Promotes Colorectal Cancer Progression Research Articles

Circular RNA ACACA negatively regulated p53-modulated mevalonate pathway to promote colorectal tumorigenesis via regulating miR-193a/b-3p/HDAC3 axis.

This study aimed to explore the biological functions and underlying mechanism of circRNA acetyl-CoA carboxylase alpha (circACACA) in colorectal cancer (CRC). The RNA and protein levels were detected by qRT-PCR and western blot assays. The malignant capacities of CRC cells were analyzed by cell counting kit-8 (CCK-8), colony formation, flow cytometry, and transwell assays. The target relationship between miR-193a/b-3p and circACACA/histone deacetylase 3 (HDAC3) was determined by luciferase reporter assay and RNA immunoprecipitation. The binding of HDAC3 to the p53 promoter was validated by chromatin immunoprecipitation (ChIP). CRC cell growth and lung metastasis were evaluated in nude mice in vivo. High expression of circACACA was found in CRC tissues and cells, which was closely associated with the advanced tumor, lymph node, metastasis (TNM) stage, metastasis, and low overall survival rate. circACACA downregulation effectively delayed CRC cell proliferation and metastasis, but triggered apoptosis via inactivating the mevalonic acid (MVA) pathway. However, circACACA overexpression resulted in the opposite effects. Mechanistically, circACACA enhanced HDAC3 expression through sponging miR-193a/b-3p, which activated theMVA pathway via inhibiting the acetylation and transcription of p53. Moreover, rescue experiments confirmed that miR-193a/b-3p inhibition reversed the inhibitory effect of circACACA deficiency on CRC growth and metastasis. Moreover, circACACA overexpression-mediated malignant phenotypes of CRC cells were abrogated by HDAC3 knockdown. circACACA promoted CRC progression via regulating themiR-193a/b-3p/HDAC3/p53 axis to activate theMVA pathway, providing evidence for circACACA as a promising therapeutic target for CRC.

Loss of exosomal miR-200b-3p from hypoxia cancer-associated fibroblasts promotes tumorigenesis and reduces sensitivity to 5-Flourouracil in colorectal cancer via upregulation of ZEB1 and E2F3.

Hypoxia-mediated tumor progression is a major clinical challenge in human cancers including colorectal cancer (CRC). In addition, exosome-mediated transfer of miRNAs from cancer-associated fibroblasts (CAFs) to cancer cells could promote tumor progression. However, the mechanisms by which hypoxia CAFs promotes CRC progression remain largely unknown. CAFs and normal fibroblasts (NFs) were isolated from CRC tissues and adjacent normal tissues. Next, exosomes were isolated from the supernatant of CAFs that cultured under normoxia (CAFs-N-Exo) and hypoxia (CAFs-H-Exo). RNA-sequencing was then performed to identify differentially expressed miRNAs (DEMs) between CAFs-N-Exo and CAFs-H-Exo. Compared with exosomes derived from normoxia CAFs, exosomes derived from hypoxic CAFs were able to promote CRC cell proliferation, migration, invasion, stemness and reduce the sensitivity of CRC cells to 5-fluorouracil (5-FU). In addition, miR-200b-3p levels were dramatically decreased in exosomes derived from hypoxic CAFs. Remarkably, increasing exosomal miR-200b-3p in hypoxic CAFs reversed the promoting effects of hypoxic CAFs on CRC cell growth in vitro and in vivo. Furthermore, miR-200b-3p agomir could inhibit CRC cell migration, invasion, stemness and increase the sensitivity of SW480 cells to 5-FU via downregulating ZEB1 and E2F3. Collectively, loss of exosomal miR-200b-3p in hypoxia CAFs could contribute to CRC progression via upregulation of ZEB1 and E2F3. Thus, increasing exosomal miR-200b-3p might serve as an alternative approach for the treatment of CRC.

