microRNA-21 promotes breast cancer proliferation and metastasis by targeting LZTFL1

Long Non-coding RNA LINC00473 Promotes Breast Cancer Progression via miR-424-5p/CCNE1 Pathway

BACKGROUND

There has been a large increase in the incidence of breast cancer (BC) among women. LINC00473 is a cancer-related lncRNA, participating in the progression of many cancers, but its role in the progression of BC awaits more elaboration.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to quantify LINC00473, miR-424-5p, and cyclin E1 (CCNE1) mRNA expression levels in BC tissues and cells. Cell counting kit-8 (CCK-8) assay was employed to detect the cell viability; the cell migration and invasion abilities were evaluated by the Transwell assay. Western blot and immunohistochemistry (IHC) were adopted to study CCNE1 protein expression; dual-luciferase reporter assay was performed to clarify the targeting relationships among LINC00473, miR-424-5p, and CCNE1.

RESULTS

LINC00473 expression was elevated in BC tissues and cell lines, which was associated with lymph node metastasis and higher clinical stage of the patients with BC. LINC00473 proved to be a molecular sponge for miR-424-5p; LINC00473 knockdown impeded the growth, migration, invasion, and epithelial-mesenchymal transition of BC cells, while these effects were abolished by miR-424-5p inhibitors; miR-424-5p targeted CCNE1 to restrain its expression. LINC00473 positively regulated CCNE1 expression, and CCNE1 restoration counteracted the effects induced by LINC00473 knockdown in BC cells.

CONCLUSION

LINC00473 facilitates the progression of BC through miR-424-5p/CCNE1 axis.

Exosomal miRNAs as novel avenues for breast cancer treatment

Breast cancer is the most commonly diagnosed cancer and a leading cause of death in women worldwide. It is a heterogeneous disease, as shown by the gene expression profiles of breast cancer samples. It begins in milk-producing ducts, with a high degree of diversity between and within tumors, as well as among cancer-bearing individuals. The enhanced prevalence of breast cancer is influenced by various hormonal, lifestyle, and environmental factors, and very early onset of the disease correlates strongly with the risk of local and distant recurrence. Many subtypes are difficult to treat with conventional therapeutic modalities, and therefore, optimal management and early diagnosis are the first steps to minimizing the mortality linked with breast cancer. The use of newer methods of nanotechnology extends beyond the concept of synthesizing drug delivery mechanisms into the creation of new therapeutics, such as delivering chemotherapeutics with nanomaterial properties. Exosomes, a class of nanovesicles, are emerging as novel tools for deciphering the patient-specific proteins and biomarkers across different disease models, including breast cancer. In this review, we address the role of exosomal miRNA in breast cancer diagnosis and treatment.

MiRNAs Overexpression and Their Role in Breast Cancer: Implications for Cancer Therapeutics

MicroRNAs have a plethora of roles in various biological processes in the cells and most human cancers have been shown to be associated with dysregulation of the expression of miRNA genes. MiRNA biogenesis involves two alternative pathways, the canonical pathway which requires the successful cooperation of various proteins forming the miRNA-inducing silencing complex (miRISC), and the non-canonical pathway, such as the mirtrons, simtrons, or agotrons pathway, which bypasses and deviates from specific steps in the canonical pathway. Mature miRNAs are secreted from cells and circulated in the body bound to argonaute 2 (AGO2) and miRISC or transported in vesicles. These miRNAs may regulate their downstream target genes via positive or negative regulation through different molecular mechanisms. This review focuses on the role and mechanisms of miRNAs in different stages of breast cancer progression, including breast cancer stem cell formation, breast cancer initiation, invasion, and metastasis as well as angiogenesis. The design, chemical modifications, and therapeutic applications of synthetic anti-sense miRNA oligonucleotides and RNA mimics are also discussed in detail. The strategies for systemic delivery and local targeted delivery of the antisense miRNAs encompass the use of polymeric and liposomal nanoparticles, inorganic nanoparticles, extracellular vesicles, as well as viral vectors and viruslike particles (VLPs). Although several miRNAs have been identified as good candidates for the design of antisense and other synthetic modified oligonucleotides in targeting breast cancer, further efforts are still needed to study the most optimal delivery method in order to drive the research beyond preclinical studies.

Signature of miR-21 and MEG-2 and their correlation with TGF-β signaling in breast cancer

Breast cancer is highly prevalent and considered the main challenge to public health among females in Egypt as in other countries. MicroRNA-21 (miR-21) and MEG-2 are noncoding RNA attributed to their aberrant expression in several diseases, including breast cancer. This study aimed to assess the reliability of serum expression levels of miR-21 and MEG-2 in discriminating stages of breast cancer and scrutinize their correlations with the targeted transforming growth factor-beta (TGF-β) expression. One hundred and 30 participants whose ages ranged from 28 to 62 years were included in this study, divided into one hundred breast cancer patients and 30 healthy participants. miR-21 and TGF-β expression levels showed upregulation in patients with BC and elevated miR-21/TGF-β levels consistent with the BC stage. In addition, LncRNA (MEG-2) showed down-regulation in patients with BC. MEG-2 expression levels revealed a gradual decrease consistent with the BC stage. In addition, a negative relationship between the MEG-2 and the miR-21 and TGF-β differential expression was also noticed. This study suggested that miR-21 and MEG-2 can be used as prospective diagnostic biomarkers and emphasized the crucible role of TGF-β as therapeutic targets for BC.

The diagnostic significance of circulating miRNAs and metabolite profiling in early prediction of breast cancer in Egyptian women

Objective

Breast cancer (BC) is one of the most commonly diagnosed solid malignancies in women worldwide.

