Prognosis Of Colorectal Cancer Research Articles

LncRNA GAS6-AS1 contributes to 5-fluorouracil resistance in colorectal cancer by facilitating the binding of PCBP1 with MCM3

5-Fluorouracil (5-FU) resistance has always been a formidable obstacle in the adjuvant treatment of advanced colorectal cancer (CRC). In recent years, long non-coding RNAs have emerged as key regulators in various pathophysiological processes including 5-FU resistance. TRG is a postoperative pathological score of the chemotherapy effectiveness for CRC, of which TRG 0–1 is classified as chemotherapy sensitivity and TRG 3 as chemotherapy resistance. Here, RNA-seq combined with weighted gene correlation network analysis confirmed the close association of GAS6-AS1 with TRG. GAS6-AS1 expression was positively correlated with advanced clinicopathological features and poor prognosis in CRC. GAS6-AS1 increased the 50% inhibiting concentration of 5-FU, enhanced cell proliferation and accelerated G1/S transition, both with and without 5-FU, both in vitro and in vivo. Mechanistically, GAS6-AS1 enhanced the stability of MCM3 mRNA by recruiting PCBP1, consequently increasing MCM3 expression. Furthermore, PCBP1 and MCM3 counteracted the effects of GAS6-AS1 on 5-FU resistance. Notably, the PDX model indicated that combining chemotherapeutic drugs with GAS6-AS1 knockdown yielded superior outcomes in vivo. Together, our findings elucidate that GAS6-AS1 directly binds to PCBP1, enhancing MCM3 expression and thereby promoting 5-FU resistance. GAS6-AS1 may serve as a robust biomarker and potential therapeutic target for combination therapy in CRC.

Colorectal Cancer Stem Cell Biomarkers: Biological Traits and Prognostic Insights.

Due to self-renewal, differentiation, and limitless proliferation properties, Cancer Stem Cells (CSCs) increase the probability of tumor development. These cells are identified by using CSC markers, which are highly expressed proteins on the cell surface of CSCs. Recently, the therapeutic application of CSCs as novel biomarkers improved both the prognosis and diagnosis outcome of colorectal Cancer. In the present review, we focused on a specific panel of colorectal CSC markers, including LGR5, ALDH, CD166, CD133, and CD44, which offers a targeted and comprehensive analysis of their functions. The selection criteria for these markersCancer were based on their established significance in Colorectal Cancer (CRC) pathogenesis and clinical outcomes, providing novel insights into the CSC biology of CRC. Through this approach, we aim to elevate understanding and stimulate further research for developing effective diagnostic and therapeutic strategies in CRC.

A novel four‑gene biomarker for tobacco smoking -induced colorectal cancer progression.

Cigarette smoking greatly promotes the progression and poor prognosis of colorectal cancer (CRC) patients, with the molecular mechanism still not fully clear. In this study, CRC cells were exposed to tobacco specific nitrosamine 4‑(methylnitrosamino)‑1‑(3‑pyridyl) 1‑butanone (NNK), and the differentially expressed smoking-related genes were identified based on both NNK-induced CRC cells and a total of 763 CRC tissues from TCGA cohort. Cox regression analysis, ROC curve and Kaplan-Meier plot were used to establish the risk score model for CRC prognosis. Moreover, qRT-PCR, western blotting, colony formation, migration and invasion assays were performed to verify the core differentially expressed smoking-related gene and its molecular function in NNK-induced CRC progression. Results indicated NNK significantly enhanced CRC cell proliferation, migration and invasion. Moreover, a four-gene signature containing AKR1B10, CALB2, PLAC1, GNA15 was established as CRC prognosis marker. Among these four genes, AKR1B10 was further validated as the core gene, and its expression was significantly inhibited after NNK exposure in CRC cells. Results of gene enrichment analysis and western blotting suggested AKR1B10 might reduce the malignant progression of NNK-induced CRC cells through inhibiting Wnt signaling pathway by promoting E-Cadherin expression and inhibiting the expression of N-Cadherin, β-Catenin, Vimentin and Snail. In conclusion, a new four smoking-related genes can be jointly used as prognostic markers for CRC. AKR1B10 served as a tumor suppressor, can be used as a potential target to inhibit NNK-induced CRC malignant progression through regulating Wnt signaling pathway. This study demonstrates tobacco-derived NNK dependence would promote the malignant progression of colorectal cancer through regulating the expressions of AKR1B10/Wnt signaling pathway. And a novel four-gene signature is established for the prognosis prediction of smoking CRC patients. These findings have important translational implications given the continued use of tobacco and the difficulty in smoking cessation worldwide, which can be applied to alleviate the adverse effects induced by tobacco dependence on colorectal cancer patients.

