Circular RNAs (circRNAs) are a class of stable non-coding RNAs that have emerged as key regulators in human diseases including cancer. This study investigates the role of circRNA_0102913 (circ_0102913) in malignant behavior of colorectal cancer (CRC) cells and the underpinning mechanisms. By analyzing CRC-related GSE197991, GSE159669, and GSE223001 datasets, we obtained circ_0102913 as an aberrantly upregulated circRNA in CRC. Increased circ_0102913 expression was detected in CRC tissues and cells. By querying multiple bioinformatics systems (circBank, Circular RNA Interactome, TargetScan, miRDIP, miRwalk, and miRDB), we identified microRNA-571 (miR-571) as a target of circ_0102913 and Rac family small GTPase 2 (RAC2) mRNA as a target of miR-571. Biotinylated-RNA pull-down and/or luciferase assays showed that circ_0102913 bound to miR-571 to restore the expression of RAC2 mRNA. Circ_0102913 silencing or miR-571 overexpression repressed proliferation, migration and invasion, and in vivo tumorigenesis abilities of CRC cells. However, the malignant properties of cells were restored by RAC2 overexpression. The increased circ_0102913 expression in CRC cells was attributed to increased 5-methylcytosine (m5C) modification levels. Silencing of NOP2/Sun RNA methyltransferase 5 reduced the m5C level and therefore reduced stability and expression of circ_0102913 expression in CRC cells. In conclusion, this study demonstrates that m5C-mediated upregulation of circ_0102913 augments malignant properties of CRC cells through a miR-571/RAC2 axis.

Circular RNA (circRNAs) have been found to play major roles in the progression of colorectal cancer (CRC). However, the functions of circ_0008345 (transcribed by PTK2) in regulating CRC development remain undefined. In this study, we aimed to explore the roles and underlying mechanisms of circ_0008345 in CRC. RNase R-treated total cellular RNA was used to verify the circular structure of circ_0008345, and a subcellular fractionation assay was performed to detect the subcellular localization of circ_0008345. RNA pull-down and dual-luciferase assays were used to verify the binding relation between microRNA (miR)-182-5p and circ_0008345 and/or CYP1A2. Colony formation assay, EdU, and Transwell assays were performed to detect the biological behavior of CRC cells in vitro, and CRC cells were injected into mice to observe the tumor formation. m6A immunoprecipitation was used to detect the m6A modification of circ_0008345 in CRC cells. Circ_0008345, upregulated in CRC tissues and cells, was mainly present in the cytoplasm. Circ_0008345 bound to miR-182-5p, and miR-182-5p targeted CYP1A2, an oncogene in CRC. The colony formation, mobility, EdU-positive cell rate in vitro, and tumor growth in mice were inhibited after the knockdown of circ_0008345. However, the suppressing effects of sh-circ_0008345 on CRC and CYP1A2 expression were significantly reversed after further knockdown of miR-182-5p. METTL3 was the m6A modifier mediating circ_0008345 expression, and the suppression of METTL3 reduced the expression of circ_0008345. METTL3-dependent m6A methylation upregulated circ_0008345, which blocked the inhibitory effect of miR-182-5p on CYP1A2, thereby exacerbating the malignant phenotype of CRC cells.

Background: REEP4 is involved in the regulation of the biological process of mitosis. Lower grade glioma (LGG), as a malignant tumor, is accompanied by abnormalities in mitosis, but there have been no reports of REEP4 so far. Methods: We collected transcriptome data, DNA methylation data and the clinical characteristics of thousands of patients with LGG. Various big data analysis methods and molecular biology experiments were employed to reveal the impact of REEP4 on the pathological process of LGG. Results: It was found that the expression of REEP4 was significantly elevated and negatively regulated by its methylation site. Therefore, both the high expression of REEP4 and low methylation state of cg16311504 showed that the patients are correlated with lower patient survival rate. In addition, high REEP4 expression participates in the regulation of various cancer-related cellular signaling pathways, such as the cell cycle, MAPK signaling pathway, NOD-like receptor signaling pathway, etc. More importantly, the level of immune cell infiltration significantly increased in the high expression group of REEP4 in the LGG tumor microenvironment and REEP4 has a high positive correlation with PD-L1 and other immune checkpoints. Conclusions: In brief, this study is the first to introduce REEP4 in malignant tumors, which can be used as an independent risk factor that participates in the malignant process of LGG. More importantly, REEP4 has the potential to become a new star in the field of anti-tumor treatment.

