Oncogenesis and Tumor Inhibition by MicroRNAs and its Potential Therapeutic Applications: A Systematic Review

Differential Expression of MicroRNA MiR-145 and MiR-155 Downstream Targets in Oral Cancers Exhibiting Limited Chemotherapy Resistance

New evidence has suggested that non-coding microRNAs play a significant role in mediating and modulating chemotherapy resistance, particularly among oral cancers. One recent study found that the upregulation of miR-145 and the downregulation of miR-155 strongly correlated with a limited chemotherapy resistance to Cisplatin, 5-Fluorouracil, and Paclitaxel, although the mechanism(s) responsible for these observations remain unidentified. Using commercially available cell lines of oral squamous cell carcinoma, RNA was isolated, converted into cDNA, and subsequently screened for the expression of downstream targets of miR-145 and miR-155 using qPCR. These results demonstrated the upregulation of miR-21, miR-125, miR-133, miR-365, miR-720, and miR-1246, as well as the downregulation of miR-140, miR-152, miR-218, miR-221, and miR-224. This screening also confirmed the differential expression and regulation of mir-145 and miR-155 among the cell lines with limited chemotherapy resistance (SCC15). In addition, several downstream targets of these specific microRNAs were upregulated by all oral cancer cell lines, such as MBTD1 and FSCN1, or downregulated in all cell lines, such as CLCN3, FLI-1, MRTFB, DAB, SRGAP1, and ABHD17C. However, three miR-145 downstream targets were identified in the least chemotherapy-resistant cells, exhibiting the differential upregulation of KCNA4 and SRGAP2, as well as the downregulation of FAM135A, with this expression pattern not detected in any of the other oral cancer cell lines. These data strongly support that the differential regulation of these three downstream targets may be related to the chemosensitivity of this oral cancer cell line. The potential involvement of these targets must be further investigated to determine how and whether mechanisms of these cellular pathways may be involved in the observed lack of chemotherapy resistance. These data may be important to design targets or treatments to reduce chemotherapy resistance and improve patient treatment outcomes.

A comprehensive survey into the role of microRNAs in ovarian cancer chemoresistance; an updated overview

Ovarian cancer (OC), a frequent malignant tumor that affects women, is one of the leading causes of cancer-related death in this group of individuals. For the treatment of ovarian cancer, systemic chemotherapy with platinum-based drugs or taxanes is the first-line option. However, drug resistance developed over time during chemotherapy medications worsens the situation. Since uncertainty exists for the mechanism of chemotherapy resistance in ovarian cancer, there is a need to investigate and overcome this problem. miRNAs are engaged in various signaling pathways that contribute to the chemotherapeutic resistance of ovarian cancer. In the current study, we have tried to shed light on the mechanisms by which microRNAs contribute to the drug resistance of ovarian cancer and the use of some microRNAs to combat this chemoresistance, leading to the worse outcome of ovarian cancer patients treated with systemic chemotherapeutics.

MicroRNAs and Corresponding Targets in Esophageal Cancer as Shown In Vitro and In Vivo in Preclinical Models

Squamous cell carcinoma of the esophagus is associated with a dismal prognosis. Therefore, identification of new targets and implementation of new treatment modalities are issues of paramount importance. Based on a survey of the literature, we identified microRNAs conferring antitumoral activity in preclinical in vivo experiments. In the category of miRs targeting secreted factors and transmembrane receptors, four miRs were up-regulated and 10 were down-regulated compared with five out of nine in the category transcription factors, and six miRs were down-regulated in the category enzymes, including metabolic enzymes. The down-regulated miRs have targets which can be inhibited by small molecules or antibody-related entities, or re-expressed by reconstitution therapy. Up-regulated miRs have targets which can be reconstituted with small molecules or inhibited with antagomirs.

MicroRNA-based signatures impacting clinical course and biology of ovarian cancer: a miRNOmics study

Background

In Western countries, ovarian cancer (OC) still represents the leading cause of gynecological cancer-related deaths, despite the remarkable gains in therapeutical options. Novel biomarkers of early diagnosis, prognosis definition and prediction of treatment outcomes are of pivotal importance. Prior studies have shown the potentials of micro-ribonucleic acids (miRNAs) as biomarkers for OC and other cancers.

Methods

We focused on the prognostic and/or predictive potential of miRNAs in OC by conducting a comprehensive array profiling of miRNA expression levels in ovarian tissue samples from 17 non-neoplastic controls, and 60 tumor samples from OC patients treated at the Regina Elena National Cancer Institute (IRE). A set of 54 miRNAs with differential expression in tumor versus normal samples (T/N-deregulated) was identified in the IRE cohort and validated against data from the Cancer Genoma Atlas (TCGA) related to 563 OC patients and 8 non-neoplastic controls. The prognostic/predictive role of the selected 54 biomarkers was tested in reference to survival endpoints and platinum resistance (P-res).