Purpose

Finding new non-invasive circulating diagnostic biomarkers will facilitate the early prediction of BC and provide valuable insight into disease progression and response to therapy using a safe and more accessible approach available every inspection time. Therefore, our present study aimed to investigate expression patterns of potentially circulating biomarkers that can differentiate well between benign, malignant, and healthy subjects.

Methods

To achieve our target, quantitative analyses were performed for some circulating biomarkers which have a role in the proliferation and tumor growth, as well as, glutamic acid, and human epidermal growth receptor 2 (HER2) in blood samples of BC patients in comparison to healthy controls using qRT-PCR, liquid chromatography/mass spectrometry (LC/MS/MS), and ELISA.

Results

Our findings showed that the two miRNAs (miRNA-145, miRNA-382) were expressed at lower levels in BC sera than healthy control group, while miRNA-21 was expressed at higher levels in BC patients than control subjects. Area under ROC curves of BC samples revealed that AUC of miRNA-145, miRNA-382, miRNA-21, and glutamic acid was evaluated to equal 0.99, 1.00, 1.00 and 1.00, respectively. Besides, there was a significantly positive correlation between miRNA-145 and miRNA-382 (r = 0.737), and a highly significant positive correlation between miRNA-21 and glutamic acid (r = 0.385).

Conclusion

Based on our results, we conclude that the detection of serum miRNA-145, -382 and -21 as a panel along with glutamic acid, and circulating HER2 concentrations could be useful as a non-invasive diagnostic profiling for early prediction of breast cancer in Egyptian patients. It can provide an insight into disease progression, discriminate between malignancy and healthy control, and overcome the use limitations (low sensitivity and specificity, repeated risky exposure, and high cost) of other detecting tools, including mammography, magnetic resonance imaging, and ultrasound.

MicroRNA 21as a novel biomarker in hepatitis C virus-related hepatocellular carcinoma

Background

Hepatocellular carcinoma is considered one of the most common cancers occurring in human population all over the world. It became an increasingly threatening malignancy due to both morbidity and mortality. Chronic viral hepatitis B and hepatitis C are two risk factors, which account for 80–90% of all HCC cases worldwide. Alfa Feto protien is used as a tumor marker for HCC diagnosis and prognosis prediction; however, its false negative rate when used alone is as high as 40% for patients with early-stage HCC. AFP levels remain normal in 15–30% of all the patients, even patients with advanced HCC. It has been demonstrated that miRNAs (MicroRNAs) are an important class of non-coding RNAs. They act as tumor oncogenes or suppressors and are involved in the HCC development. MiRNAs are endogenous nucleotides that can be found in intra- and extracellular spaces, such as the blood, urine, and saliva.

The study evaluated the miRNA 21 as a novel biomarker in patients with HCV related hepatocellular carcinoma.

Results

The study was conducted on three groups. Group (1) included 25 patients with liver cirrhosis due to hepatitis C virus infection. Group (2) included 25 patients with hepatocellular carcinoma (HCC) on top of liver cirrhosis due to hepatitis C virus infection. Group (3) included 10 normal control subjects. There was a significant difference in the mean level of miRNA between the three groups with p value < 0.001 with the highest value in group 2 ( 8.28 ± 2.55), then in group1 (5.04 ± 2.11) and the lowest in group 3 (control) (1.02 ± 0.07). MiRNA 21 has a sensitivity of 68% and a specificity of 96%, to differentiate between the liver cirrhosis group and HCC group.

Conclusion

miRNA 21 can be a promising marker for detection of patients with HCV-related hepatocellular carcinoma, with higher specificity compared to α feto protein; however, its cost is higher.

Circular Sponge against miR-21 Enhances the Antitumor Activity of Doxorubicin against Breast Cancer Cells

Breast cancer is the most common type of cancer in women, with chemotherapy being the main strategy. However, its effectiveness is reduced by drug resistance mechanisms. miR-21 is upregulated in breast cancer that has been linked to drug resistance and carcinogenic processes. Our aim was to capture miR-21 with a circular sponge (Circ-21) and thus inhibit the carcinogenic processes and drug resistance mechanisms in which it participates. Proliferation, migration, colony formation, cell cycle, and poly [ADP-ribose] polymerase 1 (PARP-1) and vascular endothelial growth factor (VEGF) detection assays were performed with MCF7 breast cancer cells and MCF10A non-tumor cells. In addition, doxorubicin resistance tests and detection of drug resistance gene expression were performed in MCF7 cells. Reduction in proliferation, as well as migration and colony formation, increased PARP-1 expression, inhibition of VEGF expression and cell cycle arrest in G2/M phase were displayed in the Circ-21 MCF7, which were not observed in the MCF10A cells. Furthermore, in the MCF7 cells, the Circ-21 enhanced the antitumor activity of doxorubicin and decreased the expression of resistance genes: ABCA1, ABCC4, and ABCC5. Based on these results, the use of Circ-21 can be considered a first step for the establishment of an effective gene therapy in the treatment of breast cancer.

Small Non-Coding RNAs in Human Cancer

Small non-coding RNAs are widespread in the biological world and have been extensively explored over the past decades. Their fundamental roles in human health and disease are increasingly appreciated. Furthermore, a growing number of studies have investigated the functions of small non-coding RNAs in cancer initiation and progression. In this review, we provide an overview of the biogenesis of small non-coding RNAs with a focus on microRNAs, PIWI-interacting RNAs, and a new class of tRNA-derived small RNAs. We discuss their biological functions in human cancer and highlight their clinical application as molecular biomarkers or therapeutic targets.

Circulating miRNA Expression Profiling in Breast Cancer Molecular Subtypes: Applying Machine Learning Analysis in Bioinformatics

BACKGROUND/AIM

Breast cancer is a leading worldwide cause of female cancer-related morbidity and mortality. Since molecular characteristics increasingly guide disease management, demystifying breast tumor miRNA signature emerges as an essential step toward personalized care. This study aimed to investigate the variations in circulating miRNA expression profiles between breast cancer subtypes and healthy controls and to identify relevant target genes and molecular functions.

