Early-stage Colorectal Cancer Research Articles

Protein expression of the amino acid transporter SLC7A5 in tumor tissue is prognostic in early-stage colorectal cancer

Proteins overexpressed in early-stage cancers may serve as early diagnosis and prognosis markers as well as targets for cancer therapies. In this study, we examined the expression of an essential amino acid carrier SLC7A5 (LAT1, CD98, or 4F2 light chain) in cancer tissue from two well-annotated cohorts of 575 cases of early-stage and 106 cases of late-stage colorectal cancer patients. Immunohistochemistry showed SLC7A5 overexpression in 72.0% of early-stage and 56.6% of late-stage cases. SLC7A5 expression was not influenced by patient gender, age, location, or mismatch repair status, although it appeared to be slightly less prevalent in tumors of mucinous differentiation or with lymphovascular invasion. Statistical analyses revealed a positive correlation between SLC7A5 overexpression and both overall survival and disease-free survival in early-stage but not late-stage cancers. Co-expression analyses of the TCGA and CPTAC colorectal cancer cohorts identified a network of gene transcripts positively related to SLC7A5, with its heterodimer partner SLC3A2 having the highest co-expression score. Network analysis uncovered the SLC7A network to be significantly associated with ncRNA such as tRNA processing and the mitotic cell cycle. Since SLC7A5 is also a marker of activated lymphocytes such as NK, T, and B lymphocytes, SLC7A5 overexpression in early colorectal cancers might trigger a strong anti-tumor immune response which could results in better clinical outcome. Overall, our study provides clear evidence of differential SLC7A5 expression and its prognostic value for early-stage colorectal cancer, although the understanding of its functions in colorectal tumorigenesis and cancer immunity is currently rather limited and awaits further characterization.

GI genius endoscopy module: a clinical profile

ABSTRACT Introduction The identification of early-stage colorectal cancers (CRC) and the resection of pre-cancerous neoplastic lesions through colonoscopy allows to decrease both CRC incidence and mortality. However, colonoscopy miss rates up to 26% for adenomas and 9% for advanced adenomas have been reported. In recent years, artificial intelligence (AI) systems have been emerging as easy-to-use tools, potentially lowering the risk of missing lesions. Areas covered This review paper focuses on GI Genius device (Medtronic Co. Minneapolis, MN, U.S.A.) a computer-assisted tool designed to assist endoscopists during standard white-light colonoscopies in detecting mucosal lesions. Expert opinion Randomized controlled trials (RCTs) indicate that GI Genius is a safe and effective tool for improving adenoma detection, especially in CRC screening and surveillance colonoscopies. However, its impact seems to be less significant among experienced endoscopists and in real-world clinical scenarios compared to the controlled conditions of RCTs. Furthermore, the contribution of GI Genius appears to be mainly related to detection of non-advanced, diminutive polyps, while it doesn’t seem to affect the identification of advanced and difficult-to-detect adenomas. When using GI Genius, there were no documented side-events, with only a small number of studies reporting an increased withdrawal time or an increased removal of non-neoplastic lesions.

Clinical significance of combined tumour-infiltrating lymphocytes and microsatellite instability status in colorectal cancer: a systematic review and network meta-analysis.

Microsatellite instability (MSI) status and tumour-infiltrating lymphocytes (TIL) are established prognostic factors in colorectal cancer. Previous studies evaluating the combination of TIL and MSI status identified distinct colorectal cancer subtypes with unique prognostic associations. However, these studies were often limited by sample size, particularly for MSI-high (MSI-H) tumours, and there is no comprehensive summary of the available evidence. We aimed to review the literature to compare the survival outcomes associated with the subtypes derived from the integrated MSI-TIL classification in patients with colorectal cancer. In this systematic review and network meta-analysis, we searched PubMed, Embase, Scopus, and the Cochrane Library without language restrictions, for articles published between Jan 1, 1990, and March 13, 2024. Patient cohorts comparing different combinations of TIL (high or low) and MSI status (MSI or microsatellite stable [MSS]) in patients with surgically resected colorectal cancer were included. Studies were excluded if they focused on neoadjuvant therapy or on other immune markers such as B cells or macrophages. Methodological quality assessment was done with the Newcastle-Ottawa scale; data appraisal and extraction was done independently by two reviewers. Summary estimates were extracted from published reports. The primary outcomes were overall survival, disease-free survival, and cancer-specific survival. A frequentist network meta-analysis was done to compare hazard ratios (HRs) and 95% CI for each outcome. The MSI-TIL subgroups were prognostically ranked based on P-score, bias, magnitude, and precision of associations with each outcome. The protocol is registered with PROSPERO (CRD42023461108). Of 302 studies initially identified, 21 studies (comprising 14 028 patients) were included in the systematic review and 19 (13 029 patients) in the meta-analysis. Nine studies were identified with a low risk of bias and the remaining ten had a moderate risk of bias. The MSI-TIL-high (MSI-TIL-H) subtype exhibited longer overall survival (HR 0·45, 95% CI 0·34-0·61; I2=77·7%), disease-free survival (0·43, 0·32-0·58; I2=61·6%), and cancer-specific survival (0·53, 0·43-0·66; I2=0%), followed by the MSS-TIL-H subtype for overall survival (HR 0·53, 0·41-0·69; I2=77·7%), disease-free survival (0·52, 0·41-0·64; I2=61·6%), and cancer-specific survival (0·55, 0·47-0·64; I2=0%) than did patients with MSS-TIL-low tumours (MSS-TIL-L). Patients with the MSI-TIL-L subtype had similar overall survival (0·88, 0·66-1·18; I2=77·7%) and disease-free survival (0·93, 0·69-1·26; I2=61·6%), but a modestly longer cancer-specific survival (0·72, 0·57-0·90; I2=0%) than did the MSS-TIL-L subtype. Results from the direct and indirect evidence were strongly congruous. The findings from this network meta-analysis suggest that better survival was only observed among patients with TIL-H colorectal cancer, regardless of MSI or MSS status. The integrated MSI-TIL classification should be further explored as a predictive tool for clinical decision-making in early-stage colorectal cancer. German Research Council (HO 5117/2-2).