High-Throughput Metabolic Pattern Screening Strategy for Early Colorectal and Gastric Cancers Based on Covalent Organic Frameworks-Assisted Laser Desorption/Ionization Mass Spectrometry.

Precise early diagnosis and staging are conducive to improving the prognosis of colorectal cancer (CRC) and gastric cancer (GC) patients. However, due to intrusive inspections and limited sensitivity, the prevailing diagnostic methods impede precisely large-scale screening. In this work, we reported a high-throughput serum metabolic patterns (SMP) screening strategy based on covalent organic frameworks-assisted laser desorption/ionization mass spectrometry (hf-COFsLDI-MS) for early diagnosis and staging of CRC and GC. Notably, 473 high-quality SMP were extracted without any tedious sample pretreatment and coupled with multiple machine learning algorithms; the area under the curve (AUC) value is 0.938 with 96.9% sensitivity for early CRC diagnosis, and the AUC value is 0.974 with 100% sensitivity for early GC diagnosis. Besides, the discrimination of CRC and GC is accomplished with an AUC value of 0.966 for the validation set. Also, the screened-out features were identified by MS/MS experiments, and 8 metabolites were identified as the biomarkers for CRC and GC. Finally, the corresponding disordered metabolic pathways were revealed, and the staging of CRC and GC was completed. This work provides an alternative high-throughput screening strategy for CRC and GC and highlights the potential of metabolic molecular diagnosis in clinical applications.

Metabolic Alteration Bridging the Prediabetic State and Colorectal Cancer

Prediabetes and colorectal cancer (CRC) represent compelling health burdens responsible for high mortality and morbidity rates, sharing several modifiable risk factors. It has been hypothesized that metabolic abnormalities linking prediabetes and CRC are hyperglycemia, hyperinsulinemia, and adipokines imbalance. The chronic stimulation related to these metabolic signatures can favor CRC onset and development, as well as negatively influence CRC prognosis. To date, the growing burden of prediabetes and CRC has generated a global interest in defining their epidemiological and molecular relationships. Therefore, a deeper knowledge of the metabolic impairment determinants is compelling to identify the pathological mechanisms promoting the onset of prediabetes and CRC. In this scenario, this review aims to provide a comprehensive overview on the metabolic alterations of prediabetes and CRC as well as an overview of recent preventive and therapeutic approaches for both diseases, focusing on the role of the metabolic state as a pivotal contributor to consider for the development of future preventive and therapeutic strategies.

Abstract LB267: Disrupting cytoplasmic proton motive force induces ferroptotic cell death in colorectal cancer: A novel anti-cancer mechanism

Abstract Introduction: Chemotherapeutic resistance and tumor recurrence remain the leading causes of poor prognosis in colorectal cancer (CRC). Herein, we evaluated the anti-cancer effect of a novel repurposed drug HLN* in CRC. Methods: The changes in membrane potential were studied using DiSC(3) fluorescence by confocal microscopy. Cytotoxic activity of compound was studied using Sulphorhodamine-B (SRB) assay. Changes in mitochondrial membrane potential were studied using JC-1 dye. ROS accumulation was analyzed using DCFDA fluorescence using FACS analysis. Ferrorange assay was used to check the ferrous ion influx within the cell. Western blot was used to identify mode of cell death enacted. Results: Our results show that HLN treatment reduced the survival of human and murine CRC cells (CT26, HCT116, Colo 205 and MC38) with IC50 ranging 1-4 µM. HLN further inhibited proton motive force (PMF) by sequentially depolarizing and hyperpolarizing the cell membrane, as examined by cellular membrane potential using DiSC(3) dye by confocal microscopy. Disruption of the PMF leads to changes in various cellular signaling cascades including ROS production and mitochondrial membrane potential (MMP) changes. The MMP was significantly reduced by HLN treatment in CRC cells. Furthermore, we also observed an increase in ROS production by HLN. Pretreatment with N-acetyl cysteine (NAC), an antioxidant, blocked the effects of HLN. Interestingly, ferroptotic cell death markers GPX4, GPX1, SLC7A11/xCT, NRF2 and KEAP1 were significantly inhibited by HLN treatment in CRC cells as observed by western blotting. Ferroptotic induction was then confirmed using ferrorange assay wherein we observed a concentration dependent increase in ferrorange intensity indicating an increase in Fe+2. Overall, HLN dissipates ΔpH by modulating iron influx leading to ferroptotic cell death through ROS. Conclusion: Taken together, our results demonstrate the anti-cancer activity of a novel repurposed drug HLN and its unique mechanism of action. Our results provide a promise for developing this drug as a potential treatment option for CRC, through a novel anti-cancer mechanism. * Due to Intellectual property issued, the name of the drug is not provided Citation Format: Shreyas R. Gaikwad, Mohamed A. Eltokhy, Morgan Moore, Keerthi Kailath, Sanjay K. Srivastava. Disrupting cytoplasmic proton motive force induces ferroptotic cell death in colorectal cancer: A novel anti-cancer mechanism [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB267.

