPase in the mevalonate pathway, we speculate that lovastatin can inhibit certain Rho GTPases to suppress both canonical Wnt/β-catenin signaling and alternative Wnt-YAP/TAZ signaling. In RKO cells, lovastatin showed similar inhibitory properties as the RhoA inhibitor CCG1423, being able to inhibit β-catenin, TAZ, and p-LATS1 protein activity. Our results revealed that lovastatin inhibited RhoA activity, thereby suppressing the downstream canonical Wnt/β-catenin and alternative Wnt-YAP/TAZ pathways in colon cancer cells. These inhibitory properties suggest the promise of statins as a treatment for CRC. Altogether, the present findings support the potential clinical use of statins in non-cardiovascular contexts and highlight novel targets for anticancer treatments.

Long noncoding RNA Meg3 sponges miR-708 to inhibit intestinal tumorigenesis via SOCS3-repressed cancer stem cells growth

BackgroundColorectal cancer (CRC) remains the most common gastrointestinal cancer and a leading cause of cancer deaths worldwide, with most showing pathologies indicating the malignant transformation of early stage intestinal stem cells. The long non-coding RNA Meg3, which functions as a tumor suppressor, has been reported to be abnormal in multiple tumorigenesis events; however, the underlying mechanism by which Meg3 contributes to the malignant proliferation of colonic stem cells remains unclear.MethodsWe analyzed the expression levels of Meg3, miR-708, and SOCS3 in samples from Apc loss-of-function (Apcmin) mice and patients with CRC, particularly in colonic crypt cells. Apcmin mice and AMO/DSS-induced mice model (in vivo) and organoid culture system (in vitro) were used to explore the effect of the Meg3/miR-708/SOCS3 axis on tumorigenesis in the colon. In vitro, we performed RNApull-down, RNA immunoprecipitation, and luciferase reporter assays using DLD1 and RKO cell lines.FindingsThe Meg3/miR-708/SOCS3 signaling axis plays a critical role in the early stage of CRC development. Our data showed Meg3 levels negatively correlate with miR-708 levels both in clinical samples and in the Apcmin mouse model, which indicated that Meg3 acts as a competitive endogenous RNA (ceRNA) of miR-708. Then, miR-708 served as an oncogene, inducing neoplasia in both Apcmin mice and cultured colonic organoids. Put together, miR-708 appears to promote malignant proliferation of colonic stem cells by targeting SOCS3/STAT3 signaling.InterpretationThese data revealed that Meg3 sponges miR-708 to inhibit CRC development via SOCS3-mediated repression of the malignant proliferation of colonic stem cells. The Meg3/miR-708/SOCS3 signaling axis provides potential targets for the diagnosis and treatment of CRC, particularly early stage CRC.