miR-219a-1 inhibits colon cancer cells proliferation and invasion by targeting MEMO1

MiR-485-3p/MiR-543/MiR-337-3p is Required for the Oncogenic Potential of the Hsa_circ_0007385-MEMO1 Axis in Colorectal Cancer

Circular RNAs (circRNAs) play regulatory roles in the biological processes of multiple tumors, colorectal cancer (CRC) included. Our previous study probed the impact of circ_0007385 on CRC cell malignant behaviors, while the underlying mechanism remains obscure. In this work, the potential mechanism of hsa_circ_0007385 in CRC was probed. Functional experiments were implemented for probing the function of hsa_circ_0007385 in CRC. Further analysis revealed the relation between hsa_circ_0007385 and miRNAs. A xenograft mouse model was implemented for probing the influence of hsa_circ_0007385 on CRC growth and metastasis in vivo. Hsa_circ_0007385 was up-regulated in CRC. Hsa_circ_0007385 positively regulated its host gene mediator of cell motility 1 (MEMO1). Hsa_circ_0007385 silencing inhibited CRC progression. Hsa_circ_0007385 and MEMO1 bond to miR-485-3p/miR-543/miR-337-3p, and these three miRNAs were lowly expressed in CRC, and negatively modulated by hsa_circ_0007385. Hsa_circ_0007385 functioned as an oncogene in CRC in a miR-485-3p/miR-543/miR-337-3p- or MEMO1-dependent manner. Hsa_circ_0007385 promoted CRC progression via modulating miR-485-3p/miR-543/miR-337-3p/MEMO1 axis. Thus, circ-MEMO1 might be a promising therapeutic target for CRC.

Examination of the effects of microRNA-145-5p and phosphoserine aminotransferase 1 in colon cancer

Previous studies manifested that microRNA-145-5p is pivotal in the development of various cancers. Nevertheless, the potential function of microRNA-145-5p in colorectal cancer remains unclear. This study attempted to investigate the potential role and possible mechanism of microRNA-145-5p in colon cancer. MicroRNA-145-5p and phosphoserine aminotransferase 1 (PSAT1) levels in colon cancer cells were assayed via quantitative reverse transcription polymerase chain reaction (qRT-PCR). Cell proliferation and cell cycle status were assessed using Cell Counting Kit-8, colony formation, and flow cytometry. The target binding relationship of microRNA-145-5p and PSAT1 was identified using bioinformatics analysis and dual-luciferase reporter gene assay. The result of qRT-PCR disclosed that microRNA-145-5p was markedly down-regulated and PSAT1 level was up-regulated in colon cancer cell lines. Besides, enforced microRNA-145-5p level repressed proliferation of colon cancer cells, and cells were arrested in G0-G1 phase. Bioinformatics analysis and dual-luciferase reporter genes confirmed that PSAT1 was a downstream target of microRNA-145-5p. Enforced PSAT1 level remarkably modulated cell cycle and fostered cell proliferation. Furthermore, rescue experiments displayed that microRNA-145-5p restrained cell cycle progression and cell proliferation and forced PSAT1 level could partially reverse this process. Taken together, our findings demonstrated that microRNA-145-5p repressed colon cancer cell cycle progression and cell proliferation via targeting PSAT1. Our findings identified microRNA-145-5p as an essential tumor repressor gene in colon cancer and may provide a novel biomarker for colon cancer.

LncRNA cancer susceptibility 20 regulates the metastasis of human gastric cancer cells via the miR-143-5p/MEMO1 molecular axis

BACKGROUND

Gastric cancer (GC) is considered as one of the most widespread malignancies. Emerging evidence has shown that lncRNAs can function as important oncogenes or tumor suppressors during GC progression.

AIM

To investigate the effect and mechanism of lncRNA cancer susceptibility 20 (CASC20) in the proliferation and metastasis of GC cells.

METHODS

Data mining and clinical samples were used to evaluate the expression of CASC20 in GC and adjacent tissues. CASC20 was down-regulated in GC cells by short-interfering RNA. Cell proliferation was evaluated by CCK-8 assay, and cell migration and invasion were detected by wound healing and Transwell assays. The expressions of proteins related to epithelial-mesenchymal transition were detected by western blot assay.

RESULTS

The expression of CASC20 was increased in GC tumor tissues and various GC cell lines. High CASC20 expression was correlated with a high risk of lymphatic metastasis and poor prognosis in GC patients. In vitro assays showed that silencing CASC20 reduced cell proliferation, migration, and invasion in GC cells. Mechanistic studies revealed that CASC20 exhibits oncogenic functions by regulating MEMO1 expression through competitive endogenous binding to miR-143-5p, leading to induction of epithelial-mesenchymal transition.

CONCLUSION

Our findings indicate that CASC20 serves as a tumor promoter by regulating metastasis in GC via the miR-143-5p/MEMO1 axis. CASC20 may be a potential therapeutic target for GC.

