miR‐4458 regulates cell proliferation and apoptosis through targeting SOCS1 in triple‐negative breast cancer

Nectin-4 has emerged as a compelling target for breast cancer

The incidence of breast cancer in women has increased year by year, becoming one of the most common malignant tumors in females worldwide. Most patients can be treated with surgery and endocrine drugs, but there are still some patients who lack effective treatment, such as triple-negative breast cancer (TNBC). Nectin-4, a protein encoded by poliovirus receptor-associated protein 4, is a Ca2+-independent immunoglobulin-like protein. It is mainly involved in the adhesion between cells. In recent years, studies have found that Nectin-4 is overexpressed in breast cancer and several other malignancies. Otherwise, several monoclonal antibodies and inhibitors targeting Nectin-4 have shown prosperous outcomes, so Nectin-4 has great potential to be a therapeutic target for breast cancer. The present review systematically describes the significance of Nectin-4 in each aspect of breast cancer, as well as the molecular mechanisms of these aspects mediated by Nectin-4. We further highlight ongoing or proposed therapeutic strategies for breast cancer specific to Nectin-4.

Organotypic 3D Cell-Architecture Impacts the Expression Pattern of miRNAs-mRNAs Network in Breast Cancer SKBR3 Cells

BACKGROUND

Currently, most of the research on breast cancer has been carried out in conventional two-dimensional (2D) cell cultures due to its practical benefits, however, the three-dimensional (3D) cell culture is becoming the model of choice in cancer research because it allows cell-cell and cell-extracellular matrix (ECM) interactions, mimicking the native microenvironment of tumors in vivo.

METHODS

In this work, we evaluated the effect of 3D cell organization on the expression pattern of miRNAs (by Small-RNAseq) and mRNAs (by microarrays) in the breast cancer SKBR3 cell line and analyzed the biological processes and signaling pathways regulated by the differentially expressed protein-coding genes (DE-mRNAs) and miRNAs (DE-microRNAs) found in the organoids.

RESULTS

We obtained well-defined cell-aggregated organoids with a grape cluster-like morphology with a size up to 9.2 × 105 μm3. The transcriptomic assays showed that cell growth in organoids significantly affected (all p < 0.01) the gene expression patterns of both miRNAs, and mRNAs, finding 20 upregulated and 19 downregulated DE-microRNAs, as well as 49 upregulated and 123 downregulated DE-mRNAs. In silico analysis showed that a subset of 11 upregulated DE-microRNAs target 70 downregulated DE-mRNAs. These genes are involved in 150 gene ontology (GO) biological processes such as regulation of cell morphogenesis, regulation of cell shape, regulation of canonical Wnt signaling pathway, morphogenesis of epithelium, regulation of cytoskeleton organization, as well as in the MAPK and AGE-RAGE signaling KEGG-pathways. Interestingly, hsa-mir-122-5p (Fold Change (FC) = 15.4), hsa-mir-369-3p (FC = 11.4), and hsa-mir-10b-5p (FC = 20.1) regulated up to 81% of the 70 downregulated DE-mRNAs.

CONCLUSION

The organotypic 3D cell-organization architecture of breast cancer SKBR3 cells impacts the expression pattern of the miRNAs-mRNAs network mainly through overexpression of hsa-mir-122-5p, hsa-mir-369-3p, and hsa-mir-10b-5p. All these findings suggest that the interaction between cell-cell and cell-ECM as well as the change in the culture architecture impacts gene expression, and, therefore, support the pertinence of migrating breast cancer research from conventional cultures to 3D models.

ER Negative Breast Cancer and miRNA: There Is More to Decipher Than What the Pathologist Can See!

