Promoted Colorectal Cancer Cell Migration Research Articles

Preliminary Study of the Role of INPP4B in Promoting Colorectal Cancer Metastasis and the Mechanisms Involved

To investigate the expression of inositol polyphosphate 4-phosphatase type Ⅱ B (INPP4B) in colorectal cancer (CRC) and the relevant clinical significance, to determine the relationship between INPP4B and matrix metallopeptidase 7 (MMP7) in CRC cells, and to make preliminary exploration of the effects of INPP4B on the proliferation and migration of CRC cells and mechanisms involved. The TIMER2.0 and GEPIA2 databases were used to analyze the differences in INPP4B expression between cancer and para-cancerous tissues and the effects of such differences on the prognosis of CRC. The expression of INPP4B in 102 surgically resected CRC tumors was determined by immunohistochemistry (IHC), and the correlation between INPP4B and clinical pathological indicators was analyzed. In CRC cells with overexpressed/knocked-down INPP4B, the expression of INPP4B and MMP7 were examined by real time fluorogenic quantitative PCR, the protein expression of INPP4B was assessed by Western blot, cell proliferation was determined using the CellTiter 96® AQueous One assay, and cell migration and invasion were assessed using wound healing assay and real-time label-free dynamic cell analysis (RTCA). The LinkedOmics database was used to analyze signaling pathways related to INPP4B function, and the role of potential key molecules was validated at the cellular level. Analysis with the TIMER2.0 database and GEPIA2 database showed elevated INPP4B expression (colon adenocarcinoma [COAD]: 2.30, rectal adenocarcinoma [READ]: 2.33) in CRC compared to normal tissue (COAD: 1.91, READ: 1.89). IHC testing confirmed that INPP4B was upregulated in clinical CRC tissues and paracancerous tissues (P<0.001). Cox regression model analysis showed that INPP4B (hazards ratio [HR]=1.457, 95% confidence interval [CI]: 1.003-2.115) affected the prognosis of CRC, and the Kaplan-Meier curve showed that patients with high INPP4B expression had shorter overall survival (P<0.05). χ 2 test was performed to analyze the relationship between INPP4B expression and clinicopathological indexes, and it was found that high expression of INPP4B was correlated with lymph node metastasis (χ 2=3.997, P=0.046) and neural invasion(χ 2=8.511, P=0.004). In in vitro experiments, CRC cells overexpressing INPP4B showed a significantly increased cell proliferation and migration compared to the cells in the control group (P<0.05). Analysis using the LinkedOmics database showed that INPP4B was correlated with extracellular matrix remodeling and cell migration. Pearson's correlation analysis showed that MMP7 was positively correlated with INPP4B (r=0.3782, P<0.001). INPP4B overexpression or knockdown in vitro also led to the upregulation or the downregulation of MMP7 expression in CRC cells. INPP4B is highly expressed in CRC tissues and significantly correlated with lymph node metastasis, neural invasion, and patient prognosis. MMP7 may mediate the role of INPP4B in promoting CRC cell migration and invasion.

Investigation of ENO2 as a promising novel marker for the progression of colorectal cancer with microsatellite instability-high