MATERIALS AND METHODS

MiRNA expression was tested by miScript™ miRNA PCR Array Human Cancer Pathway Finder kit, and subsequently, a machine learning approach was applied for miRNA profiling of the various breast cancer molecular subtypes.

RESULTS

Serum samples from patients with primary breast cancer (n=66) and healthy controls (n=16) were analyzed. MiR-21 was the single common molecule among all breast cancer subtypes. Furthermore, several miRNAs were found to be differentially expressed explicitly in the different subtypes; luminal A (miR-23b, miR-142, miR-29a, miR-181d, miR-16, miR-29b, miR-155, miR-181c), luminal B (miR-148a, let-7d, miR-92a, miR-34c, let-7b, miR-15a), HER2+ (miR-125b, miR-134, miR-98, miR-143, miR-138, miR-135b) and triple negative breast cancer (miR-17, miR-150, miR-210, miR-372, let-7f, miR-191, miR-133b, miR-146b, miR-7). Finally, miRNA-associated target genes and molecular functions were identified.

CONCLUSION

Applying a machine learning approach to delineate miRNA signatures of various breast cancer molecular subtypes allows further understanding of molecular disease characteristics that can prove clinically relevant.

Cancer cells can be killed mechanically or with combinations of cytoskeletal inhibitors

For over two centuries, clinicians have hypothesized that cancer developed preferentially at the sites of repeated damage, indicating that cancer is basically “continued healing.” Tumor cells can develop over time into other more malignant types in different environments. Interestingly, indefinite growth correlates with the depletion of a modular, early rigidity sensor, whereas restoring these sensors in tumor cells blocks tumor growth on soft surfaces and metastases. Importantly, normal and tumor cells from many different tissues exhibit transformed growth without the early rigidity sensor. When sensors are restored in tumor cells by replenishing depleted mechanosensory proteins that are often cytoskeletal, cells revert to normal rigidity-dependent growth. Surprisingly, transformed growth cells are sensitive to mechanical stretching or ultrasound which will cause apoptosis of transformed growth cells (Mechanoptosis). Mechanoptosis is driven by calcium entry through mechanosensitive Piezo1 channels that activate a calcium-induced calpain response commonly found in tumor cells. Since tumor cells from many different tissues are in a transformed growth state that is, characterized by increased growth, an altered cytoskeleton and mechanoptosis, it is possible to inhibit growth of many different tumors by mechanical activity and potentially by cytoskeletal inhibitors.

Role of epigallocatechin-3- gallate in the regulation of known and novel microRNAs in breast carcinoma cells

Breast cancer comprises 30% of all cancer cases among the world’s women population. MicroRNAs are small, endogenous, non-coding RNAs that regulate cell proliferating and apoptotic pathways by modulating expressions of related genes. Phytochemicals like epigallocatechin-3-gallate (EGCG) are known to have a chemotherapeutic effect on cancer often through the regulation of microRNAs. The aim is to find out the key known and novel miRNAs, which are controlled by EGCG in breast cancer cell line MDA-MB-231. Next-generation sequencing (NGS) revealed 1,258 known and 330 novel miRNAs from untreated and 83 μM EGCG (IC50 value of EGCG) treated cells. EGCG modulated 873 known and 47 novel miRNAs in the control vs. treated sample. The hypothesis of EGCG being a great modulator of miRNAs that significantly control important cancer-causing pathways has been established by analyzing with Kyoto Encyclopedia of Genes and Genomes (KEGG) and Protein Analysis Through Evolutionary Relationships (PANTHER) database. Validation of known and novel miRNA expression differences in untreated vs. treated cells was done using qPCR. From this study, a few notable miRNAs were distinguished that can be used as diagnostics as well as prognostic markers for breast cancer.

The Novel Diagnostic Techniques and Biomarkers of Canine Mammary Tumors

Canine mammary tumors (CMTs) are considered a serious clinical problem in older bitches. Due to the high malignancy rate and poor prognosis, an early diagnosis is essential. This article is a summary of novel diagnostic techniques as well as the main biomarkers of CMTs. So far, CMTs are detected only when changes in mammary glands are clinically visible and surgical removal of the mass is the only recommended treatment. Proper diagnostics of CMT is especially important as they represent a very diverse group of tumors and therefore different treatment approaches may be required. Recently, new diagnostic options appeared, like a new cytological grading system of CMTs or B-mode ultrasound, the Doppler technique, contrast-enhanced ultrasound, and real-time elastography, which may be useful in pre-surgical evaluation. However, in order to detect malignancies before macroscopic changes are visible, evaluation of serum and tissue biomarkers should be considered. Among them, we distinguish markers of the cell cycle, proliferation, apoptosis, metastatic potential and prognosis, hormone receptors, inflammatory and more recent: metabolomic, gene expression, miRNA, and transcriptome sequencing markers. The use of a couple of the above-mentioned markers together seems to be the most useful for the early diagnosis of neoplastic diseases as well as to evaluate response to treatment, presence of tumor progression, or further prognosis. Molecular aspects of tumors seem to be crucial for proper understanding of tumorigenesis and the application of individual treatment options.

