Colorectal Cancer Tumor Tissues Research Articles

Results of expression microarray analysis of tumor tissue from patients with colorectal cancer

The aim of the study was to evaluate the expression profile and search for markers of progression in tumor tissue in colorectal cancer. Materials and Methods - Tumor tissue samples obtained from videocolonoscopy in patients with verified colorectal cancer served as the material for the study. A total of 37 specimens were involved in the study. Of these, there were 14 samples with a “favorable” prognosis and 23 with an “unfavorable” prognosis. The quality and quantity of ribonucleic acid in the eluted solution were evaluated using an IMPLEN nanospectrophotometer (Germany). A SurePrint G3 HumanGeneExpv3 ArrayKit microarray kit (Agilent, USA) was used to assess gene expression. Microarrays were scanned on an InnoScan 1100 AL (USA) with subsequent image processing using Mapix Software (USA). For the procedure of searching for differentially expressed genes, we used the Moderated t-statistics method, which is implemented in the limma package. Results - Based on the scatter plot, the most divergent genes in samples with and without progression were selected. The following markers were selected: Marker9 (GZMB), Marker5 (CXCL11), Marker3 (SYNE4), Marker20 (MIR4432HG), Marker19 (ZDHHC11), Marker11 (COL17A1), Marker13 (ZDHHC11B), Marker17 (AGR3). Low-expressing genes mainly affected DNA replication and cell cycle pathways, whereas high-expressing genes affected metabolic pathways. Conclusions - We found an association of long-term outcomes with the expression of the gene combination ZDHHC11, MIR4432HG, and GZMB. Further study of this gene combination and increased sampling will allow the construction of a test system for predicting the course and response to treatment of patients with colorectal cancer.

DST regulates cisplatin resistance in colorectal cancer via PI3K/Akt pathway.

Dystonin (DST), a potential tumor suppressor gene, plays a crucial role in regulating cancer cell proliferation and resistance to chemotherapy. However, DST's specific role in colorectal cancer (CRC) has not been thoroughly investigated, and this study aims to elucidate its molecular role in modulating cisplatin (DDP) resistance in CRC. DST expression was analyzed in CRC tumors, DDP-resistant CRC tissues, paracancer tissues, and normal tissues. Lentiviral overexpression and shRNA knockdown were conducted in advanced CRC and DDP-resistant cell lines to assess cell viability, apoptosis, invasion, migration, proliferation, and angiogenesis. Xenograft mouse models studied DST's impact on CRC tumor growth and DDP resistance in vivo. DST expression was significantly reduced in CRC tumor and DDP-resistant CRC tissues compared to paracancer and normal tissues (P < .001). Upregulating DST inhibited CRC and DDP-resistant cell viability, proliferation, invasion, and migration while promoting apoptosis. DST overexpression also reduced angiogenesis and attenuated DDP-induced cytotoxicity in CRC cells. Mechanistically, DST upregulation suppressed DDP resistance in CRC cells via the PI3K/Akt signaling pathway. DST upregulation reduced CRC tumor growth and mitigated DDP resistance, in vivo. DST plays a crucial role in limiting CRC progression and overcoming DDP resistance, suggesting potential for targeted CRC therapies.

CLK3 promotes tumor proliferation by activating MYC signaling

Colorectal cancer (CRC) ranks among the leading causes of cancer-related mortality worldwide, posing a significant public health challenge. Despite advancements in treatment strategies, prognosis for advanced CRC remains poor. Here, we investigate the role of CLK3 and its interaction with the c-Myc signaling pathway in CRC progression. Our study reveals significant overexpression of CLK3 in CRC tumor tissues, correlating with disease advancement, and demonstrates that CLK3 promotes CRC cell proliferation, mediated by its activation of MYC signaling through upregulation of c-MYC expression. In vivo experiments confirm the oncogenic role of CLK3, with its loss resulting in decreased tumor growth and c-MYC expression. These findings highlight CLK3 as a potential therapeutic target in CRC, offering insights into novel treatment strategies.

Telomere transcripts act as tumor suppressor and are associated with favorable prognosis in colorectal cancer with low proliferating cell nuclear antigen expression.