BackgroundMicrosatellite instability-high (MSI-H) has emerged as a significant biological characteristic of colorectal cancer (CRC). Studies reported that MSI-H CRC generally had a better prognosis than microsatellite stable (MSS)/microsatellite instability-low (MSI-L) CRC, but some MSI-H CRC patients exhibited distinctive molecular characteristics and experienced a less favorable prognosis. In this study, our objective was to explore the metabolic transcript-related subtypes of MSI-H CRC and identify a biomarker for predicting survival outcomes.MethodsSingle-cell RNA sequencing (scRNA-seq) data of MSI-H CRC patients were obtained from the Gene Expression Omnibus (GEO) database. By utilizing the copy number variation (CNV) score, a malignant cell subpopulation was identified at the single-cell level. The metabolic landscape of various cell types was examined using metabolic pathway gene sets. Subsequently, functional experiments were conducted to investigate the biological significance of the hub gene in MSI-H CRC. Finally, the predictive potential of the hub gene was assessed using a nomogram.ResultsThis study revealed a malignant tumor cell subpopulation from the single-cell RNA sequencing (scRNA-seq) data. MSI-H CRC was clustered into two subtypes based on the expression profiles of metabolism-related genes, and ENO2 was identified as a hub gene. Functional experiments with ENO2 knockdown and overexpression demonstrated its role in promoting CRC cell migration, invasion, glycolysis, and epithelial-mesenchymal transition (EMT) in vitro. High expression of ENO2 in MSI-H CRC patients was associated with worse clinical outcomes, including increased tumor invasion depth (p = 0.007) and greater likelihood of perineural invasion (p = 0.015). Furthermore, the nomogram and calibration curves based on ENO2 showed potential prognosis predictive performance.ConclusionOur findings suggest that ENO2 serves as a novel prognostic biomarker and is associated with the progression of MSI-H CRC.

High MEIS3 Expression Indicates a Poor Prognosis for Patients with Stage II/III Colorectal Cancer.

The Wnt/β-catenin signaling pathway plays crucial roles in tumor budding and the epithelial-mesenchymal transition (EMT). Myeloid ecotropic viral insertion site 3 (MEIS3)-a direct target of Wnt/β-catenin-promotes vagal neural crest cell migration into the gut tissue during development; however, its role in cancer progression remains unclear. In this study, the role of MEIS3 in colorectal cancer (CRC) progression was investigated. We analyzed the association between MEIS3 protein expression and the clinical stages of CRC patients, and the effect on tumor cell migration and invasion by wound healing and transwell assays. Finally, we analyzed the association between MEIS3 expression and the disease-free survival (DFS) and overall survival of CRC patients through Kaplan-Meier analysis. We found that MEIS3 expression was strongly associated with CRC progression and could be employed to assess DFS in postoperative patients. MEIS3-positive cells were mainly distributed in the growth front and tumor-stroma interface of the CRC tissues, which contain abundant EMT-active and tumor budding cells dominating cancer metastasis. Moreover, MEIS3 promoted CRC cell migration and invasion by regulating effectors including laminin subunit beta 1, matrix metalloprotein 2, and vimentin. MEIS3 protein expression increased with CRC progression according to the clinical stage, which could be used as a biomarker to stratify CRC patients. The 5-year DFS of MEIS3-high patients was poorer than that of MEIS3-low patients (40.6% vs. 61.7%; p < 0.0001). Moreover, the 5-year DFS of stage II patients with MEIS3-high expression (53.4%) was comparable to that of stage III patients with MEIS3-low expression (49.5%), while the 5-year DFS of MEIS3-high patients in stage III (30.9%) was comparable to that of stage IV patients (29.6%). This study showed that MEIS3 can promote cancer cell metastasis and thus may be a promising biomarker for higher rates of recurrence in postoperative patients with stage II/III CRC.

A positive feedback circuit driven by m6A-modified circular RNA facilitates colorectal cancer liver metastasis