A new clinical model for predicting lymph node metastasis in T1 colorectal cancer

PurposeLymph node metastasis (LNM) is a crucial factor that determines the prognosis of T1 colorectal cancer (CRC) patients. We aimed to develop a practical prediction model for LNM in T1 CRC.MethodsWe conducted a retrospective analysis of data from 825 patients with T1 CRC who underwent radical resection at a single center in China. All enrolled patients were randomly divided into a training set and a validation set at a ratio of 7:3 using R software. Risk factors for LNM were identified through multivariate logistic regression analyses. Subsequently, a prediction model was developed using the selected variables.ResultsThe lymph node metastasis (LNM) rate was 10.1% in the training cohort and 9.3% in the validation cohort. In the training set, risk factors for LNM in T1 CRC were identified, including depressed endoscopic gross appearance, sex, submucosal invasion combined with tumor grade (DSI-TG), lymphovascular invasion (LVI), and tumor budding. LVI emerged as the most potent predictor for LNM. The prediction model based on these factors exhibited good discrimination ability in the validation sets (AUC: 79.3%). Compared to current guidelines, the model could potentially reduce over-surgery by 48.9%. Interestingly, we observed that sex had a differential impact on LNM between early-onset and late-onset CRC patients.ConclusionsWe developed a clinical prediction model for LNM in T1 CRC using five factors that are easily accessible in clinical practice. The model has better predictive performance and practicality than the current guidelines and can assist clinicians in making treatment decisions for T1 CRC patients.

ZNF26-Associated Genes as Prognostic Signatures in Colorectal Cancer with Broad Therapeutic Implications.

The identification of biomarkers correlated with colorectal cancer (CRC) prognosis holds substantial importance from both clinical and scientific perspectives. Zinc finger protein 26 (ZNF26) has not been previously investigated or documented in solid tumors; thus, further research is necessary to ascertain its prognostic value in CRC. Gene expression profiles and clinicopathological data were acquired from The Cancer Genome Atlas (TCGA) database. Subsequently, expression correlation was assessed utilizing the TCGA CRC cohort. The prognostic value of ZNF26 was evaluated through Kaplan-Meier (KM) and ROC curve analyses. Following this, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted to perform enrichment analysis between high- and low-ZNF26 expression groups. The association between immune cells, immune checkpoint genes, and ZNF26 expression levels was examined. Lastly, the research findings were further validated using CRC tissue samples. The results revealed that, in comparison to healthy controls, CRC significantly reduced ZNF26 expression. Elevated ZNF26 expression was associated with poorer overall survival in CRC patients. Additionally, high ZNF26 expression exhibited an inverse relationship with the immunological score and immune checkpoint gene expression in CRC patients. The findings from the TCGA data analysis were corroborated by the PCR results obtained from CRC tissue samples. ZNF26 is markedly upregulated in colorectal cancer tissues, potentially serving as a biomarker for CRC.

Gentisic acid prevents colorectal cancer metastasis via blocking GPR81-mediated DEPDC5 degradation

BackgroundMetastasis driven by epithelial-mesenchymal transition (EMT) remains a significant contributor to the poor prognosis of colorectal cancer (CRC), and requires more effective interventions. GPR81 signaling has been linked to tumor metastasis, while lacks an efficient specific inhibitor. PurposeOur study aimed to investigate the effect and mechanism of Gentisic acid on colorectal cancer (CRC) metastasis. Study designA lung metastasis mouse model induced by tail vein injection and a subcutaneous graft tumor model were used. Gentisic acid (GA) was administered by an intraperitoneal injection. HCT116 was treated with lactate to establish an in vitro model. MethodsMC38 cells with mCherry fluorescent protein were injected into tail vein to investigate lung metastasis ability in vivo. GA was administered by intraperitoneal injection for 3 weeks. The therapeutic effect was evaluated by survival rates, histochemical analysis, RT-qPCR and live imaging. The mechanism was explored using small interfering RNA (siRNA), Western blotting, RT-qPCR and immunofluorescence. ResultsGA had a therapeutic effect on CRC metastasis and improved survival rates and pathological changes in dose-dependent manner. GA emerged as an GPR81 inhibitor, effectively suppressed EMT and mTOR signaling in CRC induced by lactate both in vivo and in vitro. Mechanistically, GA halted lactate-induce degradation of DEPDC5 through impeding the activation of Chaperone-mediated autophagy (CMA). ConclusionCMA-mediated DEPDC5 degradation is crucial for lactate/GPR81-induced CRC metastasis, and GA may be a promising candidate for metastasis by inhibiting GPR81 signaling.

