Inhibited Colorectal Cancer Cell Proliferation Research Articles

MAGI2-AS3 rs7783388 polymorphism contributes to colorectal cancer risk through altering the binding affinity of the transcription factor GR to the MAGI2-AS3 promoter.

BackgroundIt has been indicated that the single nuclear polymorphisms (SNPs) in the long noncoding RNA (lncRNA) have association with colorectal cancer (CRC) susceptibility.MethodsWe enrolled 1078 cases with CRC and 1175 age‐ and gender‐matched cancer‐free controls to explore whether the polymorphisms in MAGI2‐AS3 have associations with CRC risk. qRT‐PCR, expression quantitative trait loci (eQTL) analyses, dual‐luciferase reporter assay, chromatin immunoprecipitation (ChIP), flow cytometry, and transwell assays were performed to explore the specific mechanisms in which MAGI2‐AS3 rs7783388 variation influenced the tumorigenesis of CRC.ResultsSubjects carrying rs7783388 GG genotype presented a higher risk of CRC compared with the AG/AA genotypes. Mechanistically, we found that the functional genetic variant of rs7783388 A > G decreased binding affinity of transcription factor glucocorticoid receptor (GR) to the MAGI2‐AS3 promoter, resulting in decreased transcriptional activity that subsequently downregulated MAGI2‐AS3 expression. Furthermore, functional experiments elucidated that MAGI2‐AS3 overexpression suppressed CRC cell proliferation, migration, and invasion capacities, arrested cell cycle at G0/G1 phase, and promoted cell apoptosis.ConclusionTaken together, our study demonstrated that the potential function of MAGI2‐AS3 as a tumor suppressor for CRC, and the MAGI2‐AS3 rs7783388 polymorphism is associated with the increased susceptibility to CRC by altering the binding ability of GR to the MAGI2‐AS3 promoter.

Blocking histone methyltransferase SETDB1 inhibits tumorigenesis and enhances cetuximab sensitivity in colorectal cancer.

The histone methyltransferase SETDB1 catalyzes the addition of methyl groups to histone H3 at lysine 9, and upregulation of SETDB1 is associated with poor prognosis in cancer patients. Here, we describe how overexpression of SETDB1 contributes to colorectal cancer (CRC) tumorigenesis and drug resistance. We show that SETDB1 is upregulated in CRC, and its level correlates with poor clinical outcome. SETDB1 attenuation inhibits CRC cell proliferation Mechanistically, SETDB1 promotes cell proliferation by upregulating Akt activation. Further, SETDB1 is essential for the tumorigenic activity of Akt. Functional characterization revealed that inhibition of SETDB1 reduces cell growth in CRC resistant to targeted treatments in vitro and in vivo, KRAS-mutated CRC included. Taken together, our results indicate that SETDB1 is a major driver of CRC and may serve as a potential target for the treatment of KRAS-mutated CRC.

Long noncoding RNA ZFAS1 promoting small nucleolar RNA-mediated 2\u2032-O-methylation via NOP58 recruitment in colorectal cancer

