Molecular Mechanisms Of Colorectal Cancer Research Articles

SLC25A19 drives colorectal cancer progression by regulating p53.

Investigating the molecular mechanism of colorectal cancer (CRC), a common lethal malignancies worldwide, is of great clinical significance. Solute carrier family 25 member 19 (SLC25A19) is a member of the solute carrier family that contribute to cellular functions, including tumor biology. Recently, many studies have attention on uncovering the relationship of SLC25A19 with malignant cancers, but its precise involvement in the regulation of CRC has not been thoroughly understood. This study sought to uncover the role and mechanism of SLC25A19 in CRC development. The GEPIA database and immunohistochemical staining were utilized to detect the expression of SLC25A19 in CRC tissues. The functional influences of SLC25A19 on CRC cell phenotypes were evaluated through a series of assays including celigo cell count, colony formation, CCK-8, flow cytometry, wound healing, and transwell assays following knocking down SLC25A19. Subsequently, the xenograft tumor model was constructed to evaluate the effect of SLC25A19 on tumor growth invivo. The underlying mechanisms of SLC25A19 silencing were investigated using the human phospho-kinase array. This study demonstrated the upregulation of SLC25A19 in CRC and its significant correlation with unfavorable prognosis in CRC patients. Suppression of SLC25A19 resulted in significant inhibition of cell proliferation, colony formation, and cell migration, alongside a boost in cell apoptosis. Invivo experiments revealed that silenced SLC25A19 displayed reduced growth rates and formed smaller xenografts. Mechanistically, the p53 pathway was found to be upregulated by SLC25A19 knockdown and mediated the function of SLC25A19. Consequently, SLC25A19 was identified as a novel molecule with key regulatory ability in CRC development.

LINC00460/miR-186-3p/MYC feedback loop facilitates colorectal cancer immune escape by enhancing CD47 and PD-L1 expressions

BackgroundLong non-coding RNAs (LncRNAs) have been implicated as critical regulators of cancer tumorigenesis and progression. However, their functions and molecular mechanisms in colorectal cancer (CRC) still remain to be further elucidated.MethodsLINC00460 was identified by differential analysis between human CRC and normal tissues and verified by in situ hybridization (ISH) and qRT-PCR. We investigated the biological functions of LINC00460 in CRC by in vitro and in vivo experiments. We predicted the mechanism and downstream functional molecules of LINC00460 by bioinformatics analysis, and confirmed them by dual luciferase reporter gene assay, RNA immunoprecipitation (RIP), RNA pull-down, etc.ResultsLINC00460 was found to be significantly overexpressed in CRC and associated with poor prognosis. Overexpression of LINC00460 promoted CRC cell immune escape and remodeled a suppressive tumor immune microenvironment, thereby promoting CRC proliferation and metastasis. Mechanistic studies showed that LINC00460 served as a molecular sponge for miR-186-3p, and then promoted the expressions of MYC, CD47 and PD-L1 to facilitate CRC cell immune escape. We also demonstrated that MYC upregulated LINC00460 expression at the transcriptional level and formed a positive feedback loop.ConclusionsThe LINC00460/miR-186-3p/MYC feedback loop promotes CRC cell immune escape and subsequently facilitates CRC proliferation and metastasis. Our findings provide novel insight into LINC00460 as a CRC immune regulator, and provide a potential therapeutic target for CRC patients.

UKLF/PCBP2 axis governs the colorectal cancer development by transcriptionally activating SLC39A4

Colorectal cancer (CRC) is one of the most prevalent malignant tumors with limited treatment options. Therefore, there is an urgent need to investigate new therapeutic targets against CRC. Ubiquitous Kruppel-like factor (UKLF) is involved in various cancer processes, but its effect and detailed molecular mechanism in CRC are not yet fully understood. Here, this study aimed to investigate the function and mechanism of UKLF in the development of CRC. The results showed that UKLF was highly expressed in CRC tissues from clinical patients and its high expression was related to poor prognosis. UKLF promoted cell proliferation, migration and invasion, and inhibited cell apoptosis. The promotion effect of UKLF on tumor growth was further confirmed in vivo. As far as the mechanism was concerned, poly (C) binding protein 2 (PCBP2) was verified to bind to the 3′-UTR of UKLF mRNA and enhance its mRNA stability. Moreover, UKLF modulated the expression of solute carrier family 39 member 4 (SLC39A4) at the transcriptional level. Taken together, these findings elucidated the regulatory mechanism of UKLF and uncovered the importance of the PCBP2/UKLF/SLC39A4 pathway. The targeting of UKLF may be a novel direction for molecular-targeted CRC therapy.

