Inhibition of MicroRNA-381 Promotes Tumor Cell Growth and Chemoresistance in Clear-Cell Renal Cell Carcinoma

Non-coding RNAs in renal cell carcinoma: Implications for drug resistance

Renal cell carcinoma (RCC) represents a malignant tumor of the urinary system. Individuals with early-stage RCC could be cured by surgical treatment, but a considerable number of cases of advanced RCC progress to drug resistance. Recently, numerous reports have demonstrated that a variety of non-coding RNAs (ncRNAs) contribute to tumor occurrence and development. ncRNAs can act as oncogenic or tumor suppressor genes to regulate proliferation, migration, drug resistance and other processes in RCC cells through a variety of signaling pathways. Considering the lack of treatment options for advanced RCC after drug resistance, ncRNAs may be a good choice as biomarkers of drug resistance in RCC and targets to overcome drug resistance. In this review, we discussed the effects of ncRNAs on drug resistance in RCC and the great potential of ncRNAs as a biomarker of or a new therapeutic method in RCC.

Mining database and verification of PIK3CB as a marker predicting prognosis and immune infiltration in renal clear cell carcinoma

BACKGROUND

Kidney renal clear cell carcinoma (KIRC) was the most prevalent malignancy of urinary system. Phosphatidylinositol 3-kinase pathway exerted a vital function in tumor proliferation, invasion, and survival by integrating extracellular growth signals.

METHODS

The expression and clinical significance of PIK3CB in KIRC was explored using bioinformatics analysis. And qRT-PCR was performed to verify our results.

RESULTS

PIK3CB was downregulated at mRNA and protein level in KIRC. KIRC patients with low PIK3CB expression indicated a worse overall survival, progression free survival, and disease-free survival. A predictive nomogram was constructed and demonstrated that the predicted calibration plots for 1-year, 3-year, and 5-year OS probabilities showed good agreement compared with the actual OS of KIRC patients. Validation research demonstrated a downregulation of PIK3CB in KIRC tissues and a poor overall survival in KIRC patients with low PIK3CB expression. Furthermore, Cox regression analysis revealed that PIK3CB expression was an independent prognostic factor for KIRC. PIK3CB expression showed positive correlation with the abundance of immune cells. Moreover, enrichment analysis revealed that PIK3CB and associated genes were mainly associated with RNA splicing and JAK-STAT signaling pathway.

CONCLUSION

Our study suggested that PIK3CB was a potential biomarker for prognosis and correlated with immune infiltrates in KIRC.

CPNE1 is a potential prognostic biomarker, associated with immune infiltrates and promotes progression of hepatocellular carcinoma

BACKGROUND

Copine1 (CPNE1), the first discovered CPNE1 family member, participates in the process of carcinogenesis and development of diverse tumors. Our study aimed to investigate the expression and prognostic value of CPNE1 gene in hepatocellular carcinoma (HCC), to explore its functional network in HCC and its effects on biological behaviors.

METHODS

HCCDB, CCLE, HPA and LinkedOmics online databases were used to explore the expression of CPNE1 gene and analyze the co-expression network of CPNE1 in hepatocellular carcinoma. Gene set enrichment analysis (GSEA) was used for GO functional annotation, KEGG pathway enrichment analysis and regulators of CPNE1 networks in LIHC. HepG2 and MHCC-97H cells were selected to construct CPNE1 knockdown cell lines by transfection with siRNA, and Hep3B cell was selected to construct CPNE1 overexpression cell line by transfection with plasmid. The effect of CPNE1 on the proliferation of hepatocellular carcinoma cells was examined by CCK8 assay and clone formation assay; the effect of CPNE1 on the migration ability of hepatocellular carcinoma cells was assessed by cell scratch assay and Transwell cell migration assay; finally, the expression of related signaling pathway proteins was examined by Western Blot. The correlation of CPNE1 expression with immune infiltration and immune checkpoint molecules in HCC tissues was analyzed using TIMER online database and GSEA.