Genetic Polymorphisms in microRNA Genes Targeting PI3K/Akt Signal Pathway Modulate Cervical Cancer Susceptibility in a Chinese Population

Polymorphisms in microRNA (miRNA) genes could influence the expression of miRNAs that regulate the PI3K/Akt signalling pathway and play crucial roles in cancer susceptibility. To investigate the association of single nucleotide polymorphisms (SNPs) in miRNA genes of PI3K/Akt with cervical intraepithelial neoplasia (CIN) and cervical cancer (CC), nine SNPs located in miRNA genes were selected for genotyping, and the association of these SNPs with CIN and CC risk was evaluated. A total of 1,402 participants were enrolled in the current study, including 698 healthy individuals in the control group, 431 patients with CC, and 273 patients with CIN. Nine SNPs in miRNA genes (rs107822 in miR-219a, rs10877887 in let-7i, rs2292832 in miR-149, rs353293 in miR-143, rs3746444 in miR-499, rs3803808 in miR-132, rs4078756 in miR-10b, rs629367 in let-7a, and rs7372209 in miR-26a) were genotyped using MassArray, and the association of these SNPs with CIN and CC were analysed. The results showed that the frequencies of rs107822 in miR-219a and rs2292832 in miR-149 were significantly different between the control and CC groups (p < 0.005). The C allele of rs107822 in miR-219a was associated with an increased risk of CC (OR = 1.29, 95%CI:1.09–1.54) whereas the C allele of rs2292832 in miR-149 was associated with a decreased risk of CC (OR = 0.77, 95%CI:0.64–0.92). The results of inheritance model analysis showed that the best-fit inheritance models for rs107822 and rs2292832 were log-additive. The 2CC + CT genotype of rs107822 could be a risk factor for CC when compared with the TT genotype (OR = 1.28, 95%CI:1.08–1.51). The 2CC + CT genotype of rs2292832 could be a protective factor against CC when compared with the TT genotype (OR = 0.76, 95%CI:0.64–0.92). However, no association of these SNPs with CIN was found in the current study. Our results suggest that rs107822 in the promoter region of miR-219a and rs2292832 in pre-miR-149 region are associated with the risk of CC.

MiR-613 inhibits the proliferation, migration, and invasion of papillary thyroid carcinoma cells by directly targeting TAGLN2

Background

Papillary thyroid carcinoma (PTC), with a rapidly increasing incidence, is the most prevalent malignant cancer of the thyroid. However, its pathogenesis is unclear and its specific clinical indicators have not yet been identified. There is increasing evidence that microRNAs (miRNAs) play important roles in tumor occurrence and progression. Specifically, miR-613 participates in the regulation of tumor development in various cancers; however, its effects and mechanisms of action in PTC are still unclear. Therefore, in this study, we investigated the expression and function of miR-613 in PTC.

Methods

qRT-PCR was used to determine miR-613 expression in 107 pairs of PTC and adjacent-normal tissues as well as in PTC cell lines and to detect TAGLN2 mRNA expression in PTC tissues and adjacent normal tissues. Western blot analysis was performed to identify TAGLN2 and epithelial–mesenchymal transition (EMT) biomarkers. The effects of miR-613 on PTC progression were evaluated by performing MTS, wound-healing, and Transwell assays in vitro. Luciferase reporter assays were also performed to validate the target of miR-613.

Results

In PTC, miR-613 was significantly downregulated and its low expression level was associated with cervical lymph node metastasis. However, its overexpression significantly suppressed PTC cell proliferation, migration, and invasion and inhibited EMT. TAGLN2 was identified as a target of miR-613, which also significantly inhibited the expression of TAGLN2. Further, the restoration of TAGLN2 expression attenuated the inhibitory effects of miR-613 on PTC cell proliferation and metastasis.

Conclusion

Our findings demonstrated that miR-613 can suppress the progression of PTC cells by targeting TAGLN2, indicating that miR-613 plays the role of a tumor suppressor in PTC. Overall, these results suggest that the upregulation of miR-613 is a promising therapeutic strategy for PTC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02083-8.

Expression of miR-92a in colon cancer tissues and its correlation with clinicopathologic features and prognosis

OBJECTIVE

This study analyzed the expression of miR-92a in colon tumor tissues and its correlation with disease clinicopathologic features and prognosis.

METHODS

83 cases of colorectal cancer tissues and paracancerous normal tissues acquired from colon cancer resection surgery during January 2015-January 2017 were collected. We detected the expression of miR-92a in cancer tissues and paracancerous tissues by qRT-PCR, and analyzed the correlation between the relative expression of miR-92 in colon cancer tissues and clinicopathologic characteristics, progression-free survival (PFS), and overall survival (OS) of the patients accordingly.

RESULTS

The relative expression level of miR-92a in colon cancer tissues was higher than of paracancerous tissues (P<0.05). Relative expression of miR-92a in cancer was correlated with the degree of differentiation, TNM stage, and lymph node metastasis (P<0.05), while uncorrelated with gender, age, tumor diameter, or invasion depth (P>0.05). Patients with low expression of miR-92a had superior PFS to the control group (P>0.05) and better OS (P<0.05).