BackgroundIncreasing evidence supports the role of small nucleolar RNAs (snoRNAs) and long non-coding RNAs (lncRNAs) as master gene regulators at the epigenetic modification level. However, the underlying mechanism of these functional ncRNAs in colorectal cancer (CRC) has not been well investigated.MethodsThe dysregulated expression profiling of lncRNAs-snoRNAs-mRNAs and their correlations and co-expression enrichment were assessed by GeneChip microarray analysis. The candidate lncRNAs, snoRNAs, and target genes were detected by in situ hybridization (ISH), RT-PCR, qPCR and immunofluorescence (IF) assays. The biological functions of these factors were investigated using in vitro and in vivo studies that included CCK8, trans-well, cell apoptosis, IF assay, western blot method, and the xenograft mice models. rRNA 2′-O-methylation (Me) activities were determined by the RTL-P assay and a novel double-stranded primer based on the single-stranded toehold (DPBST) assay. The underlying molecular mechanisms were explored by bioinformatics and RNA stability, RNA fluorescence ISH, RNA pull-down and translation inhibition assays.ResultsTo demonstrate the involvement of lncRNA and snoRNAs in 2′-O-Me modification during tumorigenesis, we uncovered a previously unreported mechanism linking the snoRNPs NOP58 regulated by ZFAS1 in control of SNORD12C, SNORD78 mediated rRNA 2′-O-Me activities in CRC initiation and development. Specifically, ZFAS1 exerts its oncogenic functions and significantly up-regulated accompanied by elevated NOP58, SNORD12C/78 expression in CRC cells and tissues. ZFAS1 knockdown suppressed CRC cell proliferation, migration, and increased cell apoptosis, and this inhibitory effect could be reversed by NOP58 overexpression in vitro and in vivo. Mechanistically, the NOP58 protein could be recognized by the specific motif (AAGA or CAGA) of ZFAS1. This event accelerates the assembly of SNORD12C/78 to allow for further guiding of 2′-O-Me at the corresponding Gm3878 and Gm4593 sites. Importantly, silencing SNORD12C or 78 reduced the rRNAs 2′-O-Me activities, which could be rescued by overexpression ZFAS1, and this subsequently inhibits the RNA stability and translation activity of their downstream targets (e.g., EIF4A3 and LAMC2).ConclusionThe novel ZFAS1-NOP58-SNORD12C/78-EIF4A3/LAMC2 signaling axis that functions in CRC tumorigenesis provides a better understanding regarding the role of lncRNA-snoRNP-mediated rRNAs 2′-O-Me activities for the prevention and treatment of CRC.

LncRNA SOCS2-AS1 inhibits progression and metastasis of colorectal cancer through stabilizing SOCS2 and sponging miR-1264

Abnormal expression of long noncoding RNA (lncRNA) is involved in human cancers, including colorectal cancer (CRC). However, their functional mechanism is largely unknown. In this study, we explored the roles of lncRNA SOCS2-AS1 in modulating CRC progression. We showed that SOCS2-AS1 was lowly expressed in CRC tissues and cells. SOCS2-AS1 downregulation predicted a poor prognosis in patients with CRC. SOCS2-AS1 overexpression significantly suppressed CRC cell proliferation, colony formation, EdU incorporation, cell-cycle, migration and invasion in vitro while SOCS2-AS1 knockdown led to an opposite phenotype. SOCS2-AS1 overexpression inhibited CRC growth and metastasis in vivo. Mechanistically, we discovered that SOCS2-AS1 was positively correlated with SOCS2 expression in CRC tissues. SOCS2-AS1 contributes to SOCS2 expression through restraining miR-1264. Additionally, we showed that SOCS2 silencing abrogated the suppressive effects of SOCS2-AS1 overexpression. Taken together, our results identified a novel regulatory loop in which SOCS2-AS1/miR-1264/SOCS2 axis suppresses CRC progression.

LncRNA KCNQ1OT1 knockdown inhibits colorectal cancer cell proliferation, migration and invasiveness via the PI3K/AKT pathway.

Colorectal cancer (CRC) is one of the most common primary malignancies worldwide. Numerous studies have demonstrated that long non-coding RNAs (lncRNAs) are considered as crucial regulators of tumor progression. In particular, upregulation of the lncRNA KCNQ1OT1 was reported in various types of malignancy as a promoter of tumor progression. However, the role and underlying mechanism of KCNQ1OT1 in CRC remain unclear. Thus, the present study aimed to investigate the role of KCNQ1OT1 in colorectal cancer through GEPIA, reverse transcription-quantitative PCR (RT-qPCR) and western blot analyses, and cell assays. GEPIA analysis demonstrated that high expression levels of KCNQ1OT1 in CRC tissues predicted a poor prognosis for patients with CRC. KCNQ1OT1 was overexpressed in CRC tissues and cell lines via RT-qPCR analysis. Furthermore, the results from the cell viability assay, colony formation assay, wound healing assay, invasion assay and flow cytometric analysis demonstrated that KCNQ1OT1 knockdown significantly inhibited CRC cell proliferation, migration and invasiveness, and promoted CRC cell apoptosis, leading to cell cycle arrest. Western blot analysis demonstrated that KCNQ1OT1 knockdown inhibited the PI3K/AKT signaling pathway. These results suggest that KCNQ1OT1 may act as an oncogene through the PI3K/AKT signaling pathway in CRC.

