Potential Colorectal Cancer Research Articles

Establishment of liquid biopsy procedure for the analysis of circulating cell free DNA, exosomes, RNA and proteins in colorectal cancer and adenoma patients.

Liquid biopsy has an underexplored diagnostic potential in colorectal cancer (CRC). Sufficient quantity and quality of its elements (circulating cell-free DNA (ccfDNA), exosomes and exosomal RNA) are essential for accurate results. The present study aims to establish the optimal protocol for handling liquid biopsy samples. Samples were obtained by collecting peripheral blood from colorectal adenoma patients in CellSave tubes. Plasma was separated within six hours using differential centrifugation and aliquots stored at - 20/- 80°C until further processing. Three methods for isolation of ccfDNA, and two combinations of kits for isolation of exosomes and exosomal RNA were tested. The quality and quantity of ccfDNA isolates were evaluated. Exosomes were characterised by determining size, concentration, and total and specific protein content. Expression of chosen microRNAs, miR-19a-3p and miR-92-3p, which have been implicated in CRC progression, were determined. The vacuum-column-based kit showed the highest quantities of isolated ccfDNA (P-value < 0.001). Kits for exosome isolation significantly differed in size (P-value = 0.016), concentration (P-value = 0.016) and protein content (P-value = 0.016). There was no significant difference in expressions of miR-19a-3p (P-value = 0.219) and miR-92a-3p (P-value = 0.094) between the two isolation kits. The new, adapted protocol described, enables simultaneous analysis of multiple elements when investigating potential biomarkers of CRC.

Probing the Depths of Molecular Complexity: STAT3 as a Key Architect in Colorectal Cancer Pathogenesis.

Colorectal cancer (CRC) has become a significant threat in recent decades, and its incidence is predicted to continue rising. Despite notable advancements in therapeutic strategies, managing CRC poses complex challenges, primarily due to the lack of clinically feasible therapeutic targets. Among the myriad molecules implicated in CRC, the signal transducer and activator of transcription 3 (STAT3) stands out as a promising target tightly regulated by various genes. This intracellular transcription factor, spanning 750-795 amino acids and weighing approximately 92 kDa, is crucial in key cellular activities such as growth, migration, invasion, inflammation, and angiogenesis. Aberrant activation of STAT3 signaling has been linked to various cancers, including CRC. Therefore, targeting this signaling pathway holds significance for potential CRC treatment strategies.STAT3, as a central intracellular transcription factor, is implicated in colorectal cancer development by activating aberrant signaling pathways. Numerous studies have demonstrated that the abnormal hyperactivation of STAT3 in CRC tissues enhances cell proliferation, suppresses apoptosis, promotes angiogenesis, and facilitates tumor invasion and metastasis. As a focal point in colorectal cancer research, STAT3 emerges as a promising candidate for detecting and treating CRC. This review aims to present recent data on STAT3, emphasizing the activation and functions of STAT3 inhibitors in CRC. Indeed, STAT3 inhibitors have been identified to have therapeutic potential in CRC, especially inhibitors targeting the DNA-binding domain (DBD). Indeed, STAT3 inhibitors have been identified to have a therapeutic potential in CRC, especially the inhibitors targeting the DNA binding domain (DBD). For example, imatinib acts by targeting cell surface receptors, and these inhibitors have shown potential for the control and treatment of tumor growth, angiogenesis, and metastasis. Imatinib, for example acts by targeting cell surface receptors, and these inhibitors have shown the future direction toward the control and treatment of tumor growth, angiogenesis, and metastasis.

Potential regulation and prognostic model of colorectal cancer with extracellular matrix genes