Results

In the IRE cohort, downregulation of the 2 miRNA-signature including miR-99a-5p and miR-320a held a negative prognostic relevance, while upregulation of miR-224-5p was predictive of less favorable event free survival (EFS) and P-res. Data from the TCGA showed that downregulation of 5 miRNAs, i.e., miR-150, miR-30d, miR-342, miR-424, and miR-502, was associated with more favorable EFS and overall survival outcomes, while miR-200a upregulation was predictive of P-res. The 9 miRNAs globally identified were all included into a single biologic signature, which was tested in enrichment analysis using predicted/validated miRNA target genes, followed by network representation of the miRNA-mRNA interactions.

Conclusions

Specific dysregulated microRNA sets in tumor tissue showed predictive/prognostic value in OC, and resulted in a promising biological signature for this disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40364-021-00289-6.

DNA Based and Stimuli-Responsive Smart Nanocarrier for Diagnosis and Treatment of Cancer: Applications and Challenges

The rapid development of multidrug co-delivery and nano-medicines has made spontaneous progress in tumor treatment and diagnosis. DNA is a unique biological molecule that can be tailored and molded into various nanostructures. The addition of ligands or stimuli-responsive elements enables DNA nanostructures to mediate highly targeted drug delivery to the cancer cells. Smart DNA nanostructures, owing to their various shapes, sizes, geometry, sequences, and characteristics, have various modes of cellular internalization and final disposition. On the other hand, functionalized DNA nanocarriers have specific receptor-mediated uptake, and most of these ligand anchored nanostructures able to escape lysosomal degradation. DNA-based and stimuli responsive nano-carrier systems are the latest advancement in cancer targeting. The data exploration from various studies demonstrated that the DNA nanostructure and stimuli responsive drug delivery systems are perfect tools to overcome the problems existing in the cancer treatment including toxicity and compromised drug efficacy. In this light, the review summarized the insights about various types of DNA nanostructures and stimuli responsive nanocarrier systems applications for diagnosis and treatment of cancer.

Can microRNA become next-generation tools in molecular diagnostics and therapeutics? A systematic review

Background

MicroRNAs (miRNAs) represent a novel class of single-stranded RNA molecules of 18–22 nucleotides that serve as powerful tools in the regulation of gene expression. They are important regulatory molecules in several biological processes.

Main body

Alteration in the expression profiles of miRNAs have been found in several diseases. It is anticipated that miRNA expression profiling can become a novel diagnostic tool in the future.

Hence, this review evaluates the implications of miRNAs in various diseases and the recent advances in miRNA expression level detection and their target identification. A systematic approach to review existing literature available on databases such as Medline, PubMed, and EMBASE was conducted to have a better understanding of mechanisms mediating miRNA-dependent gene regulation and their role as diagnostic markers and therapeutic agents.

Conclusion

A clear understanding of the complex multilevel regulation of miRNA expression is a prerequisite to explicate the origin of a wide variety of diseases. It is understandable that miRNAs offer potential targets both in diagnostics and therapeutics of a multitude of diseases. The inclusion of specific miRNA expression profiles as biomarkers may lead to crucial advancements in facilitating disease diagnosis and classification, monitoring its prognosis, and treatment. However, standardization of methods has a pivotal role in the success of extensive use of miRNA expression profiling in routine clinical settings.

Long non-coding RNA DSCAM-AS1 upregulates USP47 expression through sponging miR-101-3p to accelerate osteosarcoma progression

Osteosarcoma (OS) originating from mesenchyme is one of the most common invasive tumors of bone, and has an extremely high mortality rate. Previous studies have reported that long non-coding RNAs (lncRNAs) play essential roles in the tumorigenesis and progression of a multitude of human cancers. The lncRNA DSCAM-AS1 has been reported to be an oncogenic gene in many cancers. However, the roles and regulatory mechanisms of DSCAM-AS1 in OS have not been deeply investigated. In this study, our findings prove that DSCAM-AS1 is highly expressed in OS cells. Knockdown of DSCAM-AS1 suppressed cell proliferation, migration, and invasiveness, and induced cell apoptosis in OS. Additionally, knockdown of DSCAM-AS1 inactivated the Wnt-β-catenin signaling pathway. Moreover, research into its molecular mechanisms confirmed that DSCAM-AS1 functions as a sponge for miR-101-3p, and that ubiquitin-specific peptidase 47 (USP47) is a target gene of miR-101-3p. Furthermore, a negative relationship between miR-101-3p and DSCAM-AS1 or USP47 was discovered. The results from our rescue assays suggest that DSCAM-AS1 regulates the progression of OS through binding with miR-101-3p to control the expression of USP47. Finally, we discovered that AKT-mTOR signaling pathway mediates the activity of DSCAM-AS1 in OS. Taken together, our results show that DSCAM-AS1 accelerates the progression of OS via the miR-101-3p-USP47 axis, which could present a new potential therapeutic treatment for OS.