Colorectal Cancer Tumor Cells Research Articles

The up-regulation of SYNCRIP promotes the proliferation and tumorigenesis via DNMT3A/p16 in colorectal cancer

Heterogeneous nuclear ribonucleoproteins (hnRNPs), a group of proteins that control gene expression, have been implicated in many post-transcriptional processes. SYNCRIP (also known as hnRNP Q), a subtype of hnRNPs, has been reported to be involved in mRNA splicing and translation. In addition, the deregulation of SYNCRIP was found in colorectal cancer (CRC). However, the role of SYNCRIP in regulating CRC growth remains largely unknown. Here, we found that SYNCRIP was highly expressed in colorectal cancer by analyzing TCGA and GEPIA database. Furthermore, we confirmed the expression of SYNCRIP expression in CRC tumor and CRC cell lines. Functionally, SYNCRIP depletion using shRNA in CRC cell lines (SW480 and HCT 116) resulted in increased caspase3/7 activity and decreased cell proliferation, as well as migration. Meanwhile, overexpression of SYNCRIP showed opposite results. Mechanistically, SYNCRIP regulated the expression of DNA methyltransferases (DNMT) 3A, but not DNMT1 or DNMT3B, which affected the expression of tumor suppressor, p16. More importantly, our in vivo experiments showed that SYNCRIP depletion significantly inhibited colorectal tumor growth. Taken all together, our results suggest SYNCRIP as a potent therapeutic target in colorectal cancer.

Inhibiting circ_0000673 blocks the progression of colorectal cancer through downregulating CPSF6 via targeting miR-548b-3p.

Colorectal cancer (CRC) is one of the most common cancers, and its progression is regulated by several factors, including circular RNA (circRNA). The objective of this study was to determine the role, or roles, of circ_0000673 in CRC. We used quantitative real-time polymerase chain reaction (qPCR) to detect the expression of circ_0000673, miR-548b-3p and cleavage and polyadenylation specific factor 6 (CPSF6) in DLD-1 and RKO cells. Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assays were used to determine circ_0000673 roles in proliferation. Wound healing and transwell assays were used to detect cell migration and invasion abilities. Expression of CPSF6 protein and stem cell-associated proteins were examined using western blot. The putative relationship between miR-548b-3p and circ_0000673 or CPSF6 was verified with dual-luciferase reporter assay. The role of circ_0000673 in CRC was also investigated in a tumor xenograft assay in nude mice. Circ_0000673 expression was increased in CRC tissues and cancer cells. Silencing circ_0000673 reduced tumor cell proliferation, migration and invasion, while also decreasing cell stemness. MiR-548b-3p was found to be a target of circ_0000673, while CPSF6 was a downstream target of miR-548b-3p. The tumor-regulatory effects of si-circ_0000673, anti-miR-548b-3p and oe-CPSF6 were partially reversed by anti-miR-548b-3p, si-CPSF6 and si-circ_0000673, respectively, in rescue assays. Downregulation of circ_0000673 reduced solid tumor growth in vivo. Circ_0000673 inhibition reduced CPSF6 expression by targeting miR-548b-3p, thereby blocking proliferation, migration and invasion of CRC tumor cells.

Clinical significance of circulating tumor cells in colorectal cancer with peritoneal metastases: a prospective cohort study using a novel method for monitoring treatment response, and assessing minimal residual disease.

The treatment for patients with colorectal cancer with metastases to the peritoneum is complex and may involve both surgery and chemotherapy. Circulating tumor cells (CTCs) have been poorly investigated in peritoneal metastatic colorectal cancer. The aim of the study is to examine the role of circulating tumor cells (CTCs) as a biomarker for monitoring disease progression, treatment response and residual disease using CellMate® - a new promising in vitro diagnostic platform technology. We prospectively followed clinical outcomes of 46 patients treated with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for colorectal cancer with peritoneal metastases and examined whether CTCs were present the week of surgery. The CTC measurements were made with the CellMate® technology, which is a platform technology to detect CTCs based on the difference in biomechanical properties compared to blood resident cells. The study was registered online (ClinicalTrials.gov). CTCs were detected in 17 (37%) patients. The presence of CTCs was associated with shorter recurrence-free survival and overall survival after CRS and HIPEC. Both recurrence free survival (HR 4.00, 95%CI 1.15-13.9; P=0.029) and overall survival (HR 5.91; 95% CI 1.18-29.7; P=0.03) were significantly worse if CTCs were detected after neoadjuvant treatment. In the subgroup of patients with CTCs detected, adjuvant therapy tended to improve the prognosis while in CTC negative patients it did not. Pending a prospective multi-center trial to validate these findings, CTCs may in the future be used as a dynamic personalized biomarker for prognostication, predicting response to therapy, and for monitoring disease progression in colorectal cancer with metastases to the peritoneum.