CHL1 inhibits cell proliferation, migration and invasion by regulating the NF‑κB signaling pathway in colorectal cancer.

Cell adhesion molecule close homolog of L1 (CHL1) is implicated in tumorigenesis of various malignancies. However, its role and underlying molecular mechanisms in colorectal cancer (CRC) remain unclear. The present study aimed to evaluate the specific biological functions and mechanisms of CHL1, in order to provide a theoretical basis for the use of CHL1 as a biological target in CRC. CHL1 expression was originally determined in CRC cell lines. Subsequently, CHL1 overexpression was induced by plasmid transfection in HT29 and SW480 cells, and cell proliferation, migration and invasion were evaluated using the Cell Counting Kit-8, clone formation, organoids formation and Transwell assays. Immunofluorescence and western blotting were performed to assess the protein expression of E-cadherin or N-cadherin. Differentially expressed genes (DEGs) were further evaluated using RNA-sequencing (RNA-seq) in HT29 and SW480 cells following CHL1 overexpression and functional enrichment analysis. Western blotting was performed to validate the expression of proteins related to the nuclear factor κB (NF-κB) signaling pathway. The TNMplot online database revealed the significant downregulation of CHL1 in CRC tissues. The results indicated that exogenous CHL1 overexpression significantly inhibited the proliferative, organoid-forming, migratory and invasive abilities of HT29 and SW480 cells, and increased E-cadherin protein expression. Additionally, CHL1 overexpression reduced xenograft tumor growth in vivo. RNA-seq and functional analysis revealed that DEGs in CHL1 overexpressing cells were mainly enriched in the NF-κB signaling pathway. The expression of p-p65 and p-p65/p65 ratio were significantly reduced in HT29 and SW480 cells, following CHL1 overexpression. Additionally, the inhibitory effects of CHL1 overexpression on CRC cell proliferation, organoid formation, migration and invasion were partially counteracted following the overexpression of p65 expression. Overall, the present study demonstrates that CHL1 inhibits CRC cell growth, migration and invasion through the inactivation of the NF-κB signaling pathway.

Creatine kinase mitochondrial 2 promotes the growth and progression of colorectal cancer via enhancing Warburg effect through lactate dehydrogenase B.

Mitochondrial creatine kinase (MtCK) plays a pivotal role in cellular energy metabolism, exhibiting enhanced expression in various tumors, including colorectal cancer (CRC). Creatine kinase mitochondrial 2 (CKMT2) is a subtype of MtCK; however, its clinical significance, biological functions, and underlying molecular mechanisms in CRC remain elusive. We employed immunohistochemical staining to discern the expression of CKMT2 in CRC and adjacent nontumor tissues of patients. The correlation between CKMT2 levels and clinical pathological factors was assessed. Additionally, we evaluated the association between CKMT2 and the prognosis of CRC patients using Kaplan-Meier survival curves and Cox regression analysis. Meanwhile, quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the expression levels of CKMT2 in different CRC cell lines. Finally, we explored the biological functions and potential molecular mechanisms of CKMT2 in CRC cells through various techniques, including qRT-PCR, cell culture, cell transfection, western blot, Transwell chamber assays, flow cytometry, and co-immunoprecipitation. We found that CKMT2 was significantly overexpressed in CRC tissues compared with adjacent nontumor tissues. The expression of CKMT2 is correlated with pathological types, tumor size, distant metastasis, and survival in CRC patients. Importantly, CKMT2 emerged as an independent prognostic factor through Cox regression analysis. Experimental downregulation of CKMT2 expression in CRC cell lines inhibited the migration and promoted apoptosis of these cells. Furthermore, we identified a novel role for CKMT2 in promoting aerobic glycolysis in CRC cells through interaction with lactate dehydrogenase B (LDHB). In this study, we found the elevated expression of CKMT2 in CRC, and it was a robust prognostic indicator in CRC patients. CKMT2 regulates glucose metabolism via amplifying the Warburg effect through interaction with LDHB, which promotes the growth and progression of CRC. These insights unveil a novel regulatory mechanism by which CKMT2 influences CRC and provide promising targets for future CRC therapeutic interventions.