Breast cancer (BC), the most prevalent cancer in women, is a heterogenous disease. Despite advancements in BC diagnosis, prognosis, and therapeutics, survival rates have drastically decreased in the metastatic setting. Therefore, BC still remains a medical challenge. The evolution of high-throughput technology has highlighted gaps in the classification system of BCs. Of particular interest is the notorious triple negative BC, which was recounted as being heterogenous itself and it overlaps with distinct subtypes, namely molecular apocrine (MA) and luminal androgen (LAR) BCs. These subtypes are, even today, still misdiagnosed and poorly treated. As such, researchers and clinicians have been looking for ways through which to refine BC classification in order to properly understand the initiation, development, progression, and the responses to the treatment of BCs. One tool is biomarkers and, specifically, microRNA (miRNA), which are highly reported as associated with BC carcinogenesis. In this review, the diverse roles of miRNA in estrogen receptor negative (ER-) and androgen receptor positive (AR+) BC are depicted. While highlighting their oncogenic and tumor suppressor functions in tumor progression, we will discuss their diagnostic, prognostic, and predictive biomarker potentials, as well as their drug sensitivity/resistance activity. The association of several miRNAs in the KEGG-reported pathways that are related to ER-BC carcinogenesis is presented. The identification and verification of accurate miRNA panels is a cornerstone for tackling BC classification setbacks, as is also the deciphering of the carcinogenesis regulators of ER - AR + BC.

Circular RNA circHMCU promotes breast tumorigenesis through miR-4458/PGK1 regulatory cascade

BACKGROUND

Circular RNAs (circRNAs) are abnormally expressed in breast cancer (BC). However, the biological function and mechanism of circHMCU still need to be further explored.

METHODS

The expression levels of circHMCU, miR-4458 and phosphoglycerate kinase 1 (PGK1) were measured by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. The glucose uptake, lactate production and ATP level were assayed by related commercial kits. Cell Counting Kit-8 (CCK8), 5'-ethynyl-2'-deoxyuridine (EdU) and flow cytometry assays were used to test cell proliferation and apoptosis, respectively. The migratory and invasive abilities were detected by transwell and wound-healing assays. The relationships among circHMCU, miR-4458 and PGK1 were verified by dual-luciferase reporter assay. The function of circHMCU in tumor growth was evaluated by animal studies.

RESULTS

CircHMCU was upregulated in BC tissues and cell lines, whereas miR-4458 was downregulated. For biological experiments, circHMCU knockdown inhibited cell proliferation, migration, glycolysis, while promoted cell apoptosis. CircHMCU bound miR-4458, and miR-4458 targeted PGK1. MiR-4458 inhibition reversed circHMCM knockdown-mediated effects on BC cell malignant behaviors. MiR-4458 overexpression suppressed cell glycolysis, proliferation, and metastasis and promoted apoptosis in BC cells through PGK1 upregulation. Additionally, circHMCU suppressed tumor growth in vivo.

CONCLUSION

CircHMCU acted as an oncogenic factor by regulating the miR-4458/PGK1 axis in BC.

MiR-4458-loaded gelatin nanospheres target COL11A1 for DDR2/SRC signaling pathway inactivation to suppress the progression of estrogen receptor-positive breast cancer

RNA interference is a promising way to treat cancer and the construction of a stable drug delivery system is critically important for its application. Gelatin nanospheres (GNs) comprise a biodegradable drug vehicle with excellent biocompatibility, but there are limited studies on its delivery and role in the stabilization of miRNA and siRNA. Breast cancer is the most diagnosed type of female cancer worldwide. Abnormal miRNA expression is closely related to the occurrence and progression of estrogen receptor-positive (ER+) breast cancer. In this study, miR-4458 was upregulated in ER+ breast cancer and could inhibit MCF-7 cell viability, colony formation, migration, and invasion. Collagen type XI alpha 1 (COL11A1) was identified as a directly interacting protein of miR-4458 and an important component of the extracellular matrix. High COL11A1 expression was positively correlated with poor prognosis, lower overall survival, disease-free survival, and a late tumor-node-metastasis stage. COL11A1 knockdown could inhibit MCF-7 cell migration and invasion. GNs were used to load a miR-4458 mimic or COL11A1 siRNA (si-COL11A1) to achieve sustained and controlled release in xenograft nude mice. Their tumor volume was decreased, tumor cell apoptosis was promoted, and hepatic metastasis was significantly inhibited. Moreover, the DDR2/SRC signaling pathway was inactivated after transfection with the miR-4458 mimic and si-COL11A1. In conclusion, GNs can be potentially used to deliver siRNA or miRNA, and miR-4458 and COL11A1 can be possible targets for ER+ breast cancer treatment.