SETDB1 promotes the progression of colorectal cancer via epigenetically silencing p21 expression

SETDB1, a histone H3K9 methyltransferase, has been reported to be upregulated in a variety of tumors and promotes cancer development. However, the exact pathogenesis of SETDB1 in human colorectal cancer (CRC) is hitherto unknown. Here, we showed that SETDB1 expression was highly amplified in CRC. Functionally, SETDB1 downregulation in SW480 and HCT116 cells reduced cell proliferation, migration, invasion, and increased CRC cells apoptosis. In contrast, SETDB1 overexpression promoted CRC cells proliferation, migration, and invasion. High expression of SETDB1 was associated with a more aggressive phenotype in vitro. Flow cytometry showed that cell cycle was arrested in G1 phase after SETDB1 silencing. Furthermore, depletion of SETDB1 in vivo suppressed CRC cells proliferation. Mechanistically, p21 was identified as the target of SETDB1. After transfected with siSETDB1, expression of p21 was distinctly increased. In contrast, expression of p21 was significantly decreased after overexpression SETDB1. We also showed that SETDB1 could be involved in the regulation of epithelial–mesenchymal transition (EMT) in HCT116 cells. Moreover, we confirmed that SETDB1 could regulate the activity of p21 promoter by dual-luciferase repoter assay, and proved that SETDB1 could bind to the promoter of p21 and regulate its H3K9me3 enrichment level by ChIP-PCR experiment. Finally, we verified that silencing of SETDB1 inhibited CRC tumorigenesis in vivo. In conclusion, our results indicate that SETDB1 is a major driver of CRC development and might provide a new therapeutic target for the clinical treatment of CRC.

RFC2, a direct target of miR-744, modulates the cell cycle and promotes the proliferation of CRC cells.

Colorectal cancer (CRC) is a common digestive tract malignancy, which is characterized by high mortality, morbidity, and poor prognosis. Replication factor C subunit 2 (RFC2), oneRFC family member, was reported to be related to various malignancies and plays an important role in proliferation, invasion, and metastasis. Nonetheless, the RFC2 biological role within CRC is still unknown. RFC2 expression profiles in CRC tissues were collected based on The Cancer Genome Atlas database, whereas miR-744 and RFC2 expression levels were detected in human CRC tissues. miR-744 and RFC2 effects on the proliferation of CRC were assessed both in vivo and in vitro. RFC2 was recognized to be a direct miR-744 target through luciferase reporter assay. RFC2 upregulation was observed within CRC tissues, and a high RFC2 level showed a correlation with poor clinicopathological symptoms. RFC2 knockdown inhibited CRC cell proliferation through promoting cell cycle arrest at the G1 phase, which was achieved by cyclin E2 (CCNE2) downregulation in vivo and in vitro. miR-744 was identified to be the tumor suppressor microRNA, which targeted RFC2 directly for inhibiting the proliferation of CRC cells both in vivo and in vitro. miR-744 downregulation was detected within CRC tissue, and messenger RNA expression showed a negative correlation with RFC2 expression within CRC tissues. Our study demonstrates that the miR-744/RFC2/CCNE2 axis potentially provides a candidate for a treatment strategy for CRC.

MicroRNA-493-5p suppresses colorectal cancer progression via the PI3K-Akt-FoxO3a signaling pathway.

MicroRNA493-5p (miR-493-5p) appears to have an essential role in the abnormal cell proliferation and migration observed in the development and progression of various cancers. However, the function and mechanism of action of miR-493-5p in colorectal cancer (CRC) is unclear. MiR-493-5p expression was analyzed in CRC patient tissue samples and cell lines by fluorescence quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). SW480 and Caco-2 cells were transfected with miR-493-5p mimics or treated with the phosphoinositide 3-kinase (PI3K) agonist 740Y-P. Cell proliferation was determined by colony formation and cell proliferation assays and cell migration and invasion by transwell migration and wound-healing assays. The Luciferase reporter assay was used to verify the association between the expression of miR-493-5p and PI3K activity. Expression levels of PI3K, protein kinase B(Akt), and forkhead box O 3a (FoxO3a) proteins were measured by Western blot analysis and immunofluorescence assay. MiR-493-5p expression was significantly downregulated in CRC tissue samples and cell lines which was associated with progression of CRC. The proliferation, migration, and invasion of CRC cells were inhibited by miR-493-5p overexpression. The finding that miR-493-5p upregulation decreased PI3K, Akt, and FoxO3a protein expression revealed that it directly targets PI3K. Additionally, the miR-493-5p-mediated suppression of CRC cell proliferation, migration and invasion was counteracted by the PI3K agonist, indicating that miR-493-5p suppresses CRC progression by inhibiting the PI3K-Akt-FoxO3a signaling pathway. MiR-493-5p suppresses the proliferation, migration, invasion, and progression of CRC via the PI3K-Akt-FoxO3a signaling pathway.