Reprogramming of palmitic acid induced by dephosphorylation of ACOX1 promotes β-catenin palmitoylation to drive colorectal cancer progression

Metabolic reprogramming is a hallmark of cancer. However, it is not well known how metabolism affects cancer progression. We identified that metabolic enzyme acyl-CoA oxidase 1 (ACOX1) suppresses colorectal cancer (CRC) progression by regulating palmitic acid (PA) reprogramming. ACOX1 is highly downregulated in CRC, which predicts poor clinical outcome in CRC patients. Functionally, ACOX1 depletion promotes CRC cell proliferation in vitro and colorectal tumorigenesis in mouse models, whereas ACOX1 overexpression inhibits patient-derived xenograft growth. Mechanistically, DUSP14 dephosphorylates ACOX1 at serine 26, promoting its polyubiquitination and proteasomal degradation, thereby leading to an increase of the ACOX1 substrate PA. Accumulated PA promotes β-catenin cysteine 466 palmitoylation, which inhibits CK1- and GSK3-directed phosphorylation of β-catenin and subsequent β-Trcp-mediated proteasomal degradation. In return, stabilized β-catenin directly represses ACOX1 transcription and indirectly activates DUSP14 transcription by upregulating c-Myc, a typical target of β-catenin. Finally, we confirmed that the DUSP14-ACOX1-PA-β-catenin axis is dysregulated in clinical CRC samples. Together, these results identify ACOX1 as a tumor suppressor, the downregulation of which increases PA-mediated β-catenin palmitoylation and stabilization and hyperactivates β-catenin signaling thus promoting CRC progression. Particularly, targeting β-catenin palmitoylation by 2-bromopalmitate (2-BP) can efficiently inhibit β-catenin-dependent tumor growth in vivo, and pharmacological inhibition of DUSP14-ACOX1-β-catenin axis by Nu-7441 reduced the viability of CRC cells. Our results reveal an unexpected role of PA reprogramming induced by dephosphorylation of ACOX1 in activating β-catenin signaling and promoting cancer progression, and propose the inhibition of the dephosphorylation of ACOX1 by DUSP14 or β-catenin palmitoylation as a viable option for CRC treatment.

Has_circ_0071803 promotes colorectal cancer progression by regulating miR-330-5p/MAPK signaling pathway.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide. A lack of effective targeted therapies against CRC makes the treatment challenging. Here, we report a circular RNA (circRNA), has_circ_0071803, functioning as an oncogene in CRC. Circ_0071803 was upregulated in CRC tissues and cell lines, and its expression levels were inversely correlated with the prognosis and survival rate of patients with CRC. Circ_0071803 knockdown suppressed cell proliferation, migration, and invasion in CRC. Moreover, we found that circ_0071803 sponged miR-330-5p, thereby upregulating mitogen-activated protein kinase 1 (MAPK1) in CRC cells. The suppression of cell activities by circ_0071803 knockdown were rescued by miR-330-5p inhibition or MAPK1 overexpression. Collectively, our findings elucidate that circ_0071803 promotes CRC progression by regulating the miR-330-5p/MAPK1 pathway, providing potential therapeutic targets for designing effective targeted treatments.

LncRNA DICER1-AS1 promotes colorectal cancer progression by activating the MAPK/ERK signaling pathway through sponging miR-650.

Colorectal cancer (CRC) is a disease with high morbidity and mortality rates globally. Long noncoding RNAs (lncRNAs) play a fundamental role in tumor progression, and increasing attention has been paid to their role in CRC. This study aimed to determine the function of lncRNA DICER1 antisense RNA 1 (DICER1-AS1) in CRC and confirm its potential regulatory mechanisms in CRC. The publicly available dataset was used to assess DICER1-AS1 function and expression in CRC. RT-qPCR or western blot assays were performed to verify DICER1-AS1, miR-650, and mitogen-activated protein kinase 1 (MAPK1) expression in CRC cells or tissues. To determine the function of DICER1-AS1, we performed CCK-8, colony formation, transwell, cell cycle, and in vivo animal assays. Using RNA sequence analysis, luciferase reporter assays, and bioinformatics analysis, the connection between DICER1-AS1, MAPK1, and miR-650 was investigated. DICER1-AS1 was significantly upregulated in CRC tissue compared to normal colon tissue. High DICER1-AS1 expression suggested a poor prognosis in CRC patients. Functionally, upregulation of DICER1-AS1 effectively promoted CRC proliferation, migration, and invasion ex vivo and tumor progression in vivo. Mechanistically, DICER1-AS1 functions as a competitive endogenous RNA (ceRNA) that sponges miR-650 to upregulate MAPK1, promotes ERK1/2 phosphorylation, and sequentially activates the MAPK/ERK signaling pathway. Our investigations found that upregulation of DICER1-AS1 activates the MAPK/ERK signaling pathway by sponging miR-650 to promote CRC progression, revealing a possible clinically significant biomarker and therapeutic target.