The functional significance and cross-talk of non-coding RNAs in triple negative and quadruple negative breast cancer

One of the leading causes of cancer-related deaths worldwide is breast cancer, among which triple-negative breast cancer (TNBC) is the most malignant and lethal subtype. This cancer accounts for 10-20% of all breast cancer deaths. Proliferation, tumorigenesis, and prognosis of TNBC are affected when the androgen receptor (AR) is not expressed, and it is classified as quadruple negative breast cancer (QNBC). Non-coding RNAs, such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), play a significant role in tumorigenesis by virtue of their oncogenic and tumor-suppressive properties. To regulate tumorigenesis, miRNAs interact with their target mRNAs and modulate their expression, whereas lncRNAs can either act alone or interact with miRNAs or other molecules through various signaling pathways. Conversely, circRNAs regulate tumorigenesis by acting as miRNA sponges predominantly. Recently, non-coding RNAs were studied comprehensively for their roles in tumor proliferation, progression, and metastasis. As a result of existing studies and research progress, non-coding RNAs have been implicated in TNBC, necessitating their use as biomarkers for future diagnostic applications. In this review, the non-coding RNAs are explicitly implicated in the regulation of breast cancer, and their cross-talk between TNBC and QNBC is also discussed.

Transcriptomic Signatures of End-Stage Human Dilated Cardiomyopathy Hearts with and without Left Ventricular Assist Device Support

Left ventricular assist device (LVAD) use in patients with dilated cardiomyopathy (DCM) can lead to a differential response in the LV and right ventricle (RV), and RV failure remains the most common complication post-LVAD insertion. We assessed transcriptomic signatures in end-stage DCM, and evaluated changes in gene expression (mRNA) and regulation (microRNA/miRNA) following LVAD. LV and RV free-wall tissues were collected from end-stage DCM hearts with (n = 8) and without LVAD (n = 8). Non-failing control tissues were collected from donated hearts (n = 6). Gene expression (for mRNAs/miRNAs) was determined using microarrays. Our results demonstrate that immune response, oxygen homeostasis, and cellular physiological processes were the most enriched pathways among differentially expressed genes in both ventricles of end-stage DCM hearts. LV genes involved in circadian rhythm, muscle contraction, cellular hypertrophy, and extracellular matrix (ECM) remodelling were differentially expressed. In the RV, genes related to the apelin signalling pathway were affected. Following LVAD use, immune response genes improved in both ventricles; oxygen homeostasis and ECM remodelling genes improved in the LV and, four miRNAs normalized. We conclude that LVAD reduced the expression and induced additional transcriptomic changes of various mRNAs and miRNAs as an integral component of the reverse ventricular remodelling in a chamber-specific manner.

Contribution of miRNAs in the Pathogenesis of Breast Cancer

Breast cancer is the most frequently diagnosed cancer among females. Gene expression profiling methods have shown the deregulation of several genes in breast cancer samples and have confirmed the heterogeneous nature of breast cancer at the genomic level. microRNAs (miRNAs) are among the recently appreciated contributors in breast carcinogenic processes. These small-sized transcripts have been shown to partake in breast carcinogenesis through modulation of apoptosis, autophagy, and epithelial-mesenchymal transition. Moreover, they can confer resistance to chemotherapy. Based on the contribution of miRNAs in almost all fundamental aspects of breast carcinogenesis, therapeutic intervention with their expression might affect the course of this disorder. Moreover, the presence of miRNAs in the peripheral blood of patients potentiates these transcripts as tools for non-invasive diagnosis of breast cancer.

Comprehensive analysis of ubiquitin-proteasome system genes related to prognosis and immunosuppression in head and neck squamous cell carcinoma

The ubiquitin-proteasome system (UPS) with a capacity of degrading multiple intracellular proteins is an essential regulator in tumor immunosurveillance. Tumor cells that escape from recognition and destruction of immune system have been consistently characterized an important hallmark in the setting of tumor progression. Little know about the exact functions of UPS-related genes (UPSGs) and their relationships with antitumor immunity in head and neck squamous cell carcinoma (HNSCC) patients. In this study, for the first time, we comprehensively identified 114 differentially expressed UPSGs (DEUPSGs) and constructed a prognostic risk model based on the eight DEUPSGs (BRCA1, OSTM1, PCGF2, PSMD2, SOCS1, UCHL1, UHRF1, and USP54) in the TCGA-HNSCC database. This risk model was validated using multiple data sets (all P < 0.05). The high-risk score was found to be an independently prognostic factor in HNSCC patients and was significantly correlated with T cells suppression. Accordingly, our risk model can act as a prognostic signature and provide a novel concept for improving the precise immunotherapy for patients with HNSCC.