Dysregulation of transcripts SMAD4-209 and SMAD4-213 and their respective promoters in colon cancer cell lines.

Background: The pervasive role of alternative promoters in context-specific isoform expression and the importance of promoter choice over its level of transcriptional activity have been recently implied based on pan-cancer in silico studies. We aimed to explore this phenomenon at the cellular level on the example of a major tumor suppressor SMAD4 in search of molecular mechanisms in colorectal cancer that could be exploited for novel biomarkers or therapeutic approaches. Methods: Multi-omics technologies, in silico tools and in vitro functional assays were applied to analyze the transcripts expression and the alternative promoters' function of the SMAD4 gene in colon cell lines HCEC-1CT, HCT116, DLD-1, SW480 and SW620. Results: High expression of the transcript SMAD4-213 emerged as a hallmark of colon cancer cells, while in silico tools point to its possible additional role and potential for sponging miRNAs. Based on the observed dysregulation of SMAD4-209 and SMAD4-213 in malignant vs. non-malignant colon cells, we propose that their expression ratio might be a solid biomarker candidate for colorectal cancer detection. Conclusions: A differential pattern of the respective promoters' activity was observed that corresponds to the expression of transcripts, confirming the role of alternative promoters in context-specific isoform expression. The investigated SMAD4 promoters and transcripts harbor translational potential that should be further investigated.

Molecular mechanism of colorectal cancer and screening of molecular markers based on bioinformatics analysis.

Genomics and bioinformatics methods were used to screen genes and molecular markers correlated with colorectal cancer incidence and progression, and their biological functions were analyzed. Differentially expressed genes were obtained using the GEO2R program following colorectal cancer chip data GSE44076 retrieval from the Gene Expression Omnibus gene expression comprehensive database. An online database (David) that combines annotation, visualization, and gene discovery was utilized for investigating genes. Pathway and protein analyses were performed via resources from the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). Visual analysis of the KEGG pathway was carried out according to ClueGO and CluePedia to establish the PPI network of gene interaction between pathways; the genes with the highest connectivity were screened by the molecular complex detection analysis method as Hub genes in this study; gene expression was verified by GEPIA online analysis tool, and Kaplan-Meier survival curve was drawn for prognosis analysis. By analyzing GSE44076 microarray data, 86 genes were selected, and colorectal cancer tissues' upregulation was observed in 27 genes and downregulation in 59 ones. GO assessment revealed that the differentially expressed genes were basically correlated with retinol dehydrogenase activity, carbon dehydrogenase activity, collagen-containing extracellular matrix, anchored component of memory, and cellular hormone metabolic process. Moreover, the KEGG assessment revealed that the differential genes contained various signal pathways such as retinol metabolism, chemical carotenogenesis, and nitrogen metabolism. Through further analysis of the PPI protein network, 4 clusters were obtained, and 16 Hub genes were screened out by combining the degree of each gene. Through the analysis of each gene on the prognosis of colon cancer through the GEPIA online analysis website, it was found that the expression levels of AQP8, CXCL8, and ZG16 genes were remarkably associated with colon cancer prognosis (P < 0.05). Genomics and bioinformatics methods can effectively analyze the genes and molecular markers correlated with colorectal cancer incidence and progression, help to systematically clarify the molecular mechanism of 16 key genes in colorectal cancer development and progression, and provide a theoretically valid insight for the screening of diagnostic markers of colorectal cancer and the selection of accurate targets for drug therapy.