RESULTS

CPNE1 was highly expressed in HCC tissues and significantly correlated with sex, age, cancer stage and tumor grade. Overall survival (OS) was significantly lower in patients with high CPNE1 expression than in patients with low CPNE1 expression, and CPNE1 could be used as an independent prognostic indicator for HCC. Knockdown of CPNE1 gene inhibited the AKT/P53 pathway, resulting in decreased proliferation, migration and invasion of HCC cells. Overexpression of CPNE1 gene showed the opposite results. The level of CPNE1 expression in HCC was significantly and positively correlated with the level of infiltration of B cells, CD8⁺ T cells, CD4⁺ T cells, macrophages, neutrophils, and dendritic cells (P < 0.001). GSEA results also showed that CPNE1 of LIHC was involved in some immune response regulating signaling pathways.

CONCLUSIONS

Our study firstly found the expression of CPNE1 was significantly higher in LIHC tissues than in normal liver tissues, and high CPNE1 expression was associated with poor prognosis. In addition, we identified the possible mechanism by which CPNE1 functioned in LIHC. CPNE1 influenced AKT/P53 pathway activation and LIHC cell proliferation and migration. There was a significant correlation between CPNE1 expression and tumor immune infiltration in LIHC.

MicroRNA-381 in human cancer: Its involvement in tumour biology and clinical applications potential

MicroRNAs (miRNAs) are small non‐coding RNAs that regulate gene expression at the post‐transcriptional level. MiRNAs are involved in the development and progression of a wide range of cancers. Among such cancer‐associated miRNAs, miR‐381 has been a major focus of research. The expression pattern and role of miR‐381 vary among different cancer types. MiR‐381 modulates various cellular behaviours in cancer, including proliferation, apoptosis, cell cycle progression, migration and invasion. MiR‐381 is also involved in angiogenesis and lymphangiogenesis, as well as in the resistance to chemotherapy and radiotherapy. MiR‐381 itself is regulated by several factors, such as long noncoding RNAs, circular RNAs and cytokines. Aberrant expression of miR‐381 in blood samples indicates that it can be used as a diagnostic marker in cancer. Tissue miR‐381 expression may serve as a prognostic factor for the clinicopathological characteristics of cancers and survival of patients. Metformin and icaritin regulate miR‐381 expression and present anticancer properties. This review comprehensively summarizes the effect of miR‐381 on tumour biological behaviours, as well as the clinical application potential of miR‐381 for the treatment of cancer.

Circulating microRNAs from the Molecular Mechanisms to Clinical Biomarkers: A Focus on the Clear Cell Renal Cell Carcinoma

microRNAs (miRNAs) are emerging as relevant molecules in cancer development and progression. MiRNAs add a post-transcriptional level of control to the regulation of gene expression. The deregulation of miRNA expression results in changing the molecular circuitry in which miRNAs are involved, leading to alterations of cell fate determination. In this review, we describe the miRNAs that are emerging as innovative molecular biomarkers from liquid biopsies, not only for diagnosis, but also for post-surgery management in cancer. We focus our attention on renal cell carcinoma, in particular highlighting the crucial role of circulating miRNAs in clear cell renal cell carcinoma (ccRCC) management. In addition, the functional deregulation of miRNA expression in ccRCC is also discussed, to underline the contribution of miRNAs to ccRCC development and progression, which may be relevant for the identification and design of innovative clinical strategies against this tumor.

Functional roles of exosomal miRNAs in multi-drug resistance in cancer chemotherapeutics

Recent understanding of different molecular aspects of tumor initiation and progression has led to the discovery of a growing list of drugs. While these drugs have shown promising effects on tumor cells, their widespread usage has been hampered by the acquisition of drug resistance in a subpopulation of tumor cells. A differential pattern in the secretion of specialized vesicles named "exosomes" in drug-resistant cancer cells have recently received much attention. In addition, microRNAs (miRNAs) have been shown to be enriched in exosomes. Exosomal miRNAs (also known as exo-miRs) could be shuttled to recipient cells and play a role in the regulation of post-transcriptional gene expression, which may exert certain effects on cancer drug resistance. Here, we have reviewed the role of exo-miRs in chemotherapeutic resistance in different cancer types. Besides, studies which have focused on predictive role of circulating exo-miRs in cancer drug resistance are reviewed.