(Pro)renin receptor promotes colorectal cancer progression through inhibiting the NEDD4L-mediated Wnt3 ubiquitination and modulating gut microbiota

BackgroundWe previously found that (pro)renin receptor ((P)RR) augments Wnt3 protein without affecting Wnt3 gene transcription in colorectal cancer (CRC) cells, thus contributes to CRC initiation. The present study aims to investigate whether (P)RR further promotes CRC progression following oncogenesis and the related mechanisms. Notably, we deeply elaborate how (P)RR affects Wnt3 protein level and the key enzyme that mediates this process.MethodsImmunohistochemistry, western blotting and immunofluorescence were performed to detect protein expression status. A kind of gastrointestinal epithelium-specific ATP6AP2 ((P)RR encoding gene) knock-in mice were generated using Crispr/Cas9 system.ResultsWe found that increased (P)RR expression in primary CRC lesions is positively associated with higher Wnt3 protein level and disease progression. Progressive CRC presents less colocalization of Wnt3 and an E3 ubiquitin ligase NEDD4L in primary lesions than non-progressive CRC. In colon cancer cells, (P)RR dramatically inhibits the NEDD4L-mediated Wnt3 protein ubiquitination. ATP6AP2 knock-in mice show more diminished Wnt3-NEDD4L colocalization in their gut epithelium in comparison to wildtype mice. They also have abnormal gut bacterial flora distribution. Especially, Lachnospiraceae_NK4A136 and Bacteroides genus, which are generally protective against CRC, are suppressed in guts of ATP6AP2 knock-in mice.ConclusionsCollectively, (P)RR promotes CRC progression through inhibiting the NEDD4L-mediated Wnt3 ubiquitination and modulating gut microbiota.5Fh7m3ebJHKpa3LjUnmMxGVideo

HECW2 promotes the progression and chemoresistance of colorectal cancer via AKT/mTOR signaling activation by mediating the ubiquitin-proteasome degradation of lamin B1.

Colorectal cancer (CRC) is among the most common malignancies worldwide. Although a recent study has shown that E3 ubiquitin ligases play a major role in regulating the occurrence and development of CRC, there are few reports on the role of the E3 ubiquitin ligase HECW2(HECT, C2 and WW domain containing E3 ubiquitin protein ligase 2) in CRC progression and chemoresistance. We found that HECW2 is highly expressed in CRC tissues. HECW2 knockdown inhibits CRC progression and chemoresistance, whereas HECW2 overexpression has the opposite effect. Mechanistically, HECW2 activates the AKT/mTOR signaling pathway by mediating the ubiquitin-proteasome degradation of lamin B1, thereby promoting CRC progression and chemoresistance. Our findings suggest that HECW2 may be a promising novel therapeutic target for CRC treatment.

The c-MYC-WDR43 signalling axis promotes chemoresistance and tumour growth in colorectal cancer by inhibiting p53 activity.

Oxaliplatin chemoresistance is a major challenge in the clinical treatment of colorectal cancer (CRC), which is one of the most common malignancies worldwide. In this study, we identified the tryptophan-aspartate repeat domain 43 (WDR43) as a potentially critical oncogenic factor in CRC pathogenesis through bioinformatics analysis. It was found that WDR43 is highly expressed in CRC tissues, and WDR43 overexpression is associated with poor prognosis of CRC patients. WDR43 knockdown significantly inhibits cell growth by arresting cell cycle and enhancing the effect of oxaliplatin chemotherapy both in vitro and in vivo. Mechanistically, upon oxaliplatin stimulation, c-MYC promotes the transcriptional regulation and expression of WDR43. WDR43 enhances the ubiquitination of p53 by MDM2 through binding to RPL11, thereby reducing the stability of the p53 protein, which induces proliferation and chemoresistance of CRC cells. Thus, the overexpression of WDR43 promotes CRC progression, and could be a potential therapeutic target of chemoresistance in CRC.