Exosomal non-coding RNAs have a significant effect on tumor metastasis

Exosomes are produced by the majority of eukaryotic cells and are capable of transporting a variety of substances, including non-coding RNAs, between cells. Metastasis is a significant cause of death from cancer. Numerous studies have established an important role for exosomal non-coding RNAs in tumor metastasis. Exosomal non-coding RNAs from a variety of cells have been shown to affect tumor metastasis via several mechanisms. Exosomes transmit non-coding RNAs between tumor cells, fibroblasts, endothelial cells, and immune cells within the tumor microenvironment. Exosomal non-coding RNAs also have an effect on epithelial-mesenchymal transition, angiogenesis, and lymphangiogenesis. Exosomes derived from tumor cells have the ability to transport non-coding RNAs to distant organs, thereby facilitating the formation of the metastatic niche. Due to their role in tumor metastasis, exosomal non-coding RNAs have the potential to serve as diagnostic or prognostic markers as well as therapeutic targets for tumors. The purpose of this paper is to review and discuss the mechanisms of exosomal non-coding RNAs, their role in tumor metastasis, and their clinical utility, aiming to establish new directions for tumor metastasis, diagnosis, and treatment research.

METTL3 m6A-dependently promotes miR-21-5p maturation to accelerate choriocarcinoma progression via the HIF1AN-induced inactivation of the HIF1A/VEGF pathway

BACKGROUND

Gestational choriocarcinoma is a highly malignant neoplastic disease derived from pathological changes in trophoblastic cells. Recent evidences have shown that N6-methyladenosine (m6A) modifications play important role in modulating the development of multiple cancers, but the detailed mechanisms by which m6A-mediated choriocarcinoma progression have not been fully delineated.

OBJECTIVES

This study aimed to investigate the role of m6A in choriocarcinoma and reveal its underlying molecular mechanisms.

METHODS

The expression of METTL3, miR-21-5p and HIF1AN was detected using RT-qPCR in tissues and cells. The protein expression of METTL3, HIF1AN, HIF1A and VEGF were measured by western blot. The luciferase reporter assays and RNA immunoprecipitation (RIP) were used to verify the relationship between miR-21-5p and HIF1AN. The CCK-8, colony formation and transwell assays were used to detected cell proliferation and cell migration, respectively.

RESULTS

Here, we demonstrated that the m6A methyltransferase-like 3 (METTL3) was aberrantly high-expressed in the clinical choriocarcinoma tissues and choriocarcinoma cell lines compared to the corresponding normal counterparts. The following functional experiments verified that silencing of METTL3 suppressed cell proliferation, migration, epithelial-mesenchymal transition (EMT) and tumorigenesis in vitro and in vivo to hamper the aggressiveness of choriocarcinoma. Next, the mechanical experiments confirmed that METTL3 promoted the maturation of miR-21-5p in an m6A-dependent manner, and elevated miR-21-5p subsequently degraded its downstream hypoxia-inducible factor asparagine hydroxylase (HIF1AN) by targeting its 3' untranslated regions (3'-UTR), resulting in the activation of the tumor-promoting HIF1A/VEGF pathway. Finally, the rescuing experiments verified that METTL3 ablation-induced inhibitory effects on the malignant phenotypes in choriocarcinoma were all abrogated by both miR-21-5p overexpression and HIF1AN downregulation.

CONCLUSIONS

Collectively, this study firstly reported the involvement of the METTL3/m6A/miR-21-5p/HIF1AN signaling cascade in regulating the progression of choriocarcinoma, which provided novel biomarkers for the diagnosis and treatment of this disease.

Downregulation of miR-21 as a promising strategy to overcome drug resistance in cancer

Despite tremendous achievements in the field of targeted cancer therapy, chemotherapy is still the main treatment option, which is challenged by acquired drug resistance. Various microRNAs are involved in developing drug-resistant cells. miR-21 is one of the first identified miRNAs involved in this process. Here, we conducted a literature review to categorize different mechanisms employed by miR-21 to drive drug resistance. miR-21 targets various genes involved in many pathways that can justify chemoresistance. It alters cancer cell metabolism and facilitates adaptation to the new environment. It also enhances drug detoxification in cancerous cells and increases genomic instability. We also summarized various strategies applied for the inhibition of miR-21 in order to reverse cancer drug resistance. These strategies include the delivery of antagomiRs, miRZip knockdown vectors, inhibitory small molecules, CRISPR-Cas9 technology, catalytic nucleic acids, artificial DNA and RNA sponges, and nanostructures like mesoporous silica nanoparticles, dendrimers, and exosomes. Furthermore, current challenges and limitations in targeting miR-21 are discussed in this article. Although huge progress has been made in the downregulation of miR-21 in drug-resistant cancer cells, there are still many challenges to be resolved. More research is still required to find the best strategy and timeline for the downregulation of miR-21 and also the most feasible approach for the delivery of this system into the tumor cells. In conclusion, downregulation of miR-21 would be a promising strategy to reverse chemoresistance, but still, more studies are required to clarify the aforementioned issues.

Potential utility of miRNAs for liquid biopsy in breast cancer

Breast cancer (BC) remains the most prevalent malignancy due to its incidence rate, recurrence, and metastasis in women. Conventional strategies of cancer detection– mammography and tissue biopsy lack the capacity to detect the complete cancer genomic landscape. Besides, they often give false- positive or negative results. The presence of this and other disadvantages such as invasiveness, high-cost, and side effects necessitates developing new strategies to overcome the BC burden. Liquid biopsy (LB) has been brought to the fore owing to its early detection, screening, prognosis, simplicity of the technique, and efficient monitoring. Remarkably, microRNAs (miRNAs)– gene expression regulators seem to play a major role as biomarkers detected in the samples of LB. Particularly, miR-21 and miR-155 among other possible candidates seem to serve as favorable biomarkers in the diagnosis and prognosis of BC. Hence, this review will assess the potential utility of miRNAs as biomarkers and will highlight certain promising candidates for the LB approach in the diagnosis and management of BC that may optimize the patient outcome.