BackgroundLiver metastasis is the leading cause of death in patients with colorectal cancer (CRC). Emerge evidence suggests that circular RNA (circRNA) is a pivotal player in cancer progression. However, its role in CRC liver metastasis remains largely unknown.MethodsCirc-YAP expression was detected by qRT-PCR and in situ hybridization. The function of circ-YAP was tested by wound healing, transwell and CCK-8 assays. RNA immunoprecipitation, pull-down, luciferase reporter, chromatin immunoprecipitation assays were used to investigate the mechanism underlying circ-YAP promoting CRC liver metastasis. CRC liver metastasis animal model was established to assess the effect of circ-YAP in vivo.ResultsCirc-YAP was notably upregulated in CRC with liver metastasis, which was associated with dismal prognosis. Circ-YAP promoted CRC cell migration and invasion in vitro, and facilitated liver metastasis in patient-derived xenografts (PDX) models in vivo. Mechanistically, circ-YAP encoded a novel truncated protein containing 220 amino acids, termed as YAP-220aa, which competitively bound to LATS1, resulting in YAP dephosphorylation and nuclear translocation, thereby activating a cohort of metastasis-promoting genes. Importantly, N6-methyladenosine (m6A) modification orchestrated efficient initiation of circ-YAP translation, requiring m6A reader YTHDF3 and eIF4G2 translation initiation complex. Intriguingly, circ-YAP was transcriptionally enhanced by YAP/TEAD complex, thus forming a positive regulatory feed-forward loop.ConclusionsOur findings reveal a previously uncharacterized oncoprotein encoded by circ-YAP, implying a promising biomarker and therapeutic target for CRC patients with liver metastasis.

Microcystin-LR-Induced Interaction between M2 Tumor-Associated Macrophage and Colorectal Cancer Cell Promotes Colorectal Cancer Cell Migration through Regulating the Expression of TGF-β1 and CST3

Microcystin-LR (MC-LR) is a toxic secondary metabolite produced by cyanobacteria that has been demonstrated to promote colorectal cancer (CRC). However, the mechanism by which MC-LR enhances CRC in the tumor microenvironment (TME) is poorly understood. To elucidate its role in TME, a co-culture system was established using CRC cells and M2 macrophages in a Transwell chamber. The study found that MC-LR promotes CRC cell migration by upregulating TGF-β1 expression and secretion in M2 macrophages and downregulating CST3 in CRC cells. Neutralizing TGF-β1 increased CST3 expression in CRC cells, while overexpressing CST3 in CRC cells suppressed TGF-β1 expression in M2 macrophages, both of which weakened MC-LR-induced cellular motility in the co-culture system. In vivo, the mice in the MC-LR/AOM/DSS group had more tumor nodules, deeper tumor invasion, and higher M2 macrophage infiltration compared to the AOM/DSS group, and the expression of TGF-β1 and CST3 in tumors was consistent with the cellular level. Overall, this study provides insights into the regulatory mechanism of MC-LR on TME, revealing that MC-LR upregulates the expression and secretion of TGF-β1 in M2 macrophages, which in turn inhibits the expression of CST3 in CRC cells to promote migration.

RFC5, regulated by circ_0038985/miR‐3614‐5p, functions as an oncogene in the progression of colorectal cancer

Replication factor C 5 (RFC5) is involved in a variety of biological functions of cancer. However, the expression pattern of RFC5 and the underlying mechanisms in colorectal cancer (CRC) remain elusive. Here, we show that RFC5 is significantly upregulated in CRC tissues and cells. Patients with CRC and increased RFC5 levels have an unfavorable prognosis. RFC5 can promote the proliferation, migration, and invasion of CRC cells and inhibit the apoptosis of CRC cells. Additionally, upstream of RFC5, we constructed the competing endogenous RNA network and confirmed that RFC5 in this network was inhibited by miR-3614-5p by directly targeting its 3'-untranslated regions. We verified that circ_0038985, which is positively correlated with RFC5, directly targeted miR-3614-5p. Overexpression of circ_0038985 promoted CRC cell migration and invasion, and these effects were partially reversed by the reintroduction of miR-3614-5p. Moreover, we found that RFC5 may promote the vascular endothelial growth factor A (VEGFa)/vascular endothelial growth factor receptor 2 (VEGFR2)/extracellular signal-regulated protein kinase (ERK) pathway. The knockdown of RFC5 reduced CRC tumorigenesis in vivo. Collectively, these data demonstrate that the circ_0038985/miR-3614-5p/RFC5 axis plays a critical role in the progression of CRC, and RFC5 may promote CRC progression by affecting the VEGFa/VEGFR2/ERK pathway.

