Clinical significance and functions of miR-203a-3p/AVL9 axis in human non-small-cell lung cancer

Plasma Exosome miR-203a-3p is a Potential Liquid Biopsy Marker for Assessing Tumor Progression in Breast Cancer Patients

Background

Timely detection of tumor progression in breast cancer (BC) patients is critical for therapeutic management and prognosis. Plasma exosomal miRNAs are potential liquid biopsy markers for monitoring tumor progression, but their roles in BC remain unclear.

Methods

In the TCGA database, we first screened for miRNAs significantly associated with BC progression by comparing miRNA expression in para-carcinoma tissues, stage I BC tissues, and stage II-III BC tissues (n = 1026). Cox regression analyses and survival analyses were performed on candidate miRNAs to explore their prognostic value (n = 848). KEGG, GO, and PPI analyses were used to identify enriched pathways associated with cancer. Finally, the potential of candidate miRNAs as liquid biopsy markers was evaluated by sequencing and analyzing plasma exosomal miRNAs from our collection of 45 BC patients (14 in stage I, 31 in stage II-III) and 5 healthy controls, combined with qRT-PCR analysis to assess the correlation of candidate gene expression in plasma exosomes and BC tissues.

Results

We found that only miR-203a-3p was progressively elevated with BC progression and was associated with poor prognosis in the TCGA dataset. Its potential target genes were enriched in pathways related to tumor progression, and the downregulation of 48 of these genes was associated with poor prognosis. More importantly, plasma exosomal miR-203a-3p was also found to gradually increase with BC progression, and its expression was positively correlated with miR-203a-3p in BC tissues. This result suggests that plasma exosomal miR-203a-3p may reflect the expression of miR-203a-3p in tumor tissues and serve as a potential liquid biopsy marker for monitoring BC progressions.

Conclusion

We found for the first time that elevated miR-203a-3p was associated with BC progression and poor prognosis. Our findings suggested that plasma exosomal miR-203a-3p could hold potential as a liquid biopsy marker for evaluating BC progression in patients.

miR-203a-A multifaceted regulator modulating cancer hallmarks and therapy response

MicroRNAs (miRNAs) are a class of noncoding RNAs of about 19-25 nucleotides, which serve as critical modulators of various cellular and biological processes by target gene regulation. Dysregulated expression of miRNAs modulates the pathophysiology of various human diseases, including cancer. Among miRNAs, miR-203a is one of the most extensively researched dysregulated miRNAs in different cancers. Our review investigated the roles of miR-203a in the hallmarks of cancer modulating different pathways through target gene regulations, chemoresistance, its crosstalk with other ncRNAs or genes in terms of ceRNAs impacting oncogenesis, and its potential applications in the diagnosis, prognosis, and chemotherapeutic responses in different cancer types. miR-203a impacts cancer cell behavior by regulating these exclusive hallmarks- sustaining proliferation, cell growth, invasion and metastasis, cell death, and angiogenesis. Besides, miR-203a is found in human circulating biofluids like plasma or serum of colorectal cancer, cervical cancer, and hepatocellular carcinoma, hinting at its potential as a biomarker. Further, miR-203a is involved in enhancing the chemosensitivity of cisplatin, docetaxel, paclitaxel, doxorubicin, and 5-fluorouracil in a variety of malignancies through their cognate target genes. These results suggest that miR-203a is a crucial multifaceted miRNA that controls cancer cell proliferation, metastasis, and chemotherapy response, shedding new light on its possible application.