MicroRNA and cyclooxygenase-2 in breast cancer

Cancer remains a major public health problem worldwide and the latest statistics show that breast cancer (BC) is among the most frequent in women. MicroRNAs (miRNAs; miRs) and cyclooxygenase-2 (COX-2) are new diagnostic and therapeutic biomarkers for monitoring BC. COX-2 is a prominent tumor-associated inflammatory factor highly expressed in human tumor cells, including BC. Expression of COX-2 contributes to tumor growth, metastasis and recurrence. MiRs are a group of short (~22 nucleotides), noncoding regulatory RNAs that downregulate gene expression post-transcriptionally and play vital roles in regulating cancer development and progression. Interestingly, there are a group of miRNAs differentially expressed in breast tumor tissue. Understanding the pathway linking miRNAs to COX-2 can provide novel insight for suppressing COX-2 expression via gene silencing thereby leading to the development of selective miRNA inhibitors. Further research can also reveal key intermediate players and their potential as therapeutic targets. Given the association between different miRNAs and COX-2 expression in BC, this review presents a comprehensive overview of the current literature concerning how miRNAs and COX-2 signaling interact in BC progression.

Circ_0001667 knockdown blocks cancer progression and attenuates adriamycin resistance by depleting NCOA3 via releasing miR-4458 in breast cancer

Accumulating evidence suggests that developmental chemoresistance in cancers is closely associated with the dysregulation of circular RNA transcriptions. The objective of this study is to disclose the role of circ_0001667 and provide a potential functional mechanism in breast cancer. Quantitative real-time PCR was applied for the analysis of circ_0001667, microRNA-4458 (miR-4458) and nuclear receptor coactivator 3 (NCOA3) expression. In adriamycin (ADM)-resistant cell lines, we investigated cell proliferation using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay and colony formation assay. Cell migration and cell invasion were determined by transwell assay. The protein levels of multi-drug resistance-1, matrix metalloproteinases-9, cleaved-caspase3, cleaved-caspase9 and NCOA3 were detected by western blot. ADM resistance was ascertained by IC50 value using MTT assay. Cell apoptosis was checked by flow cytometry assay. The putative relationship between miR-4458 and circ_0001667 and NCOA3 was validated by pull-down assay, dual-luciferase reporter assay or RNA Immunoprecipitation assay. Circ_0001667 knockdown inhibited MCF-7/ADM and MDA-MB-231/ADM cell proliferation, migration, invasion and ADM resistance. MiR-4458 was a target of circ_0001667, and its expression was decreased in ADM-resistant tumor tissues and cells. MiR-4458 inhibition reversed the effects of circ_0001667 knockdown. In depth, NCOA3 was a target of circ_0001667, and circ_0001667 knockdown weakened NCOA3 expression by releasing miR-4458. MCF-7/ADM and MDA-MB-231/ADM cell proliferation, migration, invasion, and ADM resistance inhibited by miR-4458 restoration were recovered by NCOA3 overexpression. Circ_0001667 knockdown also repressed tumor growth and ADM resistance in vivo. Circ_0001667 knockdown blocks cancer progression and attenuates ADM resistance by depleting NCOA3 via releasing miR-4458 in breast cancer.

Circular RNA circ_0000337 contributes to osteosarcoma via the miR-4458/BACH1 pathway

BACKGROUND

As the most prevalent primary bone malignancy in children and adolescents, osteosarcoma (OS) has attracted increasing attention. The role of circRNAs in OS has been elucidated in some reports, but many circRNAs remain unexplored. Circ_0000337 has only been revealed as an oncogenic circRNA in esophageal squamous cell carcinoma. Yet whether circ_0000337 exerts any specific function in OS has not been unmasked.

