Long non-coding RNA LINC00958 promotes colorectal cancer progression by enhancing the expression of LEM domain containing 1 via microRNA miR-3064-5p

ALKBH5-induced circular RNA NRIP1 promotes glycolysis in thyroid cancer cells by targeting PKM2

Although circular RNAs (circRNAs) are involved in cell proliferation, differentiation, apoptosis, and invasion, the underlying regulatory mechanisms of circRNAs in thyroid cancer have not been fully elucidated. This article aimed to study the role of circRNA regulated by N6-methyladenosine modification in papillary thyroid cancer (PTC). Quantitative real-time PCR, western blotting, and immunohistochemistry were used to investigate the expressions of circRNA nuclear receptor-interacting protein 1 (circNRIP1) in PTC tissues and adjacent noncancerous thyroid tissues. In vitro and in vivo assays were carried out to assess the effects of circNRIP1 on PTC glycolysis and growth. The N6-methyladenosine mechanisms of circNRIP1 were evaluated by methylated RNA immunoprecipitation sequencing, luciferase reporter gene, and RNA stability assays. Results showed that circNRIP1 levels were significantly upregulated in PTC tissues. Furthermore, elevated circNRIP1 levels in PTC patients were correlated with high tumor lymph node metastasis stage and larger tumor sizes. Functionally, circNRIP1 significantly promoted glycolysis, PTC cell proliferation in vitro, and tumorigenesis in vivo. Mechanistically, circNRIP1 acted as a sponge for microRNA (miR)-541-5p and miR-3064-5p and jointly upregulated pyruvate kinase M2 (PKM2) expression. Knockdown of m⁶ A demethylase α-ketoglutarate-dependent dioxygenase alkB homolog 5 (ALKBH5) significantly enhanced circNRIP1 m⁶ A modification and upregulated its expression. These results show that ALKBH5 knockdown upregulates circNRIP1, thus promoting glycolysis in PTC cells. Therefore, circNRIP1 can be a prognostic biomarker and therapeutic target for PTC by acting as a sponge for oncogenic miR-541-5p and miR-3064-5p to upregulate PKM2 expression.

LINC00958 may be a new prognostic biomarker in various cancers: A meta-analysis and bioinformatics analysis

Background: There have been many studies on long non-coding RNAs (lncRNAs) as tumor markers. LINC00958 is a lncRNA that has been studied in a variety of tumor types. This meta-analysis aims to explore the relationship between LINC00958 and clinical prognosis and pathological characteristics in various cancers. Methods: We searched for related studies from PubMed, Web of Science, The Cochrane Library and Embase (up to October 2021). The association of LINC00958 expression with clinicopathological characteristics and prognosis was evaluated using the pooled odds ratios (ORs) or hazard ratios (HRs) with 95% confidence intervals (CIs). Results: 16 studies (1,121 patients) were included in this meta-analysis, we found that overexpression of LINC00958 was associated with poor overall survival (OS) (HR = 1.84; 95% CI: 1.36-2.49; p < 0.001). We also found that LINC00958 overexpression was correlated with positive lymph node metastasis (LNM) (OR = 1.91; 95% CI: 1.39-2.63; p < 0.001), advanced degree of infiltration (OR = 1.64; 95% CI: 1.11-2.41; p = 0.013), advanced tumor-node-metastasis (TNM) stage (OR = 2.80; 95% CI: 1.48-5.33; p = 0.002). Other clinicopathological characteristics have no obvious correlation, such as age, sex, tumor size, distant metastasis, and differentiation grade (p > 0.05). Conclusion: In summary, the overexpression of LINC00958 is significantly correlated with poor OS, positive LNM, advanced degree of infiltration, and advanced TNM stage. LINC00958 might serve as a potential prognostic biomarker and therapeutic target for a variety of cancers. However, rigorous studies with large sample sizes are still needed for further research and demonstration.

LncRNA LAMTOR5-AS1 sponges miR-210-3p and regulates cervical cancer progression

AIM

Cervical cancer has attracted increasing attention in recent years, and the incidence has shown a trend of younger age. Therefore, it is an effective method to regulate the progression of cervical cancer through new prognostic biomarkers. The purpose of this study was to evaluate the potential of lncRNA LAMTOR5-AS1 (LAMTOR5-AS1) as a prognostic biomarker and reveal its regulatory role in cervical cancer.

METHODS

A total of 120 patients with cervical cancer were selected as research subjects to verify the prognostic effect of LAMTOR5-AS1 in a series of experiments. The expression of LAMTOR5-AS1 in cervical cancer tissues and cells was determined by polymerase chain reaction assay. The proliferation, migration, and invasion ability of cervical cancer cells were evaluated by Cell Counting Kit-8 (CCK-8) and Transwell assay. Luciferase reporter gene detection was used to determine the mechanism of LAMTOR5-AS1 targeting miR-210-3p, and to reflect the prognostic value of LAMTOR5-AS1 according to statistical methods.

RESULTS

LAMTOR5-AS1 decreased in cervical cancer tissues, while miR-210-3p expression increased. In the study of cervical cancer cells, it was found that the LAMTOR5-AS1 sponge miR-210-3p was associated with the malignant progression of cervical cancer. Overexpression of LAMTOR5-AS1 could effectively inhibit the development of cervical cancer cells and might be chosen as a prognostic biomarker of cervical cancer.