A novel lactate metabolism-related signature predicts prognosis and tumor immune microenvironment of breast cancer

Background: Lactate, an intermediate product of glycolysis, has become an essential regulator of tumor maintenance, development, and metastasis. Lactate can drive tumors by changing the microenvironment of tumor cells. Because of lactate's important role in cancer, we aim to find a novel prognostic signature based on lactate metabolism-related genes (LMRGs) of breast cancer (BC). Methods: RNA-sequencing data and clinical information of BC were enrolled from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. We obtained LMRGs from the Molecular Signature Database v7.4 and articles, and then we compared candidate genes with TCGA data to get differential genes. Univariate analysis and most minor absolute shrinkage and selector operator (LASSO) Cox regression were employed to filter prognostic genes. A novel lactate metabolism-related risk signature was constructed using a multivariate Cox regression analysis. The signature was validated by time-dependent ROC curve analyses and Kaplan-Meier analyses in TCGA and GEO cohorts. Then, we further investigated in depth the function of the model's immune microenvironment. Results: We constructed a 3-LMRG-based risk signature. Kaplan-Meier curves confirmed that high-risk score subgroups had a worse prognosis in TCGA and GEO cohorts. Then a nomogram to predict the probability of survival for BC was constructed. We also performed Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway function analysis. The function analysis showed that the lactate metabolism-related signature was significantly related to immune response. A significant correlation was observed between prognostic LMRGs and tumor mutation burden, checkpoints, and immune cell infiltration. An mRNA-miRNA network was built to identify an miR-203a-3p/LDHD/LYRM7 regulatory axis in BC. Conclusion: In conclusion, we constructed a novel 3-LMRG signature and nomogram that can be used to predict the prognosis of BC patients. In addition, the signature is closely related to the immune microenvironment, which may provide new insight into future anticancer therapies.

MALAT1-miRNAs network regulate thymidylate synthase and affect 5FU-based chemotherapy

Background

The active metabolite of 5-Fluorouracil (5FU), used in the treatment of several types of cancer, acts by inhibiting the thymidylate synthase encoded by the TYMS gene, which catalyzes the rate-limiting step in DNA replication. The major failure of 5FU-based cancer therapy is the development of drug resistance. High levels of TYMS-encoded protein in cancerous tissues are predictive of poor response to 5FU treatment. Expression of TYMS is regulated by various mechanisms, including involving non-coding RNAs, both miRNAs and long non-coding RNAs (lncRNAs).

Aim

To delineate the miRNAs and lncRNAs network regulating the level of TYMS-encoded protein.

Main body

Several miRNAs targeting TYMS mRNA have been identified in colon cancers, the levels of which can be regulated to varying degrees by lncRNAs. Due to their regulation by the MALAT1 lncRNA, these miRNAs can be divided into three groups: (1) miR-197-3p, miR-203a-3p, miR-375-3p which are downregulated by MALAT1 as confirmed experimentally and the levels of these miRNAs are actually reduced in colon and gastric cancers; (2) miR-140-3p, miR-330-3p that could potentially interact with MALAT1, but not yet supported by experimental results; (3) miR-192-5p, miR-215-5p whose seed sequences do not recognize complementary response elements within MALAT1. Considering the putative MALAT1-miRNAs interaction network, attention is drawn to the potential positive feedback loop causing increased expression of MALAT1 in colon cancer and hepatocellular carcinoma, where YAP1 acts as a transcriptional co-factor which, by binding to the TCF4 transcription factor/ β-catenin complex, may increase the activation of the MALAT1 gene whereas the MALAT1 lncRNA can inhibit miR-375-3p which in turn targets YAP1 mRNA.

Conclusion

The network of non-coding RNAs may reduce the sensitivity of cancer cells to 5FU treatment by upregulating the level of thymidylate synthase.

Characterization of the MicroRNA Cargo of Extracellular Vesicles Isolated from a Pulmonary Tumor-Draining Vein Identifies miR-203a-3p as a Relapse Biomarker for Resected Non-Small Cell Lung Cancer