Effect of blocking CD96 on CD8+ T cell–mediated elimination of tumor dormancy.

e14679 Background: Dormant tumor cells, characterized by quiescent state, exhibit superior tumorigenic capacity, chemotherapy resistance, and expression of stemness genes, along with reduced immune infiltration. Tumor recurrence frequently emerges from persistent dormant tumor cells, posing a formidable challenge for targeted intervention. Methods: In this study, we established a reporter gene system to isolate dormant tumor cells from implanted tumors and reimplanted them into C57BL/6 mice. The effectiveness of the anti-CD96 antibody against dormant tumor cells was assessed by measuring tumor volumes and survival. Subsequently, anti-EpCAM CAR-T cells with CD96 knockout were administered to NSG mice with established dormant tumor cells to evaluate their efficacy and toxicity in vivo. Results: In this study, we identify a novel therapeutic target for dormant tumor cells. Administering anti-CD96 antibodies, rather than anti-PD-1 antibodies, in a systemic treatment of mice effectively eradicates dormant tumor cell-mediated recurrence in a CD96 T cell-dependent manner. Notably, dormant tumor cells exhibit resistance to adoptive cell transfer therapy. Consequently, the blockade of CD96 in anti-EpCAM CAR-T cells, either through antibody treatment or knock-out approaches, holds promise for eliminating dormant tumor cells in colorectal cancer (CRC). Furthermore, knockout CD96 in CAR-T cells enhances CAR-T cell memory formation via regulating mitochondria function but also inhibits T cell exhaustion. Conclusions: In summary, targeting CD96 serves as a valuable checkpoint against dormant tumor cells, presenting a therapeutically actionable strategy for preventing disease relapse.

Anoikis-related gene signatures in colorectal cancer: implications for cell differentiation, immune infiltration, and prognostic prediction

Colorectal cancer (CRC) is a malignant tumor originating from epithelial cells of the colon or rectum, and its invasion and metastasis could be regulated by anoikis. However, the key genes and pathways regulating anoikis in CRC are still unclear and require further research. The single cell transcriptome dataset GSE221575 of GEO database was downloaded and applied to cell subpopulation type identification, intercellular communication, pseudo time cell trajectory analysis, and receptor ligand expression analysis of CRC. Meanwhile, the RNA transcriptome dataset of TCGA, the GSE39582, GSE17536, and GSE17537 datasets of GEO were downloaded and merged into one bulk transcriptome dataset. The differentially expressed genes (DEGs) related to anoikis were extracted from these data sets, and key marker genes were obtained after feature selection. A clinical prognosis prediction model was constructed based on the marker genes and the predictive effect was analyzed. Subsequently, gene pathway analysis, immune infiltration analysis, immunosuppressive point analysis, drug sensitivity analysis, and immunotherapy efficacy based on the key marker genes were conducted for the model. In this study, we used single cell datasets to determine the anoikis activity of cells and analyzed the DEGs of cells based on the score to identify the genes involved in anoikis and extracted DEGs related to the disease from the transcriptome dataset. After dimensionality reduction selection, 7 marker genes were obtained, including TIMP1, VEGFA, MYC, MSLN, EPHA2, ABHD2, and CD24. The prognostic risk model scoring system built by these 7 genes, along with patient clinical data (age, tumor stage, grade), were incorporated to create a nomogram, which predicted the 1-, 3-, and 5-years survival of CRC with accuracy of 0.818, 0.821, and 0.824. By using the scoring system, the CRC samples were divided into high/low anoikis-related prognosis risk groups, there are significant differences in immune infiltration, distribution of immune checkpoints, sensitivity to chemotherapy drugs, and efficacy of immunotherapy between these two risk groups. Anoikis genes participate in the differentiation of colorectal cancer tumor cells, promote tumor development, and could predict the prognosis of colorectal cancer.

Engineering of an EPHA2-Targeted Monobody for the Detection of Colorectal Cancer.