Oncogene SCARNA12 as a potential diagnostic biomarker for colorectal cancer

Colorectal cancer (CRC) is one of the most common malignant tumors of the digestive system, and represents a severe threat to the life and health of individuals. Increasing evidence supports the role of small nucleolar RNAs (snoRNAs) as critical regulatory gene in cancer development. Small Cajal body-specific RNAs (scaRNAs), a subtype of snoRNAs, are named for their subcellular localization within Cajal bodies. SCARNA12, which located at the intronic region of PHB2 in chromosome 12p13.31 with 270 nucleotides (nt) in length. It has been reported function as a diagnostic marker for cervical cancer. However, its biological functions and molecular mechanisms in CRC have yet to be elucidated. In this study, bioinformatics analysis revealed that SCARNA12 was highly expressed in CRC and positively correlated with poor prognosis in CRC patients. Additionally, SCARNA12 showed upregulated expression in CRC cell lines and clinical CRC tissue samples. Moreover, SCARNA12 overexpression in SW620 cells accelerated cell proliferation, suppressed the apoptosis rate, and enhanced tumorigenesis in vivo. The knockdown of SCARNA12 expression in HCT116 and HT29 cells resulted in contrasting effects. The functioning of SCARNA12 is mechanically independent of its host gene PHB2. Notably, the overexpression of SCARNA12 activated PI3K/AKT pathway in SW620 cells, and the malignancy degree of CRC cells was attenuated after treatment with MK2206 (a specific AKT inhibitor). Our findings demonstrated that SCARNA12 plays an oncogenic role in CRC progression and can be used as a potential diagnostic biomarker for CRC.

LncRNA RPLP0P2 Promotes Colorectal Cancer Proliferation and Invasion via the miR-129-5p/Zinc Finger and BTB Domain-Containing 20 Axis.

We previously reported that long non-coding RNA (lncRNA) RPLP0P2 is involved in the progression of colorectal cancer (CRC); however, its molecular mechanisms in CRC remain unclear. In this study, we observed that RPLP0P2 was upregulated in CRC tissues and cell lines. Cell viability was measured using the MTT and colony formation assays. Migration and invasion capabilities were monitored by wound healing, transwell, and immunofluorescence assays. The results showed that RPLP0P2 downregulation inhibited cell viability, migration, and invasion capabilities of CRC cells, accompanied by decreased PCNA, N-cadherin, and Vimentin, and increased E-cadherin expression. Using the DIANA online database, miR-129-5p was identified as a downstream target of RPLP0P2. In fact, RPLP0P2 colocalized with miR-129-5p, acting as a miR-129-5p sponge. MiR-129-5p-inhibition almost abrogated the anti-tumor effects induced by RPLP0P2 inhibition in CRC cells. Zinc finger and BTB domain-containing 20 (ZBTB20) was identified as a potential downstream target of miR-129-5p in CRC cells. ZBTB20 overexpression prevented miR-129-5p mimic-mediated anti-tumor effects in CRC cells. A tumor xenograft assay was performed to monitor the role of RPLP0P2 in tumor growth. Of note, in tumor-bearing mice, RPLP0P2-silencing inhibited tumor growth, followed by increased miR-129-5p and decreased ZBTB20 expression. Our results suggest that lncRNA RPLP0P2 functions as an oncogene that promotes CRC cell proliferation and invasion via regulating the miR-129-5p/ZBTB20 axis, thus, it may serve as a candidate target for CRC interventional therapies.

TSPYL5 inhibits the tumorigenesis of colorectal cancer cells in vivo by triggering DNA damage.

Testis-specific protein Y-encoded-like 5 (TSPYL5) suppresses several cancers in vivo, including colorectal cancer (CRC); however, its mechanism and role in CRC cell tumorigenesis in vivo remain unknown. To elucidate the molecular mechanisms of colorectal cancer and find new therapeutic targets to improve CRC patient outcomes. Male mice (4 weeks old, 16-22 g) were housed in sterile cages in a temperature-controlled room (20-25°C) with a 12 h light/dark cycle and ad libitum food and water. TSPYL5 overexpressing or non-overexpressing HCT116 cells were used to create a nude mouse tumor model. Tumor tissue was evaluated histologically after hematoxylin and eosin (H and E) staining. TUNEL staining assessed tumor cell apoptosis. Ki67 expression in excised tumor tissue was measured by immunohistochemistry. Western blotting examined double-stranded break (DBS)-associated protein expression in vivo. IBM SPSS Statistics for Windows, Version 21.0 was used for all analyses (IBM Corp., Armonk, NY, USA). At least three independent experiments yield a mean value ± standard deviation. Unpaired Student's t-tests compared groups. One-way analysis of variance and Dunnett's test were used to compare groups with a P value < 0.5. TSPYL5 overexpression inhibited CRC cell tumorigenicity and damaged tumor cells in vivo. TSPYL5 overexpression also significantly increased Bax and p-H2AX (early double-stranded break indicators) and decreased Ki67, Bcl-2, and peroxisome proliferator-activated receptor expression. Collectively, TSPYL5 overexpression inhibited the tumorigenicity of CRC cells in vivo by inducing DNA damage.