METHODS

RT-qPCR was used for measurement of circ_0000337, miR-4458 and BACH1 mRNA levels. Western blot was conducted to detect BACH1 protein. CCK-8 assay, Casepase-3 activity assay and transwell assay were utilized to assess changes on cellular processes. Cytoplasmic/nuclear fractionation assay was conducted for circ_0000337 localization in OS cells. Luciferase reporter assay and RIP assay were performed to validate the interaction between miR-4458 and circ_0000337 or BACH1.

RESULTS

Circ_0000337 expression was upregulated in OS cell lines and it silence hindered OS cell proliferation and migration. MiR-4458 was downregulated in OS cells and miR-4458 upregulation suppressed OS cell growth and migration. Importantly, circ_0000337 sponged miR-4458 to elevate BACH1 expression, thus facilitating OS development.

CONCLUSIONS

This research for the first time documented that circ_0000337 promoted OS progression via sponging miR-4458 and thus elevating BACH1 expression, offering rational therapeutic target for OS.

The Anticancer Effects of Flavonoids through miRNAs Modulations in Triple-Negative Breast Cancer

Triple- negative breast cancer (TNBC) incidence rate has regularly risen over the last decades and is expected to increase in the future. Finding novel treatment options with minimum or no toxicity is of great importance in treating or preventing TNBC. Flavonoids are new attractive molecules that might fulfill this promising therapeutic option. Flavonoids have shown many biological activities, including antioxidant, anti-inflammatory, and anticancer effects. In addition to their anticancer effects by arresting the cell cycle, inducing apoptosis, and suppressing cancer cell proliferation, flavonoids can modulate non-coding microRNAs (miRNAs) function. Several preclinical and epidemiological studies indicate the possible therapeutic potential of these compounds. Flavonoids display a unique ability to change miRNAs' levels via different mechanisms, either by suppressing oncogenic miRNAs or activating oncosuppressor miRNAs or affecting transcriptional, epigenetic miRNA processing in TNBC. Flavonoids are not only involved in the regulation of miRNA-mediated cancer initiation, growth, proliferation, differentiation, invasion, metastasis, and epithelial-to-mesenchymal transition (EMT), but also control miRNAs-mediated biological processes that significantly impact TNBC, such as cell cycle, immune system, mitochondrial dysregulation, modulating signaling pathways, inflammation, and angiogenesis. In this review, we highlighted the role of miRNAs in TNBC cancer progression and the effect of flavonoids on miRNA regulation, emphasizing their anticipated role in the prevention and treatment of TNBC.

LINC00665 promotes the progression of acute myeloid leukemia by regulating the miR-4458/DOCK1 pathway

This study aimed to explore the role of LINC00665, miR-4458 and DOCK1 and their interactions in the development of acute myeloid leukemia (AML). The relative expression of LINC00665, miR-4458 and DOCK1 in AML samples was measured using qRT-PCR, and the protein level of DOCK1 in AML cell lines was examined using western blot. CCK8, BrdU, transwell, cell adhesion, and caspase-3 activity assays were carried out to evaluate the viability, proliferation, migration, adhesion, and apoptosis of AML cells, respectively. Luciferase reporter, RIP, and RNA pull-down assays were also performed to confirm the target relationship among LINC00665, miR-4458 and DOCK1. Findings revealed that LINC00665 and DOCK1 were aberrantly overexpressed in AML tissues and that the expression of miR-4458 was low in AML tissues. Silencing LINC00665 or DOCK1 presented significant restriction to the proliferation, migration and adhesion of AML cells. Apart from that, it was found that inhibiting miR-4458 could enhance the proliferation, migration and adhesion of AML cells but suppress the apoptosis of AML cells. Experimental results also indicated that LINC00665 exerted its positive function on AML cells by sponging miR-4458 and that miR-4458 influenced the progression of AML cells by targeting DOCK1 directly. Overall, this finding not only provided a novel molecular pathway for the diagnosis and treatment of AML but also showed that LINC00665 could enhance the progression of AML by regulating the miR-4458/DOCK1 pathway.