Telomeric repeat-containing RNAs (TERRA) and telomerase RNA component (TERC) regulate telomerase activity (TA) and thereby contribute to telomere homeostasis by influencing telomere length (TL) and the cell immortality hallmark of cancer cells. Additionally, the non-canonical functions of telomerase reverse transcriptase (TERT) and TERRA appear to be involved in the epithelial-mesenchymal transition (EMT), which is important for cancer progression. However, the relationship between TERRA and patient prognosis has not been fully characterized. In this small-scale study, 68 patients with colorectal cancer (CRC) were evaluated for correlations between telomere biology, proliferation, and EMT gene transcripts and disease outcome. The proliferating cell nuclear antigen (PCNA) and the epithelial splicing regulatory proteins 1 and 2 (ESRP1 and ESRP2) showed a positive correlation with TERRA, while TA and TERRA exhibited an inverse correlation. Consistent with previous findings, the present study revealed higher expression levels of TERT and TERC, and increased TA and TL in CRC tumor tissue compared to adjacent non-tumor tissue. In contrast, lower expression levels of TERRA were observed in tumor tissue. Patients with high TERRA expression and low PCNA levels exhibited favorable overall survival rates compared to individuals with the inverse pattern. Furthermore, TERRA suppressed CRC tumor growth in severe combined immunodeficiency disease (SCID) mice. In conclusion, our study extends previously published research on TERRA suggesting its potential therapeutic role in telomerase-positive CRC.

Silencing GDI2 inhibits proliferation, migration and invasion of colorectal cancer through activation of p53 signaling pathway

ObjectiveTo investigate the effect of silencing GDP dissociation inhibitor 2 (GDI2) on colorectal cancer development and possible mechanisms based on transcriptomic analysis. MethodsThe differences in the expression levels of GDI2 in normal colorectal tissues and tumor tissues of colorectal cancer (CRC) patients were detected. The correlation of GDI2 expression levels with survival and clinical characteristics of CRC patients was analyzed. The effects of GDI2 expression levels on the biological functions of CRC cells were examined by CCK-8 assay, plate clone formation assay, wound healing assay, and Transwell assay. The effect of GDI2 on the proliferation and growth of xenograft tumors was investigated by a xenograft tumor model of CRC in nude mice. Based on transcriptomics, we explored the possible mechanisms and associated pathways of the effect of silencing GDI2 on CRC cells. Cellular experiments and Western blot assays were performed to verify the potential mechanisms and related pathway of GDI2 action on CRC. ResultsThe expression levels of GDI2 in CRC tissues and cells were higher than those in normal tissues and cells. The expression level of GDI2 correlated with clinical characteristics such as lymphatic metastasis, tumor stage, tumor volume, and lymphocyte count. Silencing of GDI2 reduced the proliferative activity and migration and invasion ability of CRC cells, as well as inhibited the proliferation of CRC xenograft tumors. The differentially expressed genes were significantly enriched in biological processes such as cell cycle arrest and the p53 signaling pathway after GDI2 silencing. The percentage of G0/G1 phase cells in CRC cells was increased after silencing GDI2 as verified by flow cytometry. RAB5A was highly associated with the p53 pathway and could interact with TP53 via the ZFYVE20 protein. The mutual binding between GDI2 protein and RAB5A protein was verified by immunoprecipitation assay. Silencing GDI2 while overexpressing RAB5A reversed the reduced proliferation, migration, and invasion ability as well as cell cycle arrest of CRC cells. Meanwhile, the addition of p53 signaling pathway inhibitor Pifithrin-α (PFT-α) also reversed the biological effects of silencing GDI2 on CRC cells. The p-p21 and p-p53 protein expression levels were significantly greater in the sh-GDI2 group than in the sh-NC group. However, the p-p21 and p-p53 protein expression levels were reduced after silencing GDI2 while overexpressing RAB5A. ConclusionSilencing GDI2 activates the p53 signaling pathway by regulating RAB5A expression levels, which in turn induces cell cycle arrest and ultimately affects the proliferative activity, migration, and invasive ability of CRC cells.

Discovery and Validation of Methylation Signatures in Circulating Cell-Free DNA for the Detection of Colorectal Cancer.

This study was conducted with the primary objective of assessing the performance of cfDNA methylation in the detection of colorectal cancer (CRC). Five tumor tissue, 20 peripheral blood leucocyte, and 169 cfDNA samples were collected for whole-genome bisulfite sequencing (WGBS) analysis. Bioinformatic analysis was conducted to identify differentially methylated regions (DMRs) and their functional characteristics. Quantitative methylation-specific PCR (qMSP) was used to validate the methylation levels of DMRs in the tissues and leucocytes. cfDNA samples from CRC patients and healthy controls were used to evaluate the performance of the DMR analysis. WGBS analysis revealed a decrease in DNA methylation levels in the CpG context in CRC tumor tissues compared with adjacent normal tissues. A total of 132 DMRs in cfDNA were identified as potential markers for diagnosing CRC. In a cohort of 95 CRC patients and 74 healthy controls, a combination of the three DMRs (DAB1, PPP2R5C, and FAM19A5) yielded an AUC of 0.763, achieving 64.21% sensitivity and 78.38% specificity in discriminating CRC patients from healthy controls. This study provides insights into DNA methylation patterns in CRC and identifies a set of DMRs in cfDNA with potential diagnostic value for CRC. These DMRs hold promise as biomarkers for CRC detection, offering promise for non-invasive CRC diagnosis. Further research is warranted to validate these findings in larger cohorts.