Objective:To analyze the clinical effect of modified Maziren decoction in treating constipation after surgery for anal fissure and hemorrhoid fistula.Methods:One hundred and ten patients with constipation after surgery for anal fissure and hemorrhoid fistula who were treated in Zhengzhou Central Hospital Affiliated to Zhengzhou University from January 2021 to December 2022 were selected. According to the random number table method, the selected patients were divided into control group and study group, with 55 cases in each group. The control group received conventional western medicine treatment (phenolphthalein tablets), while the study group received modified Maziren decoction treatment. The total effective rate of treatment of the two groups were compared. The changes in the clinical constipation scale (CCS) score, Wexner continence grading scale (Wexner) score, and traditional Chinese medicine syndrome score of constipation of the two groups were compared before and after treatment. The occurrence of adverse reactions of the two groups were compared.Results:There was no significant difference in the total effective rate between the study group (96.36%, 53/55) and the control group (90.91%, 50/55), P>0.05. Before treatment, there was no statistically significant difference in CCS score and Wexner score between the two groups ( P>0.05); after treatment, the CCS score and Wexner score of the two groups were lower than those before treatment (all P<0.05), but there was no statistically significant difference in the above scores between the two groups ( P>0.05). Before treatment, there was no statistically significant difference in the traditional Chinese medicine symptom score of constipation between the two groups ( P>0.05); after treatment, the two groups had lower score of abdominal distension, bowel ringing and obstructed defecation, compared with preoperative scores (all P<0.05); but there was no significant difference in the above scores between the two groups ( P>0.05). The incidence of adverse reactions in the study group (1.82%, 1/55) was lower than that in the control group (12.73%, 7/55), P<0.05. Conclusions:Modified Maziren decoction has an ideal clinical effect and fewer adverse reactions in the treatment of constipation after surgery for anal fissure and hemorrhoid fistula.

Abstract As important regulatory molecules, LncRNAs play an important role in regulating the pathological progress of malignant tumor. However, the effect of LncRNA-HOXD-AS2 on the prognosis of colorectal cancer and its regulatory mechanism has not been confirmed. Therefore, this study obtained the transcriptome data and clinicopathological characteristics of colorectal cancer from TCGA database to predict the impact of HOXD-AS2 on the prognosis of patients and its regulatory mechanism. It was found that the high expression of HOXD-AS2 had a positive relationship with the expression of pathological T and tumor stages and can significantly reduce the overall survival of patients and have diagnostic value for prognosis. Subsequent, GSEA prediction found that HOXD-AS2 could promote the activation of TGF-β signaling pathway. MTT assay and Ki67 staining assay confirmed that HOXD-AS2 knockdown could significantly inhibit the proliferation ability of the SW480 and SW620 cells of colorectal cancer. Transwell assay and wound healing assay demonstrated that knockdown of HOXD-AS2 could significantly inhibit the invasion and migration of SW480 and SW620 cells. Finally, Western blotting showed that the knockdown of HOXD-AS2 could significantly reduce the expression level of key proteins of TGF-β signaling pathway. Collectively, this study revealed the regulatory effect of HOXD-AS2 on the pathological mechanism of colorectal cancer for the first time, and broadened the molecular function of HOXD-AS2. The increased expression of HOXD-AS2 in colorectal cancer can be used as a biological target for the biological treatment of colorectal cancer.

Background This study attempted to verify the potential of KCNJ14 as a biomarker in colorectal cancer (CRC). Methods Data on transcriptomics and DNA methylation and the clinical information of CRC patients were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus databases. Biological information analysis methods were conducted to determine the role of KCNJ14 in the prognosis, diagnosis, immune cell infiltration, and regulation mechanism of CRC patients. The effect of KCNJ14 on the proliferation and migration of HCT116 and SW480 CRC cell lines was verified by in vitro experiments (MTT, colony-forming, wound healing, and transwell assays). Western blotting was performed to detect the effect of KCNJ14 on the levels of mTOR signalling pathway-related proteins. Results KCNJ14 expression was remarkably increased in CRC tissues and cell lines, which reduced the overall survival time of patients. KCNJ14 mRNA was negatively regulated by its methylation site cg17660703, which can also endanger the prognosis of patients with CRC. Functional enrichment analysis suggested that KCNJ14 is involved in the mTOR, NOD-like receptor, and VEGF signalling pathways. KCNJ14 expression was positively correlated with the number of CD4 + T cells and negatively correlated with that of CD8 + T cells in the immune microenvironment. KCNJ14 knockdown significantly reduced not only the proliferation and migration of CRC cell lines but also the levels of mTOR signalling pathway-related proteins. Conclusions This study not only increases the molecular understanding of KCNJ14 but also provides a potentially valuable biological target for the treatment of colorectal cancer.

N 6 -methyladenosine (m 6 A), the most abundant modification in eukaryotic cells, regulates RNA transcription, processing, splicing, degradation, and translation. Circular RNA (circRNA) is a class of covalently closed RNA molecules characterized by universality, diversity, stability and conservatism of evolution. Accumulating evidence shows that both m 6 A modification and circRNAs participate in the pathogenesis of multiple diseases, such as cancers, neurological diseases, autoimmune diseases, and infertility. Recently, m 6 A modification has been identified for its enrichment and vital biological functions in regulating circRNAs. In this review, we summarize the role of m 6 A modification in the regulation and function of circRNAs. Moreover, we discuss the potential applications and possible future directions in the field.

N 6 -methyladenosine (m 6 A), the most abundant modification in eukaryotic cells, regulates RNA transcription, processing, splicing, degradation, and translation. Circular RNA (circRNA) is a class of covalently closed RNA molecules characterized by universality, diversity, stability and conservatism of evolution. Accumulating evidence shows that both m 6 A modification and circRNAs participate in the pathogenesis of multiple diseases, such as cancers, neurological diseases, autoimmune diseases, and infertility. Recently, m 6 A modification has been identified for its enrichment and vital biological functions in regulating circRNAs. In this review, we summarize the role of m 6 A modification in the regulation and function of circRNAs. Moreover, we discuss the potential applications and possible future directions in the field.