Circulating microRNAs and their role in the immune response in triple-negative breast cancer

Breast cancer (BC) is the most common type of cancer in women worldwide, and despite advances in treatments, its incidence and mortality are increasing. Therefore, it is necessary to develop new, non-invasive tests that provide more accurate diagnosis and prognosis in a timely manner. A promising approach is measuring the presence of biomarkers to detect tumors at various stages and determine their specific characteristics, thus allowing for more personalized treatment. MicroRNAs (miRNAs) serve a role in gene expression, primarily by interacting with messenger RNAs, and may be potential biomarkers for detecting cancer. They are detectable in tissues and blood, including plasma and/or serum, are stable and often tumor specific. Also, different miRNAs are associated with specific BC molecular subtypes. Triple-negative BC (TNBC) is a type of BC in which the primary targets for hormonal therapy are absent. It is an aggressive phenotype, which frequently metastasizes and is associated with an unfavorable prognosis. The present review focuses on circulating miRNAs in patients with TNBC, with an emphasis on their interaction with the immune response checkpoint genes PD-1, PD-L1 and CTLA4. Modulation and response of the immune system are of interest in cancer treatment due to the success of immunotherapy in the treatment of various neoplasms. Based on the findings of this literature review and the in silico analysis performed as part of this review, it is concluded that circulating hsa-miR-195 and hsa-miR-155 in TNBC interact with checkpoint genes involved in the immune response. Further analysis of the expression of these circulating miRNAs and their association with prognosis in patients with TNBC treated with immunotherapy should be assessed to evaluate their possible use as non-invasive predictive biomarkers. In addition, functional studies to analyze biologically relevant targets in the development and prognosis of TNBC, which could be therapeutic targets, are also recommended.

Circular RNA PRMT5 confers cisplatin-resistance via miR-4458/REV3L axis in non-small-cell lung cancer

Multifactor and multistep processes were elucidated to participate in the progression of non-small-cell lung cancer (NSCLC). Circular RNA 0031250 (circ-PRMT5) was a vital factor in NSCLC. However, the role of circ-PRMT5 in cisplatin (DDP)-resistance needed to be further highlighted. Expression profiles of circ-PRMT5, microRNA (miR)-4458, and EV3-like DNA-directed polymerase ζ catalytic subunit (REV3L) were detected using quantitative real-time polymerase chain reaction. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, flow cytometry, and transwell assays were performed to determine the half-maximal inhibitory concentration of DDP, cell viability, apoptosis, and invasion in vitro. Besides, the protein levels of REV3L and indicated proteins were examined by adopting western blot. Dual-luciferase reporter assay was performed to analyze the interaction between miR-4458 and circ-PRMT5 or REV3L. The functional role of circ-PRMT5 was explored using a xenograft tumor model. Levels of circ-PRMT5 and REV3L were markedly increased, while miR-4458 was downregulated in resistant tissues and cells. Knockdown of circ-PRMT5 enhanced cell apoptosis, DDP-sensitivity, and declined metastasis in NSCLC with DDP resistance. Besides, miR-4458 inhibition or REV3L upregulation could revert circ-PRMT5 absence-mediated effect on DDP-sensitivity in vitro. Mechanically, circ-PRMT5 was a sponge of miR-4458 to regulate REV3L. Importantly, circ-PRMT5 silencing could interact with DDP treatment expedite the decrease of tumor growth in vivo. Circ-PRMT5 promoted DDP resistance via REV3L by sponging miR-4458 in NSCLC, thus providing a novel therapeutic strategy for patients with NSCLC.

Potential miRNAs for miRNA-Based Therapeutics in Breast Cancer

MicroRNAs (miRNAs) are small non-coding RNAs that can post-transcriptionally regulate the genes involved in critical cellular processes. The aberrant expressions of oncogenic or tumor suppressor miRNAs have been associated with cancer progression and malignancies. This resulted in the dysregulation of signaling pathways involved in cell proliferation, apoptosis and survival, metastasis, cancer recurrence and chemoresistance. In this review, we will first (i) provide an overview of the miRNA biogenesis pathways, and in vitro and in vivo models for research, (ii) summarize the most recent findings on the roles of microRNAs (miRNAs) that could potentially be used for miRNA-based therapy in the treatment of breast cancer and (iii) discuss the various therapeutic applications.