Serum miRNA-204-5p as a potential non-invasive biomarker for the diagnosis of endometrial cancer with sentinel lymph node mapping

The lymph node status is one of the most critical prognostic factors used in determining adjuvant treatment in endometrial cancer (EC). Lymphadenectomy is associated significant surgical and postoperative risks. The use of sentinel lymph node mapping (SLNM) has emerged as an alternative method to complete lymphadenectomy in EC. However, there remains controversy surrounding the use of SLNM in high-risk disease and its false-negative rate (3%). The authors previously identified miR-204-5p as a tumor-suppressor miRNA associated with lymph node metastasis in EC tissues. The present study demonstrated that serum miR-204-5p in patients with EC has the potential for use as an early diagnostic biomarker combined with SLNM to assess the lymph node status prior to surgery. The present study also aimed to identify the optimal cut-off value of serum miR-204-5p. The relative expression levels of miR-204-5p were detected using reverse transcription-quantitative PCR in the serum of 52 patients with EC (total SLNM). A total of 20 patients diagnosed with ovarian cysts, 20 patients diagnosed with myoma, and 20 participants diagnosed with endometrial polyps or endometrial hyperplasia were included as the control group. miR-204-5p expression was also detected in lymph node tissues using in situ hybridization. The results revealed that serum miR-204-5p expression was downregulated in patients with EC compared with its expression in patients with benign ovarian cysts, myoma and endometrial hyperplasia/polyps (P<0.01). In accordance with the final pathological evaluation, patients with EC with a positive SLN status had a significantly lower level of miR-204-5p compared with those with a negative SLN status (P<0.01). The area under the ROC curve of miR-204-5p was 0.923, 95% CI (0.847-1.000), and the diagnostic value had a sensitivity of 87.2% and specificity of 80.0%, with an optimal cut-off value of 0.253. On the whole, it was demonstrated that a lower miR-204-5p expression is associated with lymph node metastasis in these SLN(+) EC tissues, indicating that the downregulation of serum miR-204-5p in patients with EC has potential for use as an early diagnostic biomarker combined with SLNM. In addition, with a cut-off value of 0.253, it appeared optimal for the prediction of lymph node metastasis in EC.

BPA Decreases PDCD4 in Bovine Granulosa Cells Independently of miR-21 Inhibition

microRNAs (miRNAs) are susceptible to environmental factors that might affect cellular function and impose negative effects on female reproduction. miR-21 is the most abundant miRNA in bovine granulosa cells and is widely reported as affected by Bisphenol A (BPA) exposure, yet the cause and consequences are not entirely elucidated. BPA is a synthetic endocrine disruptor associated with poor fertility. miR-21 function in bovine granulosa cells is investigated utilizing locked nucleic acid (LNA) oligonucleotides to suppress miR-21. Before measuring apoptosis and quantifying miR-21 apoptotic targets PDCD4 and PTEN, transfection was optimized and validated. BPA was introduced to see how it affects miR-21 regulation and which BPA-mediated effects are influenced by miR-21. miR-21 knockdown and specificity against additional miRNAs were confirmed. miR-21 was found to have antiapoptotic effects, which could be explained by its effect on the proapoptotic target PDCD4, but not PTEN. Previous findings of miR-21 overexpression were validated using BPA treatments, and the temporal influence of BPA on miR-21 levels was addressed. Finally, BPA effects on upstream regulators, such as VMP1 and STAT3, explain the BPA-dependent upregulation of miR-21 expression. Overall, this research enhances our understanding of miR-21 function in granulosa cells and the mechanisms of BPA-induced reproductive impairment.

Promising Biomarkers in Head and Neck Cancer: The Most Clinically Important miRNAs

Head and neck cancers (HNCs) comprise a heterogeneous group of tumors that extend from the oral cavity to the upper gastrointestinal tract. The principal etiologic factors for oral tumors include tobacco smoking and alcohol consumption, while human papillomavirus (HPV) infections have been accused of a high incidence of pharyngeal tumors. Accordingly, HPV detection has been extensively used to categorize carcinomas of the head and neck. The diverse nature of HNC highlights the necessity for novel, sensitive, and precise biomarkers for the prompt diagnosis of the disease, its successful monitoring, and the timely prognosis of patient clinical outcomes. In this context, the identification of certain microRNAs (miRNAs) and/or the detection of alterations in their expression patterns, in a variety of somatic fluids and tissues, could serve as valuable biomarkers for precision oncology. In the present review, we summarize some of the most frequently studied miRNAs (including miR-21, -375, -99, -34a, -200, -31, -125a/b, -196a/b, -9, -181a, -155, -146a, -23a, -16, -29, and let-7), their role as biomarkers, and their implication in HNC pathogenesis. Moreover, we designate the potential of given miRNAs and miRNA signatures as novel diagnostic and prognostic tools for successful patient stratification. Finally, we discuss the currently ongoing clinical trials that aim to identify the diagnostic, prognostic, or therapeutic utility of miRNAs in HNC.

Innovative targets of the lncRNA-miR-mRNA network in response to low-dose aspirin in breast cancer patients

This study aimed to investigate innovative targets in breast cancer patients by considering the interaction of the lncRNA-miR-mRNA network in response to low-dose aspirin. The candidate miRs were first taken from the GEO and TCGA databases. Then, the candidate network was constructed using the high-throughput sequencing data. The expression levels of candidate targets were finally measured using Real-Time PCR in luminal A breast cancer patients undergoing aspirin (80 mg daily for three months) and non-aspirin groups during chemotherapy after surgery. The expression levels of TGFβ, IL-17, IFNγ, and IL-β proteins were measured using the ELISA technique. 5 lncRNAs, 12 miRs, and 10 genes were obtained in the bioinformatic phase. A significant expression increase of the candidate tumor suppressor lncRNAs, miRs, and genes and a substantial expression decrease of the candidate onco-lncRNAs, oncomiRs, and oncogenes were achieved after the aspirin consumption. Unlike the non-aspirin group, the expression levels of TGFβ, IL-17, IFNγ, and IL-β proteins were significantly decreased following aspirin consumption. The Kaplan-Meier analysis indicated a longer overall survival rate in the patients after aspirin consumption. Our results showed that the lncRNA-miR-mRNA network might be a significant target for aspirin; their expression changes may be a new strategy with potential efficacy for cancer therapy or prevention.