PREHABILITATION BEFORE GASTROINTESTINAL CANCER SURGERY (PREHAB-GI): AN IMPLEMENTATION STUDY

BACKGROUND Surgery continues to be the primary treatment option for early-stage colorectal and upper gastrointestinal (UGI) cancers. However, up to 30-40% will experience a major complication. Prehabilitation aims to improve preoperative functional reserves through physical, nutritional, and/or psychological interventions. We aimed to evaluate the implementation of a multimodal prehabilitation program in gastrointestinal cancer surgery patients. METHODS A single-arm implementation study using a pre-post design. Colorectal or UGI cancer patients scheduled for curative intent surgery at Concord Hospital with ≥14 days pre-surgery were recruited. The intervention was face-to-face or by telehealth (COVID adaptations): a 2-4-week program consisting of i) supervised exercise, ii) dietary education and protein supplements, iii) nursing support. The primary outcome was implementation using the RE-AIM (Reach/Effectiveness/Adoption/Implementation/Maintenance) framework. Secondary outcomes included functional, nutritional, and surgical outcomes. RESULTS Over 16 months, 181 were screened; 95 (52%) were eligible. Reach: 77/95 recruited (64 colorectal, 13 UGI). The median age was 70 years; 46 (60%) were males. Median intervention duration was 16 days. Effectiveness: Functional capacity using the 6-minute walk test and 2-minute step test improved from baseline to pre-surgery; 9.3m (p=0.038) and 6.5 steps (p=<0.001), respectively. Self-reported moderate, vigorous and resistance training statistically increased from baseline to pre-surgery. Hospital length of stay decreased by 1.9 days (p=0.010). There was no difference in total complications and readmissions. Adoption: 91% of referrals were directly from surgeons. Implementation: 72 completed the intervention; 5 withdrew after baseline assessment. 34% of assessments and intervention were delivered by telehealth. Adherence to the intervention was high; 94% exercise, 97% nutrition, 98% nursing. Overall, participant and clinician satisfaction was high. Maintenance: The program has been adopted as standard care with modifications post-study completion. CONCLUSIONS Our study shows that multimodal prehabilitation can be successfully implemented in a real-world setting, with a trend to improve functional and surgical outcomes.

Outcomes in colorectal endoscopic submucosal dissection for large protruded lesions: A retrospective multicenter study

Background and study aims: Colorectal endoscopic submucosal dissection (ESD) is increasingly used for treating early-stage colorectal cancer, including large, protruded lesions (LPL). However, the challenges posed by LPLs, especially those accompanied by severe fibrosis or muscle-retracting sign (MRS), remain unclear. This study aims to investigate ESD outcomes for LPL, focusing on factors such as tumor size and, submucosal fibrosis. Patients and methods: In a multicenter retrospective study (June 2012 to May 2023), data from 526 patients with 542 LPL lesions (≥ 2 cm) were analyzed. Parameters included lesion size, procedure time, dissection speed, physician experience, submucosal fibrosis, and adverse events. The tunnel method, including the double tunnel method, was used for cases with severe fibrosis or MRS. Multivariate analysis assessed factors affecting procedure difficulty, particularly LPLs ≥ 4 cm. Results: The study revealed an impressive en bloc resection rate of 97.8% and a curative resection rate of 78.6% for LPLs. Notably, fibrosis and MRS were present in 25% and 18% of 4-cm LPLs, respectively, and their frequency tended to increase as the tumor diameter increased. One treatment strategy for LPLs was the tunneling method, which was used most frequently (41 cases, 7.6%). Factors affecting dissection speed included larger tumor size, submucosal fibrosis, MRS, and physician experience. Conclusions: Treating LPLs through colorectal ESD presents significant challenges, especially in patients with fibrosis and MRS. This study highlights the importance of recognizing these complexities, and that more reliable resection strategy must be established for accurate pathological evaluation.