Prognostic significance of hepatocyte growth factor in non-metastatic colorectal cancer

Hepatocyte growth factor (HGF), produced by mesenchymal cells, stimulates mitogenesis and angiogenesis in tumor cells. Tumor cells of some solid tumors do not secrete HGF. The aim of the study was to evaluate the prognostic significance of HGF expression in tumor tissue in colorectal cancer (CRC). The study included 50 patients with stage II-III colorectal cancer; they underwent radical surgical treatment, followed by adjuvant chemotherapy according to the FOLFOX/XELOX regimen. In primary tumor samples, quantitative PCR was used to assess the level of HGF expression. Statistical processing of the obtained data was carried out using STATISTICA 13.0, BioStat v.7.1., and Jamovi 1.6.8 software. The study aims to study a new marker. Comparison of characteristics in the case of non-normal distribution was carried out using the nonparametric Mann–Whitney U test. Cox and Kaplan–Meier linear regression tests were used to analyze progression-free survival. When discussing the results, we used our previously obtained data on the level of expression of TGF-β and CXCL8 in the tumor tissue. As a result of the studies, it was found that in 60% of tumor samples HGF was not expressed, but it was significantly higher than in the resection line samples. Analysis of relapse-free survival in patients with CRC according to the level of HGF expression (predicted level by proportional hazards assessment – 0.7) showed that the median survival in groups 1 (HGF expression more than 0.7) and 2 (HGF expression less than 0.7) was 23.3 and 62.9 months, respectively (long rank test p = 0.215). It was shown that the level of HGF mRNA in CRC tumors does not depend on age, stage of the disease, and sensitivity to FOLFOX/XELOX chemotherapy. The expression level is significantly reduced in tumors with a KRAS mutation and increased in those with a BRAF mutation, in poorly differentiated tumors. Using the level of HGF expression in the tumor tissue of patients with non-metastatic CRC before the start of chemotherapy to assess the prognosis of the relapse-free period is only possible in conjunction with the expression of TGF-β, CXCL8 in the tissue and the level of CEA in the blood of these patients.

Cytochrome P450 F3 promotes colorectal cancer via inhibiting NRF2-mediated ferroptosis

Cytochrome P450 F3 (CYP4F3) is recognized as a disease-associated immune response initiator that is involved in the synthesis of cholesterol, steroids, and lipids. This study identified the upregulation of CYP4F3 expression in colorectal cancer (CRC) and its association with poor patient prognosis through a comparative analysis between CRC tumor tissues with normal tissues from public databases. The overexpression of CYP4F3 in CT26.wt and SW620, promoted cell proliferation and migration, a reduction of cellular oxidative stress, an up-regulation of the oxidative stress-related pathway NRF2, and an inhibition of cellular ferroptosis. Additionally, inhibition of NRF2 activity stimulated cellular ferroptosis when CYP4F3 was overexpressed. Ferroptosis, characterized by iron-dependent lipid peroxidation, is a non-apoptotic way of cell death with a critical role in cancer development. When given a ferroptosis agonist to CYP4F3-overexpression CRC cells, NRF2 was activated, and cell proliferation and migration were reduced. Furthermore, the mice subcutaneously injected with CYP4F3-overexpression CT26.wt cells formed significantly larger tumors compared to the CYP4F3-vector CT26.wt cell group. This study systematically identified an important role of CYP4F3 in CRC development as a regulator of CRC cells to escape ferroptosis via NRF2, highlighting the significance of CYP4F3 as a potential therapeutic target for CRC.

Iron Overloading Potentiates the Antitumor Activity of 5-Fluorouracil by Promoting Apoptosis and Ferroptosis in Colorectal Cancer Cells.