ZNF3 regulates proliferation, migration and invasion through MMP1 and TWIST in colorectal cancer.

Colorectal cancer (CRC) is a malignant tumor with a high incidence and mortality worldwide. Currently, the underlying molecular mechanisms of CRC are still unclear. Zinc finger protein 3 (ZNF3) is a zinc-finger transcription factor that has been reported as a candidate for breast cancer prognosis, suggesting its involvement in the regulation of tumorigenesis. However, the association between ZNF3 and CRC remains unknown. To investigate the role of ZNF3 in CRC, we first analyze the correlation between ZNF3 expression and CRC, and the results demonstrate that ZNF3 is highly expressed in CRC tissue and cells, which is associated with the age of CRC patients. In vitro studies show that ZNF3 overexpression promotes CRC cell migration. Compared to control cells, knockdown of ZNF3 markedly suppresses CRC cell proliferation, migration and invasion and promotes G0/G1 phase cell cycle arrest. The expressions of the EMT-related markers TWIST and MMP1 are significantly decreased when ZNF3 is silenced. Additionally, overexpression of MMP1 and TWIST exacerbates CRC cell proliferation, accelerates the S phase cell cycle in ZNF3-knockdown SW480 cells, and increases cell migration and invasion through Transwell chambers. These data suggest that ZNF3 is involved in cellular proliferation, migration and invasion by regulating MMP1 and TWIST in CRC cells.

Serum amyloid A1 recruits neutrophils to the invasive front of T1 colorectal cancers.

The tumor microenvironment plays an essential role in the development and progression of colorectal cancer (CRC). We recently reported that crosstalk between CRC cells and tumor-associated macrophages (TAMs) via serum amyloid A1 (SAA1) promotes invasion by T1 CRCs. In the present study, we aimed to clarify the role of neutrophils in early CRCs. Immunohistochemical analysis of CD66b, chemokine CXC motif ligand 8 (CXCL8 or interleukin-8, IL-8) and matrix metalloproteinase-9 (MMP-9) was performed using primary T1 CRCs (n=49). The HL-60 human promyelocytic leukemia cell line and THP-1 human monocytic leukemia cell line were used to obtain neutrophil-like and macrophage-like cells, respectively. Boyden chamber assays were used to analyze cell migration and invasion, and quantitative RT-PCR was used to analyze gene expression. Immunohistochemical analysis revealed accumulation of neutrophils at the SAA1-positive invasive front of T1 CRCs. Experiments using HL-60 cells suggested that treatment with SAA1 induced neutrophil migration and expression of CXCL8 and MMP-9 in neutrophils and that neutrophils promote CRC cell migration and invasion. Immunohistochemistry confirmed accumulation of CXCL8- or MMP-9-positive neutrophils at the SAA1-positive invasive front of T1 CRCs. Moreover, co-culture experiments using CRC, THP-1 and HL-60 cells suggested that CRC cells activated by macrophages upregulate CXCL8 and MMP-9 in neutrophils. Our results suggest that interplay between macrophages and CRC cells leads to recruitment of neutrophils to the invasive front of T1 CRCs and that SAA1 secreted by CRC cells activate neutrophils to promote invasion.

Extracellular vesicles from colorectal cancer cells promote metastasis via the NOD1 signalling pathway.