Colorectal cancer (CRC) is the third most common cancer worldwide, and is second only to lung cancer with respect to cancer-related deaths. Noninvasive molecular imaging using established markers is a new emerging method to diagnose CRC. The human ephrin receptor family type-A 2 (hEPHA2) oncoprotein is overexpressed at the early, but not late, stages of CRC. Previously, we reported development of an E1 monobody that is specific for hEPHA2-expressing cancer cells both in vitro and in vivo. Herein, we investigated the ability of the E1 monobody to detect hEPHA2 expressing colorectal tumors in a mouse model, as well as in CRC tissue. The expression of hEPHA2 on the surface of CRC cells was analyzed by western blotting and flow cytometry. The targeting efficacy of the E1 monobody for CRC cells was examined by flow cytometry, and immunofluorescence staining. E1 conjugated to the Renilla luciferase variant 8 (Rluc8) reporter protein was used for in vivo imaging in mice. Additionally, an enhanced green fluorescence protein (EGFP) conjugated E1 monobody was used to check the ability of the E1 monobody to target CRC tissue. The E1 monobody bound efficiently to hEPHA2-expressing CRC cell lines, and E1 conjugated to the Rluc8 reporter protein targeted tumor tissues in mice transplanted with HCT116 CRC tumor cells. Finally, E1-EGFP stained tumor tissues from human CRC patients, showing a pattern similar to that of an anti-hEPHA2 antibody. The E1 monobody has utility as an EPHA2 targeting agent for the detection of CRC.

Relationship Between Farnesoid X Receptor and Macrophage Polarization Status in Colorectal Cancer

Objective: Most colorectal cancer patients are insensitive to immunotherapy, which is associated with the polarization state of macrophages in the immune microenvironment. Research indicates that the farnesoid X receptor can modulate the immune microenvironment of colorectal cancer, but its relationship with the polarization status of macrophages requires further investigation. This study aims to investigate the expression of farnesoid X receptor in colorectal cancer, and analyze its correlation with the clinical pathological features of colorectal cancer and the polarization status of macrophages. Methods: Pathological specimens from 31 cases diagnosed with colorectal adenocarcinoma and undergoing surgery at Wuhan Central Hospital between January 2022 and December 2022 were collected. Immunohistochemistry was employed to assess the expression of farnesoid X receptor in tumor cells and tumor stroma. The quantity of CD86-positive and CD206-positive cells in the samples was also measured to reflect the infiltration of M1 and M2 macrophages in the tumor immune microenvironment. Describe the expression of farnesoid X receptor in colorectal cancer tumor cells and tumor stroma, and analyze the relationship between farnesoid X receptor expression and clinical pathological features and macrophage polarization status. Results: The positive rates of farnesoid X receptor expression in tumor cells and tumor stroma were 29.03% and 45.16%, respectively. The expression of farnesoid X receptor in tumor cells was associated with tumor location (P=0.015), with a higher incidence of farnesoid X receptor expression loss in left-sided colon cancer compared to right-sided colon cancer. The expression of farnesoid X receptor in tumor stroma was correlated with macrophage polarization status. The positive expression of farnesoid X receptor in stroma was associated with a higher infiltration of M1-type macrophages (P=0.008) and a higher M1/M2 ratio compared to the farnesoid X receptor expression loss group (P=0.003), suggesting a better response to immunotherapy and a favorable prognosis. Conclusion: Farnesoid X receptor is expressed in both colorectal cancer tumor cells and tumor stroma, showing a close association with the primary site of colorectal cancer and the polarization status of macrophages. The positive expression of farnesoid X receptor in tumor cells is predominantly observed in right-sided colorectal cancer, while the positive expression of farnesoid X receptor in tumor stroma is associated with macrophage polarization towards the M1 phenotype.