Resistance to 5-fluorouracil (5-FU) remains a significant challenge in colorectal cancer (CRC) treatment. Ferric ammonium citrate (FAC) is commonly used as an iron supplement due to its food-fortification properties; however, its potential role as a chemosensitizer in cancer therapy has not been studied. In this study, we explored the ability of FAC to sensitize CRC cells and increase their susceptibility to 5-FU-mediated anticancer effects. We assessed cell viability, cell cycle progression, apoptosis, mitochondrial membrane potential (MMP), reactive oxygen species (ROS) levels, ferroptosis, and iron metabolism-related protein expression using two CRC cell lines. Additionally, we conducted in silico analyses to compare iron markers in normal colon and CRC tumor tissues. Compared to controls, CRC cells pretreated with FAC and then treated with 5-FU exhibited significantly reduced growth and viability, along with increased ROS-mediated ferroptosis. Mechanistically, FAC-pretreated then 5-FU-treated CRC cells showed enhanced apoptosis, increased Bak/Bax expression, MMP depolarization, and decreased antiapoptotic protein levels (Bcl-2 and Bcl-xL). This combined treatment also led to G2/M cell cycle arrest, upregulation of p21 and p27, and downregulation of cyclin D1, c-Myc, survivin, and GPX4. Analysis of human colon tumor tissue revealed decreased expression of IRP-1, HMOX-1, and FTH1 but increased HAMP expression. In contrast, FAC-pretreated/5-FU-treated CRC cells exhibited a reverse pattern, suggesting that FAC-induced chemosensitization enhances 5-FU-mediated anticancer activity in CRC by disrupting iron homeostasis. These findings highlight the potential of iron overload as a chemosensitization strategy for improving CRC chemotherapy.

Expression Pattern of PDE4B, PDE4D, and SFRP5 Markers in Colorectal Cancer.

Background and Objectives: Colorectal cancer (CRC) is the most frequently diagnosed malignant disease of the gastrointestinal system, and new diagnostic and prognostic markers are needed to elucidate the complete tumor profile. Materials and Methods: We used CRC tumor tissues (Dukes' A-D) and adjacent noncancerous tissues of 43 patients. Immunohistochemistry was used to examine the expression of phosphodiesterase 4B (PDE4B), phosphodiesterase 4D (PDE4D), and secreted frizzled related protein 5 (SFRP5) markers. We also analyzed the expression levels of PDE4B, PDE4D, and SFRP5 in CRC tissues compared to control tissues using RNA-sequencing data from the UCSC Xena browser. Results: In CRC stages, the distribution of PDE4B-positive cells varied, with differing percentages between epithelium and lamina propria. Statistically significant differences were found in the number of PDE4B-positive epithelial cells between healthy controls and all CRC stages, as well as between different CRC stages. Similarly, significant differences were observed in the number of PDE4B-positive cells in the lamina propria between healthy controls and all CRC stages, as well as between different CRC stages. CRC stage Dukes' C exhibited a significantly higher number of PDE4B-positive cells in the lamina propria compared to CRC stage Dukes' B. Significant differences were noted in the number of PDE4D-positive epithelial cells between healthy controls and CRC stages Dukes' A, B, and D, as well as between CRC stage Dukes' C and stages A, B, and D. CRC stage Dukes' A had significantly more PDE4D-positive cells in the lamina propria compared to stage D. Significant differences were also observed in the number of SFRP5-positive cells in the lamina propria between healthy controls and all CRC stages, as well as between CRC stages Dukes' A and D. While the expression of PDE4D varied across CRC stages, the expression of SFRP5 remained consistently strong in both epithelium and lamina propria, with significant differences noted mainly in the lamina propria. The expression levels of PDE4B, PDE4D, and SFRP5 reveal significant differences in the expression of these genes between CRC patients and healthy controls, with notable implications for patient prognosis. Namely, our results demonstrate that PDE4B, PDE4D, and SFRP5 are significantly under-expressed in CRC tissues compared to control tissues. The Kaplan-Meier survival analysis and the log-rank (Mantel-Cox) test revealed distinct prognostic implications where patients with lower expression levels of SFRP5 exhibited significantly longer overall survival. The data align with our immunohistochemical results and might suggest a potential tumor-suppressive role for these genes in CRC. Conclusions: Considering significantly lower gene expression, aligned with our immunohistochemical data in tumor tissue in comparison to the control tissue, as well as the significantly poorer survival rate in the case of its higher expression, we can hypothesize that SFRP5 is the most promising biomarker for CRC out of the observed proteins. These findings suggest alterations in PDE4B, PDE4D, and SFRP5 expression during CRC progression, as well as between different stages of CRC, with potential implications for understanding the molecular mechanisms involved in CRC development and progression.