Demographic and clinical characteristics associated with advanced stage colorectal cancer: a registry-based cohort study in Saudi Arabia

BackgroundIn Saudi Arabia, approximately one-third of colorectal cancer (CRC) patients are diagnosed at an advanced stage. Late diagnosis is often associated with a worse prognosis. Understanding the risk factors for late-stage presentation of CRC is crucial for developing targeted interventions enabling earlier detection and improved patient outcomes.MethodsWe conducted a retrospective cohort study on 17,541 CRC patients from the Saudi Cancer Registry (1997–2017). We defined distant CRCs as late-stage and localized and regional CRCs as early-stage. To assess risk factors for late-stage CRC, we first used multivariable logistic regression, then developed a decision tree to segment regions by late-stage CRC risk, and finally used stratified logistic regression models to examine geographical and sex variations in risk factors.ResultsOf all cases, 29% had a late-stage diagnosis, and 71% had early-stage CRC. Young (< 50 years) and unmarried women had an increased risk of late-stage CRC, overall and in some regions. Regional risk variations by sex were observed. Sex-related differences in late-stage rectosigmoid cancer risk were observed in specific regions but not in the overall population. Patients diagnosed after 2001 had increased risks of late-stage presentation.ConclusionOur study identified risk factors for late-stage CRC that can guide targeted early detection efforts. Further research is warranted to fully understand these relationships and develop and evaluate effective prevention strategies.

Oat Beta-Glucan as a Metabolic Regulator in Early Stage of Colorectal Cancer-A Model Study on Azoxymethane-Treated Rats.

Factors that reduce the risk of developing colorectal cancer include biologically active substances. In our previous research, we demonstrated the anti-inflammatory, immunomodulatory, and antioxidant effects of oat beta-glucans in gastrointestinal disease models. The aim of this study was to investigate the effect of an 8-week consumption of a diet supplemented with low-molar-mass oat beta-glucan in two doses on the antioxidant potential, inflammatory parameters, and colonic metabolomic profile in azoxymethane(AOM)-induced early-stage colorectal cancer in the large intestine wall of rats. The results showed a statistically significant effect of AOM leading to the development of neoplastic changes in the colon. Consumption of beta-glucans induced changes in colonic antioxidant potential parameters, including an increase in total antioxidant status, a decrease in the superoxide dismutase (SOD) activity, and a reduction in thiobarbituric acid reactive substance (TBARS) concentration. In addition, beta-glucans decreased the levels of pro-inflammatory interleukins (IL-1α, IL-1β, IL-12) and C-reactive protein (CRP) while increasing the concentration of IL-10. Metabolomic studies confirmed the efficacy of oat beta-glucans in the AOM-induced early-stage colon cancer model by increasing the levels of metabolites involved in metabolic pathways, such as amino acids, purine, biotin, and folate. In conclusion, these results suggest a wide range of mechanisms involved in altering colonic metabolism during the early stage of carcinogenesis and a strong influence of low-molar-mass oat beta-glucan, administered as dietary supplement, in modulating these mechanisms.

Interleukin-6-Positive Immune Cells as a Possible New Immunologic Marker Associated With the Colorectal Cancer Prognosis.

Chronic inflammation creates tumor microenvironment (TME) that facilitates colorectal cancer (CRC) cell proliferation, migration, metastasis, and tumor progression. Interleukin-6 (IL-6) is a proinflammatory cytokine with a pleiotropic effect on CRC development. We aimed to evaluate IL-6 expression in tumor cells and in immune cells in TME, to assess the serum level and IL6 -174 G/C genotype distribution and to correlate the results with selected morphologic and clinical parameters that may add useful information in understanding the mechanisms of human CRC progression. A total of 153 patients with CRC were recruited in the current study. We assessed the IL-6 serum concentration through the ELISA method, the expression of IL-6 in tumor and in immune cells by immunohistochemical and double immunofluorescence staining, the MSI status by immunоhistochemistry for 4 mismatch repair (MMR) proteins, and the genotype distributions for IL6 -174G/C (rs1800795) single-nucleotide polymorphism through PCR-RFLP method. Our results showed that serum IL-6 level were increased in CRC patients as compared with healthy controls (P<0.0001), and in patients with cancers with advanced histologic type (type IV). However, the higher concentration (above the median of 55.71pg/mL) was with borderline association with longer survival of the patients after surgical therapy (P=0.055, Log rank test). We also found that IL-6+ immune cells prevailed in the invasive front (IF) of tumors compared with the tumor stroma (TS) (P<0.0001). More IL-6+ cells were recruited in the tumors with less advanced histologic type (I+II), with stronger inflammatory infiltrate in the IF, in early pTNM stages (I+II), without lymph node and distant metastases and the higher levels of IL-6+ cells, especially in the IF, were associated with longer survival (P=0.012). The results of our study suggest that although the serum levels of IL-6 are higher in CRC, the increased IL-6+ cells in tumor microenvironment, both in the invasive front and in tumor stroma, as well as the higher serum levels are associated with good prognostic variables and longer survival of the patients mainly in the early stages of CRC.

Multiple-matrix metabolomics analysis for the distinct detection of colorectal cancer and adenoma.