Pattern‐recognition receptors (PRRs) have been shown to promote tumour metastasis via sensing tumour cell‐derived small extracellular vesicles (EVs). Nucleotide‐binding oligomerisation domain 1 (NOD1), a cytoplasmic PRR, plays a role in colorectal cancer (CRC) by detecting bacterial products. However, the precise mechanisms underlying the effects of NOD1, following identification of CRC cell‐derived EVs (CRC‐EVs), to potentiate CRC liver metastasis (CRC‐LM), remain poorly understood. Here, we demonstrate that CRC‐EVs activate NOD1 in macrophages to initiate secretion of inflammatory cytokines and chemokines. NOD1‐activated macrophages also promote CRC cell migration, while in a murine model of liver metastasis (LM), NOD1‐deficient mice exhibit reduced metastasis following CRC‐EV treatment. Furthermore, cell division cycle 42 (CDC42), a small Rho guanosine‐5′‐triphosphate (GTP)ase, is delivered by CRC‐EVs into macrophages where it activates NOD1. In addition, EVs from the plasma of patients with CRC‐LM mediate NOD1 activation in human peripheral blood mononuclear cells. Moreover, high NOD1 expression in tumour tissues is associated with poor prognosis of CRC‐LM. Our findings suggest that CRC‐EVs activate NOD1 to promote tumour metastasis, thus, NOD1 may serve as a potential target in the diagnosis and treatment of CRC‐LM.

Tumor-associated macrophage-specific CD155 contributes to M2-phenotype transition, immunosuppression, and tumor progression in colorectal cancer

BackgroundOnco-immunogenic molecule CD155 is overexpressed in various tumor microenvironments (TME) including in colorectal cancer (CRC). Tumor-associated macrophages (TAMs) are the most abundant immune cells in CRC TME and play a...

ICAT promotes colorectal cancer metastasis via binding to JUP and activating the NF-κB signaling pathway.

BackgroundThe inhibitor of β‐catenin and T‐cell factor (ICAT) is a direct negative regulator of the canonical Wnt signaling pathway, which is an attractive therapeutic target for colorectal cancer (CRC). Accumulating evidence suggests that ICAT interacts with other proteins to exert additional functions, which are not yet fully elucidated.MethodsThe overexpression of ICAT of CRC cells was conducted by lentivirus infection and plasmids transfection and verified by quantitative real‐time reverse transcription‐polymerase chain reaction (real‐time RT‐PCR) and Western blotting. The effect of ICAT on the mobility of CRC cells was assessed by wound healing assay and transwell assay in vitro and lung metastasis in vivo. New candidate ICAT‐interacting proteins were explored and verified using the STRING database, silver staining, co‐immunoprecipitation mass spectrometry analysis (Co‐IP/MS), and immunofluorescence (IF) staining analysis.ResultInhibitor of β‐catenin and T‐cell factor overexpression promoted in vitro cell migration and invasion and tumor metastasis in vivo. Co‐IP/MS analysis and STRING database analyses revealed that junction plakoglobin (JUP), a homolog of β‐catenin, was involved in a novel protein interaction with ICAT. Furthermore, JUP downregulation impaired ICAT‐induced migration and invasion of CRC cells. In addition, ICAT overexpression activated the NF‐κB signaling pathway, which led to enhanced CRC cell migration and invasion.ConclusionInhibitor of β‐catenin and T‐cell factor promoted CRC cell migration and invasion by interacting with JUP and the NF‐κB signaling pathway. Thus, ICAT could be considered a protein diagnostic biomarker for predicting the metastatic ability of CRC.

ENO2 Promotes Colorectal Cancer Metastasis by Interacting with the LncRNA CYTOR and Activating YAP1-Induced EMT.

The glycolytic enzyme enolase 2 (ENO2) is dysregulated in many types of cancer. However, the roles and detailed molecular mechanism of ENO2 in colorectal cancer (CRC) metastasis remain unclear. Here, we performed a comprehensive analysis of ENO2 expression in 184 local CRC samples and samples from the TCGA and GEO databases and found that ENO2 upregulation in CRC samples was negatively associated with prognosis. By knocking down and overexpressing ENO2, we found that ENO2 promoted CRC cell migration and invasion, which is dependent on its interaction with the long noncoding RNA (lncRNA) CYTOR, but did not depend on glycolysis regulation. Furthermore, CYTOR mediated ENO2 binding to large tumor suppressor 1 (LATS1) and competitively inhibited the phosphorylation of Yes-associated protein 1 (YAP1), which ultimately triggered epithelial–mesenchymal transition (EMT). Collectively, these findings highlight the molecular mechanism of the ENO2–CYTOR interaction, and ENO2 could be considered a potential therapeutic target for CRC.