TRIM55 inhibits colorectal cancer development via enhancing protein degradation of c-Myc.

Colorectal cancer (CRC) is one of the most common and lethal malignancies which including colon and rectum cancer. Tripartite motif containing 55 (TRIM55) is an E3 ubiquitin ligase belonging to the TRIM family. Although the aberrant TRIM55 expression has been implicated in several tumors, its functional role, and molecular mechanisms in CRC remain unknown. Immunohistochemical studies, qRT-PCR, and Western blot were performed to analyze the expression of TRIM55 in CRC patients and cell lines. TRIM55 expression and its relevance to clinical traits and prognosis were further explored in the TCGA database, and in our 87 clinical samples. Subsequently, we performed a series of functional assays to explore the effect of TRIM55 on CRC progression. Finally, the molecular mechanism of TRIM55 was investigated by immunoprecipitation and ubiquitination analyses. Here, we demonstrated that TRIM55 was markedly downregulated in CRC cell lines and tumors from CRC patients. Moreover, overexpression of TRIM55 could suppress CRC cell growth in vitro and inhibit CRC xenograft tumor development in vivo. Additionally, TRIM55 overexpression dampened CRC cell migration and invasion. Further bioinformatics analysis indicated that TRIM55 suppressed cyclin D1 and c-Myc expression. Mechanistically, co-immunoprecipitation assay revealed that TRIM55 directly interacted with c-Myc and down-regulated its protein expression level via protein ubiquitination. Intriguingly, c-Myc overexpression partially antagonized the function of TRIM55 overexpression. Taken together, our findings suggest that TRIM55 inhibits CRC tumor development via, at least in part, enhancing protein degradation of c-Myc. Targeting TRIM55 could provide a new therapeutic approach for CRC patients.

Comprehensive analysis of RNA-binding protein SRSF2-dependent alternative splicing signature in malignant proliferation of colorectal carcinoma

Aberrant expression of serine/arginine-rich splicing factor 2 (SRSF2) can lead to tumorigenesis, but its molecular mechanism in colorectal cancer is currently unknown. Herein, we found SRSF2 to be highly expressed in human colorectal cancer (CRC) samples compared with normal tissues. Both invitro and invivo, SRSF2 significantly accelerated the proliferation of colon cancer cells. Using RNA-seq, we screened and identified 33 alternative splicing events regulated by SRSF2. Knockdown of SLMAP-L or CETN3-S splice isoform could suppress the growth of colon cancer cells, predicting their role in malignant proliferation of colon cancer cells. Mechanistically, the invivo crosslinking immunoprecipitation assay demonstrated the direct binding of the RNA recognition motif of SRSF2 protein to SLMAP and CETN3 pre-mRNAs. SRSF2 activated the inclusion of SLMAP alternative exon 24 by binding to constitutive exon 25, while SRSF2 facilitated the exclusion of CETN3 alternative exon 5 by binding to neighboring exon 6. Knockdown of SRSF2, its splicing targets SLMAP-L, or CETN3-S caused colon cancer cells to arrest in G1 phase of the cell cycle. Rescue of SLMAP-L or CETN3-S splice isoform in SRSF2 knockdown colon cancer cells could effectively reverse the inhibition of cell proliferation by SRSF2 knockdown through mediating cell cycle progression. Importantly, the percentage of SLMAP exon 24 inclusion increased and CETN3 exon 5 inclusion decreased in CRC samples compared to paired normal samples. Collectively, our findings identify that SRSF2 dysregulates colorectal carcinoma proliferation at the molecular level of splicing regulation and reveal potential splicing targets in CRC patients.

Hsa_circ_0001535 Regulates Colorectal Cancer Progression via the miR-433-3p/RBPJ Axis.