Although colorectal cancer (CRC) is the leading cause of cancer-related morbidity and mortality, current diagnostic tests for early-stage CRC and colorectal adenoma (CRA) are suboptimal. Therefore, there is an urgent need to explore less invasive screening procedures for CRC and CRA diagnosis. Untargeted gas chromatography-mass spectrometry (GC-MS) metabolic profiling approach was applied to identify candidate metabolites. We performed metabolomics profiling on plasma samples from 412 subjects including 200 CRC patients, 160 CRA patients and 52 normal controls (NC). Among these patients, 45 CRC patients, 152 CRA patients and 50 normal controls had their fecal samples tested simultaneously. Differential metabolites were screened in the adenoma-carcinoma sequence. Three diagnostic models were further developed to identify cancer group, cancer stage, and cancer microsatellite status using those significant metabolites. The three-metabolite-only classifiers used to distinguish the cancer group always keeps the area under the receiver operating characteristic curve (AUC) greater than 0.7. The AUC performance of the classifiers applied to discriminate CRC stage is generally greater than 0.8, and the classifiers used to distinguish microsatellite status of CRC is greater than 0.9. This finding highlights potential early-driver metabolites in CRA and early-stage CRC. We also find potential metabolic markers for discriminating the microsatellite state of CRC. Our study and diagnostic model have potential applications for non-invasive CRC and CRA detection.

Intestinal Bacteria Fluctuating in Early-Stage Colorectal Cancer Carcinogenesis are Associated with Diet in Healthy Adults

This hospital-based, cross-sectional study aimed to explore the association between diet and fluctuating intestinal bacteria in early-stage colorectal cancer (CRC) (Atopobium parvulum, Actinomyces odontolyticus, Solobacterium moorei, and Bifidobacterium longum). Healthy participants (n = 212) who underwent total colonoscopy at National Cancer Center Hospital (Tokyo, Japan) were divided into two groups according to the relative abundance of bacteria in their feces: those in the top 25% of relative bacterial abundance as cases and the bottom 25% as controls. The participants were divided into three groups (low, medium, and high) according to their intake of food groups associated with CRC. Multivariable logistic regression analysis was conducted to estimate the association between dietary intake and higher relative abundance of bacteria. Dairy products were inversely associated with a higher relative abundance of A. parvulum, A. odontolyticus, and S. moorei, with odds ratios (high vs. low) and 95% confidence interval as follows: 0.16 (0.06–0.44), 0.25 (0.08–0.82), and 0.29 (0.11–0.78), respectively. Additionally, dietary fiber was inversely associated with a higher relative abundance of S.moorei (0.29 [0.11–0.78]). No association was observed between diet and B.longum. In conclusion, healthy adults with a higher intake of dairy products and fiber had lower odds of having a higher relative abundance of CRC-associated microbiota.

Consumption of Feed Supplemented with Oat Beta-Glucan as a Chemopreventive Agent against Colon Cancerogenesis in Rats

Colorectal cancer (CRC) accounts for 30% of all cancer cases worldwide and is the second leading cause of cancer-related deaths. CRC develops over a long period of time, and in the early stages, pathological changes can be mitigated through nutritional interventions using bioactive plant compounds. Our study aims to determine the effect of highly purified oat beta-glucan on an animal CRC model. The study was performed on forty-five male Sprague–Dawley rats with azoxymethane-induced early-stage CRC, which consumed feed containing 1% or 3% low molar mass oat beta-glucan (OBG) for 8 weeks. In the large intestine, morphological changes, CRC signaling pathway genes (RT-PCR), and proteins (Western blot, immunohistochemistry) expression were analyzed. Whole blood hematology and blood redox status were also performed. Results indicated that the histologically confirmed CRC condition led to a downregulation of the WNT/β-catenin pathway, along with alterations in oncogenic and tumor suppressor gene expression. However, OBG significantly modulated these effects, with the 3% OBG showing a more pronounced impact. Furthermore, CRC rats exhibited elevated levels of oxidative stress and antioxidant enzyme activity in the blood, along with decreased white blood cell and lymphocyte counts. Consumption of OBG at any dose normalized these parameters. The minimal effect of OBG in the physiological intestine and the high activity in the pathological condition suggest that OBG is both safe and effective in early-stage CRC.

Review of Animal Models of Colorectal Cancer in Different Carcinogenesis Pathways.

Colorectal cancer (CRC) is a common malignant tumor of the gastrointestinal tract with increasing morbidity and mortality. Exploring the factors affecting colorectal carcinogenesis and controlling its occurrence at its root is as important as studying post-cancer treatment and management. Establishing ideal animal models of CRC is crucial, which can occur through various pathways, such as adenoma-carcinoma sequence, inflammation-induced carcinogenesis, serrated polyp pathway and de-novo pathway. This article aims to categorize the existing well-established CRC animal models based on different carcinogenesis pathways, and to describe their mechanisms, methods, advantages and limitations using domestic and international literature sources. This will provide suggestions for the selection of animal models in early-stage CRC research.