BackgroundThe tumor microenvironment (TME) of colorectal cancer (CRC) mainly comprises immune cells, stromal cells, tumor cells, as well as the extracellular matrix (ECM), which holds a pivotal position. The ECM affects cancer progression, but its regulatory roles and predictive potential in CRC are not fully understood. MethodsWe analyzed transcriptomes from CRC tumors and paired normal tissues to study ECM features. Up-regulated ECM components were examined through functional enrichment analysis, and single-cell sequencing identified cell types producing collagen, regulators, and secreted factors. Transcription factor analysis and cell-cell interaction studies were conducted to identify potential regulators of ECM changes. Additionally, a prognostic model was developed using TCGA-CRC cohort data, focusing on up-regulated core ECM components. ResultsBulk RNA-seq analysis revealed a unique ECM pattern in tumors, with ECM abundance and composition significantly related to patient survival. Up-regulated ECM components were linked to various cancer-related pathways. Fibroblasts and non-fibroblasts interactions were crucial in forming the TME. Key potential regulators identified included ZNF469, PRRX2, TWIST1, and AEBP1. A prognostic model based on five ECM genes (THBS3, LAMB3, ESM1, SPRX, COL9A3) demonstrated strong associations with immune suppression and tumor angiogenesis. ConclusionsThe ECM components were involved in various cell-cell interactions and correlated with tumor development and poor survival outcomes. The ECM prognostic model components could be potential targets for novel therapeutic interventions in colorectal cancer.

Development and Characterization of Curcumin-Loaded TPGS/F127/P123 Polymeric Micelles as a Potential Therapy for Colorectal Cancer.

Colorectal cancer (CRC) is the third most prominent cancer worldwide, and the second leading cause of cancer death. Poor outcomes and limitations of current treatments fuel the search for new therapeutic options. Curcumin (CUR) is often presented as a safer alternative for cancer treatment with a staggering number of molecular targets involved in tumor initiation, promotion, and progression. Despite being promising, its therapeutic potential is hindered due to its hydrophobic nature. Hence, the ongoing development of optimal delivery strategies based on nanotechnology, such as polymeric micelles (PMs), to overcome issues in CUR solubilization and delivery to tumor cells. In this sense, this study aimed to optimize the development and stability of CUR-loaded P123:F127:TPGS PMs (PFT:CUR) based on the thin-film approach and evaluate their therapeutic potential in CRC. Overall, the results revealed that the solubility of CUR was improved when room temperature was used to hydrate the film. The PFT-CUR hydrated at room temperature presents an average hydrodynamic diameter of 15.9 ± 0.3 nm with a polydispersity index (PDI) of 0.251 ± 0.103 and a zeta potential of -1.5 ± 1.9 mV, and a 35.083 ± 1.144 encapsulation efficiency (EE%) and 3.217 ± 0.091 drug loading (DL%) were observed. To ensure the stability of the optimized PFT-CUR nanosystems, different lyophilization protocols were tested, the use of 1% of glycine (GLY) being the most promising protocol. Regarding the critical micellar concentration (CMC), it was shown that the cryoprotectant and the lyophilization process could impact it, with an increase from 0.064 mg/mL to 0.119 mg/mL. In vitro results showed greater cytotoxic effects when CUR was encapsulated compared to its free form, yet further analysis revealed the heightened cytotoxicity could be attributed to the system itself. Despite challenges, the developed CUR-loaded PM shows potential as an effective therapeutic agent for CRC. Nonetheless, the system must undergo refinements to enhance drug entrapment as well as improve overall stability.

The application of graphene oxide and ferroptosis in the diagnosis and treatment of colorectal cancer: a narrative review.

Colorectal cancer (CRC), a leading global malignancy, continues to challenge the medical community. Despite advancements in surgical, chemotherapeutic, radiation, targeted, and immunotherapeutic strategies, issues like resistance and side effects persist. This review illuminates the potential of ferroptosis, an emerging non-apoptotic cell death form, and graphene oxide (GO), with its distinctive physicochemical properties, in CRC therapy. The databases search included PubMed, Medline and Web of Science. Search terms focused on CRC, graphene, GO, ferroptosis, and related aspects in therapy and drug delivery. The time frame for literature retrieval was up to April 2024. Studies in languages other than English were excluded. Ferroptosis has been recognized for its role in addressing treatment resistance, a notable hurdle in effective CRC management. This form of cell death offers a promising avenue for enhancing the effectiveness of existing treatments. However, understanding its mechanisms and clinical implications in CRC remains an area of active research, with significant progress required for its practical application. Simultaneously, GO, a versatile two-dimensional material, has demonstrated substantial potential in biomedical applications, especially in cancer therapy. Its high specific surface area and unique π-electron domains facilitate the effective binding of chemotherapy drugs, target genes, and photosensitizers. This makes GO a promising candidate in cancer diagnosis and treatment, particularly through tumor photothermal and photodynamic therapy (PDT). Despite these advancements, GO's clinical application faces challenges, including in vitro cytotoxicity and decreased biodegradability, necessitating further research. This review focuses on the characteristics of GO and ferroptosis, as well as their applications in tumor diagnosis and treatment, with a particular emphasis on their potential in CRC.