SIRT2-dependent IDH1 deacetylation inhibits colorectal cancer and liver metastases.

Protein lysine acetylation affects colorectal cancer (CRC) distant metastasis through multiple pathways. In a previous proteomics screen, we found that isocitrate dehydrogenase 1 (IDH1) is hyperacetylated in CRC primary tumors and liver metastases. Here, we further investigate the function of IDH1 hyperacetylation at lysine 224 in CRC progression. We find that IDH1 K224 deacetylation promotes its enzymatic activity and the production of α-KG, and we identify sirtuin-2 (SIRT2) as a major deacetylase for IDH1. SIRT2 overexpression significantly inhibits CRC cell proliferation, migration, and invasion. IDH1 acetylation is modulated in response to intracellular metabolite concentration and regulates cellular redox hemostasis. Moreover, IDH1 acetylation reversely regulates HIF1α-dependent SRC transcription which in turn controls CRC progression. Physiologically, our data indicate that IDH1 deacetylation represses CRC cell invasion and migration invitro and invivo, while the hyperacetylation of IDH1 on K224 is significantly correlated to distant metastasis and poor survival of colorectal cancer patients. In summary, our study uncovers a novel mechanism through which SIRT2-dependent IDH1 deacetylation regulates cellular metabolism and inhibits liver metastasis of colorectal cancer.

MiR-203 Regulates Proliferation and Apoptosis of Colorectal Cancer Cells Through Targeting DJ-1

Objective: To assess whether miR-203 regulates DJ-1 expression, affects colorectal cancer cells through PTEN-PI3K/AKT signaling. Methods: Colorectal cancer (CRC) tissues and adjacent tissues were collected followed by analysis of the level of miR-203, DJ-1 and PTEN. miR-203 and DJ-1 level was measured in HCT116, SW480 and normal colorectal cell NCM460. miR-203 mimic or miR-NC was transfected into HCT116 or SW480 cells followed by measuring the level of miR-203, DJ-1, PTEN, p-AKT as well as cell apoptosis and proliferation. Results: Compared with tumor adjacent tissues, tumor tissues showed significantly lower level of miR-203 and PTEN, and higher level of DJ-1. There is a targeted relationship between miR-203 and DJ-1. Compared with NCM460 cell, HCT116 and SW480 cells displayed significantly lower miR-203 level and higher DJ-1 expression. miR-203 mimic significantly reduced DJ-1 and p-AKT level, increased PTEN expression, cell apoptosis and inhibited cell proliferation. Conclusion: Lower miR-203 and higher DJ-1 level is found in CRC patients. Upregulation of miR-203 inhibits DJ-1 expression, increases PTEN expression, impairs PI3K/AKT signaling, inhibits CRC cell proliferation and promotes apoptosis.

Omega-3PUFA Attenuates MNU-Induced Colorectal Cancer in Rats by Blocking PI3K/AKT/Bcl-2 Signaling.