Abstract 1331: MiNK-215, an IL-15 armored FAP-targeting CAR iNKT cell therapy, effectively treats human organoid models of treatment-refractory MSS colorectal cancer (CRC) liver metastases

Abstract The presence of liver metastases in patients with microsatellite-stable (MSS) or mismatch repair proficient (pMMR) colorectal cancer (CRC) is associated with poor response to current pharmacological treatments, including immune checkpoint blockade (ICB). The tumor microenvironment (TME) of CRC liver metastases is characterized by a highly immunosuppressive phenotype that includes poor immunogenicity, a paucity of dendritic cells, elimination of tumor-specific effector T cells, and an abundance of immunosuppressive intrahepatic Kupffer cells and myeloid-derived suppressor cells. This underscores the urgent need for innovative therapeutic approaches targeted specifically to patients with CRC liver metastases. Here we describe MiNK-215, an IL-15 armored FAP-targeting CAR iNKT cell therapy, derived from the AgenT-797 allogeneic iNKT platform, as a potential novel therapeutic approach for patients with CRC liver metastases. To better model ICB refractory human MSS CRC liver metastases, we developed an ex vivo human organoid model that recapitulates the histological and immunological features of human disease. Organoids were comprised of MSS CRC cells engineered to express nuclear GFP and HLA-A2-NY-ESO-1, hepatocytes, Kupffer cell-enriched non-parenchymal cells, and HLA-matched peripheral blood mononuclear cells (PBMCs) supplemented with NY-ESO-1-reactive T cells. Organoid models of CRC lung metastases, which are traditionally more responsive to ICB therapy were also developed to compare the models to clinical experience and further validate their usefulness. Models were treated with Fc-enhanced anti-CTLA-4 (botensilimab) and anti-PD-1 (balstilimab) antibodies, or MiNK-215 to assess tumor killing and immune activation. Botensilimab and balstilimab enhanced T cell activation and cytotoxicity of CRC tumor cells in the absence of “normal” liver cells and in lung organoids. However, they were less effective in organoid models of CRC with liver metastases consistent with clinical observations. In contrast, MiNK-215 potently enhanced tumor killing by T cells in models of CRC with liver metastases. Tumor killing in CRC liver organoid models by MiNK-215 was associated with depletion of immune suppressive FAP-expressing stellate cells and increased CD8+ T cell infiltration. Our findings demonstrate that in treatment-refractory CRC-liver metastatic organoid models, MiNK-215 overcomes the limitations of ICB therapy to home to sites of disease, reprogram the TME, recruit tumor-reactive T cells and enhance tumor killing. Ex-vivo human CRC liver and lung metastatic organoid models are a novel platform that can be leveraged to rapidly identify new therapeutic approaches for potential clinical evaluation. Citation Format: Shanmugarajan Krishnan, Bishnu Joshi, Justin Keith, Ryan Frazier, Barbara Kalinowska, Jin San Choi, Stephanie Sanders, Shannon Boi, Olivier Le Tonqueze, Nick Kushner, Kah Teong Soh, Robert Stein, Tyler J. Curiel, Marc A. van Dijk, Enoch Kim, Eleni Chantzoura, Nils-Petter Rudqvist, Dhan Chand. MiNK-215, an IL-15 armored FAP-targeting CAR iNKT cell therapy, effectively treats human organoid models of treatment-refractory MSS colorectal cancer (CRC) liver metastases [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 1331.

EVA1A, a novel and promising prognostic biomarker in colorectal cancer.

The purpose of this study was to investigate the potential of EVA1A as a prognostic biomarker for Colorectal cancer (CRC). The study utilized public databases to analyze the difference in Evala mRNA expression between CRC tumor tissues and adjacent normal tissues. Additionallymunohistochemical staining was performed on 90 paired tissue samples to detect EVA1A expression. The relationship between EVA1A and clinicopathological features was examined, and a Kaplan-Meier survival analysis was conducted. Univariate and multivariate Cox analyses were employed to identify prognostic factors affecting the overall survival (OS) of CRC patients. The analysis revealed a significant increase in Evala mRNA expression in CRC tumor cells compared to normal controls from public databases (P< 0.05). Immunohistochemical staining further confirmed a significant upregulation of EVA1A expression in CRC tissues (P< 0.05). High EVA1A expression was associated with age, pathological M stage, total tumor stage, and Carbohydrate antigen CA19-9 (CA19-9). Kaplan-Meier analysis demonstrated a significant association between high EVA1A expression and poor OS. Univariate and multivariate analysis identified EVA1A as an independent risk factor for CRC prognosis. The study suggests that EVA1A is increased in CRC tumor tissues and may serve as a potential biomarker for poor prognosis in CRC.

SLC11A1 predicts the overall survival of patients with colorectal cancer.