Ergosterol and its metabolites as agonists of Liver X receptor and their anticancer potential in colorectal cancer

Aberrant cholesterol homeostasis is a well-recognized hallmark of cancer and is implicated in metastasis as well as chemotherapeutic resistance, the two major causes of cancer associated mortality. Liver X receptors (LXRs) are the key transcription factors that induce cholesterol efflux via enhancing the expression of ABCA1 and ABCG1. Therefore, a comprehensive analysis of several novel sterols namely ergosta-7,22,24(28)-trien-3β-ol (Erg1), ergosta-5,22,25-trien-3-ol (Erg2), ergosta-5,7,22,24(28)-tetraen-3β-ol (Erg3), and ergosta-7,22-dien-3β-ol (Erg4) as LXR agonists has been performed. Molecular docking studies have shown that these sterols possess higher binding affinities for LXRs as compared to the reference ligands (GW3965 and TO901317) and also formed critical activating interactions. Molecular dynamic (MD) simulations further confirmed that docking complexes made of these sterols possess significant stability. To assess the extent of LXR activation, ABCA1 promoter was cloned into luciferase reporter plasmid and transfected into HCT116 cells. It was observed that treatment with Erg, Erg2 and Erg4 led to a significant LXR activation with an EC50 of 5.64 µM, 4.83 and 3.03 µM respectively. Furthermore, a significant increase in mRNA expression of NR1H2 and LXR target genes i.e. ABCA1, ABCG1 and ApoE was observed upon Erg treatment. Flow cytometric analysis have revealed a significant increase in the accumulation of ABCA1 upon Erg treatment. Cytotoxicity studies conducted on colorectal cancer cell and normal epithelial cell line showed that these sterols are selectively toxic towards cancer cells. Taken together, our findings suggests that ergosterol activates LXRs, have significant anticancer activity and could be a likely candidate to manage aberrant cholesterol homeostasis.

Exploring Butein’s anticancer potential in colorectal cancer: Insights into proliferation inhibition, apoptosis induction, and metastasis suppression via p38 signaling

BackgroundButein, a natural chalcone found in plants, exhibits promising anti-tumor effects across cancers, yet its role in Colorectal cancer (CRC) remain largely unclear. MethodsWe utilized pharmacological, molecular, and in vivo models to assess its impact on CRC cell proliferation, apoptosis, migration, and invasion. Molecular docking and network pharmacology analyses predicted potential target proteins and pathways regulated by Butein. Experimental validations included western blotting, immunohistochemistry, and functional assays. ResultsButein significantly inhibited CRC cell proliferation, induced apoptosis, and disrupted the epithelial-mesenchymal transition (EMT). Its repression of cell migration and invasion capabilities, suggesting potential anti-metastatic properties. The activation of the p38 signaling pathway emerged as a key mechanism mediating Butein’s anti-tumor effects, supported by network pharmacology predictions and experimental evidence. ConclusionThis study highlights the multifaceted anti-cancer potential of Butein in CRC, emphasizing its promising application and the novel role of the p38 pathway.

Phosphorylation-dependent deubiquitinase OTUD3 regulates YY1 stability and promotes colorectal cancer progression

Yin Yang 1 (YY1) is a key transcription factor that has been implicated in the development of several malignancies. The stability of YY1 is regulated by the ubiquitin-proteasome system. The role of deubiquitinases (DUBs) and their impact on YY1 remain to be fully elucidated. In this study, we screened for ubiquitin-specific proteases that interact with YY1, and identified OTUD3 as a DUB for YY1. Over-expressed OTUD3 inhibited YY1 degradation, thereby increasing YY1 protein levels, whereas OTUD3 knockdown or knockout promoted YY1 degradation, thereby decreasing the proliferation of colorectal cancer (CRC). Furthermore, PLK1 mediates OTUD3 S326 phosphorylation, which further enhances OTUD3 binding and deubiquitination of YY1. In CRC tissues, elevated the expression level of OTUD3 and YY1 were significantly associated with poor prognostic outcomes. These findings suggest that the OTUD3-YY1 pathway has therapeutic potential in CRC, and OTUD3 plays a critical role in regulating YY1.