ANP32A Knockdown Attenuates the Malignant Biological Behavior of Colorectal Cancer Cells by Suppressing Epithelial-mesenchymal Transition and ERK Activation.

Acidic leucine rich nuclear phosphoprotein-32A (ANP32A) protein has a variety of functions, such as regulating cell differentiation, influencing cell apoptosis and cell cycle progression. Our previous study demonstrated that high expression of ANP32A was found in the tumor tissues of colorectal cancer (CRC) patients and was positively associated with tumor grading. However, the function and underlying mechanisms of ANP32A in CRC metastasis have not been fully explored. In this study, we found that ANP32A knockdown significantly attenuated the migration and invasion, and epithelial-mesenchymal transition (EMT) in cells. Further mechanistic studies revealed that ANP32A knockdown inhibited the expression of β-catenin and phosphorylated-ERK. The immunofluorescent staining experiment has revealed that ANP32A was expressed in the cell membrane, cytosol and nucleus, and its expression was positively associated with β-catenin expression levels. Moreover, the ability of cell migration and invasion was inhibited, the expression of E-cadherin was enhanced following ANP32A knockdown, and these affects were abolished by an ERK activator PMA, enhanced by an ERK inhibitor PD98059. Moreover, our animal experiment also demonstrated that silenced ANP32A inhibited CRC cell growth, multi-organ metastasis, ERK activation and EMT progression in vivo. Collectively, these findings demonstrated that ANP32A promotes CRC progression and that may be a promising target for the anti-metastasis treatment of CRC.

A Positive Feedback Loop of E2F4-Mediated Activation of MNX1 Regulates Tumour Progression in Colorectal Cancer.

Purpose: Colorectal cancer (CRC) is the 3rd most prevalent malignant tumour globally. Although significant strides have been made in diagnosis and treatment, its prognosis at the moment remains unpromising. Therefore, there is an urgent and desperate need to identify novel biomarkers of CRC and evaluate its mechanism of tumourigenesis and development. Methods: JASPAR and RNAinter databases are used to analyze target genes associated with colorectal cancer. Western blotting, q-PCR and immunohistochemistry et, al. were used to detect the level of MNX1 in patients with colorectal cancer, and Chip-PCR was used to detect the targeted binding ability of E2F4 and MNX1. The cells and animal models overexpressed MNX1 and E2F4 were constructed by shRNA transfection. Results: Herein, MNX1 was highly expressed and linked to favourable overall survival curves in colorectal cancer. The functional assay revealed that MNX1 overexpression could promote proliferation, migration, and invasion of CRC cells. Based on the prediction of the JASPAR and RNAinter databases, the transcription factor, E2F4, was bound to the MNX1 promoter region. The Chromatin Immunoprecipitation (ChIP) assay verified the interactions between MNX1 and E2F4 in CRC. Additionally, we found that sh-E2F4 markedly downregulated the MNX1 levels and reduced CRC progression in vivo and in vitro, which reversed MNX1 overexpression. Conclusion: Therefore, our research discovered that E2F4-mediated abnormal MNX1 expression promotes CRC progression and could become a novel diagnostic or therapeutic target of CRC.

Cancer-associated fibroblasts potentiate colorectal cancer progression by crosstalk of the IGF2-IGF1R and Hippo-YAP1 signaling pathways.