Abstract 295: Fibroblast-specific endoglin deletion alters colonic immune infiltrate in premalignant colorectal lesions

Abstract Background: Endoglin expression on cancer-associated fibroblasts has been reported to promote tumor growth and metastasis, especially in colorectal cancer (CRC). However, little research has been done on the function of endoglin-expressing fibroblasts in the early stages of CRC and how it interacts with the host immune system. Here, we investigated the role of endoglin expression on fibroblasts during intestinal inflammation and tumorigenesis in a chemically induced colitis-associated CRC model. Methods: We generated two inducible fibroblast-specific endoglin (ENG) knockout mice Collagen1a1 CreERT2.ENGfl/fl (ENGCol1a1-/−) and Collagen1a2-CreERT.ENGfl/fl (ENGCol1a2-/−). Cre-mediated recombination in mice was induced by oral administration of tamoxifen for three consecutive days. Polyp formation was induced by a single injection of azoxymethane (AOM), followed by three cycles of dextran sodium sulphate (DSS). Analysis of the immune cell composition in the colons and polyps was done using flow cytometry. Hematoxylin and eosin (H&amp;E) staining was performed to evaluate intestinal inflammation. Results: ENGCol1a1-/− mice showed a considerably higher number of colonic lesions than non-induced controls, whereas in the ENGCol1a2-/−, surprisingly no significant difference in the number of lesions was observed. Flow cytometry analysis revealed, compared to controls, the lesions of ENGCol1a1-/− mice had a significant increase in F4/80+ Ly6C− macrophages and Ly6G+ neutrophils, while those of ENGCol1a2-/− mice had a marked decrease in CD11C+ dendritic cells. Given the changes in immune cell infiltration, we also assessed acute inflammation, using a short-term DSS experiment. Interestingly, ENGCol1a1-/− mice lost significantly more weight compared to controls, indicating increased inflammation. Although weight loss did not differ in Col1a2 mice between the two groups, ENGCol1a2-/− mice had a much lower H&amp;E staining score, indicating less colonic damage and inflammation. Furthermore, a decrease in F4/80+ Ly6C− macrophages was observed in the colons of both ENGCol1a1-/- and ENGCol1a2-/− mice, despite no change in the overall CD45+ immune cell population. Notably, the number of Ly6G+ neutrophils was decreased in the colons of ENGCol1a1-/− mice but increased in ENGCol1a2-/− mice. In addition, a decrease in CD11C+ dendritic cells was seen in the colons ENGCol1a2-/− mice. Conclusion: Our results suggest that AOM/DSS-induced polyp formation and infiltrating immune cells differ in ENGCol1a1-/− and ENGCol1a2-/− mice. Fibroblast-specific deletion of endoglin can reduce macrophage and dendritic cell infiltration, colonic damage, and protect mice from DSS colitis. Citation Format: Subinuer Abudukelimu, Mark J. Schoonderwoerd, Madelon Paauwe, Eveline S. de Jonge-Muller, Stef G. Janson, Nadine van Montfoort, Lukas JAC Hawinkels. Fibroblast-specific endoglin deletion alters colonic immune infiltrate in premalignant colorectal lesions [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 295.

Abstract 758: Comparative Microbiome Analysis of Paired Mucosal and Fecal Samples in Korean Colorectal Cancer Patients

Abstract Background Beyond the known risk factors such as age over 50, unhealthy diet, ethnicity, and smoking, emerging evidence suggests that gut microbial dysbiosis plays a crucial role in the early stages of colorectal cancer (CRC) by contributing to chronic inflammation and various intestinal dysfunctions. Even though various bacterial species have been studied, the gut microbiome profile as a representative biomarker in CRC patients remains largely unreported. This study presents a comparative analysis of the microbiome profiles of fecal and mucosal samples from CRC patients, followed by metagenomic profiling investigation to validate dominant bacteria in each sample type of CRC patients. Methods The study involved 12 patients receiving CRC resection at Myongji Hospital in South Korea, recruited from May 2020 to June 2021. Fecal samples were collected pre-surgery, and mucosal samples during surgery. Paired-end sequencing was performed using Illumina MiSeq (Illumina, San Diego, USA) platform. 16s rRNA gene-based microbiome profiling was analyzed using QIIME2 (V.2020.11), a plugin-based platform for microbiome analysis. Sequencing reads were filtered, denoised, and clustered into amplicon sequence variants (ASVs) using DADA2 included in QIIME2. Taxonomic classification was assigned in the QIIME2 pipeline using a pre-trained classifier based on the Silva 138.1 reference sequence. Linear discriminant analysis (LDA) effect size (LEfSe) analysis was performed with LDA score ≥3.0 and p-value of 0.05. Results The study subjects included 12 Korean patients, with an average age of 71 ± 10 years. The gender distribution included 3 men and 9 women whose body mass index was 24.6 ± 2.4 (mean ± SD). There was significant difference observed in UniFrac beta-diversity between the two groups (p=0.001). The relative taxonomic patterns of the microbiota between CRC stool and tissue showed that Bacteroides and Fusobacterium were more dominant in tissue than stool at both phylum and genus levels. Further taxonomic differences between the samples revealed that Firmicutes, Bacilli, and Lactobacillacease were over-represented in CRC patient stool, while Pseudomonadales (p&amp;lt;0.001) and Pseudomonas (p&amp;lt;0.001) were identified in the mucosal tissue. Conclusion Our findings revealed that notable distinction was observed in the beta-diversity, indicating a unique microbial composition in tissue. Specifically, higher prevalence of Bacteroides and Fusobacterium at the genus level were identified in tissue. Additionally, our analysis highlighted Pseudomonadales and Pseudomonas emerged in CRC mucosal tissues. Furthermore, by comparing with a healthy control group, we aim to further elucidate potential markers unique to CRC patients. Citation Format: Sanghun Lee. Comparative Microbiome Analysis of Paired Mucosal and Fecal Samples in Korean Colorectal Cancer Patients [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 758.