Prognostic implications of MXRA8 expression in colorectal cancer and its role in tumor progression

Matrix Remodeling Associated 8 (MXRA8) is a type I transmembrane protein capable of modulating integrin signaling and regulating cell-cell interactions, and also functions as a receptor for multiple arthritogenic alphaviruses. Although limited numbers of studies have provided evidence indicating a potential role of MXRA8 in different types of cancer, the potential contrubition of MXRA8 in colorectal cancer (CRC) has not yet been fully elucidated. Therefore, our aim was to conduct a comprehensive analysis elucidating the prognostic value of MXRA8 in CRC. The results revealed that MXRA8 was highly expressed in CRC compared to normal tissue. Notably, there was a substantial correlation with the TNM stage, and elevated MXRA8 expression was indicative of a poorer prognosis in CRC cases. Furthermore, co-expression analysis indicated that MXRA8 is predominantly involved in hypoxia and epithelial-mesenchymal transition pathway. In conclusion, this study demonstrates the potential roles of MXRA8 in predicting CRC prognosis and contributes to the elucidation of how MXRA8 might be involved in the mechanisms underlying CRC carcinogenesis.

Heterogeneous expression of ARID1A in colorectal cancer indicates distinguish immune landscape and efficacy of immunotherapy

ObjectiveAT-rich interaction domain 1A (ARID1A) mutant tumors show active anti-tumor immune response, which is the potential indication of immunotherapy. However, the relationship between the heterogeneous ARID1A expression and the immune response and immunotherapy efficacy in colorectal cancer (CRC) is still unclear.MethodsWe collected 1113 cases of patients with stage I-IV CRC who underwent primary resection at Harbin Medical University Cancer Hospital. ARID1A expression in CRC tissues was assessed via immunohistochemistry (IHC). CD8, CD163 and FOXP3 were stained by IHC to identify the immune landscape. Clinicopathological features of patients were compared using statistical tests like the Wilcoxon-Mann–Whitney test or χ2 tests. Kaplan–Meier survival analysis with log-rank tests were employed.ResultsHeterogeneous ARID1A expression was categorized into integrity expression, complete expression deficiency (cd-ARID1A), partial expression deficiency (pd-ARID1A), and clonal expression deficiency (cld-ARID1A). ARID1A-deficient expression was significant association with dMMR (P value < 0.001). Patients with ARID1A deficiency, compared to ARID1A-proficient patients, exhibited increased infiltration levels of CD8 + P value < 0.0001), CD163 + P value < 0.001), and FOXP3 + P value < 0.001).cells within the tumor tissue. However, in different subgroups, only samples with complete or partial deficiency of ARID1A showed a higher abundance of lymphocyte infiltration. In patients with ARID1A-clonal expression deficiency tumor, the infiltration patterns of three immune cell types were comparable to those in ARID1A-proficient patients. Heterogeneous ARID1A expression is related to the different prognosis and immunotherapythe efficacy in CRC patients.ConclusionHeterogeneous ARID1A expression is accompanied by a different immune landscape. CRC patients with ARID1A-clonal expression deficiency do not benefit from the treatment of immune checkpoint inhibitors (ICIs).

GSTM1 and GSTP1 Polymorphisms Affect Outcome in Colorectal Adenocarcinoma

Background and Objectives: Despite improvements in screening programs, a large number of patients with colorectal cancer (CRC) are diagnosed in an advanced disease stage. Previous investigations imply that glutathione transferases (GSTs) might be associated with the development and progression of CRC. Moreover, the detoxification mechanism of oxaliplatin, which represents the first line of treatment for advanced CRC, is mediated via certain GSTs. The aim of this study was to evaluate the significance of certain GST genetic variants on CRC prognosis and the efficacy of oxaliplatin-based treatment. Materials and Methods: This prospective study included 523 patients diagnosed with CRC in the period between 2014 and 2016, at the Digestive Surgery Clinic, University Clinical Center of Serbia, Belgrade. Patients were followed for a median of 43.47 ± 17.01 months (minimum 1–63 months). Additionally, 109 patients with advanced disease, after surgical treatment, received FOLFOX6 treatment as a first-line therapy between 2014 and 2020. The Kaplan–Meier method was used to analyze cumulative survival, and the Cox proportional hazard regression model was used to study the effects of different GST genotypes on overall survival. Results: Individuals with the GSTM1-null genotype and the GSTP1 IleVal+ValVal (variant) genotype had significantly shorter survival when compared to referent genotypes (GSTM1-active and GSTP1 IleIle) (log-rank: p = 0.001). Moreover, individuals with the GSTM1-null genotype who received 5-FU-based treatment had statistically significantly shorter survival when compared to individuals with the GSTM1-active genotype (log-rank: p = 0.05). Conclusions: Both GSTM1-null and GSTP1 IleVal+ValVal (variant) genotypes are associated with significantly shorter survival in CRC patients. What is more, the GSTM1-null genotype is associated with shorter survival in patients receiving FOLOFOX6 treatment.