Differential expression of nickel nanoparticles of Lactobacillus plantarum on VDR/LncRNA EIF3J-DT in Colorectal cancer

Colorectal cancer (CRC) is the third most prevalent cancer worldwide. Vitamin D receptor (VDR) gene mutations and Vitamin D deficiency contribute to CRC development and progression. Certain long non-coding RNAs (lncRNAs) directly inhibit VDR gene transcription, leading to VDR mutation. Thus, targeting oncogenic lncRNAs and VDR expression is a promising strategy for effective cancer treatment. Here, we green-synthesized Lactobacillus plantarum loaded nickel oxide nanoparticles (LpNiONPs) to assess their anticancer potential in CRC by targeting long non-coding RNA EIF3J- divergent transcript (lncRNA EIF3J-DT) and VDR. The potent bioactive component present in L. plantarum was identified via gas chromatography-mass spectrometry (GC–MS) analysis, and its interaction with VDR, as well as the functional interaction with lncRNA EIF3J-DT, were evaluated using the PyRx program and RPISeq-software, respectively. The LpNiONPs were characterized using UV–Vis spectroscopy, Zeta Potential, dynamic light scattering (DLS), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) techniques. The anticancer potential of LpNiONPs against HT-29 cells was assessed through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, scratch assay, 4′,6-diamidino-2-phenylindole (DAPI)/ acridine orange-ethidium bromide (AO-EtBr) staining experiments, and reverse transcriptase-PCR to evaluate the expression of lncRNA EIF3J-DT/VDR and apoptotic-related genes. The potent bioactive compound Pyrrolo (1,2-a) pyrazine-1,4-dione in L. plantarum strongly interacts with VDR, highlighting its drug design potential. The formation of LpNiONPs was confirmed via UV–Vis spectroscopy with an absorption peak at 394 nm. LpNiONPs were positively charged, monodispersed, and stable square-shaped nanoparticles. LpNiONPs show dose-dependent cytotoxicity and induced apoptosis, confirmed by staining images in HT-29 cells. Moreover, LpNiONPs downregulated lncRNA EIF3J-DT, CYP24-A1 and BCL2 genes while upregulating VDR, cas-3, cas-9 and BAX in HT-29 cells. These findings suggest that LpNiONPs exhibit anticancer activity by promoting VDR-associated apoptosis by inhibiting lncRNA EIF3J-DT in CRC cells.

Characterization of Wnt signaling pathway under treatment of Lactobacillus acidophilus postbiotic in colorectal cancer using an integrated in silico and in vitro analysis

Colorectal cancer (CRC) is a prevalent and life-threatening cancer closely associated with the gut microbiota. Probiotics, as a vital microbiota group, interact with the host’s colonic epithelia and immune cells by releasing a diverse range of metabolites named postbiotics. The present study examined the effects of postbiotics on CRC’s prominent differentially expressed genes (DEGs) using in silico and in vitro analysis. Through single-cell RNA sequencing (scRNA-seq), we identified four DEGs in CRC, including secreted frizzled-related protein 1 (SFRP1), secreted frizzled-related protein 2 (SFRP2), secreted frizzled-related protein 4 (SFRP4), and matrix metallopeptidase 7 (MMP7). Enrichment analysis and ExpiMap, a novel deep learning-based method, determined that these DEGs are involved in the Wnt signaling pathway as a primary cascade in CRC. Also, spatial transcriptome analysis showed specific expression patterns of the SFRP2 gene in fibroblast cell type. The expression of selected DEGs was confirmed on CRC and normal adjacent tissues using Real-Time quantitative PCR (RT-qPCR). Moreover, we examined the effects of postbiotics extracted from Lactobacillus acidophilus (L. acidophilus) on the proliferation, migration, and cell cycle distribution of HT-29 cells using MTT, scratch, and flow cytometry assays. Our results showed that L. acidophilus postbiotics induce cell cycle arrest at G1 phase and also had anti-proliferative and anti-migration effects on HT-29 cells, while it did not exert anti-proliferative activity on control fibroblasts. Finally, we revealed that treating HT-29 cells with postbiotics can affect the expression of selected DEGs. We suggested that L. acidophilus postbiotics have therapeutic potential in CRC by modulating key genes in the Wnt pathway.