Colorectal cancer (CRC) is one of the most common cancers worldwide. The tumor microenvironment exerts crucial effects in driving CRC progression. Cancer-associated fibroblasts (CAFs) serve as one of the most important tumor microenvironment components promoting CRC progression. This study aimed to elucidate the novel molecular mechanisms of CAF-secreted insulin-like growth factor (IGF) 2 in colorectal carcinogenesis. Our results indicated that IGF2 was a prominent factor upregulated in CAFs compared with normal fibroblasts. CAF-derived conditioned media (CM) promoted tumor growth, migration, and invasion of HCT 116 and DLD-1 cells. IGF1R expression is significantly increased in CRC, serving as a potent receptor in response to IGF2 stimulation and predicting unfavorable outcomes for CRC patients. Apart from the PI3K-AKT pathway, RNA-seq analysis revealed that the YAP1-target signature serves as a prominent downstream effector to mediate the oncogenic signaling of IGF2-IGF1R. By single-cell RNA sequencing (scRNA-seq) and immunohistochemical validation, IGF2 was found to be predominantly secreted by CAFs, whereas IGF1R was expressed mainly by cancer cells. IGF2 triggers the nuclear accumulation of YAP1 and upregulates YAP1 target signatures; however, these effects were abolished by either IGF1R knockdown or inhibition with picropodophyllin (PPP), an IGF1R inhibitor. Using CRC organoid and in vivo studies, we found that cotargeting IGF1R and YAP1 with PPP and verteporfin (VP), a YAP1 inhibitor, enhanced antitumor effects compared with PPP treatment alone. In conclusion, this study revealed a novel molecular mechanism by which CAFs promote CRC progression. The findings highlight the translational potential of the IGF2-IGF1R-YAP1 axis as a prognostic biomarker and therapeutic target for CRC. © 2022 The Pathological Society of Great Britain and Ireland.

PRMT6 functionally associates with PRMT5 to promote colorectal cancer progression through epigenetically repressing the expression of CDKN2B and CCNG1

BackgroundProtein arginine methyltransferase 6 (PRMT6) is a type I arginine methyltransferase that asymmetrically dimethylates histone H3 arginine 2 (H3R2me2a). However, the biological roles and underlying molecular mechanisms of PRMT6 in colorectal cancer (CRC) remain unclear. MethodsPRMT6 expression in CRC tissue was examined using immunohistochemistry. The effect of PRMT6 on CRC cells was investigated in vitro and in vivo. Mass spectrometry, co-immunoprecipitation and GST pulldown assays were performed to identify interaction partners of PRMT6. RNA-seq, chromatin immunoprecipitation, Western blot and qRT-PCR assays were used to investigate the mechanism of PRMT6 in gene regulation. ResultsPRMT6 is significantly upregulated in CRC tissues and facilitates cell proliferation of CRC cells in vitro and in vivo. Through RNA-seq analysis, CDKN2B (p15INK4b) and CCNG1 were identified as new transcriptional targets of PRMT6. PRMT6-dependent H3R2me2a mark was predominantly deposited at the promoters of CDKN2B and CCNG1 in CRC cells. Furthermore, PRMT5 was firstly characterized as an interaction partner of PRMT6. Notably, H3R2me2a coincides with PRMT5-mediated H4R3me2s and H3R8me2s marks at the promoters of CDKN2B and CCNG1 genes, thus leading to transcriptional repression of these genes. ConclusionsPRMT6 functionally associates with PRMT5 to promote CRC progression through epigenetically repressing the expression of CDKN2B and CCNG1. These insights raise the possibility that combinational intervention of PRMT6 and PRMT5 may be a promising strategy for CRC therapy.

Fusobacterium nucleatum stimulates cell proliferation and promotes PD-L1 expression via IFIT1-related signal in colorectal cancer

Fusobacterium nucleatum (F. nucleatum) is enriched in colorectal cancer (CRC) tissues and a high amount of F. nucleatum was associated with an immunosuppressive tumor environment. PD-L1 is an important immune checkpoint expressed on tumor cells and promotes tumor immune escape. Whether PD-L1 is regulated by F. nucleatum is still unclear. We demonstrated that F. nucleatum promoted CRC progression and upregulated PD-L1 protein expression in CRC cell lines. Combined m6A-seq and RNA-seq identified m6A-modified IFIT1 mediating F. nucleatum induced PD-L1 upregulation. IFIT1 mRNA was modified with m6A modifications in 3’UTR and the m6A levels were altered by F. nucleatum treatment. Our results also indicated that IFIT1 served as a potential oncogene in CRC and regulated PD-L1 protein levels through altering PD-L1 ubiquitination. Clinical CRC data confirmed the correlation among F. nucleatum abundance, IFIT1 and PD-L1 expressions. Our work highlighted the function of F. nucleatum in stimulating PD-L1 expression through m6A-modified IFIT1 and provided new aspects for understanding F. nucleatum mediated immune escape.