Colorectal cancer (CRC) remains a significant contributor to cancer-related mortality, emphasizing the critical need for identifying biomarkers that can improve clinical management and patient outcomes. In this retrospective study, we analyzed tumor samples from 25 patients with metastatic CRC, categorized based on long-term (> 50 months) or short-term (< 10 months) survival. Employing the PanCancer Immune Profile Panel, encompassing 770 genes, in the discovery dataset, we identified 54 differentially expressed genes (DEGs) within the tumor microenvironment of metastatic CRC. Validation of potential biomarkers was performed using two publicly available RNA-based sequencing datasets (TCGA 1 (n=371) and TCGA 2 (n=566)). Univariate COX regression unveiled that three significant biomarkers were associated with overall survival in CRC within the discovery dataset, which were SLC11A1 (hazard ratio (HR): 4.09, P=0.012), TNFSF11 (HR: 3.67, P=0.02), and MEF2C (HR: 0.34, P=0.037). Kaplan-Meier survival curve analyses confirmed the correlation between SLC11A1 expression and overall survival in CRC across the discovery set (P=0.0071) and the two independent datasets (TCGA 1 (P=0.0016) and TCGA 2 (P=0.025)). Receiver operating characteristic curve analysis demonstrated an area under the curve ranging from 0.64 to 0.76, with sensitivity of 59% to 87% and specificity of 60% to 73% for predicting CRC overall survival. Immunohistochemistry staining further validated the strong expression of SLC11A1 protein in CRC tumor cells, with high expression correlating with short-term survival. These findings suggest that SLC11A1 serves as a predictive biomarker for overall survival in CRC patients.

PLGA-Astragalus Polysaccharide Nanovaccines Exert Therapeutic Effect in Colorectal Cancer.

Tumor vaccines have achieved remarkable progress in treating patients with various tumors in clinical studies. Nevertheless, extensive research has also revealed that tumor vaccines are not up to expectations for the treatment of solid tumors due to their low immunogenicity. Therefore, there is an urgent need to design a tumor vaccine that can stimulate a broad anti-tumor immune response. In this work, we developed a nanovaccine (NP-TCL@APS), which includes nanoparticles loaded with colorectal cancer tumor cell lysates (TCL) and Astragalus polysaccharides (APS) into poly (lactic-co-glycolic acid) to induce a robust innate immune response. The NP-TCL@APS was identified by transmission electron microscopy and Malvern laser particle size analyzer. The killing and immune activation effects of NP-TCL@APS were evaluated in vitro. Finally, safety and anti-tumor efficacy were evaluated in the colorectal cancer tumor-bearing mouse model. We found that NP-TCL@APS was preferentially uptaken by DC and further promoted the activation of DC in vitro. Additionally, nanoparticles codelivery of TCL and APS enhanced the antigen-specific CD8+ T cell response and suppressed the growth of tumors in mouse models with good biocompatibility. We successfully prepared a nanovaccine termed NP-TCL@APS, which can promote the maturation of DC and induce strong responses by T lymphocytes to exert anti-tumor effects. The strategy proposed here is promising for generating a tumor vaccine and can be extended to various types of cancers.

SPIDE: A single cell potency inference method based on the local cell-specific network entropy

For a given single cell RNA-seq data, it is critical to pinpoint key cellular stages and quantify cells’ differentiation potency along a differentiation pathway in a time course manner. Currently, several methods based on the entropy of gene functions or PPI network have been proposed to solve the problem. Nevertheless, these methods still suffer from the inaccurate interactions and noises originating from scRNA-seq profile. In this study, we proposed a cell potency inference method based on cell-specific network entropy, called SPIDE. SPIDE introduces the local weighted cell-specific network for each cell to maintain cell heterogeneity and calculates the entropy by incorporating gene expression with network structure. In this study, we compared three cell entropy estimation models on eight scRNA-Seq datasets. The results show that SPIDE obtains consistent conclusions with real cell differentiation potency on most datasets. Moreover, SPIDE accurately recovers the continuous changes of potency during cell differentiation and significantly correlates with the stemness of tumor cells in Colorectal cancer. To conclude, our study provides a universal and accurate framework for cell entropy estimation, which deepens our understanding of cell differentiation, the development of diseases and other related biological research.

Senescent tumor cells in colorectal cancer are characterized by elevated enzymatic activity of complexes 1 and 2 in oxidative phosphorylation.