Fusobacterium nucleatum induces chemoresistance in colorectal cancer by inhibiting pyroptosis via the Hippo pathway

ABSTRACT Chemotherapy resistance is one of the main reasons for the poor prognosis of colorectal cancer (CRC). Moreover, dysbiosis of gut bacteria was found to be a specific environmental risk factor. In this study, enrichment of F. nucleatum was elucidated to be significantly associated with CRC recurrence after chemotherapy. Functional experiments showed that F. nucleatum could inhibit pyroptosis induced by chemotherapy drugs, thereby inducing chemoresistance. Furthermore, mechanistic investigation demonstrated that F. nucleatum could regulate the Hippo pathway and promote the expression of BCL2, thereby inhibiting the Caspase-3/GSDME pyroptosis-related pathway induced by chemotherapy drugs and mediating CRC cell chemoresistance. Taken together, these results validated the significant roles of F. nucleatum in CRC chemoresistance, which provided an innovative theoretical basis for the clinical diagnosis and therapy of CRC.

Image-based profiling and deep learning reveal morphological heterogeneity of colorectal cancer organoids

Patient-derived organoids have proven to be a highly relevant model for evaluating of disease mechanisms and drug efficacies, as they closely recapitulate in vivo physiology. Colorectal cancer organoids, specifically, exhibit a diverse range of morphologies, which have been analyzed with image-based profiling. However, the relationship between morphological subtypes and functional parameters of the organoids remains underexplored. Here, we identified two distinct morphological subtypes (“cystic” and “solid”) across 31360 bright field images using image-based profiling, which correlated differently with viability and apoptosis level of colorectal cancer organoids. Leveraging object detection neural networks, we were able to categorize single organoids achieving higher viability scores as “cystic” than “solid” subtype. Furthermore, a deep generative model was proposed to predict apoptosis intensity based on a apoptosis-featured dataset encompassing over 17000 bright field and matched fluorescent images. Notably, a significant correlation of 0.91 between the predicted value and ground truth was achived, underscoring the feasibility of this generative model as a potential means for assessing organoid functional parameters. The underlying cellular heterogeneity of the organoids, i.e., conserved colonic cell types and rare immune components, was also verified with scRNA sequencing, implying a compromised tumor microenvironment. Additionally, the “cystic” subtype was identified as a relapse phenotype featuring intestinal stem cell signatures, suggesting that this visually discernible relapse phenotype shows potential as a novel biomarker for colorectal cancer diagnosis and prognosis. In summary, our findings demonstrate that the morphological heterogeneity of colorectal cancer organoids explicitly recapitulate the association of phenotypic features and exogenous perturbations through the image-based profiling, providing new insights into disease mechanisms.

Abstract 2784: Fatty acid synthase enhances stem-like properties of normal intestinal and colorectal cancer cells via an increase in notum expression and secretion