BackgroundOmega 3 polyunsaturated fatty acid (Omega-3PUFA) is one of the essential nutrients for human body involved in intracellular metabolic regulation and cell signaling. Previous studies have shown that Omega-3PUFA is involved in the pathogenesis of digestive system tumors, including colorectal cancer (CRC), however, the effects of Omega-3PUFA on CRC has not been fully elucidated. In the current study, we evaluated whether Omega-3PUFA can alleviate N-methyl-N-nitrosourea(MNU) induced CRC in a rat model and illustrated the potential mechanism.MethodsThe effects of Omga-3PUFA on MNU-induced colorectal cancer in rats were analyzed by in vivo experiments. The viability, apoptosis, colony formation and invasion of CRC cells treated with Omga-3PUFA were detected by CCK8, flow cytometry, clone formation assay and transwell invasion assay. The expression of apoptosis-related proteins in CRC cells treated with Omga-3PUFA was detected by Western blotting. Finally, after adding PI3K activator, the viability, apoptosis and protein expression of CRC cells treated with Omga-3PUFA were detected by CCK8, flow cytometry and Western blotting.ResultsOur results showed that Omega-3PUFA attenuated MNU-induced CRC in rats and inhibited AKT/Bcl-2 signaling in rats. In addition, Omega-3PUFA inhibited CRC cell proliferation and induces CRC cell apoptosis. Moreover, Omega-3PUFA inhibited CRC cell colony formation and invasion, and inhibited PI3K/AKT/Bcl-2 signaling in CRC cells. Furthermore, The effects of Omega-3PUFA on cell proliferation and apoptosis were inhibited by blocking PI3K/AKT signaling.ConclusionOmega-3PUFA can attenuate MNU-induced colorectal cancer in rats by blocking PI3K/AKT/Bcl-2 signaling, which suggests that Omega-3PUFA may be a potent agent for CRC treatment.

LncRNA FTX Contributes to the Progression of Colorectal Cancer Through Regulating miR-192-5p/EIF5A2 Axis.

BackgroundLong non-coding RAN five prime to Xist (LncRNA FTX) has been revealed to be a cancer-related lncRNA and implicated in the progression of colorectal cancer (CRC). Besides, miR-192-5p (miR-192) or eukaryotic initiation factor 5A2 (EIF5A2) also was identified to link with the tumorigenesis of CRC. Here, we further explored the function of FTX and the regulatory relationship among FTX, miR-192 and EIF5A2 in CRC progression.MethodsLevels of FTX, miR-192-5p and EIF5A2 were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or Western blot, respectively. Cell proliferation, apoptosis, migration and invasion were analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry or transwell assay, respectively. The interaction between miR-192-5p and FTX or EIF5A2 was confirmed by dual-luciferase reporter and pull-down assay. Murine xenograft model was established using LoVo cells transfected with sh-FTX.ResultsFTX was up-regulated in CRC tissues and cell lines, knockdown of FTX inhibited CRC cell proliferation, migration and invasion in vitro as well as suppressed CRC tumor growth in vivo. FTX was confirmed to directly bind to miR-192-5p and negatively regulated miR-192-5p expression in CRC cells. Besides that overexpressed FTX positively modulated EIF5A2, a direct target of miR-192-5p, via miR-192-5p in CRC cells. Importantly, the inhibitory activities on CRC progression mediated by FTX deletion were reversed miR-192-5p down-regulation or EIF5A2 up-regulation.ConclusionLncRNA FTX functioned as an oncogene to contribute to CRC progression by regulating miR-192-5p/EIF5A2 axis, providing a novel insight into the pathogenesis of CRC and a promising therapeutic target for CRC treatment.

Long Non-coding RNA MIR4435-2HG Promotes Colorectal Cancer Proliferation and Metastasis Through miR-206/YAP1 Axis.

Objective: Long non-coding RNAs (lncRNAs) are critical to colorectal cancer (CRC) progression. In the current study, the objective was the exploration of the role played by lncRNA MIR4435-2HG in CRC proliferation and metastasis.Methods: lncRNA MIR4435-2HG expression and its association with CRC were analyzed using database and clinical specimens. The influences exerted by MIR4435-2HG on cell proliferating process, invading process, and migrating process of CRC were identified after MIR4435-2HG knockdown. The influences exerted by MIR4435-2HG on tumor growth and metastasis were assessed in vivo. The underlying mechanistic associations between MIR4435-2HG, microRNA miR-206, and the transcription factor Yes-associated protein 1 (YAP1) were assessed using bioinformatics and a luciferase reporter gene assay.Results: MIR4435-2HG was highly expressed in CRC tissue in contrast with that in regular tissues and displayed relations to poor prognosis. MIR4435-2HG knockdown could suppress CRC cell proliferation, invasion, and migration. Moreover, MIR4435-2HG knockdown inhibited CRC growth and liver metastasis in vitro. We found MIR4435-2HG knockdown reduced YAP1, CTGF, AREG, vimentin, Snail, Slug, and Twist expression but enhanced E-cadherin expression. Functionally, MIR4435-2HG acted as a competing endogenous RNA (ceRNA) to upregulate YAP1 by sponging miR-206.Conclusions: MIR4435-2HG promoted CRC growth and metastasis through miR-206/YAP1 axis and is likely to play prognostic marker roles and be therapeutically targeted in CRC.