In resected non-small cell lung cancer (NSCLC), post-surgical recurrence occurs in around 40% of patients, highlighting the necessity to identify relapse biomarkers. An analysis of the extracellular vesicle (EV) cargo from a pulmonary tumor-draining vein (TDV) can grant biomarker identification. We studied the pulmonary TDV EV-miRNAome to identify relapse biomarkers in a two-phase study (screening and validation). In the screening phase, a 17-miRNA relapse signature was identified in 18 selected patients by small RNAseq. The most expressed miRNA from the signature (EV-miR-203a-3p) was chosen for further validation. Pulmonary TDV EV-miR-203a-3p was studied by qRT-PCR in a validation cohort of 70 patients, where it was found to be upregulated in relapsed patients (p = 0.0194) and in patients with cancer spread to nearby lymph nodes (N+ patients) (p = 0.0396). The ROC curve analysis showed that TDV EV-miR-203a-3p was able to predict relapses with a sensitivity of 88% (AUC: 0.67; p = 0.022). Moreover, patients with high TDV EV-miR-203a-3p had a shorter time to relapse than patients with low levels (43.6 vs. 97.6 months; p = 0.00703). The multivariate analysis showed that EV-miR-203a-3p was an independent, predictive and prognostic post-surgical relapse biomarker. In conclusion, pulmonary TDV EV-miR-203a-3p is a promising new relapse biomarker for resected NSCLC patients.

Hsa_circ_0017639 regulates cisplatin resistance and tumor growth via acting as a miR-1296-5p molecular sponge and modulating sine oculis homeobox 1 expression in non-small cell lung cancer

Cisplatin (DDP)-induced chemoresistance is an important reason for the failure of non-small cell lung cancer (NSCLC) treatment. Circular RNAs (circRNAs) participate in the chemoresistance of diverse cancers. However, the function of hsa_circ_0017639 (circ_0017639) in the DDP resistance of NSCLC is unclear. Forty-one NSCLC samples (21 DDP-resistant samples and 20 DDP-sensitive samples) were utilized in the research. The relative expression levels of some genes were determined by real-time quantitative polymerase chain reaction (RT-qPCR). 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay for half-maximal inhibitory concentration (IC₅₀) value of DDP and cell viability, colony formation and 5-ethynyl-2’-deoxyuridine (EDU) assays for cell proliferation, flow cytometry assay for cell apoptosis, transwell assay for cell invasion and wound-healing assay for cell migration were performed. The regulation mechanism of circ_0017639 was demonstrated by a dual-luciferase reporter assay. We observed higher levels of circ_0017639 in DDP-resistant NSCLC samples and cells. Functionally, circ_0017639 silencing decreased tumor growth and elevated DDP sensitivity in vivo and induced apoptosis, repressed proliferation, invasion, and migration of DDP-resistant NSCLC cells in vitro. Mechanically, circ_0017639 modulated sine oculis homeobox 1 (SIX1) expression via sponging microRNA (miR)-1296-5p. Also, miR-1296-5p inhibitor restored circ_0017639 knockdown-mediated impacts on cell DDP resistance in DDP-resistant NSCLCs. Furthermore, SIX1 overexpression counteracted the inhibiting impact of miR-1296-5p upregulation on DDP resistance and malignant phenotypes of DDP-resistant NSCLC cells. In conclusion, circ_0017639 conferred DDP resistance and promoted tumor growth via elevating SIX1 expression through sequestering miR-1296-5p in NSCLC, providing a new mechanism for understanding the chemoresistance and progression of NSCLC.

Circ_0006220 promotes non-small cell lung cancer progression via sponging miR-203-3p and regulating RGS17 expression

BACKGROUND

Lung cancer is the most common malignancy, and its mortality ranks first among malignancies. Non-small cell lung carcinoma (NSCLC) is the most common pathological subtype of lung cancer. It is reported that circular RNAs (circRNAs) feature prominently in the occurrence and metastasis of NSCLC.

PURPOSE

This study aims to decipher the biological functions of circ_0006220 in NSCLC and the underlying mechanism.

METHODS

The microarray data (GSE101586) were downloaded from the Gene Expression Omnibus database, and differentially expressed circRNAs in NSCLC tissues were screened using the GEO2R tool. Quantitative real-time polymerase chain reaction was used for detecting the expression of circ_0006220, miR-203-3p, and regulator of G-protein signaling 17 (RGS17) mRNA in NSCLC tissues and cells. The connection between circ_0006220 expression and clinicopathological indicators was analyzed through the chi-square test. EdU and cell counting kit-8 assays were carried out to detect cell growth. Cell migration and invasion were detected by transwell assays. Bioinformatics was used to predict, and RNA immunoprecipitation assay and dual-luciferase reporter gene assay were conducted for verifying, the targeted relationship among circ_0006220, miR-203-3p, and RGS17.