Emericellopsis maritima and Purpureocillium lilacinum Marine Fungi as a Source of Functional Fractions with Antioxidant and Antitumor Potential in Colorectal Cancer: A Preliminary Study

The marine environment is a promising source of natural products with possible pharmacological applications. In this sense, marine microorganisms, especially marine fungi, can produce bioactive compounds with various therapeutic properties. Colorectal cancer (CRC) represents a major health problem worldwide, since the treatments used to date are not capable of improving patient survival; that is why natural compounds from marine fungi offer a promising alternative. This study focused on evaluating the antitumor and antioxidant activity of fractions derived from the marine fungi E. maritima and P. lilacinum in two CRC cell lines T84 and SW480. Fractions Fr-EM6, Fr-EM7, Fr-EM8 and Fr-PLMOH-3 demonstrated potent cytotoxic activity in tested CRC cell lines with no activity in the non-tumor line. In particular, the Fr-PLMOH-3 fraction from P. lilacinum showed significant antiproliferative effects on T84 and SW480 cell lines and exhibited a greater cytotoxic effect on cancer stem cells compared to tumor cells. Furthermore, the Fr-EM8 fraction from E. maritima demonstrated a strong antioxidant capacity. These findings highlight the potential of compounds of marine origin as effective and selective antitumor agents for the treatment of CRC. Further studies are needed to explore the underlying mechanisms and potential clinical applications of these bioactive fractions and compounds.

Targeting of Notch, IL-1, and leptin has therapeutic potential in xenograft colorectal cancer.

Colorectal cancer (CRC) is a fatal malignancy type and its occurence still needs to be explored mechanistically. Notch, IL-1, and leptin crosstalk is reported to play a role in the proliferation, migration, and expression of proangiogenic molecules. In this study, we aimed to investigate the effect of inhibition of Notch, IL-1, and leptin on CRC. To generate colorectal cancer tumor xenografts, 1 × 107 cells from exponentially growing cultures of HCT-15 cells were injected subcutaneously, at the axillary region of the left and right rear flanks of forty NOD.CB17-Prkdcscid/J (NOD/SCID) female mice. The mice were then monitored for the development of tumors and were randomly divided into five groups when tumor sizes reached a volume of approximately 150 mm3. Mice were used to determine the effectiveness of the gamma-secretase inhibitor (DAPT, Notch inhibitor), the interleukin-1 receptor antagonist (Anakinra) and the leptin receptor antagonist (Allo aca) against tumor growth. The mice were euthanized by CO2 inhalation immediately after the treatments finished, and all efforts were made to minimize suffering. Tumors were excissed for RT-PCR and histological analysis. There is an intact Notch, IL-1, and leptin signaling axis, and in vivo antagonism of Notch, IL-1, and leptin affects mRNA and protein expression of inflammatory and angiogenic molecules. Present data suggest that targeting Notch, IL-1, and leptin may be possesses therapeutic potential in CRC.

High CD142 Level Marks Tumor-Promoting Fibroblasts with Targeting Potential in Colorectal Cancer.

Colorectal cancer (CRC) has a high incidence and is one of the leading causes of cancer-related death. The accumulation of cancer-associated fibroblasts (CAF) induces an aggressive, stem-like phenotype in tumor cells, and it indicates a poor prognosis. However, cellular heterogeneity among CAFs and the targeting of both stromal and CRC cells are not yet well resolved. Here, we identified CD142high fibroblasts with a higher stimulating effect on CRC cell proliferation via secreting more hepatocyte growth factor (HGF) compared to CD142low CAFs. We also found that combinations of inhibitors that had either a promising effect in other cancer types or are more active in CRC compared to normal colonic epithelium acted synergistically in CRC cells. Importantly, heat shock protein 90 (HSP90) inhibitor selected against CD142high fibroblasts, and both CRC cells and CAFs were sensitive to a BCL-xL inhibitor. However, targeting mitogen-activated protein kinase kinase (MEK) was ineffective in fibroblasts, and an epigenetic inhibitor selected for a tumor cell population with markers of aggressive behavior. Thus, we suggest BCL-xL and HSP90 inhibitors to eliminate cancer cells and decrease the tumor-promoting CD142high CAF population. This may be the basis of a strategy to target both CRC cells and stromal fibroblasts, resulting in the inhibition of tumor relapse.