miR-4458 inhibits the epithelial-mesenchymal transition of hepatocellular carcinoma cells by suppressing the TGF-β signaling pathway via targeting TGFBR1

Hepatocellular carcinoma (HCC) is one of the most lethal cancers in the world. MicroRNAs play a pivotal role in the progression of various cancers. To date, very little attention has been paid to miR-4458. Therefore, the aim of our study was to explore the function and underlying molecular mechanism of miR-4458 in HCC. We found that the expression of miR-4458 was reduced in HCC tissues and cell lines. Forced overexpression of miR-4458 inhibited the migration, invasion, and epithelial-mesenchymal transition (EMT) of HCC cells, while downregulation of miR-4458 promoted the aggressive phenotype. Furthermore, transforming growth factor beta receptor 1 (TGFBR1), the modulator of the TGF-β signaling pathway, was verified to be a novel target gene of miR-4458 by dual-luciferase reporter gene assay. Upregulated miR-4458 dramatically abolished TGFBR1 and p-Smad2/3 expression, thus blocking the TGF-β signaling pathway. Moreover, restoration of TGFBR1 partially rescued the miR-4458-mediated suppressive effect on the migration, invasion, and EMT and reactivated the TGF-β signaling pathway in HCC cells. In summary, our findings first demonstrated a mechanism of miR-4458 in HCC cell migration, invasion, and EMT by regulating the TGF-β signaling pathway via directly targeting TGFBR1.

NRF1-enhanced miR-4458 alleviates cardiac hypertrophy through releasing TTP-inhibited TFAM

Growing evidence suggests the crucial role of microRNAs (miRNAs) in regulating basic cell functions, and therefore participating in the pathologic development of diverse human diseases, including cardiac hypertrophy. Herein, we explained that miR-4458 was distinctly stimulated in Ang II-stimulated hypertrophic H9c2 cells. Intriguingly, miR-4458 inhibition led to exacerbated hypertrophic phenotypes in Ang II-treated H9c2 cells. In addition, the compensatory upregulation of miR-4458 in Ang II-treated H9c2 cells was ascribed to its transcriptional enhancement by NRF1, a transcription factor previously identified to be activated in early cardiac hypertrophy. Moreover, we discovered that miR-4458 served as a negative modulator in cardiac hypertrophy by prompting TFAM, a well-recognized myocardial protective protein. TTP, a RBP that always leads to degradation of recognized mRNAs, was predicted to interact with both miR-4458 and TFAM mRNA. Importantly, we verified that miR-4458 facilitated TFAM expression in cardiomyocytes by directly targeting TTP and releasing TTP-destabilized TFAM mRNA. On the whole, these findings demonstrated that NRF1-induced miR-4458 boosted TFAM via targeting TTP to dampen the exacerbation of cardiac hypertrophy, which indicates miR-4458 as a promising biomarker for the cardiac hypertrophy treatment.

MicroRNAs Involved in Carcinogenesis, Prognosis, Therapeutic Resistance and Applications in Human Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is the most aggressive, prevalent, and distinct subtype of breast cancer characterized by high recurrence rates and poor clinical prognosis, devoid of both predictive markers and potential therapeutic targets. MicroRNAs (miRNA/miR) are a family of small, endogenous, non-coding, single-stranded regulatory RNAs that bind to the 3′-untranslated region (3′-UTR) complementary sequences and downregulate the translation of target mRNAs as post-transcriptional regulators. Dysregulation miRNAs are involved in broad spectrum cellular processes of TNBC, exerting their function as oncogenes or tumor suppressors depending on their cellular target involved in tumor initiation, promotion, malignant conversion, and metastasis. In this review, we emphasize on masses of miRNAs that act as oncogenes or tumor suppressors involved in epithelial–mesenchymal transition (EMT), maintenance of stemness, tumor invasion and metastasis, cell proliferation, and apoptosis. We also discuss miRNAs as the targets or as the regulators of dysregulation epigenetic modulation in the carcinogenesis process of TNBC. Furthermore, we show that miRNAs used as potential classification, prognostic, chemotherapy and radiotherapy resistance markers in TNBC. Finally, we present the perspective on miRNA therapeutics with mimics or antagonists, and focus on the challenges of miRNA therapy. This study offers an insight into the role of miRNA in pathology progression of TNBC.