Abstract 5533: The difference of immune microenvironment betweende novometastatic and non-metastatic microsatellite instability-high colorectal cancer

Abstract Introduction: Microsatellite instability-high (MSI-H) colorectal cancer (CRC) consists of 15% of all CRC but only 2-4% of metastatic CRC. The favorable prognosis of non-metastatic (early-stage) MSI-H CRC may be related to vigorous immune reaction in tumor microenvironment. However, the mechanisms of immune evasion in metastatic (late stage) MSI-H CRC are largely unknown. Materials and Methods: We retrospectively collected patients with MSI-H CRC from National Taiwan University Hospital and Kaohsiung Chang Gung Memorial Hospital. The archival tumor specimens were used for immune cells analysis by Nanostring PanCancer Immune Panel, and spatial immune characterization by multiplex immunofluorescence stains. Only surgical resected primary tumors and metastatic tumors were included. Gene expression and immune cells composition were compared between non-metastatic and de novo metastatic tumors. Results: We enrolled 59 and 27 patients with early-stage and late-stage MSI-H CRC, respectively. Twelve metastatic site tumors were also collected. The clinicopathologic characteristics between patients who have early- and late-stage MSI-H CRC were not significantly different. There are heterogeneous immune cell compositions in these 98 MSI-H tumors. Compared to early-stage MSI-H tumors, there are significantly fewer cytotoxic (difference -0.497, p = 0.001) and dendritic cells (difference -0.528, p = 0.021) in late-stage MSI-H tumors. Gene set enrichment analysis disclosed significantly decrease in the expression of JAK-STAT-IFN-γ- and antigen processing-related pathways in late-stage MSI-H tumors. The top 5 genes with significantly differential expression between late-stage and early-stage tumors are C7, TNFRSF12A, MFGE8(up-regulated) and CXCL5, IFNL1, GZMH, HMGB1 and CXCR1 (down-regulated). Conclusions: There are significantly fewer cytotoxic and dendritic cells in late-stage MSI-H CRC, compared to early-stage MSI-H CRC, which is associated with decrease expression in JAK-STAT-IFN-γ- and antigen processing-related pathways. Citation Format: Kuo-Hsing Chen, Chia-Lang u Hs, Yu-Li Su, Chang-Tsu Yuan, Jia-Huei Tsai, Yi-Hsin Liang, Ann-Lii Cheng, Kun-Huei Yeh. The difference of immune microenvironment betweende novometastatic and non-metastatic microsatellite instability-high colorectal cancer [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 5533.

Abstract 7294: CREATE-2: Colorectal cancer &amp; adenoma test evaluation of a multi-omic blood test

Abstract Background: Colorectal cancer (CRC) is the third most common cancer worldwide, with almost 2 million new cases reported in 2020. CRC develops over time from a pre-cancerous stage (adenoma) - the ‘adenoma-carcinoma sequence’. Pre-cancerous lesions, such as Higher Risk Adenomas (HRA), harbour an increased risk of developing into CRC and their features are defined according to size, number and histological features. Screening for signs of CRC is recommended for average-risk adults using faecal immunochemical testing (FIT) in the UK, to enable the removal of pre-cancerous lesions and treatment of early-stage cancers. However, the performance of FIT is limited. Approximately 10% of CRC diagnoses have a negative FIT result, and it currently has ~93% false positive rate. Moreover, the sensitivity for detecting AA is only 24%, highlighting the need for alternative strategies. Methods: A promising strategy for earlier CRC detection is the clinical use of Fourier transform infrared (FTIR) spectroscopy. The Dxcover® Colorectal Cancer Liquid Biopsy is a rapid multi-omic test that interrogates a blood sample with infrared (IR) radiation and produces a distinctive signature that represents the whole biomolecular profile of the sample. Rather than focusing on individual biomarkers, the technique encompasses the full range of diagnostic information from both the tumor and the non-tumor response. In the initial CREATE (ColoREctal Cancer &amp; Adenoma Test Evaluation) feasibility study, the potential of the technology was highlighted in a retrospective cohort of patients comprising 100 CRC, 92 adenoma samples and 104 colonoscopy screening controls diagnosed as non-cancer. At 90% specificity, the test reported 80% CRC sensitivity and 59% HRA sensitivity. CREATE-2 is a prospective, observational, multicenter study, currently recruiting patients across the United States. The primary objective of the study is to determine the diagnostic accuracy of the blood-based Dxcover Colorectal Cancer Liquid Biopsy for CRC and HRA, and collectively as advanced colorectal neoplasia. Primary outcomes are sensitivity, specificity, negative predictive value, and positive predictive value of the test as compared to the standard of care screening modality. The study population is comprised of patients aged 45-84 considered ‘average-risk’ for CRC, undergoing routine CRC screening as standard of care. Patients are treatment naïve for CRC/HRA and must be willing to consent to blood draw pre-bowel preparation, and follow-up for 24 months. A rapid blood test that is sensitive to pre-cancerous lesions and early-stage CRC could substantially improve patient outcomes. Current screening programs have addressable shortcomings, and the emergence of new technologies is essential to support earlier CRC detection. Citation Format: James M. Cameron, Georgios Antoniou, Rose McHardy, David Palmer, Alexandra Sala, Matthew Baker. CREATE-2: Colorectal cancer &amp; adenoma test evaluation of a multi-omic blood test [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 7294.