Flat clathrin lattices are linked to metastatic potential in colorectal cancer

Clathrin assembles at the cells' plasma membrane in a multitude of clathrin-coated structures (CCSs). Among these are flat clathrin lattices (FCLs), alternative clathrin structures that have been found in specific cell types, including cancer cells. Here we show that these structures are also present in different colorectal cancer (CRC) cell lines, and that they are extremely stable with lifetimes longer than 8 h. By combining cell models representative of CRC metastasis with advanced fluorescence imaging and analysis, we discovered that the metastatic potential of CRC is associated with an aberrant membranous clathrin distribution, resulting in a higher prevalence of FCLs in cells with a higher metastatic potential. These findings suggest that clathrin organization might play an important yet unexplored role in cancer metastasis.

Molecular Mechanisms of the Antitumor Effects of Mesalazine and Its Preventive Potential in Colorectal Cancer

Chemoprevention is one of the ways to fight colorectal cancer, which is a huge challenge in oncology. Numerous pieces of evidence indicate that chronic inflammation in the course of Crohn’s disease or ulcerative colitis (UC) is a significant cancer risk factor. Epidemiologic studies suggest that long-term use of non-steroidal anti-inflammatory drugs (NSAIDs), including mesalazine, has beneficial effects on colitis-associated colorectal cancer. Mesalazine is a first-line therapy for UC and is also widely used for maintaining remission in UC. Data showed that mesalazine has antiproliferative properties associated with cyclooxygenase (COX) inhibition but can also act through COX-independent pathways. This review summarizes knowledge about mesalazine’s molecular mechanisms of action and chemopreventive effect by which it could interfere with colorectal cancer cell proliferation and survival.

A Fecal-Microbial-Extracellular-Vesicles-Based Metabolomics Machine Learning Framework and Biomarker Discovery for Predicting Colorectal Cancer Patients

Colorectal cancer (CRC) is one of the most common and lethal diseases among all types of cancer, and metabolites play a significant role in the development of this complex disease. This study aimed to identify potential biomarkers and targets in the diagnosis and treatment of CRC using high-throughput metabolomics. Metabolite data extracted from the feces of CRC patients and healthy volunteers were normalized with the median normalization and Pareto scale for multivariate analysis. Univariate ROC analysis, the t-test, and analysis of fold changes (FCs) were applied to identify biomarker candidate metabolites in CRC patients. Only metabolites that overlapped the two different statistical approaches (false-discovery-rate-corrected p-value &lt; 0.05 and AUC &gt; 0.70) were considered in the further analysis. Multivariate analysis was performed with biomarker candidate metabolites based on linear support vector machines (SVM), partial least squares discrimination analysis (PLS-DA), and random forests (RF). The model identified five biomarker candidate metabolites that were significantly and differently expressed (adjusted p-value &lt; 0.05) in CRC patients compared to healthy controls. The metabolites were succinic acid, aminoisobutyric acid, butyric acid, isoleucine, and leucine. Aminoisobutyric acid was the metabolite with the highest discriminatory potential in CRC, with an AUC equal to 0.806 (95% CI = 0.700–0.897), and was down-regulated in CRC patients. The SVM model showed the most substantial discrimination capacity for the five metabolites selected in the CRC screening, with an AUC of 0.985 (95% CI: 0.94–1).

The Ketogenic Diet in Colorectal Cancer: A Means to an End.

Some diets, such as high lipid and high glucose diets, are known to increase the risk of colorectal cancer. On the other hand, little is known about diets that prevent colonic carcinogenesis. The ketogenic diet, which is characterized by high fat and very low carbohydrate content, is one such diet. The ketogenic diet decreases the amount of available glucose for tumors and shifts to the production of ketone bodies as an alternative energy source for healthy cells. Cancer cells are unable to use the ketone bodies for energy thus depriving them of the energy needed for progression and survival. Many studies reported the beneficial effects of the ketogenic diet in several types of cancers. Recently, the ketone body β-hydroxybutyrate has been found to possess anti-tumor potential in colorectal cancer. Despite its beneficial effects, the ketogenic diet also has some drawbacks, some of which are related to gastrointestinal disorders and weight loss. Thus, studies are being directed at this time towards finding alternatives to following a strict ketogenic diet and supplementing patients with the ketone bodies responsible for its beneficial effects in the hope of overcoming some potential setbacks. This article discusses the mechanism by which a ketogenic diet influences growth and proliferation of tumor cells, it sheds the light on the most recent trials regarding its use as an adjunctive measure to chemotherapy in patients with metastatic colorectal cancer, and it explains the limitations of its usage in metastatic patients and the promising role of exogenous ketone supplementation in this setting.