SiRNA-based delivery nanoplatform attenuates the CRC progression via HIF1α-AS2

Colorectal cancer (CRC) is one of the most common malignancies and the leading causes of cancer-related deaths in the world. However, the molecular mechanisms of colorectal carcinogenesis and metastasis remain unknown. Long non-coding RNAs (lncRNAs) have been implicated to be in the initiation and malignant progression of CRC. In this study, we identified a novel oncogenic lncRNA HIF1α-AS2 in CRC patients by combination with lncRNA microarray and qRT-PCR. HIF1α-AS2 is upregulated progressively in adjacent non-tumor tissues to adenoma to CRC and contributes to CRC aggressive phenotypes. RNA-sequence assays and luciferase reporter assays were performed to reveal that upregulation of lncRNA HIF1α-AS2 may lead to the increased expression of HIF1α via competitively binding to miR-155–5p, miR-340–5p, miR-580–5p and miR-590–3p in CRC initiation, whereas HIF1α may work as a cellular sponge to directly interact with the RMRP promoter to promote RMRP transcription determined by chromatin immunoprecipitation and RNA-sequence assays. Data from RNA Binding Protein Immunoprecipitation and mass spectrometry revealed that RMRP-mediated an increased level of IGF2 expression promotes CRC progression and metastasis by competitively sponging IGF2R. Lastly, we developed mPEG-DSPE liposomes encapsulated with siRNA HIF1α-AS2, which exhibited desirable physicochemical properties along with narrow well-dispersion stability and significantly prevented the progression of CRC, indicating that mPEG-DSPE-liposome-encapsulated HIF1α-AS2 siRNA might be a potential biomarker and therapeutic target for CRC therapy.

SP1-induced PROX1-AS1 contributes to tumor progression by regulating miR-326/FBXL20 axis in colorectal cancer

Long noncoding RNAs (lncRNAs) play pivotal roles in cancers by regulating tumorigenesis and metastasis. LncRNA PROX1-AS1 has been reported to be involved in tumor progression, however, its role in colorectal cancer (CRC) remains ambiguous. Based on TCGA and GTEx databases, we found that the expression of PROX1-AS1 was upregulated in CRC tissues and cells. Bioinformatics analysis revealed that high PROX1-AS1 expression was associated with poor overall survival. Functionally, PROX1-AS1 knockdown suppressed CRC cell proliferation, migration, and invasion in vitro, as well as inhibiting tumor growth in vivo. Mechanistically, PROX1-AS1 was identified to act as a miR-326 sponge by luciferase reporter and RIP assay. Meanwhile, we found that the transcription factor SP1 activated PROX1-AS1/miR-32/FBXL20 axis, thereby promoting CRC progression. Our data demonstrated that PROX1-AS1 served as a promising prognostic biomarker for CRC, and the potential mechanism was unraveled.

Transcriptional factor III A promotes colorectal cancer progression by upregulating cystatin A

BACKGROUNDAdvanced colorectal cancer (CRC) generally has poor outcomes and high mortality rates. Clarifying the molecular mechanisms underlying CRC progression is necessary to develop new diagnostic and therapeutic strategies to improve CRC outcome and decrease mortality. Transcriptional factor III A (GTF3A), an RNA polymerase III transcriptional factor, is a critical driver of tumorgenesis and aggravates CRC cell growth.AIMTo confirm whether GTF3A promotes CRC progression by regulating the expression of cystatin A (Csta) gene and investigate whether GTF3A can serve as a prognostic biomarker and therapeutic target for patients with CRC.METHODSHuman tissue microarrays containing 90 pairs of CRC tissues and adjacent non-tumor tissues, and human tissue microarrays containing 20 pairs of CRC tissues, adjacent non-tumor tissues, and metastatic tissues were examined for GTF3A expression using immunohistochemistry. The survival rates of patients were analyzed. Short hairpin GTF3As and CSTAs were designed and packaged into the virus to block the expression of Gtf3a and Csta genes, respectively. In vivo tumor growth assays were performed to confirm whether GTF3A promotes CRC cell proliferation in vivo. Electrophoretic mobility shift assay and fluorescence in situ hybridization assay were used to detect the interaction of GTF3A with Csta, whereas luciferase activity assay was used to evaluate the expression of the Gtf3a and Csta genes. RNA-Sequencing (RNA-Seq) and data analyses were used to screen for target genes of GTF3A.RESULTSThe expression of GTF3A was higher in CRC tissues and lymph node metastatic tissues than in the adjacent normal tissues. GTF3A was associated with CRC prognosis, and knockdown of the Gtf3a gene impaired CRC cell proliferation, invasion, and motility in vitro and in vivo. Moreover, RNA-Seq analysis revealed that GTF3A might upregulate the expression of Csta, whereas the luciferase activity assay showed that GTF3A bound to the promoter of Csta gene and increased Csta transcription. Furthermore, CSTA regulated the expression of epithelial-mesenchymal transition (EMT) markers.CONCLUSIONGTF3A increases CSTA expression by binding to the Csta promoter, and increased CSTA level promotes CRC progression by regulating the EMT. Inhibition of GTF3A prevents CRC progression. Therefore, GTF3A is a potential novel therapeutic target and biomarker for CRC.