A large number of studies have shown that circular RNAs (circRNAs) are of great significance in the occurrence and development of colorectal cancer (CRC). The purpose of this study was to explore the mechanism of circ_0001535 in CRC. The expressions of circ_0001535, miR-433-3p and recombination signal-binding protein Jκ (RBPJ) mRNA and protein in CRC tissues and cells were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. The effect of circ_0001535 on cell proliferation was detected using the Cell Counting Kit-8 (CCK-8) assay, colony formation assay and 5-ethynyl-2'-deoxyuridine (EdU) assay. The effects of circ_0001535 on migration, invasion, angiogenesis and apoptosis were investigated by wound healing assay, transwell assay, tube formation assay and flow cytometry, respectively. The interactions between miR-433-3p and circ_0001535 or RBPJ were studied using dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Xenograft tumor assay was performed to verify the role of circ_0001535 in tumor growth in vivo. The results showed that circ_0001535 and RBPJ mRNA expression levels were up-regulated and miR-433-3p was down-regulated in CRC tissues and cells. Circ_0001535 knockdown inhibited cell proliferation, migration, invasion, angiogenesis as well as promoted apoptosis in CRC cells. After analysis, it was found that circ_0001535 acted as a competing endogenous RNA (ceRNA) to inhibit miR-433-3p and then up-regulate RBPJ in CRC cells. In addition, in vivo experiment had shown that circ_0001535 knockdown inhibited tumor growth by up-regulating miR-433-3p and inhibiting RBPJ expression. The circ_0001535/miR-433-3p/ RBPJ axis plays a catalytic role in the progression of CRC, which may provide new insights into the molecular mechanism of CRC.

Analysis of LINC01314 and miR-96 Expression in Colorectal Cancer Patients via Tissue Microarray-Based Fluorescence In Situ Hybridization.

Methods A tissue microarray (TMA) containing 76 individual colorectal tumor samples and 28 adjacent normal samples was constructed, and the expression levels of LINC01314 and miR-96 were detected by fluorescence in situ hybridization. Results The expression levels of both LINC01314 and miR-96 were upregulated in CRC tissues and were associated with vascular metastasis (p < 0.05). A significantly positive correlation was observed between LINC01314 and miR-96 expression in tumor tissues (p < 0.001, r = 0.870). Dominant expression of LINC01314 was a risk factor for both blood vessel invasion (p < 0.05) and poor 5-year survival (p = 0.001, hazard ratio = 4.144). The Kaplan–Meier analysis indicated that patients with LINC01314-dominant expression exhibited worse 5-year survival rates than those with miR-96-dominant expression (p < 0.05). Conclusion The expression patterns of both LINC01314 and miR-96 may be diagnostic of, and prognostic for, CRC. These findings will facilitate further exploration of the molecular mechanism of lncRNAs in CRC.

BPTF inhibition antagonizes colorectal cancer progression by transcriptionally inactivating Cdc25A

As the largest subunit of the nuclear remodeling factor complex, Bromodomain PHD Finger Transcription Factor (BPTF) has been reported to be involved in tumorigenesis and development in several cancers. However, to date, its functions and related molecular mechanisms in colorectal cancer (CRC) are still poorly defined and deserve to be revealed. In this study, we uncovered that, under the expression regulation of c-Myc, BPTF promoted CRC progression by targeting Cdc25A. BPTF was found to be highly expressed in CRC and promoted the proliferation and metastasis of CRC cells through BPTF specific siRNAs, shRNAs or inhibitors. Based on RNA-seq, combined with DNA-pulldown, ChIP and luciferase reporter assay, we proved that, by binding to −178/+107 region within Cdc25A promoter, BPTF transcriptionally activated Cdc25A, thus accelerating the cell cycle process of CRC cells. Meanwhile, BPTF itself was found to be transcriptionally regulated by c-Myc. Moreover, BPTF knockdown or inactivation was verified to sensitize CRC cells to chemotherapeutics, 5-Fluorouracil (5FU) and Oxaliplatin (Oxa), c-Myc inhibitor and cell cycle inhibitor not just at the cellular level in vitro, but in subcutaneous xenografts or AOM/DSS-induced in situ models of CRC in mice, while Cdc25A overexpression partially reversed BPTF silencing-caused tumor growth inhibition. Clinically, BPTF, c-Myc and Cdc25A were highly expressed in CRC tissues simultaneously, the expression of any two of the three was positively correlated, and their expressions were highly relevant to tumor differentiation, TNM staging and poor prognosis of CRC patients. Thus, our study indicated that the targeted inhibition of BPTF alone, or together with chemotherapy and/or cell cycle-targeted therapy, might act as a promising new strategy for CRC treatment, while c-Myc/BPTF/Cdc25A signaling axis is expected to be developed as an associated set of candidate biomarkers for CRC diagnosis and prognosis prediction.