RESULTS

The expression of circ_0006220 was elevated in NSCLC cells and tissues, and high circ_0006220 expression was significantly associated with unfavorable clinicopathological indicators. In addition, it was revealed that circ_0006220 overexpression facilitated NSCLC cell growth, migration, and invasion, whereas knocking down circ_0006220 had contrary effects. Furthermore, miR-203-3p was identified as a downstream target of circ_0006220, and circ_0006220 could sponge miR-203-3p; RGS17 was identified as a downstream target of miR-203-3p and was positively modulated by circ_0006220.

CONCLUSIONS

Circ_0006220 up-regulates RGS17 expression by adsorbing miR-203-3p to promote NSCLC development.

AVL9 promotes colorectal carcinoma cell migration via regulating EGFR expression

Background

Despite advanced treatments could inhibit progression of colorectal carcinoma (CRC), the recurrence and metastasis remain challenging issues. Accumulating evidences implicated that AVL9 played a vital role in human cancers, but it’s biological function and mechanism in CRC remain unclear.

Aim

To investigate the biological role and mechanism of AVL9 in colorectal carcinoma.

Results

AVL9 expression was significantly upregulated in tumor tissues than that in matched normal tissues both at mRNA and protein levels. High expression of AVL9 was closely correlated with M status, stages and poor prognosis of colorectal carcinoma (CRC) patients. Functionally, AVL9 overexpression promoted cell migration rather than cell proliferation in vitro, whereas AVL9 knockdown exhibited the contrary results. Mechanistically, AVL9 regulated EGFR expression, and knockdown of EGFR restrained AVL9-induced cell migration.

Conclusion

These findings demonstrated that AVL9 contributed to CRC cell migration by regulating EGFR expression, suggesting a potential biomarker and treatment target for CRC.

AVL9 is Upregulated in and Could Be a Predictive Biomarker for Colorectal Cancer

PURPOSE

This study aimed to explore the function and clinical significance of AVL9 in colorectal cancer (CRC).

MATERIALS AND METHODS

The GEO, TCGA, and GEPIA databases were searched to evaluate the expression level of AVL9, while the SurvExpress online tool was used to explore its related clinical survival prognosis. The cBioPortal and LinkedOmics databases were used to identify AVL9 expression-related genes. Protein-protein interaction (PPI) networks were analyzed using Cytoscape 3.7.1 and DAVID6.8, which was used to perform Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) signal pathway enrichment. The immunohistochemistry of AVL9 in CRC was detected using an online tool protein atlas. RNA isolation and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assays were used to detect AVL9 expression in tissue and plasma samples.

RESULTS

Our study confirmed that AVL9 was highly expressed in CRC lesions versus the adjacent normal tissues (P < 0.001). High AVL9 expression was negatively associated with survival outcomes (P < 0.05). GO analysis showed that AVL9 expression-related genes were enriched in single organismal cell-cell adhesion, post-transcriptional regulation of gene expression, and negative regulation of the vascular endothelial growth factor receptor signaling pathway (P < 0.05). On a KEGG pathway analysis, these genes were mainly involved in progesterone-mediated oocyte maturation, axon guidance, the insulin signaling pathway, and the ubiquitin-mediated proteolysis signaling pathways (P < 0.05). In the PPI analysis, the KBTBD2, KIAA1147, EPDR1, and RNF216 genes interacted with AVL9, and GEPIA predicted that their expression levels were all positively correlated with AVL9. Furthermore, a clinicopathological parameter analysis found that high AVL9 expression was positively correlated with differentiation and TNM stage. RT-qPCR analysis further showed that plasma AVL9 expression was upregulated in CRC patients versus healthy controls.

CONCLUSION

AVL9 could serve as a potential biomarker and therapeutic target for CRC.