Abstract 2566: Molecular characteristic profile in early colorectal cancer with V600E and non-V600E BRAF mutations

Abstract Background: The BRAF V600E mutation in colorectal cancer (CRC) is a significant indicator of poor prognosis, especially in tumors exhibiting microsatellite instability (MSI). It is more common on the right side of the colon but can occur anywhere within the colon. Although other BRAF mutations existed, current research primarily focused on BRAF V600E. Most clinical data sets were centered on advanced colorectal cancer. There was limited understanding of the molecular characteristics of early-stage colorectal cancer patients with BRAF mutations, which impacted postoperative prognosis management, including refining adjuvant therapy regimens. Therefore, we analyzed the molecular characteristics of early-stage CRC surgical patients. Methods: Tumor tissue from 767 early-stage CRC patients diagnosed between 2021 to 2022 in China were analyzed using NGS (panel on 733 gene) to validate the mutation characteristics. Tumor specimens were tested for the BRAF mutation and MSI status. Result: Among 767 early CRC cases tested, BRAF mutations accounted for 6.52% (50/767), with 62% (31/50) being BRAF V600E, followed by 14% (7/50) for BRAF D594G. Notably, there were two cases of fusion variations, TRIM24-BRAF, and one case of BRAF copy gain. Among the BRAF mutation population, 11 cases were MSI-H, with 8 of them being BRAF V600E/MSI-H. Only one MSH-H patient had a germline mutation in the MLH1 gene, with a concurrent mutation in BRAF K601T.Interestingly, when comparing the mutation profiles of the BRAF V600E population with those of the non-V600E BRAF mutation population, we found distinct co-mutated genes despite both being BRAF mutations. In the BRAF V600E group, the top three frequently mutated genes were TP53 (52%), RNF43 (32%), and SMAD4 (32%). Additionally, the BRAF V600E/MSI-H subgroup presented a distinct mutation profile, with minimal occurrences of TP53 and SMAD4 mutations. In the non-V600E BRAF mutation group, the top three frequently mutated genes were TP53 (84%), APC (63%), and KRAS (32%). Conclusions: In examining the mutation profile characteristics of early colorectal cancer with BRAF mutations, the proportion of BRAF V600E/MSI-H appeared to have been lower than that reported in advanced cases. Furthermore, in terms of the frequency of co-mutated genes, it seemed that BRAF V600E had exhibited a higher malignant driving mutation effect as a single gene, while non-V600E mutations had required more cooperative tumor suppressor genes or oncogenes. Analyzing the molecular characteristics of early colorectal cancer patients with V600E and non-V600E BRAF mutations could help improve postoperative management and further our understanding of tumor progression. Citation Format: Zhang Quan An. Molecular characteristic profile in early colorectal cancer with V600E and non-V600E BRAF mutations [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 2566.

Abstract 1385: Crosstalk between hepatocyte and myeloid-specific IL17 signaling in colorectal cancer metastasis

Abstract Advanced colorectal cancer (CRC) is resistant to current immunotherapies and prone to metastasis. Chronic inflammation mediated by cytokines such as interleukin (IL)17 activates the oncogenic pathways in cancer cells, promoting sporadic and inflammation-associated CRC. Increased levels of IL17A in early stages of CRC portends poor prognosis indicating its potential involvement into metastasis. We and others previously showed that IL17A signaling is required for early CRC tumorigenicity in a variety of models and that in early CRC, its ability to signal to epithelial cells is essential. What remains unknown is whether IL17 signaling to other cell types within the tumor microenvironment (TME) is essential to control tumor progression and metastasis. Using a model of colitis-associated cancer (CAC) we found that “late” IL17A neutralization decreases tumor burden, possibly acting through regulation of myeloid cells and chemokine network essential for the control of immunosuppressive TME. Next, using models of colorectal cancer liver metastasis (CRLM) including intraportal cell injection and cecum transplantation of organoids with distinct set of oncogenic mutation we found that IL17 neutralization reduces metastasis. FACS analysis revealed that IL17A promotes the recruitment of tumor-associated macrophages and other key myeloid subsets into the metastatic liver environment. Interestingly, ablation of IL17RC (receptor) in myeloid cells only (using Il17rcf/f -LysMCre mice) led to reduction in metastasis and reshaping of metastatic myeloid cell compartments. Meanwhile, IL17 signaling in hepatocytes was required for early metastasis and pre-metastatic niche formation, as the ablation of IL17RC in hepatocytes (using Il17rcf/f -AlbCre mice) led to a reduction of metastatic numbers but not growth. This coincided with reduced neutrophil recruitment and enhanced activation of cytotoxic innate lymphoid cells and CD8 T lymphocytes, indicating the role of hepatocyte specific IL17 signaling in blunting anti-tumor immunity. Our findings illuminate the role of inflammatory cytokine IL17 into CRC progression and metastasis and imply its distinct cell type specific role within the metastatic liver TME. Citation Format: Katarzyna Chojnacka, Dan Kamen, Katrina M. Reyes, Hana Tomizawa, Sergei I. Grivennikov. Crosstalk between hepatocyte and myeloid-specific IL17 signaling in colorectal cancer metastasis [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 1385.