Plasma central carbon metabolite changes associated with KRAS mutation and circulating tumor DNA (ctDNA) status in colorectal cancer (CRC).

181 Background: KRAS mutations have been widely characterized as markers of poor prognosis in CRC. In stage IV CRC, KRAS mutations are predictive of benefit to anti-EGFR therapy. ctDNA has increasingly been recognized as a prognostic biomarker in CRC as well. We evaluated the association between plasma metabolites and KRAS mutation or ctDNA status in a longitudinal, observational cohort of patients with stage I-IV CRC. Methods: This was a retrospective analysis of prospectively collected blood samples from a single-institute cohort of patients with stage I-IV CRC. All blood samples were collected at pre-chemotherapy baseline. A modified Epi proColon 2.0 CE (Epigenomics AG) assay was used for plasma ctDNA testing on the methylated SEPTIN9 gene (mSEPT9). ctDNA positivity was defined as a mSEPT9 percentage of methylation reference (PMR) value greater than zero. Up to 150 metabolites of central carbon metabolism were analyzed by mass spectrometry and high-performance liquid chromatography. Analytes were compared by relative area under the curve (AUC) and differences evaluated by ANOVA. The mean AUC was used in patients with metabolites measured from &gt; 1 timepoint of collection. Patients were stratified by ctDNA status (positive or negative) and KRAS mutant (MT) or wildtype (WT) status. Results: A total of 32 patients were included with median age 65 years (range 20-90). The majority were female (53%) and had stage IV disease (78%). Of 25 patients with stage IV CRC, 88% had pre-chemotherapy blood samples collected in the first-line setting. Most patients were KRAS MT (44%) compared to KRAS WT (37%) or unknown KRAS status (19%). The most common KRAS MT subtypes were G12D (29%), G12V (29%), G13D (21%), and G12C (14%). The mean overall survival in this cohort was 27.4 months while the mean mSEPT9 PMR value was 2553.6. When stratified by ctDNA status, ctDNA positivity was associated with decreased levels of essential amino acids (lysine, methionine, threonine) and the non-essential amino acid arginine (all p &lt; 0.05). Compared to KRAS WT tumors, KRAS MT tumors were associated with increased levels of proline, phenylalanine, and intermediates of glycolysis (lactate), MTA cycle (SAM, 5-Methioadenosine), and O-GlcNAcylation (GlcNac, all p &lt; 0.05). Conclusions: We are the first to demonstrate the feasibility of associating central carbon metabolites with ctDNA and KRAS mutation status. As ctDNA positivity and KRAS MT status have evolving prognostic potential in CRC, associated metabolic signatures may identify metabolic pathways for novel biomarker development. Our findings also show that KRAS MT CRC appears to be enriched in intermediates of glycolytic, methyl donor, and O-GlcNAcylation pathways.

Abstract 2800: Use of an optimized machine learning algorithm to develop DNA methylation markers for detecting colorectal cancer (CRC)