CONCLUSION

Abnormally high expression of miR-92a occurs in colon tumor tissues. Its expression is related to the occurrence, progression, and prognosis of patients with colon cancer. It may be a marker for diagnosis, treatment, and prognosis of disease.

circMTO1 sponges microRNA-219a-5p to enhance gallbladder cancer progression via the TGF-β/Smad and EGFR pathways

Circular mitochondrial translation optimization 1 homologue (circMTO1) has been reported to regulate the tumorigenesis of different types of cancer; however, the role of circMTO1 in gallbladder cancer (GBC) remains unknown. The present study aimed to identify the potential miRNAs and target genes of circMTO1 during GBC progression, and clarify the regulatory mechanism between circMTO1 and miRNAs or target genes. The present study performed MTT and Transwell assays, and Annexin V staining to assess cell viability, migration and apoptosis, respectively. In addition, a lymphatic vessel formation assay was performed to assess tube formation of human dermal lymphatic endothelial cells (HDLECs), and GBC-SD and NOZ cells. The results demonstrated that circMTO1 knockdown significantly attenuated the viability and migration of GBC cells and tube formation of HDLECs, and promoted apoptosis, indicating a tumor-promoting role of circMTO1. In addition, transfection with microRNA (miRNA/miR)-219a-5p inhibitor rescued short hairpin RNA-circMTO1-inhibited tumorigenesis of GBC cells, suggesting that miR-219a-5p acts as a downstream effector for circMTO1. Mechanistically, transfection with miR-219a-5p mimic suppressed the expression levels of Smad2/4 and epidermal growth factor receptor. Analysis of The Cancer Genome Atlas datasets revealed that circMTO1 expression was associated with overall survival and the stage of patients with GBC. Taken together, the results of the present study provide novel insight for the role of circMTO1-induced GBC tumorigenesis via regulation of miR-219a-5p expression.

Circ_0055625 knockdown inhibits tumorigenesis and improves radiosensitivity by regulating miR-338-3p/MSI1 axis in colon cancer

BACKGROUND

Radiotherapy is a main therapeutic method for cancers, including colon cancer. In the current study, we aim to explore the effects of circular RNA (circRNA) circ_0055625 in the progression and radiosensitivity of colon cancer and the underlying mechanism.

METHODS

The expression of circ_0055625 and musashi homolog 1 (MSI1) mRNA was detected by quantitative real-time polymerase chain reaction (qRT-PCR). MSI1 protein expression was determined by Western blot. Cell proliferation was assessed by cell counting kit-8 (CCK-8) and colony formation assays. Cell survival fraction, apoptosis, and invasion were investigated by colony formation assay, flow cytometry analysis, and transwell invasion assay, respectively. Cell migration was detected by wound-healing and transwell migration assays. The binding relationship between microRNA-338-3p (miR-338-3p) and circ_0055625 or MSI1 was predicted by online databases and identified by Dual-Luciferase Reporter Assay. The effects of circ_0055625 silencing on the tumor formation and radiosensitivity of colon cancer in vivo were explored by in vivo tumor formation assay.

RESULTS

Circ_0055625 and MSI1 were upregulated in colon cancer tissues and cells relative to control groups. Radiation treatment apparently increased the expression of circ_0055625 and MSI1 in colon cancer cells. Circ_0055625 knockdown or MSI1 silencing repressed cell proliferation, migration, and invasion and promoted cell apoptosis and radiosensitivity in colon cancer. Also, circ_0055625 silencing-mediated effects were attenuated by MSI1 overexpression. Additionally, circ_0055625 silencing reduced MSI1 expression, which could be attenuated by miR-338-3p inhibitor. Mechanically, circ_0055625 acted as a sponge for miR-338-3p to regulate MSI1. Furthermore, circ_0055625 knockdown hindered tumor growth and improved radiosensitivity in vivo.

CONCLUSION

Circ_0055625 repression inhibited the progression and radioresistance of colon cancer by downregulating MSI1 through sponging miR-338-3p. This result might provide a theoretical basis for improving the therapy of colon cancer with radiation.

Comprehensive Analysis of Correlations in the Expression of miRNA Genes and Immune Checkpoint Genes in Bladder Cancer Cells

Personalised medicine is the future and hope for many patients, including those with cancers. Early detection, as well as rapid, well-selected treatment, are key factors leading to a good prognosis. MicroRNA mediated gene regulation is a promising area of development for new diagnostic and therapeutic methods, crucial for better prospects for patients. Bladder cancer is a frequent neoplasm, with high lethality and lacking modern, advanced therapeutic modalities, such as immunotherapy. MicroRNAs are involved in bladder cancer pathogenesis, proliferation, control and response to treatment, which we summarise in this perspective in response to lack of recent review publications in this field. We further performed a correlation-based analysis of microRNA and gene expression data in bladder cancer (BLCA) TCGA dataset. We identified 27 microRNAs hits with opposite expression profiles to genes involved in immune response in bladder cancer, and 24 microRNAs hits with similar expression profiles. We discuss previous studies linking the functions of these microRNAs to bladder cancer and assess if they are good candidates for personalised medicine therapeutics and diagnostics. The discussed functions include regulation of gene expression, interplay with transcription factors, response to treatment, apoptosis, cell proliferation and angiogenesis, initiation and development of cancer, genome instability and tumour-associated inflammatory reaction.