LncRNA GAL promotes colorectal cancer liver metastasis through stabilizing GLUT1.

Colorectal cancer liver metastasis (CRLM) is the leading cause of colorectal cancer-related deaths and remains a clinical challenge. Enhancement of glucose uptake is involved in CRLM; however, whether long noncoding RNAs (lncRNAs) participate in these molecular events remains largely unclear. Here, we report an lncRNA, GAL (glucose transporter 1 (GLUT1) associated lncRNA), that was upregulated in CRLM tissues compared with primary colorectal cancer (CRC) tissues or matched normal tissues and was associated with the overall survival rates of CRLM patients. Functionally, GAL served as an oncogene because it promoted CRC cell migration and invasion in vitro and enhanced the ability of CRC cells to metastasize from the intestine to the liver in vivo. Mechanistically, GAL interacted with the GLUT1 protein to increase GLUT1 SUMOylation, inhibiting the effect of the ubiquitin-proteasome system on the GLUT1 protein. GLUT1-knockout (-/+) repressed the GAL-mediated increase in CRC cell uptake of glucose, migrate, and invade in vitro, as well as metastasis from the intestine to the liver in vivo, and enforced expression of GLUT1 rescued GAL knockout-induced biological functions in CRC cells. Taken together, our findings demonstrated that GAL promotes CRLM by stabilizing GLUT1, suggesting that the GAL-GLUT1 complex may act as a potential therapeutic target for CRLM.

MICAL1 inhibits colorectal cancer cell migration and proliferation by regulating the EGR1/β-catenin signaling pathway

MICAL1 has been reported to be involved in the malignant processes of several types of cancer cells, however, the roles of MICAL1 in colorectal cancer (CRC) have not been well-characterized. This study aims to investigate the cellular functions and molecular mechanisms of MICAL1 in CRC cells. Here, we found that both mRNA and protein levels of MICAL1 were down-regulated in colorectal cancer tissues compared with matched adjacent non-tumor tissues, and the expression level of MICAL1 was correlated with the metastatic status of colorectal cancer. Importantly, overexpression of MICAL1 significantly inhibited colorectal cancer cell migration and growth, and increased the level of E-cadherin and Occludin, and suppressed the expression level of Vimentin and N-cadherin; while silencing of MICAL1 promoted CRC cell migration and enhanced EMT. In addition, MICAL1 overexpression significantly inhibited the proliferation and growth of CRC in vitro and in vivo. Moreover, RNA sequencing and bioinformatics analysis identified that MICAL1 was closely correlated with “cell migration”, “cell cycle” and “β-catenin signaling” genesets. Mechanistically, overexpression of MICAL1 downregulated the mRNA level of EGR1 and β-catenin, decreased the protein level and nuclear translocation of β-catenin, and inhibited the transcriptions of β-catenin downstream targets, c-myc and cyclin D1. The ectopic expression of EGR1 or β-catenin can significantly block the MICAL1-mediated inhibitory effects. Collectively, MICAL1 is down-regulated in CRC, and plays an inhibitory role in the migration and growth of CRC cells by suppressing the ERG1/β-catenin signaling pathway.

NFATc1 promotes epithelial-mesenchymal transition and facilitates colorectal cancer metastasis by targeting SNAI1