Triple-Input Molecular AND Logic Gates for Sensitive Detection of Multiple miRNAs

Abnormal miRNA expressions are closely related to the occurrence and development of cancers. It is of great significance to monitor miRNA expression levels for early diagnosis and therapy of the diseases. This study presents two independent colorimetric strategies for simultaneously monitoring multiple miRNAs based on cross-linking or non-cross-linking aggregations of gold nanoparticles (AuNPs). By introducing a Y shaped DNA structure and two types of DNA modified AuNPs, a triple-input DNA AND logic gate is facilely developed with the cross-linking aggregation of AuNPs as the signal output. To improve the sensitivity and shorten reaction time, the logic gate is modified by further employing a three DNA strands formed duplex and hybridization chain reaction. Non-cross-linking aggregation of AuNPs is used to evaluate the concentration of initial miRNA inputs. This strategy does not require DNA modification of AuNPs and ultrahigh sensitivity is achieved with the amplification of hybridization chain reaction. The present work may provide powerful tools for multiple miRNAs diagnostics and inspire further development of DNA based logic gates.

Identification of dysregulated serum miR-508-3p and miR-885-5p as potential diagnostic biomarkers of clear cell renal carcinoma

Clear cell renal cell carcinoma (ccRCC), the most common subtype, accounts for approximately 80% of all RCC cases. ccRCC patients typically present with an advanced stage at the time of diagnosis resulting in a poor patient prognosis. The present study aimed to identify novel potential microRNAs (miRNAs or miRs) in peripheral blood as biomarkers for the detection of ccRCC. Candidate miRNAs were selected through integrated analysis of the Gene Expression Omnibus (GEO) database, The Cancer Genome Atlas (TCGA) database, and from clinical samples. The expression levels of miRNAs were quantified using reverse transcription‑quantitative PCR. Receiver operating characteristic (ROC) curve analysis was used to explore the diagnostic values of the miRNAs. Bioinformatic analysis of candidate miRNAs was conducted by using the STRING database. After an integrated analysis of the GEO and TCGA databases, four miRNAs were found to be consistently dysregulated in ccRCC tissues. Then, their expression levels in serum and diagnostic utilities were further explored. We discovered that serum miR‑508‑3p and miR‑885‑5p were significantly dysregulated in ccRCC patients with marked diagnostic values. The area under the ROC curve (AUC) of serum miR‑508‑3p and miR‑885‑5p was 0.80 (95% CI, 0.73‑0.87) and 0.87 (95% CI, 0.79‑0.95), respectively. Functional enrichment analysis revealed that both miR‑508‑3p and miR‑885‑5p were closely associated with cellular metabolic processes. In conclusion, serum miR‑508‑3p and miR‑885‑5p are novel potential biomarkers for the diagnosis of ccRCC.

MicroRNAs and Epigenetics Strategies to Reverse Breast Cancer

Breast cancer is a sporadic disease with genetic and epigenetic components. Genomic instability in breast cancer leads to mutations, copy number variations, and genetic rearrangements, while epigenetic remodeling involves alteration by DNA methylation, histone modification and microRNAs (miRNAs) of gene expression profiles. The accrued scientific findings strongly suggest epigenetic dysregulation in breast cancer pathogenesis though genomic instability is central to breast cancer hallmarks. Being reversible and plastic, epigenetic processes appear more amenable toward therapeutic intervention than the more unidirectional genetic alterations. In this review, we discuss the epigenetic reprogramming associated with breast cancer such as shuffling of DNA methylation, histone acetylation, histone methylation, and miRNAs expression profiles. As part of this, we illustrate how epigenetic instability orchestrates the attainment of cancer hallmarks which stimulate the neoplastic transformation-tumorigenesis-malignancy cascades. As reversibility of epigenetic controls is a promising feature to optimize for devising novel therapeutic approaches, we also focus on the strategies for restoring the epistate that favor improved disease outcome and therapeutic intervention.