Cellular senescence is defined as an irreversible cell cycle arrest caused by various internal and external insults. While the metabolic dysfunction of senescent cells in normal tissue is relatively well-established, there is a lack of information regarding the metabolic features of senescent tumor cells. Publicly available single-cell RNA-sequencing data from the GSE166555 and GSE178341 datasets were utilized to investigate the metabolic features of senescent tumor cells. To validate the single-cell RNA-sequencing data, we performed senescence-associated β-galactosidase (SA-β-Gal) staining to identify senescent tumor cells in fresh frozen colorectal cancer tissue. We also evaluated nicotinamide adenine dinucleotide dehydrogenase-tetrazolium reductase (NADH-TR) and succinate dehydrogenase (SDH) activity using enzyme histochemical methods and compared the staining with SA-β-Gal staining. MTT assay was performed to reveal the complex 1 activity of the respiratory chain in in-vitro senescence model. Single-cell RNA-sequencing data revealed an upregulation in the activity of complexes 1 and 2 in oxidative phosphorylation, despite overall mitochondrial dysfunction in senescent tumor cells. Both SA-β-Gal and enzyme histochemical staining using fresh frozen colorectal cancer tissues indicated a high correlation between SA-β-Gal positivity and NADH-TR/SDH staining positivity. MTT assay showed that senescent colorectal cancer cells exhibit higher absorbance in 600 nm wavelength. Senescent tumor cells exhibit distinct metabolic features, characterized by upregulation of complexes 1 and 2 in the oxidative phosphorylation pathway. NADH-TR and SDH staining represent efficient methods for detecting senescent tumor cells in colorectal cancer.

RNASEH1-AS1 induced by H3K27ac stabilizes ANXA2 mRNA to promote the progression of colorectal cancer through recruiting BUD13.

Colorectal cancer (CRC) is a malignant tumor with high morbidity and mortality. It is well-accepted that dysregulated lncRNAs are closely related to the development of CRC. In this study, the function and mechanism of RNASEH1-AS1 in CRC were investigated. RT-qPCR and western blot detected the expression of targeted genes in tissues and cells. CCK-8, clone formation, wound healing assay, and Transwell were applied to evaluate CRC cell malignant behaviors. ChIP, RIP, and RNA pull-down validated interactions among RNASEH1-AS1, H3K27ac, CBP, BUD13, and ANXA2. Nucleoplasmic separation and FISH assay determined the location of RNASEH1-AS1 in CRC cells. IHC assay was used to detect Ki-67 expression in tumor tissues from mice. RNASEH1-AS1 was highly expressed in CRC tumor tissues and cells. RNASEH1-AS1 silencing effectively suppressed the viability, proliferation, migration, and invasion of CRC cells. In addition, CBP-mediated H3K27ac increased RNASEH1-AS1 expression in CRC cells and RNASEH1-AS1 could elevate ANXA2 expression through recruiting BUD13. Furthermore, RNASEH1-AS1 silencing inhibited malignant phenotypes of CRC cells and tumor growth in mice through decreasing ANXA2 expression and inactivating the Wnt/β-catenin pathway. Our results revealed that RNASEH1-AS1 induced by CBP-mediated H3K27ac activated Wnt/β-catenin pathway to promote CRC progression through recruiting BUD13 to stabilize ANXA2 mRNA, which provides substantial evidence of RNASEH1-AS1 in CRC. Targeting RNASEH1-AS1 might alleviate CRC progression.

Epigenomic analysis reveals a unique DNA methylation program of metastasis-competent circulating tumor cells in colorectal cancer

Circulating tumor cells (CTCs) and epigenetic alterations are involved in the development of metastasis from solid tumors, such as colorectal cancer (CRC). The aim of this study was to characterize the DNA methylation profile of metastasis-competent CTCs in CRC. The DNA methylome of the human CRC-derived cell line CTC-MCC-41 was analyzed and compared with primary (HT29, Caco2, HCT116, RKO) and metastatic (SW620 and COLO205) CRC cells. The association between methylation and the transcriptional profile of CTC-MCC-41 was also evaluated. Differentially methylated CpGs were validated with pyrosequencing and qMSP. Compared to primary and metastatic CRC cells, the methylation profile of CTC-MCC-41 was globally different and characterized by a slight predominance of hypomethylated CpGs mainly distributed in CpG-poor regions. Promoter CpG islands and shore regions of CTC-MCC-41 displayed a unique methylation profile that was associated with the transcriptional program and relevant cancer pathways, mainly Wnt signaling. The epigenetic regulation of relevant genes in CTC-MCC-41 was validated. This study provides new insights into the epigenomic landscape of metastasis-competent CTCs, revealing biological information for metastasis development, as well as new potential biomarkers and therapeutic targets for CRC patients.