Gut microbiota affects the activation of STING pathway and thus participates in the progression of colorectal cancer

BackgroundMore and more studies showed that gut microbiota was closely related to the development of colorectal cancer (CRC). However, the specific pathway of gut microbiota regulating CRC development is still unknown.MethodsWe collected fecal samples from 14 CRC patients and 20 normal volunteers for 16 S sequencing analysis. At the same time, 14 CRC patients’ tumors and their adjacent tissues were collected for the detection of STING pathway related protein level. Mice were injected with azoxymethane (AOM) to establish an animal model of CRC, and antibiotics were given at the same time to evaluate the influence of gut microbiota on STING pathway and whether it was involved in regulating the tumor development of CRC mice.ResultsThe sequencing results showed that compared with the normal group, the gut microbiota gut microbiota of CRC patients changed significantly at different species classification levels. At the level of genus, Akkermansia, Ligilactobacillus and Subdoligranulum increased the most in CRC patients, while Bacteroides and Dialister decreased sharply. The expression of STING-related protein was significantly down-regulated in CRC tumor tissues. Antibiotic treatment of CRC mice can promote the development of tumor and inhibit the activation of STING pathway.ConclusionGut microbiota participates in CRC progress by mediating STING pathway activation.

Exploring the role of tRNA-derived small RNAs (tsRNAs) in disease: implications for HIF-1 pathway modulation.

The tRNA-derived small RNAs (tsRNAs) can be categorized into two main groups: tRNA-derived fragments (tRFs) and tRNA-derived stress-induced RNAs (tiRNAs). Each group possesses specific molecular sizes, nucleotide compositions, and distinct physiological functions. Notably, hypoxia-inducible factor-1 (HIF-1), a transcriptional activator dependent on oxygen, comprises one HIF-1β subunit and one HIF-α subunit (HIF-1α/HIF-2α/HIF-3α). The activation of HIF-1 plays a crucial role in gene transcription, influencing key aspects of cancer biology such as angiogenesis, cell survival, glucose metabolism, and invasion. The involvement of HIF-1α activation has been demonstrated in numerous human diseases, particularly cancer, making HIF-1 an attractive target for potential disease treatments. Through a series of experiments, researchers have identified two tiRNAs that interact with the HIF-1 pathway, impacting disease development: 5'tiRNA-His-GTG in colorectal cancer (CRC) and tiRNA-Val in diabetic retinopathy (DR). Specifically, 5'tiRNA-His-GTG promotes CRC development by targeting LATS2, while tiRNA-Val inhibits Sirt1, leading to HIF-1α accumulation and promoting DR development. Clinical data have further indicated that certain tsRNAs' expression levels are associated with the prognosis and pathological features of CRC patients. In CRC tumor tissues, the expression level of 5'tiRNA-His-GTG is significantly higher compared to normal tissues, and it shows a positive correlation with tumor size. Additionally, KEGG analysis has revealed multiple tRFs involved in regulating the HIF-1 pathway, including tRF-Val-AAC-016 in diabetic foot ulcers (DFU) and tRF-1001 in pathological ocular angiogenesis. This comprehensive article reviews the biological functions and mechanisms of tsRNAs related to the HIF-1 pathway in diseases, providing a promising direction for subsequent translational medicine research.

Urinary dipeptidase 1 and trefoil factor 1 are promising biomarkers for early diagnosis of colorectal cancer.

Currently utilized serum tumor markers and fecal immunochemical tests do not have sufficient diagnostic power for colorectal cancer (CRC) due to their low sensitivities. To establish non-invasive urinary protein biomarkers for early CRC diagnosis, we performed stepwise analyses employing urine samples from CRCs and healthy controls (HCs). Among 474 urine samples, 363 age- and sex-matched participants (188 HCs, 175 stage 0-III CRCs) were randomly divided into discovery (16 HCs, 16 CRCs), training (110 HCs, 110 CRCs), and validation (62 HCs, 49 CRCs) cohorts. Of the 23 urinary protein candidates comprehensively identified from mass spectrometry in the discovery cohort, urinary levels of dipeptidase 1 (uDPEP1) and Trefoil factor1 (uTFF1) were the two most significant diagnostic biomarkers for CRC in both training and validation cohorts using enzyme-linked immunosorbent assays. A urinary biomarker panel comprising uDPEP1 and uTFF1 significantly distinguished CRCs from HCs, showing area under the curves of 0.825-0.956 for stage 0-III CRC and 0.792-0.852 for stage 0/I CRC. uDPEP1 and uTFF1 also significantly distinguished colorectal adenoma (CRA) patients from HCs, with uDPEP1 and uTFF1 increasing significantly in the order of HCs, CRA patients, and CRC patients. Moreover, expression levels of DPEP1 and TFF1 were also significantly higher in the serum and tumor tissues of CRC, compared to HCs and normal tissues, respectively. This study established a promising and non-invasive urinary protein biomarker panel, which enables the early detection of CRC with high sensitivity.