Abstract Introduction: Overexpression of lipogenic enzymes has been associated with a poor clinical outcome in colorectal cancer (CRC). Fatty acid synthase (FASN) synthesizes palmitate which can be utilized for post-translational modifications of various proteins. Notum, a palmitoleoyl-protein, prevents the downstream activation of Wnt signaling by de-palmitoylating Wnt ligands. Notum is also a CRC stem cell marker, and its expression correlates with poor prognosis in CRC. We found that upregulation of FASN is associated with an increase in Notum expression in mouse adenoma tissues. Therefore, the purpose of this study is to elucidate the mechanisms and contribution of FASN/Notum axis in CRC. Methods: Adenoma and normal intestinal organoids, established from ApcMin/VillinCre-ERT2 and Apc/VillinCre-ERT2 mouse models with hetero- and homozygous deletion of FASN. 4-hydroxytamoxifen (4-OHT) and TVB-3664 (FASN inhibitor) treatments were used to assess the effect of FASN deletion/inhibition on organoid growth and viability. LIVE/DEAD™ Viability/Cytotoxicity and Cell Titer-Glo® 3D Cell Viability Assays were used for quantitative analysis of growth. Human NOTUM/Protein notum homolog ELISA Kit was used to analyze Notum secretion. CRC cells, NTC and FASN shRNA, and control and FASN overexpression, were used for Notum analysis. Results: The TCGA data analysis shows that Notum is significantly upregulated in CRC and its expression correlates with expression of FASN in tumor tissue. Utilizing qRT-PCR and Western blot analyses, we show that downregulation of FASN leads to a decrease in expressions of active β-catenin, Notum, and other stem cell markers in transgenic mouse models. Moreover, 4-OHT-mediated inhibition of FASN results in decrease viability and size in ApcMin/FASN/VillinCre-ERT2 and Apc/FASN/VillinCre-ERT2 organoids. Consistently, shRNA-mediated deletion of FASN decreases expression of Notum in CRC cells. In contrast, overexpression of FASN increases the expression levels of active and total β-catenin, Notum, and other stem cell markers in SW480 cells. We show that normal epithelial cells exposed to CRC cell medium exhibit stem-like phenotype which is reduced when cells are exposed to medium collected from Notum shRNA knockdown cells. Moreover, the addition of recombinant Notum restores this phenotype. Conclusion: In summary, downregulation of FASN leads to a decrease in expression of Notum and is associated with morphological changes and significant decrease in viability in organoid models. Conversely, FASN overexpression upregulates Notum expression suggesting a potential cross talk between de novo lipid synthesis and Notum. Delineating the role of FASN regulation of stem-like properties via upregulation of β-catenin signaling and expression of Notum and other stem cell markers will provide the rationale for targeting the FASN/Notum axis in CRC. Citation Format: Courtney Olivia Kelson, Josiane Weber Tessmann, Daheng He, Chi Wang, Yekaterina Zaytseva. Fatty acid synthase enhances stem-like properties of normal intestinal and colorectal cancer cells via an increase in notum expression and secretion [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 2784.

Abstract 4634: Inhibitory-κB kinase alpha as a biomarker and therapeutic target in colorectal cancer

Abstract Introduction/Aims: Colorectal cancer (CRC) remains a leading cause of cancer-related mortality. The canonical NF-κB pathway driven by IKKβ has been implicated in CRC development and progression, however less research has focused on non-canonical NF-κB signaling, regulated by inhibitory-κB kinase alpha (IKKα). This project aimed to assess IKKα, phospho-IKKα (pIKKαs176) and IKKβ expression in a retrospective CRC cohort to establish association with survival outcomes. Subsequently, this project aimed to determine the effect of abrogating IKKα activity without perturbing the canonical NF-κB pathway controlled by IKKβ using a first-in-class selective IKKα inhibitor in vitro/ex vivo. Methods: Immunohistochemical staining for IKKα/pIKKα s176/IKKβ was performed using tissue microarrays from a CRC patient cohort (n=787). QuPath® software was used to semi-quantitively assess expression levels and scores were analyzed for association with cancer-specific survival (CSS). CRC cell lines (n=3), patient-derived organoids (PDOs; n=5) and patient-derived explants (n=5) were treated with novel IKKα inhibitor SU1644 and assessed for cell viability and proliferation. Results: Positive staining for IKKα, pIKKαs176 and IKKβ was detected in tumor specimens. High cytoplasmic expression of IKKα within tumor cells was associated with reduced CSS in patients with right-sided colon cancer (HR=3.091, 95%CI; 1.128-9.467, log rank p=0.021). Conversely, high IKKβ expression was a marker of good prognosis (HR=0.627, 95%CI; 0.457-0.861, log rank p=0.004). A high ratio of IKKα to IKKβ was associated with reduced CSS in the full cohort (HR=1.404, 95%CI; 1.050-1.879, log rank p=0.021) and this was potentiated in right-sided colon cases (HR=1.772, 95%CI; 1.107-2.837, log rank p=0.016). Selective inhibition of IKKα using 1µM SU1644 in vitro caused a significant reduction in HT29 colony formation (p=0.012) and cell viability (p=0.039). PDOs showed altered cell morphology, reduced cell viability and proliferation when treated with SU1644. In the patient-derived explant model, Ki67 expression was reduced in tumor explants treated with SU1644. Conclusions: These data establish high cytoplasmic IKKα expression within tumor cells as a marker of poor prognosis in CRC and conversely high IKKβ expression as a marker of good prognosis. This highlights the importance of development of selective IKKα inhibitor SU1644. IKKα inhibition using SU1644 demonstrated anti-cancer activity in recapitulative CRC disease models. Citation Format: Kathryn A. Pennel, Molly McKenzie, Guang-Yu Lian, Jean A. Quinn, Sara Samir Foad Al-Badran, Campbell S. Roxburgh, Simon P. Mackay, Joanna Birch, Joanne Edwards. Inhibitory-κB kinase alpha as a biomarker and therapeutic target in 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 4634.