Abstract Introduction: Epigenetic changes including methylation occur early in tumorigenesis and are known to be highly pervasive across a tumor type. The DNA methylation pattern can vary between individuals with or without cancer and also in patients with cancer of different origins. In this study, we investigated the discovery of comprehensive markers and validation of the diagnostic and prognostic potential of colorectal cancer. Methods: Patients with various stage of colorectal cancer were eligible for the current study, mainly stage III. We generated genome-wide methylation data from 379 colorectal cancer (CRC) tissues and 330 available paired adjacent normal mucosa tissues from Korean patients by Illumina EPIC Human Methylation microarray targeting 860,000~ CpG sites. A machine learning algorithm was used to build an optimized prediction model and select the tumor specific markers based on through theses CpG sites. Then, the risk score was devised for prognosis using this marker set. Finally, in order to validate the rule of CpG sites, the genomic location and pathway enrichment analysis was performed by CHROMHMM and Metascape. Results: 379 colorectal cancer tissues and 330 paired adjacent normal mucosal tissues were included for analysis. Clinical stages of the included patients were, III in N (61.2%), II in N (19.5%), and IV in N (11.9%). A total of 305 methylation markers that showed statistically significant differences between normal and cancer tissues were selected. Our model could accurately identify CRC (areas under the curve for the training and validation cohorts: 0.968 and 0.984, respectively). Using our prediction model, the colorectal cancer patients were predicted as colorectal cancer accurately in the methylation data from TCGA (COREAD; colorectal cancer tissue DNA) and GEO dataset (plasma cfDNA from colorectal cancer patients). The risk score comprising the subset of 305 methylation markers was calculated, and poor prognosis was predicted in the high-risk score group (overall survival P &amp;lt;0.1, progression-free survival P &amp;lt; 0.01). Gene ontology (GO) enrichment analysis showed that the 305 CpG sites were enriched in transcription regulatory regions (160/305, 52.5%) and were associated with developmental process and carcinogenesis (GO: 0032502, P &amp;lt;0.001; C4721208, P &amp;lt;0.001). Conclusions: In summary, the performance of our prediction model with these 305 CpG sites was highly accurate for CRC diagnosis, and the optimized risk score could predict the prognosis of Korean CRC patients Citation Format: Jun-Kyu Kang, Su Yeon Kim, Yoojoo Lim, Hwang-Phill Kim, Tae-You Kim. Use of an optimized machine learning algorithm to develop DNA methylation markers for detecting colorectal cancer (CRC) [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 2800.

Abstract 1960: Invasive potential of colorectal cancer through tumor budding in 3D

Abstract Background and Objectives: Tumor budding (TB) is defined as isolated single cancer cells or clusters of up to four cells located at the invasive tumor front of colorectal cancer (CRC) and other solid cancers. Despite the growing body of evidence establishing TB as a strong independent prognostic marker in CRC, further investigation is needed to elucidate the biological mechanisms behind TB and its invasive potential. Pseudobudding (PsB), in contrast to TB, is defined as single cancer cells or clusters of up to four cells that occur due to gland disruption and external influences such as inflammation. We hypothesize that the invasive potential of a tumor is therefore better reflected by the active process of TB rather than through the reactive process of PsB. By improved visualization of the invasive tumor front, we can characterize TB and PsB, elucidate their underlying biological processes, and improve future TB scoring accuracy in routine diagnostic practice. Methods: Cases containing TB and PsB were selected from the pathology archives. Thick sections (80-90µm) of formalin-fixed paraffin-embedded CRC tissue were taken using a microtome and stained using a free-floating immunostaining protocol for Pan-cytokeratin (epithelium) and DAPI (nuclei). Thick sections were imaged via confocal microscopy. Three-dimensional z-stacks were processed and analyzed using FIJI software. Tissue microarrays (TMAs) of regions with TB and PsB were created and RNA spatial transcriptomics was conducted on thin TMA sections (5µm) using the Nanostring GeoMx Digital Spatial Profiling Platform. Results: For sections where the invasive margin contained TB, both single cells and cell clusters appear isolated from the core tumor in 3D. These single cells and cell clusters exhibit migratory and invasive features associated with epithelial-mesenchymal transition (EMT), as evident by complete loss of cell-to-cell adhesions and shape shifting through elongation of the entire cell. In contrast, PsB is characterized by cellular debris surrounding a discontinuous epithelial lining. Undivided cells and cell clusters within the damaged area are observed as involuntarily disassociated with lagging remnants of cell-to-cell adhesions. This may be due to inflammatory cells disrupting the extracellular matrix and pulling the cells apart from one another. The identification of differing morphologies allows for further study of the RNA spatial transcriptome (of which the data will be presented during the meeting). Conclusion: Our findings show that TB and PsB are independent features within the invasive tumor margin which represent two separate biological processes. Considering the strong predictive capacity of TB as a marker of poor prognosis in CRC, TB scoring within routine diagnostic practice benefits from avoiding areas with a strong inflammatory reaction and PsB. Citation Format: Tariq Haddad, Luuk van den Dobbelsteen, Alessandro Lugli, Shannon van Lent-van Vliet, Femke Simmer, Inti Zlobec, Iris Nagtegaal. Invasive potential of colorectal cancer through tumor budding in 3D [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 1960.