MicroRNA-21 is immunosuppressive and pro-metastatic via separate mechanisms

MiR-21 was identified as a gene whose expression correlated with the extent of metastasis of murine mammary tumours. Since miR-21 is recognised as being associated with poor prognosis in cancer, we investigated its contribution to mammary tumour growth and metastasis in tumours with capacity for spontaneous metastasis. Unexpectedly, we found that suppression of miR-21 activity in highly metastatic tumours resulted in regression of primary tumour growth in immunocompetent mice but did not impede growth in immunocompromised mice. Analysis of the immune infiltrate of the primary tumours at the time when the tumours started to regress revealed an influx of both CD4⁺ and CD8⁺ activated T cells and a reduction in PD-L1⁺ infiltrating monocytes, providing an explanation for the observed tumour regression. Loss of anti-tumour immune suppression caused by decreased miR-21 activity was confirmed by transcriptomic analysis of primary tumours. This analysis also revealed reduced expression of genes associated with cell cycle progression upon loss of miR-21 activity. A second activity of miR-21 was the promotion of metastasis as shown by the loss of metastatic capacity of miR-21 knockdown tumours established in immunocompromised mice, despite no impact on primary tumour growth. A proteomic analysis of tumour cells with altered miR-21 activity revealed deregulation of proteins known to be associated with tumour progression. The development of therapies targeting miR-21, possibly via targeted delivery to tumour cells, could be an effective therapy to combat primary tumour growth and suppress the development of metastatic disease.

Analysis of the Role of Continuous Early Intervention in Improving the Quality of Life of Breast Cancer Patients

In order to improve the quality of life of breast cancer patients, this paper will apply continuous early intervention to the nursing of breast cancer patients. The continuous early intervention nursing model can propose countermeasures for the health problems faced by patients with postoperative chemotherapy. In order to analyze the effect of continuous early intervention nursing on negative emotions and quality of life in breast cancer patients, the effect of continuous early intervention in improving the quality of life of breast cancer patients is analyzed by means of experimental research. The control group is given routine nursing, and the observation group is given continuous early intervention nursing intervention. Moreover, this paper obtains data statistics in combination with statistical analysis. Through the comparison of the test results, it can be seen that the implementation of continuous early intervention nursing intervention in breast cancer patients can improve the nursing effect, effectively relieve the negative emotions of patients, and improve the quality of life of patients.

The Emerging Role of Non-Coding RNAs in Osteogenic Differentiation of Human Bone Marrow Mesenchymal Stem Cells

Autologous bone marrow-derived mesenchymal stem cells (BMSCs) are more easily available and frequently used for bone regeneration in clinics. Osteogenic differentiation of BMSCs involves complex regulatory networks affecting bone formation phenomena. Non-coding RNAs (ncRNAs) refer to RNAs that do not encode proteins, mainly including microRNAs, long non-coding RNAs, circular RNAs, piwi-interacting RNAs, transfer RNA-derived small RNAs, etc. Recent in vitro and in vivo studies had revealed the regulatory role of ncRNAs in osteogenic differentiation of BMSCs. NcRNAs had both stimulatory and inhibitory effects on osteogenic differentiation of BMSCs. During the physiological condition, osteo-stimulatory ncRNAs are upregulated and osteo-inhibitory ncRNAs are downregulated. The opposite effects might occur during bone degenerative disease conditions. Intracellular ncRNAs and ncRNAs from neighboring cells delivered via exosomes participate in the regulatory process of osteogenic differentiation of BMSCs. In this review, we summarize the recent advances in the regulatory role of ncRNAs on osteogenic differentiation of BMSCs during physiological and pathological conditions. We also discuss the prospects of the application of modulation of ncRNAs function in BMSCs to promote bone tissue regeneration in clinics.

Stochastic Collision Electrochemistry from Single Pt Nanoparticles: Electrocatalytic Amplification and MicroRNA Sensing

Single-particle collisions have made many achievements in basic research, but challenges still exist due to their low collision frequency and selectivity in complex samples. In this work, we developed an "on-off-on" strategy based on Pt nanoparticles (PtNPs) that catalyze N₂H₄ collision signals on the surface of carbon ultramicroelectrodes and established a new method for the detection of miRNA21 with high selectivity and sensitivity. PtNPs catalyze the reduction of N₂H₄ on the surface of carbon ultramicroelectrodes to generate a stepped collision signal, which is in the "on" state. The single-stranded DNA paired with miRNA21 is coupled with PtNPs to form the complex DNA/PtNPs. Because PtNPs are covered by DNA, the electrocatalytic collision of N₂H₄ oxidation is inhibited. At this time, the signal is in the "off" state. When miRNA21 is added, the strong complementary pairing between miRNA21 and DNA destroys the electrostatic adsorption of DNA/PtNP conjugates and restores the electrocatalytic performance of PtNPs, and the signal is in the "on" state again. Based on this, a new method for detecting miRNA21 was established. It provides a new way for small-molecule sensing and has a wide range of applications in electroanalysis, electrocatalysis, and biosensing.