Region-Specific CD16+ Neutrophils Promote Colorectal Cancer Progression by Inhibiting Natural Killer Cells.

The colon is the largest compartment of the immune system, with innate immune cells exposed to antigens in the environment. However, the mechanisms by which the innate immune system is instigated are poorly defined in colorectal cancer (CRC). Here, a population of CD16+ neutrophils that specifically accumulate in CRC tumor tissues by imaging mass cytometry (IMC), immune fluorescence, and flow cytometry, which demonstrated pro-tumor activity by disturbing natural killer (NK) cells are identified. It is found that these CD16+ neutrophils possess abnormal cholesterol accumulation due to activation of the CD16/TAK1/NF-κB axis, which upregulates scavenger receptors for cholesterol intake including CD36 and LRP1. Consequently, these region-specific CD16+ neutrophils not only competitively inhibit cholesterol intake of NK cells, which interrupts NK lipid raft formation and blocks their antitumor signaling but also release neutrophil extracellular traps (NETs) to induce the death of NK cells. Furthermore, CD16-knockout reverses the pro-tumor activity of neutrophils and restored NK cell cytotoxicity. Collectively, the findings suggest that CRC region-specific CD16+ neutrophils can be a diagnostic marker and potential therapeutic target for CRC.

Detection and comparison of tumor cell-associated microbiota from different compartments of colorectal cancer.

Intratumoral microbes play an important role in the development of colorectal cancer (CRC). However, studying intratumoral microbes in CRC faces technical challenges, as tumor microbe communities are often contaminated by fecal microbes due to the structure of the gut folds and villi. The present study aimed to develop a new method for isolating tumor cell-associated microbiota and comparing microbial populations from different compartments. The distribution of intestinal bacteria was detected using immunohistochemistry combined with 5R-16s rRNA gene sequencing to explore the effects of the sampling site and number of washes on the detection of microbiota. The 5R-16s rRNA gene sequencing was performed using 44 samples from 11 patients with CRC, including CRC tumor tissues (TT), normal tissues adjacent to CRC (NT), tumor cells (TC), and normal cells (NC). TC and NC were obtained from the TT and NT using an enzymatic digestion method. The microbiota and their potential functions in the four groups were analyzed and compared to determine the differential microbiota related to CRC. Bacteria were mainly distributed in the feces covering intestinal tissues and in the epithelial cells and macrophages within the tissues. Different sampling sites and number of washes led to detection of different microbiota distributions. Although the cleaning method could be controlled, sampling sites varied and led to different microbiota distributions. The phyla of Firmicutes and Bacteroidetes were highly abundant in the conventionally used tissue samples, whereas Proteobacteria was the most abundant phyla in the cell samples isolated with the new method (i.e., after cell enzymatic hydrolysis). Detection of CRC cell-associated microbiota using a cell enzymatic digestion method showed that some bacteria, such as Fusobacterium, Eikenella, Shewanella, and Listeria, were more abundant in TT than NT, whereas the abundance of Akkermansia was lower in TT than NT. The tumor/normal ratios of some bacteria, such as Gemella, Escherichia, Shigella, and Blautia, were different between the cell and tissue samples. The cell enzymatic digestion method reduced fecal bacterial contamination, enabling low biomass intratumoral microbiota to be detected and allowing prediction of bacterial distributions.

Cadherin 17 Nanobody-Mediated Near-Infrared-II Fluorescence Imaging-Guided Surgery and Immunotoxin Delivery for Colorectal Cancer.

Surgery and targeted therapy are of equal importance for colorectal cancer (CRC) treatment. However, complete CRC tumor resection remains challenging, and new targeted agents are also needed for efficient CRC treatment. Cadherin 17 (CDH17) is a membrane protein that is highly expressed in CRC and, therefore, is an ideal target for imaging-guided surgery and therapeutics. This study utilizes CDH17 nanobody (E8-Nb) with the near-infrared (NIR) fluorescent dye IRDye800CW to construct a NIR-II fluorescent probe, E8-Nb-IR800CW, and a Pseudomonas exotoxin (PE)-based immunotoxin, E8-Nb-PE38, to evaluate their performance for CRC imaging, imaging-guided precise tumor excision, and antitumor effects. Our results show that E8-Nb-IR800CW efficiently recognizes CDH17 in CRC cells and tumor tissues, produces high-quality NIR-II images for CRC tumors, and enables precise tumor removal guided by NIR-II imaging. Additionally, fluorescent imaging confirms the targeting ability and specificity of the immunotoxin toward CDH17-positive tumors, providing the direct visible evidence for immunotoxin therapy. E8-Nb-PE38 immunotoxin markedly delays the growth of CRC through the induction of apoptosis and immunogenic cell death (ICD) in multiple CRC tumor models. Furthermore, E8-Nb-PE38 combined with 5-FU exerts synergistically antitumor effects and extends survival. This study highlights CDH17 as a promising target for CRC imaging, imaging-guided surgery, and drug delivery. Nanobodies targeting CDH17 hold great potential to construct NIR-II fluorescent probes for surgery navigation, and PE-based toxins fused with CDH17 nanobodies represent a novel therapeutic strategy for CRC treatment. Further investigation is warranted to validate these findings for potential clinical translation.