CONCLUSIONS

LAMTOR5-AS1 sponges miR-210-3p and modulates the progression of cervical cancer, which predict the prognosis of cervical cancer patients.

miR-145-3p Hampers the Malignant Progression of Esophageal Carcinoma via CXCL5 Downregulation

Esophageal carcinoma (EC) is the most prevalent malignant tumor that occurs frequently worldwide. The early diagnostic biomarkers are crucial for EC treatment. miRNA can regulate EC progression, with diagnostic and prognostic value. Herein, differentially expressed miRNAs and mRNAs (DEmRNAs) in EC were predicted based on TCGA database. The target mRNAs of miRNA were predicted through databases, which were then intersected with DEmRNAs. Next, the correlation between miRNA and candidate mRNAs was analyzed. qRT-PCR was introduced to analyze expression of miR-145-3p and CXCL5 mRNA in EC cell lines, and western blot was performed to assess protein expression of CXCL5. Cell proliferation, migration, invasion, and apoptosis in EC were examined through CCK-8, wound healing, Transwell invasion, and flow cytometry assays. Moreover, targeting relationship between miR-145-3p and CXCL5 was verified through luciferase reporter gene analysis. The experimental results revealed a decreased miR-145-3p expression and an increased CXCL5 expression in EC. Enforced expression of miR-145-3p hindered proliferation, migration, invasion, and stimulated apoptosis of EC cells by repressing CXCL5. This study manifested that miR-145-3p may be a tumor suppressor in EC, and miR-145-3p/CXCL5 axis restrained the malignant progression of EC. These results supply an underlying target for prognosis and treatment of EC patients.

LINC00958: A promising long non-coding RNA related to cancer

Long non-coding RNAs (lncRNAs), a class of RNA transcripts longer than 200 nucleotides, do not encode proteins; however, they encode small peptides and micropeptides that act as bioactive peptides with notable effects in regulating the progression of malignant tumors, such as lung and colorectal cancers, and affecting patient prognosis. lncRNAs are important intracellular regulators, particularly in tumorigenesis and tumor progression. Long intergenic non-protein coding RNA958 (LINC00958), which has received increasing attention in recent years, is highly expressed in various malignancies, including head and neck squamous cell carcinoma (HNSC), non-small-cell lung cancer (NSCLC), gastric cancer, hepatocellular carcinoma (HCC), colorectal cancer, bladder cancer, and breast cancer. Here, we reviewed the recent studies on LINC00958 as well as its closely related clinical features and functional regulation in cancers. We systematically expounded the molecular mechanisms underlying the biological functions of LINC00958 in inhibiting cell apoptosis and enhancing the chemoradiotherapy resistance of tumor cells. The upregulation of LINC00958 enhances the resistance of tumor cells to radiotherapy and chemotherapy and induces lymphangiogenesis. Moreover, it is involved in tumor glycolytic metabolism, which plays a crucial role in facilitating the proliferation, invasion, and migration of tumor cells. Additionally, analysis of various studies revealed that LINC00958 acts as an endogenous competitive RNA (ceRNA) and regulates the malignant behavior of tumor cells through the miRNA-mRNA axis. Collectively, the use of LINC00958 as a novel biomarker and therapeutic target for the clinical diagnosis and treatment of different cancers has bright prospects in the future.

LEM domain containing 1 (LEMD1) transcriptionally activated by SRY-related high-mobility-group box 4 (SOX4) accelerates the progression of colon cancer by upregulating phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway

Colon cancer is a highly malignant tumor in the digestive system. LEM domain containing 1 (LEMD1) is supposed to be a survival marker of poor prognosis in colon cancer. We aimed to explore the role and mechanism of LEMD1 in colon cancer progression. GEPIA database analyzed LEMD1 expression in colon cancer tissues and prognosis of colon cancer patients. LEMD1 expression in tumor cells was tested by RT-qPCR and western blotting. Proliferation of colon cancer cells was estimated by CCK-8 and colony formation assays. Transwell and wound healing assays were used to appraise the cell invasion and migration. Meanwhile, tube formation assays were used to evaluate angiogenesis. The possible binding sites between SRY-related high-mobility-group box 4 (SOX4) and LEMD1 were predicted by JASPAR database. Besides, SOX4 expression in colon cancer tissues and the correlation between SOX4 and LEMD1 were examined using the GEPIA database. Luciferase reporter and ChIP assays were used to verify the interaction between SOX4 and LEMD1. The expression of proteins in PI3K/Akt signaling was evaluated by western blotting. LEMD1 was overexpressed in colon cancer tissues and cells and associated with poor prognosis. Functionally, LEMD1 deficiency impeded the proliferation, migration, invasion and angiogenesis of colon cancer cells. Additionally, SOX4 had a positive correlation with LEMD1 and could bind to LEMD1 promoter. Rescue assays validated that SOX4 elevation reversed the suppressive role of LEMD1 deletion in the development of colon cancer and the expression of p-PI3K and p-AKT. Collectively, LEMD1 induced by SOX4 drove the progression of colon cancer by activating PI3K/Akt signaling.