Abstract 276: Artificial intelligence-powered analysis of tumor-stroma ratio and fibroblast density as prognostic indicators in colorectal cancer

Abstract Introduction: The tumor microenvironment (TME) plays a critical role in cancer prognosis. In colorectal cancer (CRC), the tumor-stroma ratio (TSR) and cancer-associated fibroblast (CAF) density are emerging as prognostic markers. However, accurately quantifying them remains challenging. Recent studies have shown that artificial intelligence (AI)-powered analyzers can quantify features in the TME including these. Methods: Lunit SCOPE IO, an AI-powered H&amp;E whole-slide image analyzer that detects fibroblasts and segments cancer area and stromal area, was applied to evaluate TSR and CAF density in treatment-naive, stage II or III CRC surgical specimens (N = 207) from Severance Hospital. TSR was calculated as the ratio of the area of the cancer area (CA) to the sum of the CA and the cancer stromal area (CS) within a slide. CAF density was evaluated as the fibroblast density within the CA or CS, or the ratio between them. Cox survival analysis determined the hazard ratios (HRs) in progression-free survival (PFS) between the high/low TSR/CAF groups, defining high/low groups based on optimized hazard ratio (HR) cutoffs. Results: The study found a mean TSR of 0.481±0.126 and CAF densities of 69.96±37.53/mm² (cancer area) and 1844.29±440.31/mm² (stromal area). Higher TSR, lower CAF density in CA, and higher CAF density in CS were linked to better prognosis (Table 1). The mean CAF ratio (CAF density of CS divided by CAF density of CA) was 33.92±25.35, and a group with high values showed a favorable prognosis. Dividing patients based on TSR and CAF ratio, we found that high levels in either or both metrics predicted better outcomes compared to low levels in both. Table 1. Prognosis by tumor-stroma ratio (TSR) and cancer-associated fibroblast (CAF) density Factor Group Hazard ratio (95% confidence interval) Mean progression-free survival (months) p-value TSR (cutoff: 0.351) Low (N = 34) Reference 43.7 &amp;lt;0.001 High (N = 173) 0.32 (0.19 - 0.56) 67.2 CAF density of cancer area (CA) (cutoff: 46.8) Low (N = 62) Reference 69.3 0.056 High (N = 145) 1.86 (0.98 - 3.50) 60.7 CAF density of cancer stromal area (CS) (cutoff:1,901) Low (N = 116) Reference 58.2 0.015 High (N = 91) 0.50 (0.29 - 0.88) 69.9 The ratio of CAF density of CS to CA (CAF ratio) (cutoff: 53.1) Low (N = 187) Reference 61.5 0.043 High (N = 20) 0.13 (0.02 - 0.94) 80.9 Combination of TSR and CAF ratio Both low (N = 32) Reference 41.2 &amp;lt;0.001 TSR high, CAF ratio low (N = 155) 0.32 (0.19 - 0.56) 65.8 TSR low, CAF ratio high (N = 2) 0.00 (0.00 - ∞) 83.4 Both high (N = 18) 0.06 (0.01 - 0.45) 80.2 Conclusions: In this study, we found a favorable prognosis in the group with higher TSR or higher density of CAF in CS compared to CA. This result suggests that AI-enhanced analysis of TSR and CAF can effectively predict prognosis in CRC, highlighting the potential roles of these markers in cancer prognosis. Citation Format: Minsun Jung, Jun Yong Kim, Mingu Kang, Jinhee Lee, Sanghoon Song, Taebum Lee, Wonkyung Jung, Soo Ick Cho. Artificial intelligence-powered analysis of tumor-stroma ratio and fibroblast density as prognostic indicators in 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 276.

Pharmacological suppression of HHLA2 glycosylation restores anti-tumor immunity in colorectal cancer

Immunotherapy aimed at inhibiting the negative co-stimulatory molecule programmed cell death-ligand 1 (PD-L1) has limited effectiveness, with clinical response rates remaining below 10%–15%. Therefore, new immune checkpoints need to be explored. Our study focused on human endogenous retrovirus H long terminal repeat–associating protein 2 (HHLA2), a highly glycosylated member of the B7 family that is widely expressed in colorectal cancer. HHLA2 expression negatively correlates with the prognosis of colorectal cancer. Glycosylation of HHLA2, which is regulated by the glycosyltransferase STT3 oligosaccharyltransferase complex catalytic subunit A (STT3A), is crucial for protein stability and expression in cell membranes. Additionally, the binding of HHLA2 to the receptors killer cell immunoglobulin-like receptor, three immunoglobulin domains and long cytoplasmic tail 3 (KIR3DL3) and transmembrane and immunoglobulin (Ig) domain containing 2 (TMIGD2) is dependent on N-glycosylation. Moreover, N-glycosylation of HHLA2 promotes immune evasion in colorectal cancer by suppressing the immune response of NK cells. Notably, the STT3A inhibitor NGI-1 enhances the anti-tumor immune response of NK cells. Our findings provide new insights and a molecular basis for targeting HHLA2 in immunotherapy for colorectal cancer.