Chondroitin polymerizing factor promotes development and progression of colorectal cancer via facilitating transcription of VEGFB.

Colorectal cancer (CRC) is a highly prevalent malignancy affecting the digestive system on a global scale. This study aimed to explore the previously unexplored role of CHPF in the progression of CRC. Our results revealed a significant upregulation of CHPF expression in CRC tumour tissues compared to normal tissues, with its levels correlating with tumour malignancy. Invitro experiments using CRC cell lines demonstrated that inhibiting CHPF expression suppressed cell proliferation, colony formation and cell migration, while promoting apoptosis. Conversely, overexpressing CHPF had the opposite effect. Additionally, our xenograft models in mice confirmed the inhibitory impact of CHPF knockdown on CRC progression using various cell models. Mechanistic investigations unveiled that CHPF may enhance VEGFB expression through E2F1-mediated transcription. Functionally, suppressing VEGFB expression successfully mitigated the oncogenic effects induced by CHPF overexpression. Collectively, these findings suggest that CHPF may act as a tumour promoter in CRC, operating in a VEGFB-dependent manner and could be a potential target for therapeutic interventions in CRC treatment.

Abstract 4683: Suppression of ARL6ip1 inhibits malignant phenotypes of human colorectal cancer cells in vivo and &amp;gt; in situ

Abstract Introduction: Conophylline is an alkaloid isolated from the leaves of the Thai plant, Ervatamia microphylla. We isolated conophylline as an inhibitor of K-Ras functions and an activator of pancreatic β-cell differentiation. It ameliorates various disease models in animals, including cancer, diabetes mellitus, NASH, and hepatic cirrhosis. On the other hand, its molecular target was determined to be ADP-ribosylation factor-like 6-interacting protein 1 (ARL6ip1) using a conophylline-biotin conjugate. ARL6ip1 is located in the endoplasmic reticulum (ER) membrane, and conophylline binds to the cytoplasmic portion of ARL6ip1. Known functions of ARL6ip1 include inhibition of apoptosis, inhibition of glutamate transporter, and modulation of the ER structure. Previously, we knocked out ARL6ip1 in human colon carcinoma cells by CRISPR-Cas9 and found that either deletion of ARL6ip1 or addition of conophylline inhibited migration, invasion and tumorigenicity in cultured cancer cells. In the present research we have studied the in vivo anticancer effect of conophylline and ARL6ip1 knockout, and the mechanism of anticancer activity in cultured cells. Materials and Methods: Conophylline was isolated from the leaves of Ervatamia microphylla. We employed HCT116 and DLD1 cell lines as human colorectal cancer cells. Cellular migration was measured by a wound-healing assay. The activity of Akt was measured by the phospho-Akt antibody. BALB/cSlc-nu/nu mice were used for the animal experiment. Results: Colon adenocarcinoma tissue microarray comparing tumor and adjacent normal tissues revealed that ARL6ip1 expression was significantly higher in cancer than in normal tissues. Intraperitoneal administration of conophylline and knockout of ARL6ip1 both inhibited the growth of HCT116 in mice. Neither influenced the bodyweight of animals. Conophylline and deletion of ARL6ip1 both inhibited the migration. Rescue of ARL6ip1 canceled the effect of ARL6ip1 deletion on migration in HCT116 and DLD1 cells. As the mechanism, either conophylline or ARL6ip1 knockout inhibited the Akt activity, which was canceled by the rescue of ARL6ip1 in both cell lines. Conclusion: ARL6ip1 was found to be highly expressed in the tumor tissue in colorectal cancer. CRISPR-Cas9 knockout of ARL6ip1 showed a similar anticancer activity as treatment with conophylline in the animal experiment. It is likely that the anticancer activity of conophylline would be mediated by Akt. Thus, ARL6ip1 would be a useful molecular target for the treatment of cancer. Citation Format: Yinzhi Lin, Sivasundaram Karnan, Hideaki Ito, Kazuo Umezawa. Suppression of ARL6ip1 inhibits malignant phenotypes of human colorectal cancer cells in vivo and &amp;gt; in situ [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 4683.