Tumor-associated macrophages confer colorectal cancer 5-fluorouracil resistance by promoting MRP1 membrane translocation via an intercellular CXCL17/CXCL22–CCR4–ATF6–GRP78 axis

Chemotherapy represents a major type of clinical treatment against colorectal cancer (CRC). Aberrant drug efflux mediated by transporters acts as a key approach for tumor cells to acquire chemotherapy resistance. Increasing evidence implies that tumor-associated macrophages (TAMs) play a pivotal role in both tumorigenesis and drug resistance. Nevertheless, the specific mechanism through which TAMs regulate drug efflux remains elusive. Here, we discovered that TAMs endow CRC cells with resistance to 5-fluorouracil (5-FU) treatment via a cell-cell interaction-mediated MRP1-dependent drug efflux process. Mechanistically, TAM-secreted C-C motif chemokine ligand 17 (CCL17) and CCL22, via membrane receptor CCR4, activated the PI3K/AKT pathway in CRC tumor cells. Specifically, phosphorylation of AKT inactivated IP3R and induced calcium aggregation in the ER, resulting in the activation of ATF6 and upregulation of GRP78. Accordingly, excessive GRP78 can interact with MRP1 and promote its translocation to the cell membrane, causing TAM-induced 5-FU efflux. Taken together, our results demonstrated that TAMs promote CRC chemotherapy resistance via elevating the expression of GRP78 to promote the membrane translocation of MRP1 and drug efflux, providing direct proof for TAM-induced drug resistance.

SNORD11B-mediated 2'-O-methylation of primary let-7a in colorectal carcinogenesis.

Evidence indicates that small nucleolar RNAs (snoRNAs) participate in tumorigenesis and development and could be promising biomarkers for colorectal cancer (CRC). Here, we examine the profile of snoRNAs in CRC and find that expression of SNORD11B is increased in CRC tumor tissues and cell lines, with a significant positive correlation between SNORD11B expression and that of its host gene NOP58. SNORD11B promotes CRC cell proliferation and invasion and inhibits apoptosis. Mechanistically, SNORD11B promotes the processing and maturation of 18 S ribosomal RNA (rRNA) by mediating 2'-O-methylated (Nm) modification on the G509 site of 18 S rRNA. Intriguingly, SNORD11B mediates Nm modification on the G225 site of MIRLET7A1HG (pri-let-7a) with a canonical motif, resulting in degradation of pri-let-7a, inhibition of DGCR8 binding, reduction in mature tumor suppressor gene let-7a-5p expression, and upregulation of downstream oncogene translation. SNORD11B performs comparably to CEA and CA199 in diagnosing CRC. High expression of SNORD11B is significantly correlated with a more advanced TNM stage and lymph node metastasis, which indicates poor prognosis.

Dual-targeting of artesunate and chloroquine to tumor cells and tumor-associated macrophages by a biomimetic PLGA nanoparticle for colorectal cancer treatment

The regimens on colorectal cancer (CRC) are clinically limited due to the ignorance of tumor-supportive microenvironments. To combine the therapeutic effects on both tumor cells growth and immunosuppressive tumor microenvironments (TME), we propose the artesunate (AS) and chloroquine (CQ) combination and develop a poly (d,l-lactide-co-glycolide) (PLGA)-based biomimetic nanoparticle for dual-targeting delivery of the drug combination. Hydroxymethyl phenylboronic acid conjugated PLGA (HPA) is synthesized to form a reactive oxygen species (ROS)-sensitive core of biomimetic nanoparticles. A mannose-modified erythrocyte membrane (Man-EM) obtained by a novel surface modification method is cloaked on the AS and CQ-loaded HPA core to receive a biomimetic nanoparticle-HPA/AS/CQ@Man-EM. It holds a strong promise in inhibiting the proliferation of CRC tumor cells and reversing the phenotypes of TAMs via targeting both tumor cells and M2-like tumor-associated macrophages (TAMs). Verifying in an orthotopic CRC mouse model, the biomimetic nanoparticles showed improved accumulation at tumor tissues and effectively suppressed the tumor growth via both inhibition of tumor cell growth and repolarization of TAMs. Notably, unbalanced distribution to the tumor cells and TAMs is the key to realize the remarkable anti-tumor effects. This work proposed an effective biomimetic nanocarrier for the CRC treatment.