Cytosolic microRNA-inducible nuclear translocation of Cas9 protein for disease-specific genome modification

MicroRNA-dependent mRNA decay plays an important role in gene silencing by facilitating posttranscriptional and translational repression. Inspired by this intrinsic nature of microRNA-mediated mRNA cleavage, here, we describe a microRNA-targeting mRNA as a switch platform called mRNA bridge mimetics to regulate the translocation of proteins. We applied the mRNA bridge mimetics platform to Cas9 protein to confer it the ability to translocate into the nucleus via cleavage of the nuclear export signal. This system performed programmed gene editing in vitro and in vivo. Combinatorial treatment with cisplatin and miR-21-EZH2 axis-targeting CRISPR Self Check-In improved sensitivity to chemotherapeutic drugs in vivo. Using the endogenous microRNA-mediated mRNA decay mechanism, our platform is able to remodel a cell's natural biology to allow the entry of precise drugs into the nucleus, devoid of non-specific translocation. The mRNA bridge mimetics strategy is promising for applications in which the reaction must be controlled via intracellular stimuli and modulates Cas9 proteins to ensure safe genome modification in diseased conditions.

A Crucial Angiogenesis-Associated Gene MEOX2 Could Be a Promising Biomarker Candidate for Breast Cancer

Background

Angiogenesis plays a critical role in the growth and metastasis of breast cancer and angiogenesis inhibition has become an effective strategy for cancer therapy. Our study aimed to clarify the key candidate genes and pathways related to breast cancer angiogenesis.

Methods

Differentially expressed genes (DEGs) in the raw breast cancer (BRCA) gene dataset from the Cancer Genome Atlas (TCGA) database were identified and gene ontology analysis of the DEGs was performed. Hub genes were subsequently determined using the Gene Expression Omnibus database. The expression of the mesenchyme homeobox 2 (MEOX2) in breast cancer cells and tissues was assessed by quantification real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC), respectively. The prognostic value of the MEOX2 gene in breast cancer tissue was evaluated with the Kaplan-Meier plotter.

Results

A total of 61 angiogenesis-related DEGs were identified in the TCGA dataset, among which the gene MEOX2 was significantly down-regulated. GO functional annotation and pathway enrichment analyses showed that MEOX2 was significantly enriched in the regulation of vasculature development. The IHC results confirmed that MEOX2 expression was repressed in breast cancer tissues and the relatively low level indicated the tissue was densely vascularized. Moreover, MEOX2 expression was significantly elevated in breast cancer cells after treatment with cisplatin (DDP) and epirubicin (EPI). Finally, the Kaplan-Meier plotter confirmed that higher expression levels of MEOX2 were related to better overall survival.

Conclusion

Our study revealed that the angiogenesis-associated gene MEOX2 can be used as a novel biomarker for breast cancer diagnosis and clinical therapy.

Context-Dependent Regulation of Gene Expression by Non-Canonical Small RNAs

In recent functional genomics studies, a large number of non-coding RNAs have been identified. It has become increasingly apparent that noncoding RNAs are crucial players in a wide range of cellular and physiological functions. They have been shown to modulate gene expression on different levels, including transcription, post-transcriptional processing, and translation. This review aims to highlight the diverse mechanisms of the regulation of gene expression by small noncoding RNAs in different conditions and different types of human cells. For this purpose, various cellular functions of microRNAs (miRNAs), circular RNAs (circRNAs), snoRNA-derived small RNAs (sdRNAs) and tRNA-derived fragments (tRFs) will be exemplified, with particular emphasis on the diversity of their occurrence and on the effects on gene expression in different stress conditions and diseased cell types. The synthesis and effect on gene expression of these noncoding RNAs varies in different cell types and may depend on environmental conditions such as different stresses. Moreover, noncoding RNAs play important roles in many diseases, including cancer, neurodegenerative disorders, and viral infections.

Non-Exosomal and Exosome-Derived miRNAs as Promising Biomarkers in Canine Mammary Cancer

Canine mammary cancer (CMC), similar to human breast cancer (HBC) in many aspects, is the most common neoplasm associated with significant mortality in female dogs. Due to the limited therapy options, biomarkers are highly desirable for early clinical diagnosis or cancer progression monitoring. Since the discovery of microRNAs (miRNAs or miRs) as post-transcriptional gene regulators, they have become attractive biomarkers in oncological research. Except for intracellular miRNAs and cell-free miRNAs, exosome-derived miRNAs (exomiRs) have drawn much attention in recent years as biomarkers for cancer detection. Analysis of exosomes represents a non-invasive, pain-free, time- and money-saving alternative to conventional tissue biopsy. The purpose of this review is to provide a summary of miRNAs that come from non-exosomal sources (canine mammary tumor, mammary tumor cell lines or canine blood serum) and from exosomes as promising biomarkers of CMC based on the current literature. As is discussed, some of the miRNAs postulated as diagnostic or prognostic biomarkers in CMC were also altered in HBC (such as miR-21, miR-29b, miR-141, miR-429, miR-200c, miR-497, miR-210, miR-96, miR-18a, miR19b, miR-20b, miR-93, miR-101, miR-105a, miR-130a, miR-200c, miR-340, miR-486), which may be considered as potential disease-specific biomarkers in both CMC and HBC.

Circ_SAR1A regulates the malignant behavior of lung cancer cells via the miR-21-5p/TXNIP axis

Background

Lung cancer is one of the most common malignancies globally and a significant component of cancer‐related deaths. The lack of early diagnosis accounts for detecting approximately 75% of cancer patients at an intermediate to an advanced stage, with a low 5‐year survival rate. Therefore, a more comprehensive understanding of the molecular mechanisms of lung cancer development is necessary to find reliable and effective therapeutic and diagnostic biomarkers.