MiR-887-3p Inhibits the Progression of Colorectal Cancer via Downregulating DNMT1 Expression and Regulating P53 Expression.

Colorectal cancer (CRC) is the third most diagnosed cancer worldwide and the second leading cause of cancer-related deaths. Many researchers have reported that abnormal microRNAs (miRs) were expressed in CRC and participated in the occurrence and progression of CRC. However, there are few reports of miR-887-3p regulating CRC development. In the current study, we investigated the abnormal expression of miR-887-3p and also demonstrated its regulatory role and detailed molecular mechanism in CRC. Initially, miRNA expression data were obtained from TCGA-COAD that consisted of 453 CRC samples and 8 normal tissue samples. These were downloaded and analyzed to compare the expression level of miR-887-3p in CRC tissues to that in normal tissues. Moreover, 32 pairs of surgically resected CRC tumors and para-cancer tissues from our hospital were collected. Quantitative real-time PCR (qRT-PCR) was performed to detect miR-887-3p expression levels in CRC tissues, para-cancer tissues, several CRC cell lines, and an intestinal epithelial cell line. Following miR-887-3p mimic transfection in colon cancer SW480 cell line, the regulatory roles of miR-887-3p on cell proliferation, apoptosis, invasion, migration, and epithelial-mesenchymal transition (EMT) were detected through CCK-8, flow cytometry, transwell assay, and Western blot. After potential targeting protein was predicted by bioinformatic websites, the luciferase reporter assay and Western blot were used to confirm the target of miR-887-3p. The targeting protein expressions were detected by Western blot and qRT-PCR. The relationship between miR-887-3p level and the effect of miR-887-3p on P53 expression was evaluated by Western blot and qRT-PCR. The effects of miR-887-3p on CRC cell growth in vivo by xenograft tumor experiments were investigated, and Ki-67 in tumor tissue was determined by immunohistochemistry. Results. The COAD data demonstrated that the expression levels of miR-887-3p in CRC clinical sample tissues and cell line cultures were remarkably lower than para-cancer normal tissues and NCM460 cells (normal colonic epithelial cell line). Functional experiments demonstrated that overexpression of miR-887-3p in SW480 cells significantly reduced proliferation, migration, invasion, and EMT, and promoted cancer cell apoptosis. Additionally, Western blot, qRT-PCR, and luciferase reporter assays confirmed that DNMT1 was a downstream target of miR-887-3p. Moreover, the blocking of DNMT1 by miR-887-3p mimics also promoted P53 expression. Finally, overexpression of DNMT1 in SW480 cells could partially reverse the regulatory effect of miR-887-3p mimics on CRC cell development. From in vivo experiments, overexpression of miR-887-3p could inhibit tumor growth in CRC xenograft mice and reduce the Ki-67 level. Conclusion. The microRNA miR-887-3p is a potential biomarker of CRC. It inhibited CRC cell proliferation, invasion, and EMT, and promoted cell apoptosis through targeting and downregulating DNMT1 and promoting P53 expression. Therefore, miR-887-3p may be a good biomarker and therapeutic target for CRC treatment.