Abstract 1039: A novel serum lipidomics signature validated in a prospective multi-center trial enables accurate and low-cost CRC screening

Abstract Background: Blood-based colorectal cancer (CRC) testing is expected to increase compliance to recommended screening guidelines. However, existing methods based on cfDNA typically suffer from low performance in detecting early-stage cancer and pre-malignant advanced adenomas (AA); and from high-cost, making routine screening financially impractical. Attempts to identify other blood biomarkers suffered from low reproducibility across studies, due to confounding factors related to utilizing samples from diagnosed and potentially treated patients, and artifacts related to differential handling of cases and control samples. Method: Serum samples were obtained from the Israeli Multi-OMICS screening study (IMOSS-500K), in which ~500,000 serum samples were collected as part of standard clinical routine by Maccabi Health between July 2021 and January 2023. De-identified electronic health records were used to identify 152 primary CRC patient, diagnosed within 1 year after serum collection; and another 270 age- and gender-matched controls. The cohort was divided to train and test sub-cohorts, comprising of patients diagnosed within 2-12 and 0-2 months after sample collection, respectively. A 2nd test cohort was obtained from Rambam Hospital, included 97 samples from treatment-native CRC patients, and 24 age- and gender-matched controls. A 3rd test cohort, obtained from IMOSS-500K, included 139 patients that were diagnosed with AA within 2 months from serum collection; and 139 age- and gender-matched controls. All samples were analyzed with a proprietary high-throughput LC-MS based multi-OMICS platform detecting 10,000’s of metabolites, lipids, and protein biomarker ions per sample. A diagnosis score was defined via a logistic regression model in the train sub-cohort and the diagnostic performance for was evaluated in the 3 test cohorts. Results: We identified a novel signature for CRC based on the concentration of 4 structurally related serum lipids, whose structure was not previously reported in literature. Evaluating the performance of the score in the test sub-cohort, showed a remarkable AUC of 0.96 for the detection of CRC, with a high sensitivity of 89% at 90% specificity; with 90% sensitivity achieved already at stage I. The high diagnostic performance for detecting CRC was reproducible in the 2nd test cohort, with an AUC of 0.97, and sensitivity of 94% at 90% specificity. Analyzing the 3nd test cohort, our signature achieved a sensitivity of 37% at 90% specificity for the detection of AA. Conclusion: We developed a novel low-cost blood-lipidomics based method for CRC detection, suitable for routine screening. Comprehensive validation through a multi-center prospective study showed similar performance to that published for the stool-cfDNA test ColoGuard, and higher performance than other published blood-cfDNA methods in the detection of early-stage CRC and AA. Citation Format: Boris Sarvin, Avi Shoshan, Eldad Kepten, Mark Vernik, Ilya Podolsky, Carmel Shor, Shira Shaham-Niv, Tomer Shlomi. A novel serum lipidomics signature validated in a prospective multi-center trial enables accurate and low-cost CRC screening [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 1039.

Abstract 737: Arrays of 3D ECM-embedded fibroblast clusters for characterization of ECM remodeling by primary cancer associated fibroblasts and for evaluation of drugs attenuating fibrotic ECM remodeling

Abstract Chronic fibrosis can lead to organ failure and is also associated with cancer, where the tumor is interpreted as a chronic wound, and the fibrotic tumor environment drives disease progression. Fibrosis occurs in an inflammatory environment where macrophages are activated, and fibroblasts transdifferentiate into myofibroblasts. Activated macrophages stimulate the myofibroblasts to produce excessive amounts of collagen-rich ECM. Changes in proteolytic activity and high contractile forces that myofibroblasts apply onto their tissue environment, further lead to extensive remodeling of the healthy tissue matrix into a scar matrix. Similar activity is displayed by cancer-associated fibroblasts (CAFs) in tumors. Intervening with the excessive ECM remodeling by activated fibroblasts represents a candidate therapeutic strategy to normalize the architecture of fibrotic and malignant tissues. We developed a screening platform using an assay based on automated image guided injection of clusters of fibroblasts in wells of multi-well plates preloaded with a collagen-rich ECM network. The identical x-y-z position, spacing, and size of the ECM-embedded fibroblast clusters in each well facilitates automated real time confocal microscopy and quantitative image analysis algorithms. We use this setup for automated quantitative analysis of ECM remodeling activity of CAFs obtained from early-stage colorectal cancer patients. We find that CAFs from these early-stage lesions display increased ECM remodeling capacity as compared to patient matched normal fibroblasts. We then use the same setup to screen a series of compounds for their ability to attenuate ECM remodeling triggered by TGFb-activated primary human fibroblasts. We detect known and novel pathways, and we identify small molecule inhibitors with a promising efficacy versus toxicity profile. Lastly, we detect a previously unknown concentration-dependent side effect of ALK5 inhibitors that leads to the identification of a novel profibrotic pathway and indicates that caution is warranted for the clinical application of ALK5 inhibitors. Citation Format: Erik H. J. Danen. Arrays of 3D ECM-embedded fibroblast clusters for characterization of ECM remodeling by primary cancer associated fibroblasts and for evaluation of drugs attenuating fibrotic ECM remodeling [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 737.