Atractylenolide I inhibits colorectal cancer cell proliferation by affecting metabolism and stemness via AKT/mTOR signaling

BackgroundAtractylenolide I (ATL-1) is a natural herbal compound used in traditional Chinese medicine that has exhibited anti-cancer properties. The anti-tumorigenic activity of ATL-1 against colorectal cancer (CRC) and the underlying signaling pathways involved in its mechanisms are examined here. HypothesisATL-1 exerts therapeutic effect against CRC by disrupting glucose metabolism and cancer stem cell maintenance via AKT/mTOR pathway regulation. Study designIn vitro studies were performed in COLO205 and HCT116 CRC cell lines and in vivo studies were conducted in a mouse xenograft model of CRC tumor. MethodsCRC cells were treated with ATL-1 at various concentrations, with or without inhibitors of AKT or mTOR. Cell proliferation, apoptosis, invasion, stemness maintenance, glucose metabolism, and AKT/mTOR signaling were evaluated. CRC tumor-xenografted mice were treated with an AKT inhibitor and/or ATL-1, and glucose metabolism and stemness maintenance were examined in tumor tissues. ResultsATL-1 significantly inhibited the invasion of CRC cells by inducing their apoptosis, possibly via the excessive production of reactive oxygen species. Glucose metabolism (Warburg effect) was also altered and stem-like traits were suppressed by ATL-1. In addition, ATL-1 effectively acted as an inhibitor or AKT/mTOR by downregulating the phosphorylation of proteins related to the AKT/mTOR pathway. In vivo studies showed that tumor weight and volume were reduced by ATL-1 and that aerobic glycolysis, stemness maintenance, and AKT/mTOR activation were impaired by ATL-1 in colorectal tumors. ConclusionsATL-1 acts as an effective agent to suppress colorectal tumor progression, mainly by inhibiting CRC cell proliferation through altering apoptosis, glucose metabolism, and stem-like behavior. These processes were mediated by the AKT/mTOR signaling pathway both in vitro and in vivo. ATL-1 may be a potential agent to be used in molecular-targeted strategies for cancer treatment.

TRIM6 promotes colorectal cancer cells proliferation and response to thiostrepton by TIS21/FoxM1

BackgroundTripartite motif-containing proteins (TRIM) play a crucial role in carcinogenesis. Little attention has been focused on the possible functions of TRIM6 on carcinogenesis.MethodsThe expression levels of TRIM6 were assessed in colorectal cancer (CRC) samples. TRIM6 expression was knocked down in CRC cell lines, and subjected to Cell counting kit-8 (CCK-8), bromodeoxyuridine (BrdU) incorporation and cell cycle assays. Immunoprecipitation and proteomics analysis was performed to identify potential associated proteins of TRIM6.ResultsTRIM6 expression was up-regulated in CRC samples and TRIM6 expression may be an independent prognostic marker for CRC. Knocking down TRIM6 expression suppressed CRC cell proliferation, induced cell cycle arrested at G2/M phase and increased sensitivity to 5-fluorouracil and oxaliplatin. TIS21, an anti-proliferative protein involved in the regulation of G2/M arrest, was identified as an interaction partner of TRIM6. Moreover, CRC cells with TRIM6 overexpression showed decreased TIS21 protein stability. TIS21 ubiquitination was increased in CRC cells overexpressing TRIM6, but not in those overexpressing TRIM6 E3 catalytic mutant (C15A). Further, Lys5 was essential for TRIM6 mediated TIS21 ubiquitination. TIS21 overexpression reversed the induced effects of TRIM6 overexpression on CRC cell proliferation, and the levels of forkhead box M1 (FoxM1), phosphorylated FoxM1, Cyclin B1 and c-Myc. Thiostrepton, a specific inhibitor for FoxM1, was less effective in anti-proliferative activity against CRC cells with lower level of TRIM6 in vitro and in vivo.ConclusionsOur study suggests that TRIM6 promotes the progression of CRC via TIS21/FoxM1.