Metastatic recurrence remains a major cause of colorectal cancer (CRC) mortality. In this study, we investigated the mechanistic role of nuclear factor of activated T cells 1 (NFATc1) in CRC metastasis. First, we explored the potential role of NFATc1 in CRC using bioinformatics and hypothesized that NFATc1 might play different roles at different stages of CRC development. Then, we examined the relative expression of NFATc1 in 25 CRC tissues and adjacent normal tissues, and further analyzed the correlation between NFATc1 expression levels and clinical stages in 120 CRC patients. The role of NFATc1 in CRC metastasis and the molecular mechanisms were investigated in both in vitro and in vivo models. Our results showed that the expression of NFATc1 was increased in metastatic CRC tissues and positively associated with clinical stages (stage I vs. stage II, III or IV) of CRC. Overexpression of NFATc1 promoted CRC cell migration, invasion, and epithelial-mesenchymal transition (EMT). Moreover, SNAI1 was verified as the direct transcriptional target of NFATc1 and interacted with SLUG to promote EMT. Remarkably, our lung and liver metastasis mouse model demonstrated that NFATc1 overexpression accelerated CRC metastasis, and treatment with FK506, a calcineurin-NFAT pathway inhibitor, could suppress CRC metastasis in vivo. Taken together, our findings suggest that NFATc1 could transcriptionally activate SNAI1, which in turn interacts with SLUG to mediate EMT to promote CRC metastasis. Thus, making NFATc1 a promising therapeutic target in the treatment of metastatic CRC.

Tripartite Motif Protein 6 Promotes Colorectal Cancer Cell Migration and Metastasis via SOCS2-STAT3 Signaling.

Colorectal cancer (CRC) is one of the leading causes of cancer death worldwide, with most mortalities being caused by metastases. However, the underlying molecular mechanism of CRC metastases remains largely unknown. Emerging evidence has shown the role of the tripartite motif family, especially tripartite motif protein 6 (TRIM6), in carcinogenesis. In this study, we used CRC cell lines with TRIM6 knockdown and overexpression to investigate the function of TRIM6 in CRC metastasis. We found that TRIM6 promotes CRC cell migration and invasion both in vitro and in vivo. TRIM6 knockdown slows down the migration and invasion processes, whereas TRIM6 overexpression accelerates CRC cell migration and invasion. TRIM6 is potentially the upstream regulatory factor for signal transducer and activator of transcription 3 (STAT3) via the suppressor of cytokine signaling 2 (SOCS2). A total of 70 samples from patients with CRC further confirmed that TRIM6 expression level is positively correlated with STAT3 phosphorylation and negatively correlated with SOCS2 expression. Therefore, TRIM6 could be a potential therapeutic target for CRC metastasis.

The miR-106b/NR2F2-AS1/PLEKHO2 Axis Regulates Migration and Invasion of Colorectal Cancer through the MAPK Pathway.

Increasing numbers of miRNAs have been observed as oncogenes or tumor suppressors in colorectal cancer (CRC). It was recently reported that hsa-miR-106b-5p (miR-106b) promoted CRC cell migration and invasion. However, there were also studies showing contradictory results. Therefore, in the present study, we further explore the role of miR-106b and its downstream networks in the carcinogenesis of CRC. We observed that the expression of miR-106b is significantly increased in Pan-Cancer and CRC tissues compared with normal tissues from The Cancer Genome Atlas (TCGA) database. Furthermore, we used Transwell, Cell Counting Kit-8, and colony formation assays to clarify that miR-106b promotes the migratory, invasive, and proliferative abilities of CRC cells. For the first time, we systematically screened the target mRNAs and lncRNAs of miR-106b using TCGA database and the bioinformatics algorithms. Dual-luciferase reporter assay confirmed that NR2F2-AS1 and PLEKHO2 are the direct targets of miR-106b. Furthermore, NR2F2-AS1 acts as a competing endogenous RNA (ceRNA) to regulate PLEKHO2 expression by sponging miR-106b. The results of Gene set enrichment analysis (GSEA) and Western blot indicated that they play important roles in CRC progression by regulating MAPK pathway. Thus, miR-106b/NR2F2-AS1/PLEKHO2/MAPK signaling axis may suggest the potential usage in CRC treatment.