Abstract 3419: Demographic, health history, and lifestyle factors in association with biomarkers of colorectal cancer prognosis: A pilot study

Abstract Background/Objectives: Multiple demographic, health history, and lifestyle factors have been associated with prognosis of colorectal cancer (CRC), but the mechanisms underlying these associations remain poorly understood. Knowledge of these mechanisms could reveal new strategies to improve outcomes among CRC patients. The primary objective of this project was to explore the association of these factors, which were assessed pre-diagnostically, with expression of two biomarkers in CRC tumors, SPARC and PD-L1, for which lower and higher levels of expression, respectively, have been previously associated with poorer CRC prognosis. Methods: Participants were drawn from the British Columbia Generations Project (BCGP). At the time of recruitment, they completed a detailed questionnaire that ascertained demographic factors (e.g., biological sex and household income), health history (e.g., personal history of CRC screening), and lifestyle factors (daily fruit and vegetable consumption and alcohol consumption). Formalin-fixed paraffin-embedded blocks (FFPE) with adequate volumes of tumor were obtained for 49 incident CRC cases diagnosed within the BCGP. Cores were extracted from the blocks to create tumor tissue microarrays (TMAs). Slides created from thin sections of the TMAs were stained with SPARC and PD-L1 antibodies and then imaged and analyzed to calculate H-scores as measures of expression in both epithelial and non-epithelial tissues. Linear regression analyses were conducted to evaluate associations between the various factors and ln-transformed H-scores. Results: Compared to non-smokers, smokers, on average, had 47% lower SPARC H-scores (p=0.05) in the epithelial tissues of their CRC tumors. Individuals with incomes higher than $74,999/year had 33% higher SPARC H-scores (p=0.04) in their CRC tumor non-epithelial tissues than those who earned less than $74 999/year. Females had 2.8-fold greater PD-L1 H-scores (p=0.005) in their CRC tumor epithelial tissues than males. Compared to those without a history of CRC screening, those with a history of CRC screening had 2.2 and 2.0-fold greater PD-L1 H-scores in their epithelial and non-epithelial CRC tumor tissues, respectively. Conclusion: Larger-scale studies with prognostic data are needed to confirm our findings, but our results suggest that differences in the expression of SPARC and PDL-1 may contribute to the previously observed impacts of some demographic, healthy history, and lifestyle factors on CRC prognosis. Citation Format: Umaimah Zanif, Isabella Tai, Stephen Yip, Sindy Babinszky, Katy Milne, Peter Watson, Rachel Murphy, Parveen Bhatti. Demographic, health history, and lifestyle factors in association with biomarkers of colorectal cancer prognosis: A pilot study [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 3419.

Abnormal upregulation of NUBP2 contributes to cancer progression in colorectal cancer.

Colorectal cancer (CRC), a digestive tract malignancy with high mortality and morbidity, lacks effective biomarkers for clinical prognosis due to its complex molecular pathogenesis. Nucleotide binding protein 2 (NUBP2) plays a vital role in the assembly of cytosolic Fe/S protein and has been implicated in cancer progression. In this study, we found that NUBP2 was highly expressed in CRC by TCGA database analysis. Subsequently, we verified the expression ofNUBP2 in CRC tumor tissues and para-carcinoma tissues using IHC staining, andfurther investigated its association with clinicopathological parameters. In vitro cell experiments were conducted to assess the role of NUBP2 in CRC by evaluating cell proliferation, migration, and apoptosis upon NUBP2 dysregulation. Furthermore, we established a subcutaneous CRC model to evaluate the impact of NUBP2 on tumor growth in vivo. Additionally, we performed mechanistic exploration using a Human Phospho-Kinase Array-Membrane. Our results showed higher expression of NUBP2 in CRC tissues, which positively correlated with the pathological stage, indicating its involvement in tumor malignancy. Functional studies demonstrated that NUBP2 knockdown reduced cell proliferation, increased apoptosis, and impaired migration ability. Moreover, NUBP2 knockdown inhibited tumor growth in mice. We also observed significant changes in the phosphorylation level of GSK3β upon NUBP2 knockdown or overexpression. Additionally, treatment with CHIR-99021 HCl, an inhibitor of GSK3β, reversed the malignant phenotype induced by NUBP2 overexpression. Overall, this study elucidated the functional role of NUBP2 in CRC progression both in vitro and in vivo, providing insights into the molecular mechanisms underlying CRC and potential implications for targeted therapeutic strategies.