CXCL12/CXCR7/β-arrestin1 biased signal promotes epithelial-to-mesenchymal transition of colorectal cancer by repressing miRNAs through YAP1 nuclear translocation

BackgroundChemokine CXC motif receptor 7 (CXCR7) is an atypical G protein-coupled receptor (GPCR) that signals in a biased fashion. CXCL12/CXCR7 biased signal has been reported to play crucial roles in multiple stages of colorectal cancer (CRC). However, the mechanism of CXCL12/CXCR7 biased signal in promoting CRC progression and metastasis remains obscure.ResultsWe demonstrate that CXCR7 activation promotes EMT and upregulates the expression of Vimentin and doublecortin-like kinase 1 (DCLK1) in CRC cells with concurrent repression of miR-124-3p and miR-188-5p through YAP1 nuclear translocation. Cell transfection and luciferase assay prove that these miRNAs regulate EMT by targeting Vimentin and DCLK1. More importantly, CXCL12/CXCR7/β-arrestin1-mediated biased signal induces YAP1 nuclear translocation, which functions as a transcriptional repressor by interacting with Yin Yang 1 (YY1) and recruiting YY1 to the promoters of miR-124-3p and miR-188-5p. Pharmacological inhibitor of YAP1 suppresses EMT and tumor metastasis upon CXCR7 activation in vivo in tumor xenografts of nude mice and inflammatory colonic adenocarcinoma models. Clinically, the expression of CXCR7 is positively correlated with nuclear YAP1 levels and EMT markers.ConclusionsOur studies reveal a novel mechanism and clinical significance of CXCL12/CXCR7 biased signal in promoting EMT and invasion in CRC progression. These findings highlight the potential of targeting YAP1 nuclear translocation in hampering CXCL12/CXCR7 biased signal-induced metastasis of colorectal cancer.

Colorectal Cancer and Purinergic Signalling: An Overview.