A Gene Expression Signature Predicting Colorectal Cancer Relapse Reveals LEMD1 as an Oncogenic Gene That Promotes CRC Cells Migration by RhoA/ROCK1 Signaling Pathway

Background: Colorectal cancer (CRC) experiencing early relapse consistently exhibited poor survival. However, an effective method for the diagnosis and prognosis of CRC postoperative relapse has not been developed. Methods: WGCNA analysis, RRA analysis and TNM staging difference analysis were conducted to screen the key genes in CRC dataset. The COX/LASSO regression model was used to construct CRC recurrence model in GSE33113. GSE39582 and TCGA database were used to further validate the diagnostic value of the model. The CCK8, Transwell and wound-healing assays were used to detect the biological function of LEMD1 in CRC cells. Rho GTPases pulldown experiment were conducted to investigate the mechanism by which LEMD1 promotes the activity of RhoA. Findings: a CRC relapse model composing of LEMD1, SERPINE1, and SIAE was constructed based on multiple datasets. The model was positively correlated with TNM stage and could be independent prognostic factor. Further in vitro experiments proved that LEMD1 could regulate CRC cell proliferation, migration, invasion and promote EMT transition. Specifically, we determined that LEMD1 promotes CRC cell migration through the RhoA/ROCK signaling pathway. Interpretation: We developed a CRC recurrence model which may be used to predict CRC recurrence early; LEMD1 may serve as a potential strategy for prevention and treatment in human CRC. Funding: This study was supported by Jiangsu Provincial Key Research Development Program (Grant/Award Number: BE2016794 and BE2016795). Declaration of Interest: The authors disclose no conflicts of interest. Ethical Approval: The study was carried out in accordance with the principles of the Helsinki Declaration and was approved by the Ethics Boards of Jiangsu Cancer Hospital.

MiR-224 targets BTRC and promotes cell migration and invasion in colorectal cancer

Our study aims to investigate the impact of miR-224 on cell migration and invasion in colorectal cancer (CRC) as well as its molecular mechanisms. The results showed that miR-224 was significantly upregulated in CRC compared to normal tissues via the TCGA database. Overexpression of miR-224 promoted CRC cell migration and invasion, while inhibition of miR-224 demonstrated the opposite result via transwell assays. In addition, we found that BTRC was a target gene of miR-224 through the miRecords database and dual-luciferase assay, while western blot together with RT-qPCR showed that inhibition of miR-224 led to elevated BTRC expression in protein level but not in mRNA level, and also decreased the expression of β-catenin. In reference to the Human Protein Atlas, BTRC protein expression was higher in normal tissues than in CRC tissues. In conclusion, miR-224 regulates its target BTRC protein expression and its related Wnt/β-catenin pathway. Its impact on cell migration and invasion in CRC cells suggested that miR-224 could be a prospective therapeutic target for early-stage non-metastatic CRC.

LncRNA SNHG11 facilitates tumor metastasis by interacting with and stabilizing HIF-1\u03b1

Epigenetic alteration is one of the hallmarks of colorectal cancer (CRC). Many driver genes are regulated by DNA methylation in CRC. However, the role of DNA methylation regulating lncRNAs remain elusive. Here, we identify that SNHG11 (small nucleolar RNA host gene 11) is upregulated by promotor hypomethylation in CRC and is associated with poor prognosis in CRC patients. SNHG11 can promote CRC cell migration and metastasis under hypoxia. Interestingly, the DNA-binding motif of SNHG11 is similar to that of HIF-1α. In addition, SNHG11-associated genes are enriched with members of the HIF-1 signaling pathway in CRC. Mechanistically, SNHG11 binds to the pVHLrecognition sites on HIF-1α, thus blocking the interaction of pVHL with HIF-1α and preventing its ubiquitination and degradation. Moreover, SNHG11 upregulates the expression of HIF-1α target genes, i.e., AK4, ENO1, HK2, and Twist1. Notably, SNHG11 can bind to the HRE sites in the promoter of these genes and increase their transcription. In summary, these results identify a SNHG11/ HIF-1α axis that plays a pivotal role in tumor invasion and metastasis.