A new strategy for searching determinants in colorectal cancer progression through whole-part relationship combined with multi-omics

Abstract: The high incidence and mortality of colorectal cancer (CRC) and the lack of adequate diagnostic molecules have led to poor treatment outcomes for colorectal cancer, making it particularly important to develop methods to obtain molecular with significant diagnostic effects. Here, we proposed a whole and part study strategy (early-stage colorectal cancer as “part” and colorectal cancer as “whole”) to identify specific and co-pathways of change in early-stage and colorectal cancers and to discover the determinants of colorectal cancer development. Metabolite biomarkers discovered in plasma may not necessarily reflect the pathological status of tumor tissue. To explore the determinant biomarkers associated with plasma and tumor tissue in the CRC progression, multi-omics were performed on three phases of biomarker discovery studies (discovery, identification and validation) including 128 plasma metabolomes and 84 tissue transcriptomes. Importantly, we observe that the metabolic levels of oleic acid and FA (18:2) in patients with colorectal cancer were much higher than in healthy people. Finally, biofunctional verification confirmed that oleic acid and FA (18:2) can promote the growth of colorectal cancer tumor cells and be used as plasma biomarkers for early-stage colorectal cancer. We propose a novel research strategy to discover co-pathways and important biomarkers that may be targeted for a potential role in early colorectal cancer, and our work provides a promising tool for the clinical diagnosis of colorectal cancer.

MicroRNA expression profile in isolated circulating tumor cells in colorectal cancer

Introduction. Colorectal cancer is a frequently diagnosed disease being in the third place among oncological diseases both in incidence and mortality. Currently, researchers focus on development of more accessible and reliable biomarkers of colorectal cancer to overcome the problems in diagnosis and progression prognosis of this pathology.Aim. To investigate characteristics of microRNA expression in circulating tumor cells (CTC) of patients with colorectal cancer. Materials and methods. The study included blood samples from 299 patients with colon cancer, stages II (T3–4N0M0), III (T1–4N1–2M0) and IV (T1–4N0–2M1). Circulating tumor cells were identified using EpCAM marker detection system. Relative expression of hsa-let-7i-5p, hsa-miR-126-5p, hsa-miR-143-3p, hsa-miR-21-5p, hsa-miR-25-3p, hsa-miR-26a-5p, hsa-miR-92a-3p micro RNA in CTC was measured using polymerase chain reaction.Results. Positive CTC status was observed in 188 (62.9 %) of 299 patients, negative in 111 (37.1 %). In the patient group with pT1–2 tumors, the majority of patients did not have CTC (53.3 %). In other patients with pT1–2 disease, the number of CTC was 1.2 and 4.4 times lower than in patients with pT3 and pT4 disease, respectively. In pT4, 1–3 CTC were found 2.7 and 1.7 times more frequently, 3 CTC 1.4 times more frequently than in pT1–2 and pT3, respectively (p ≤0.05). Presence of metastatic lesions increases the probability of CTC detection by the factor of 2.1: in metastases, &gt;3 CTC were observed 60.1 times more frequently than in M0 (p ≤0.05). Expression of hsa-miR-143-3p and hsa-miR-26a-5p microRNA in CTC of patients with stage III colorectal cancer was respectively 2.5 and 5 times lower than in patients with stage II disease (p &lt;0.05) and expression of hsa-miR-21-5p and hsa-miR-92a-3p microRNA was respectively 3.2 and 3 times higher (p &lt;0.05). In CTC of patients with stage IV colorectal cancer, the relative level of expression of hsa-miR-143-3p and hsa-miR-26a-5p was respectively 4.6 and 5.3 times lower (p &lt;0.05) compared to the level of expression in stage II disease, and hsa-miR-126-5p, hsa-miR-21-5p, hsa-miR-25-3p and hsa-miR-92a-3p expression levels were respectively 2.6, 4.6, 2.6 and 5.0 times higher (p&lt;0.05) (statistically significant results).Conclusion. The level of microRNA expression in CTC can be used for differential diagnosis of regional and distant metastases.