Highlights What are the main findings? CD39-CD73 axis in tumor-associated immune cells promotes immune exhaustion, impairment of antitumor immune activity, and increased CRC progression.CD73 overexpression in cancer cells is associated with tumor growth, chemoresistance, and decreased patient survival.Extracellular ATP exhibits dual effects, either reducing tumor cell proliferation or favoring chemoresistance in a concentration-dependent fashion.Purinergic signaling components exhibit prognostic value and have the potential to be utilized as therapeutic targets. What is the implication of the main finding? CD73 induces colorectal cancer progression.CD39 contributes to immunosuppressive activity of T cells and poor prognosis.P2 and P1 purinoceptors were mainly associated with poor prognosis for patients.Ectonucleotidases and purinoceptors have potential as therapeutic targets in CRC. Simple SummaryColorectal cancer is a leading cause of cancer-related death. Activated immune cells have the potential to eliminate tumor cells, but cancers gain the ability to suppress immune cell functions and escape immune attack. We explored one mechanism that cancers use to evade immune cells in colorectal cancer. This mechanism alters levels of molecules known as purines. Purines are key players in cellular energetics and many cellular processes and can also lead to immune suppression in cancer. In this study, we reviewed the literature that identified specific enzymes (ectonucleoetidases) and receptors (purinoceptors) which alter the levels of purines and contribute to immunosuppression in colorectal cancer. We hope that targeting these enzymes and receptors can activate the immune response against colorectal cancer and halt cancer growth and progression.Colorectal cancer (CRC) is among the most common cancers and exhibits a high fatality rate. Gut inflammation is related to CRC, with loss of homeostasis in immune cell activities. The cells of the innate and adaptive immune system, including macrophages, neutrophils, mast cells, and lymphocytes, are present in most solid tumors. Purinergic signaling allows for communication between immune cells within the tumor microenvironment (TME) and can alter the TME to promote tumor progression. This system is regulated by the availability of extracellular purines to activate purinoceptors (P1 and P2) and is tightly controlled by ectonucleotidases (E-NPP, CD73/CD39, ADA) and kinases, which interact with and modify nucleotides and nucleosides availability. In this review, we compiled articles detailing the relationship of the purinergic system with CRC progression. We found that increased expression of CD73 leads to the suppression of effector immune cell functions and tumor progression in CRC. The P1 family purinoceptors A1, A2A, and A2B were positively associated with tumor progression, but A2B resulted in increased cancer cell apoptosis. The P2 family purinoceptors P2X5, P2X7, P2Y2, P2Y6, and P2Y12 were factors primarily associated with promoting CRC progression. In summary, CD39/CD73 axis and the purinergic receptors exhibit diagnostic and prognostic value and have potential as therapeutic targets in CRC.

MRGBP promotes colorectal cancer metastasis via DKK1/Wnt/β-catenin and NF-kB/p65 pathways mediated EMT

MRG domain binding protein (MRGBP) has been proposed to participate in the development of multiple tumors. However, the role of MRGBP in colorectal cancer (CRC) still remains largely unknown. Here, we found that MRGBP expression is significantly elevated in CRC, and that higher MRGBP expression correlates with poorer survival in CRC patients. Experiments in vivo and in vitro indicated that MRGBP promotes CRC cells proliferation, migration, invasion, epithelial-mesenchymal transition (EMT) and xenograft tumor growth. Mechanically, for one thing, we discovered that MRGBP suppresses DKK1 expression, thus further activating the Wnt/β-catenin pathway in CRC cells. For another, MRGBP also enhances acetylation of NF-kB/p65 pathway. Treatment with Wnt/β-catenin and NF-kB pathways inhibitors further confirmed the mediation of these two pathways in MRGBP-promoted CRC cell processes. In conclusion, these findings together suggest that MRGBP promotes CRC progression via DKK1/Wnt/β-catenin and NF-kB/p65 pathways mediated EMT, identifying MRGBP as a promising prognostic and therapeutic target for CRC.

CircPTK2 accelerates tumorigenesis of colorectal cancer by upregulating AKT2 expression via miR-506-3p.

With the rapid increase in its incidence in the last decade, colorectal cancer (CRC) is becoming one of the most life-threatening cancers. Circular RNA PTK2 (circPTK2) has multiple functions in oncogenesis, including in CRC. However, it remains elusive if circPTK2 also plays an important role in CRC malignancy. The levels of circPTK2, miR-506-3p, and AKT serine/threonine kinase 2 (AKT2) were measured by qPCR. The protein level of AKT2 was evaluated by western blotting assay. The proliferation, migration, and invasion of CRC cancer cells were evaluated by MTT, colony formation, wound-healing, and transwell assays. The interaction between circPTK2 and miR-506-3p and between miR-506-3p and AKT2 mRNA were verified by dual-luciferase reporter assay. The expressions of circPTK2 and AKT2 were elevated in CRC cells, with a concomitant reduction of miR-506-3p. The knockdown of circPTK2 suppressed the proliferation, migration, and invasion of CRC cells. CircPTK2 targeted miR-506-3p and negatively regulated its expression. Furthermore, miR-506-3p overexpression suppressed the CRC progression by downregulating the AKT2 expression. AKT2 overexpression or miR-506-3p inhibition restored the suppression of growth and invasiveness of CRC cancer cells caused by circPTK2 silencing. The circPTK2/miR-506-3p/AKT2 axis plays a novel and essential role in promoting CRC progression, providing potential targets for CRC therapeutic modality.