Abstract 2453: Soluble B7H3 has a potential of novel serum biomaker for colorectal cancer

Abstract B7H3 (also known as CD276, an immune checkpoint molecule) is aberrantly over expressed in many types of cancer. Recently, several reports indicate a crucial role for B7H3 in promoting carcinogenesis and metastasis. We investigated whether concentration of the soluble B7H3 could be used as a new prognostic predictor of colorectal cancer by measuring serum level of B7H3. Recently we established a new mAb to B7H3 and developed sandwich ELISA-system detecting human serum B7H3 with high sensitivity and specificity. Measuring the levels of B7H3 in the serum specimens of colorectal cancer donors, we examined the usefulness of B7H3 as a novel biomarker for colorectal cancers. We tested the blood from the 82 donors of colorectal cancers and 9 healthy donors who agreed in writing to this research, just before the operation. The mean value + 2SD in 9 healthy donors was set as the cutoff value. We classified cancer patients into 2 groups with high value of B7H3 and low value of B7H3. We also analyzed the relationships between serum B7H3 levels and disease-free survival (DFS) and overall survival (OS). Serum B7H3 levels were also compared with diagnostic biomarkers such as CEA and CA19-9. B7H3 immunostaining was also performed on tissue samples. The serum levels of B7H3 in patients with colorectal cancer were significantly higher than those of healthy donors. However, there were no correlation between B7H3 and other diagnostic markers CEA and CA19-9. Regarding DFS, the higher value group of serum B7H3 showed a tendency for DFS to decrease in Stage II and III. Regarding OS, there was no significant difference of serum levels of B7H3 in Stage I and IV cases, however, in Stage II and III, OS decreased significantly in the high B7H3 group. In B7H3 immunostaining, the tissue was not sufficiently stained. These data indicate that serum B7-H3 should be useful for novel biomarker for a rationale of disease monitoring and prognosis of colorectal cancer. Citation Format: Akihiro Koizumi, Tomoaki Ito, Kazunori Kato, Takumi Iwasawa, Tomoyuki Kushida, Koichi Sato, Chikako Okamoto. Soluble B7H3 has a potential of novel serum biomaker for 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 2453.

Abstract 3176: Otopetrin 3 promotes cell proliferation and regulates glycolysis via interaction with MYC in colorectal cancer

Abstract Otopetrin 3 (OTOP3) stands out as a pivotal regulator of intracellular pH through its control over proton transportation into cells, affecting fundamental cellular processes. Previous studies have shown that OTOP3 is associated with the prognosis of colorectal cancer (CRC) patients. However, the mechanism underlying OTOP3 regulation remains unclear in cancer. Our investigation reveals OTOP3 as a potent oncogene in CRC, with higher OTOP3 levels correlating with diminished overall survival rates in CRC patients. Comparative analysis between cancerous and normal colon cells highlights a pronounced overexpression of OTOP3 in cancer cells. Suppression of OTOP3 expression significantly curtailed CRC cell proliferation, colony formation, migration, and invasion, concurrently inducing apoptosis and cell cycle arrest, ultimately leading to cancer cell death. Moreover, through CHX, FBS inactivation, and MG132 treatment experiments, it was confirmed that OTOP3 regulates c-Myc expression and stability through ubiquitination and has a critical impact on CRC cell proliferation and growth. Additionally, OTOP3's modulation of HK2, PKM2, and LDHA, underscores its role in impacting cancer cell behavior via glycolytic pathways. In summary, the overexpression of OTOP3 in CRC cells drives cell proliferation and growth through the regulation of c-Myc, impacting crucial cellular processes. Additionally, it promotes these processes by influencing glycolysis. These findings provide valuable insights into potential therapeutic targets for CRC treatment, possibly involving OTOP3 and its associated pathways. Citation Format: Hyeung-Jin Jang, Wona Jee, So-Mi Park, Ye-rin Park, Seok Woo Kim, Ji Hoon Jung. Otopetrin 3 promotes cell proliferation and regulates glycolysis via interaction with MYC in 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 3176.