MiR-485-5p as a potential biomarker and tumor suppressor in human colorectal cancer.

Aim: To investigate the role of miR-485-5p in colorectal cancer (CRC). Methodology: The level of miR-485-5p in serum and cell lines were measured by quantitative real-time polymerase chain reaction, and analyzed the diagnostic and prognostic value. Additionally, the biological effect of miR-485-5p on CRC cells was also explored in vitro. Results: The receiver operating characteristic (ROC) curves analysis revealed that miR-485-5p was a diagnostic candidate. Kaplan-Meier analyses demonstrated that patients with low serum miR-485-5p had shorter overall survival. In addition, the result of cox regression model indicated that miR-485-5p was not an independent risk factor for progression. Functional study revealed that overexpression of miR-485-5p could inhibit CRC cell proliferation, invasion and facilitates cell apoptosis. Conclusion: Our study revealed that miR-485-5p was a tumor suppressor and it could serve as a potential prognostic biomarker in CRC.

Mechanisms of Colorectal Cancer Cell Growth and Metastasis Inhibition By Carp-1 Functional Mimetic-4

Introduction: Colorectal cancer (CRC) constitutes one of the most aggressive malignancies worldwide and in Malaysia. Due to high recurrence rate and toxic side effects associated with radiation and chemotherapies, new agents are urgently needed. CARP-1 is a peri-nuclear phospho-protein which plays a dynamic role in regulating cell growth and apoptosis. CARP-1 functional mimetics (CFMs) are a class of compounds that stimulate CARP-1. CFM-4, a lead compound, was shown to suppress growth and metastasis of various cancers, other than CRC. We hypothesized that CFM-4 inhibits proliferation and metastasis in CRC. Materials and method: CFM-4 anti-cancer effects of on CRC cells were investigated using MTT assay, Annexin V/Propidium iodide (PI) apoptosis assay, cell cycle analysis, quantitative real-time PCR (qRT-PCR) and Western blotting. Antimetastatic activities were assessed by migration, colony formation and invasion assays. Results: CFM-4 inhibited CRC cell proliferation and was much more potent than the classical anti-CRC 5-fluorouracil. These effects were shown to be mediated at least in part by stimulating apoptosis, as indicated in our Annexin V/PI assay results. Cell cycle analysis showed that CFM-4 induced G2/M phase arrest. Molecularly, qRT-PCR results revealed that CFM-4 promoted intrinsic apoptosis by upregulating expression of caspase-8 and -9 , p53, PUMA and Noxa, and stimulated extrinsic apoptosis by enhancing expression of death receptors (DR4 and DR5). CFM-4 upregulated NF- k B signaling inhibitor A20-binding inhibitor protein and the PI3K negative regulator PTEN. Western blot analysis results revealed that CFM-4 enhanced expression of CARP1, caspase-8 and executioner caspase-3. Metastatic properties of the CRC cells were reduced by CFM-4 through blocking their capabilities to form colonies, migrate and invade through the matrix-coated membranes. Conclusion: The potent antitumor and anti-metastatic properties of CFM-4 against CRC are due to collective pro-apoptotic, anti-proliferative and anti-metastatic activities. Together our data warrants further investigations of CFM-4 as potential anti-tumor agent for CRC malignancy and metastasis.

Synergistic antitumor effect of 5-fluorouracil with the novel LSD1 inhibitor ZY0511 in colorectal cancer.