BCAP31 is involved in modulating colorectal cancer cell proliferation via the Emerin/β-catenin axis

Understanding the mechanisms of colorectal cancer (CRC) progression is critical for developing innovative treatment strategies. As an endoplasmic reticulum-located protein, B cell receptor-associated protein 31 (BCAP31) has been identified to be highly expressed in multiple cancers. However, its function and molecular mechanism in CRC remain not fully understood. In the present study, BCAP31 expression and its correlation with the clinical stage were analyzed based on TCGA database. We demonstrated that loss of BCAP31 suppressed CRC cell proliferation in vitro and tumor growth in vivo. Mechanistically, we demonstrated that Emerin was an interaction partner and downstream molecule of BCAP31. Knockdown of BCAP31 promoted the nuclear envelope localization of Emerin, leading to a reduction of β-catenin accumulation in the nucleus, which resulted in downregulation of Wnt/β-catenin downstream target genes, including c-Myc, cyclin D1, Survivin, and Mcl-1. Moreover, downregulation of Emerin partially restored the BCAP31 depletion-mediated β-catenin protein level and tumor suppressive effects in CRC cells.Our data highlights the pivotal role of BCAP31 depletion in inhibiting cell proliferation in CRC cells, and mechanistically via Emerin/β-catenin signaling, which may serve as a promising target for CRC treatment.

ADH1C inhibits progression of colorectal cancer through the ADH1C/PHGDH /PSAT1/serine metabolic pathway.

Colorectal cancer (CRC) is the third most common cancer in men and the second most common cancer in women worldwide. CRC is the second leading cause of cancer-related deaths. Although some progress in the treatment of CRC has been achieved, the molecular mechanism of CRC is still unclear. In this study, alcohol dehydrogenase 1C(ADH1C) was first identified as a target gene closely associated with the development of CRC by the comprehensive application of transcriptomics, proteomics, metabonomics and insilico analysis. The ADH1C mRNA and protein expression in CRC cell lines and tumor tissues was lower than that in normal intestinal epithelial cell lines and healthy tissues. Overexpression of ADH1C inhibited the growth, migration, invasion and colony formation of CRC cell lines and prevented the growth of xenograft tumors in nude mice. The inhibitory effects of ADH1C on CRC cells in vitro were exerted by reducing the expression of PHGDH/PSAT1 and the serine level. This inhibition could be partially reversed by adding serine to the culture medium. These results showed that ADH1C is a potential drug target in CRC.

MicroRNAs and drug resistance in colorectal cancer with special focus on 5-fluorouracil.

Colorectal cancer is globally one of the most common cancers in all age groups. The current chemotherapy combinations for colorectal cancer treatment include 5-fluorouracil-based regimens; however, drug resistance remains one of the main reasons for chemotherapy failure and disease recurrence. Many studies have determined colorectal cancer chemoresistance mechanisms such as drug efflux, cell cycle arrest, DNA damage repair, apoptosis, autophagy, vital enzymes, epigenetic, epithelial-mesenchymal transition, stem cells, and immune system suppression. Several microRNAs affect drug resistance by regulating the drug resistance-related target genes in colorectal cancer. These drug resistance-related miRNAs may be used as promising biomarkers for predicting drug response or as potential therapeutic targets for treating patients with colorectal cancer. This work reviews and discuss the role of selected microRNAs in 5-fluorouracil resistance and their molecular mechanisms in colorectal cancer.

Identification of target genes and prognostic evaluation for colorectal cancer using integrated bioinformatics analysis

The underlying molecular mechanisms of colorectal cancer (CRC) has attracted great attention from the scholarly community. The aim of our study is to identify pivotal genes related to the pathogenesis and prognosis of CRC. We integrated five microarray datasets from Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) were analyzed with the limma package. DAVID and OmicShare tools were used for Gene Ontology (GO) and KEGG enrichment analysis. The protein–protein interaction (PPI) network of DEGs was constructed. The prognostic analysis of hub genes was performed through Kaplan Meier-plotter. Finally, potential drugs were predicted in the CMap database. Through five microarray datasets, a total of 90 DEGs were detected including 54 up-regulated and 36 down-regulated genes. Biological process analysis showed DEGs were mainly enriched in positive regulation of neutrophil chemotaxis, chemokine-mediated signaling pathway, and bicarbonate transport. Signaling pathway analysis indicated that DEGs played a vital in proximal tubule bicarbonate reclamation, cell cycle and progesterone-mediated oocyte maturation. The GEPIA database confirmed that overexpression levels of hub genes were significantly associated with better survival of patients. Finally, the 20 most significant small molecules were obtained based on the CMap database. Our study has identified novel candidate biomarkers, pathways, and kinases associated with CRC prognosis.