MicroRNA Signature in Renal Cell Carcinoma

Renal cell carcinoma (RCC) includes 2.2% of all diagnosed cancers and 1.8% of cancer-related mortalities. The available biomarkers or screening methods for RCC suffer from lack of sensitivity or high cost, necessitating identification of novel biomarkers that facilitate early diagnosis of this cancer especially in the susceptible individuals. MicroRNAs (miRNAs) have several advantageous properties that potentiate them as biomarkers for cancer detection. Expression profile of miRNAs has been assessed in biological samples from RCC patients. Circulatory or urinary levels of certain miRNAs have been proposed as markers for RCC diagnosis or follow-up. Moreover, expression profile of some miRNAs has been correlated with response to chemotherapy, immunotherapy or targeted therapeutic options such as sunitinib. In the current study, we summarize the results of studies that assessed the application of miRNAs as biomarkers, therapeutic targets or modulators of response to treatment modalities in RCC patients.

MicroRNA-381-A Key Transcriptional Regulator: Its Biological Function and Clinical Application Prospects in Cancer

MicroRNAs (miRNAs) are small non-coding RNA molecules that function by regulating messenger RNAs. Recent studies have shown that miRNAs play important roles in multiple processes of cancer development. MiR-381 is one of the most important miRNAs in cancer progression. MiR-381 is downregulated in some cancers and upregulated in other cancers, including glioma, epithelial sarcoma, and osteosarcoma. MiR-381 regulates epithelial-mesenchymal transition (EMT), chemotherapeutic resistance, radioresistance, and immune responses. Thus, miR-381 participates in tumor initiation, progression, and metastasis. Moreover, miR-381 functions in various oncogenic pathways, including the Wnt/β-catenin, AKT, and p53 pathways. Clinical studies have shown that miR-381 could be considered a biomarker or a novel prognostic factor. Here, we summarize the present studies on the role of miR-381 in cancer development, including its biogenesis and various affected signaling pathways, and its clinical application prospects. MiR-381 expression is associated with tumor stage and survival time, making miR-381 a novel prognostic factor.

Identification of the miRNA-mRNA regulatory pathways and a miR-21-5p based nomogram model in clear cell renal cell carcinoma

Background

The purpose of this study was to determine the key microRNAs (miRNAs) and their regulatory networks in clear cell renal cell carcinoma (ccRCC).

Methods

Five mRNA and three microRNA microarray datasets were downloaded from the Gene Expression Omnibus database and used to screen the differentially expressed miRNAs (DEMs) and differentially expressed genes (DEGs). Gene ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis were performed with Metascape. A miRNA-mRNA network was mapped with the Cytoscape tool. The results were validated with data from The Cancer Genome Atlas (TCGA) and qRT-PCR. A nomogram model based on independent prognostic key DEMs, stage and grade was constructed for further investigation.

Results

A total of 26 key DEMs and 307 DEGs were identified. Dysregulation of four key DEMs (miR-21-5p, miR-142-3p, miR-155-5p and miR-342-5p) was identified to correlate with overall survival. The results were validated with TCGA data and qRT-PCR. The nomogram model showed high accuracy in predicting the prognosis of patients with ccRCC.

Conclusion

We identified 26 DEMs that may play vital roles in the regulatory networks of ccRCC. Four miRNAs (miR-21-5p, miR-142-3p, miR-155-5p and miR-342-5p) were considered as potential biomarkers in the prognosis of ccRCC, among which only miR-21-5p was found to be an independent prognostic factor. A nomogram model was then created on the basis of independent factors for better prediction of prognosis for patients with ccRCC. Our results suggest a need for further experimental validation studies.