Background:Lysine-specific histone demethylase 1 (LSD1) is a potential target of cancer therapy. In the present study, we aimed to investigate the combined antitumor activity of a novel LSD1 inhibitor (ZY0511) with 5-fluorouracil (5-FU) and elucidate the underlying mechanism in colorectal cancer (CRC).Methods:We evaluated LSD1 expression in CRC tissues from patients who received 5-FU treatment. The synergistic antitumor effect of 5-FU with ZY0511 against human CRC cells was detected both in vitro and in vivo. The underlying mechanism was explored based on mRNA sequencing (mRNA-seq) technology.Results:Overexpression of LSD1 was observed in human CRC tissues, and correlated with CRC development and 5-FU resistance. ZY0511, a novel LSD1 inhibitor, effectively inhibited CRC cells proliferation, both in vitro and in vivo. Notably, the combination of ZY0511 and 5-FU synergistically reduced CRC cells viability and migration in vitro. It also suppressed Wnt/β-catenin signaling and DNA synthesis pathways, which finally induced apoptosis of CRC cells. In addition, the combination of ZY0511 with 5-FU significantly reduced CRC xenograft tumor growth, along with lung and liver metastases in vivo.Conclusions:Our findings identify LSD1 as a potential marker for 5-FU resistance in CRC. ZY0511 is a promising candidate for CRC therapy as it potentiates 5-FU anticancer effects, thereby providing a new combinatorial strategy for treating CRC.

Evaluation of Potential of Long Noncoding RNA NEAT1 in Colorectal Cancer.

Long noncoding RNAs (lncRNAs) have been reported to be involved in cancer initiation and evolution, including colorectal cancer (CRC). Nuclear-enriched abundant transcript 1 (NEAT1) exerts important functions in multiple cancers; however, the specific modulatory mechanism in CRC demands in-depth exploration. The expression levels of NEAT1, microRNA-195-5p (miR-195-5p), and centrosomal protein 55 (CEP55) were examined using quantitative real-time polymerase chain reaction (qRT-PCR), and protein expression of CEP55 was detected by Western blot assay. Cell proliferation and apoptosis were measured by 3-(4,5-dimethylthiazole-2-y1)-2,5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry. Transwell migration and invasion assays were applied to evaluate cell metastasis ability. Dual-luciferase reporter assay was used to analyze the correlation among NEAT1, miR-195-5p and CEP55. The expression of NEAT1 was up-regulated in CRC tissues and cells, and overall survival was lower with high expression of NEAT1. Knockdown of NEAT1 repressed cell proliferation, migration, and invasion, while inducing apoptosis in CRC cells. NEAT1 targeted miR-195-5p and inhibited the expression of miR-195-5p. Silence of NEAT1 inhibited CRC cell proliferation, migration, and invasion, and promoted apoptosis by up-regulating miR-195-5p. MiR-195-5p targeted and suppressed CEP55 expression, and CEP55 reverted the effects induced by miR-195-5p. NEAT1 regulated the expression of CEP55 through miR-195-5p. NEAT1 promotes colorectal cancer cellular processes by regulating CEP55 expression via the sponging of miR-195-5p. Therefore, NEAT1 might play a crucial role in CRC treatments.

Propofol suppresses proliferation and metastasis of colorectal cancer cells by regulating miR-124-3p.1/AKT3.

Propofol, an extensively used intravenous anesthetic agents during cancer resection surgery, has been confirmed to execute anti-tumor effect on multiple cancers, including colorectal cancer (CRC). Although the role of propofol in CRC has been previously reported, its action mechanism remains poorly understood. This study further explored the biological function and underlying mechanism of propofol in CRC cells. The cell proliferation, migration and invasion were assessed by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay, wound healing assay and transwell assay, respectively. The expression levels microRNA-124-3p.1 (miR-124-3p.1) and AKT serine/threonine kinase 3 (AKT3) was analyzed by quantitative real-time polymerase chain reaction. Western blot assay was employed to measure the protein expression of MMP-9, Vimentin and Cyclin D1. The interaction between miR-124-3p.1 and AKT3 was predicted by TargetScan and confirmed by dual-luciferase reporter assay. Propofol inhibited CRC cell proliferation, migration and invasion. Knockdown of miR-124-3p.1 or AKT3 upregulation reversed the inhibitory effects of propofol on CRC cell proliferation and metastasis. Besides, AKT3 was a direct target of miR-124-3p.1 and its overexpression abated the anti-tumor effect of miR-124-3p.1 on CRC cell proliferation and metastasis. Propofol inhibited CRC cell proliferation, migration and invasion by upregulating miR-124-3p.1 and downregulating AKT3, providing a new sight for propofol treatment of CRC.