Methods

circ_SAR1A, miR‐21‐5p, and TXNIP in lung cancer tissues, animal xenografts, and cell lines were validated by qRT‐PCR and western blotting analyses. RNase R digestion and nuclear/cytoplasm fractionation experiments were utilized to determine the stability and localization of circ_SAR1A in lung cancer cells. The binding between miR‐21‐5p and circ_SAR1A or TXNIP was confirmed by luciferase reporter, RNA pull‐down, Spearman's correlation, and rescue assays. CCK‐8, colony formation, flow cytometry, Transwell, and western blotting were utilized to illustrate the malignant behavior of lung cancer cells.

Results

circ_SAR1A and TXNIP were down‐regulated while miR‐21‐5p was up‐regulated in lung cancer samples and cells. circ_SAR1A was located predominantly in the cytoplasm; it inhibited lung cancer growth in vitro and in vivo by sponging to miR‐21‐5p. miR‐21‐5p silencing suppressed lung cancer malignancy by targeting TXNIP.

Conclusions

circ_SAR1A is a critical negative regulator of lung carcinogenesis. circ_SAR1A/miR‐21‐5p/TXNIP attenuation inhibited lung cancer progression, presenting an ideal diagnostic and a potential therapeutic target.

Exon-Intron Circular RNA circRNF217 Promotes Innate Immunity and Antibacterial Activity in Teleost Fish by Reducing miR-130-3p Function

Circular RNA (circRNA) is produced by splicing head to tail and is widely distributed in multicellular organisms, and circRNA reportedly can participate in various cell biological processes. In this study, we discovered a novel exon-intron circRNA derived from probable E3 ubiquitin-protein ligase RNF217 (RNF217) gene, namely, circRNF217, which was related to the antibacterial responses in teleost fish. Results indicated that circRNF217 played essential roles in host antibacterial immunity and inhibited the Vibrio anguillarum invasion into cells. Our study also found a microRNA miR-130-3p, which could inhibit antibacterial immune response and promote V. anguillarum invasion into cells by targeting NOD1. Moreover, we also found that the antibacterial effect inhibited by miR-130-3p could be reversed with circRNF217. In mechanism, our data revealed that circRNF217 was a competing endogenous RNA of NOD1 by sponging miR-130-3p, leading to activation of the NF-κB pathway and then enhancing the innate antibacterial responses. In addition, we also found that circRNF217 can promote the antiviral response caused by Siniperca chuatsi rhabdovirus through targeting NOD1. Our study provides new insights for understanding the impact of circRNA on host-pathogen interactions and formulating fish disease prevention to resist the severely harmful V. anguillarum infection.

Designing strategies of small-molecule compounds for modulating non-coding RNAs in cancer therapy

Non-coding RNAs (ncRNAs) have been defined as a class of RNA molecules transcribed from the genome but not encoding proteins, such as microRNAs, long non-coding RNAs, Circular RNAs, and Piwi-interacting RNAs. Accumulating evidence has recently been revealing that ncRNAs become potential druggable targets for regulation of several small-molecule compounds, based on their complex spatial structures and biological functions in cancer therapy. Thus, in this review, we focus on summarizing some new emerging designing strategies, such as high-throughput screening approach, small-molecule microarray approach, structure-based designing approach, phenotypic screening approach, fragment-based designing approach, and pharmacological validation approach. Based on the above-mentioned approaches, a series of representative small-molecule compounds, including Bisphenol-A, Mitoxantrone and Enoxacin have been demonstrated to modulate or selectively target ncRNAs in different types of human cancers. Collectively, these inspiring findings would provide a clue on developing more novel avenues for pharmacological modulations of ncRNAs with small-molecule drugs for future cancer therapeutics.

DNMT1 facilitates growth of breast cancer by inducing MEG3 hyper-methylation

Background

To understand the effect of DNMT1-mediated MEG3 promoter methylation on breast cancer progression.

Methods

Expression of DNMT1, MEG3 and miR-494-3p was assayed by qRT-PCR and western blot. Methylation-specific PCR was used to examine MEG3 promoter methylation level. ChIP, RNA binding protein immunoprecipitation assay and dual-luciferase reporter gene assay were applied to verify interaction between DNMT1 and MEG3, miR-494-3p and MEG3 and OTUD4. CCK-8, wound healing and Transwell assays were used to detect biological functions of breast cancer cells. Tumor growth was observed by tumor xenograft model.

Results

DNMT1 and miR-494-3p were highly expressed while MEG3 and OTUD4 were lowly expressed in breast cancer cells. Knockdown of DNMT1 inhibited progression of breast cancer cells by enhance MEG3 expression through demethylation. MEG3 could downregulate miR-494-3p expression, and OTUD4 was a target of miR-494-3p. Upregulation of MEG3 and downregulation of miR-494-3p both inhibited malignant behavior of cells in vitro. In addition, high MEG3 expression restrained growth of breast cancer in vivo.

Conclusion

Briefly, our results demonstrated that, DNMT1 induced methylation of MEG3 promoter, and played a key role in breast cancer growth throughmiR-494-3p/OTUD4 axis. These findings provide new insights into molecular therapeutic targets for breast cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02463-8.

MIMRDA: A Method Incorporating the miRNA and mRNA Expression Profiles for Predicting miRNA-Disease Associations to Identify Key miRNAs (microRNAs)

Identifying cancer-related miRNAs (or microRNAs) that precisely target mRNAs is important for diagnosis and treatment of cancer. Creating novel methods to identify candidate miRNAs becomes an imminent Frontier of researches in the field. One major obstacle lies in the integration of the state-of-the-art databases. Here, we introduce a novel method, MIMRDA, which incorporates the miRNA and mRNA expression profiles for predicting miRNA-disease associations to identify key miRNAs. As a proof-of-principle study, we use the MIMRDA method to analyze TCGA datasets of 20 types (BLCA, BRCA, CESE, CHOL, COAD, ESCA, HNSC, KICH, KIRC, KIRP, LIHC, LUAD, LUSC, PAAD, PRAD, READ, SKCM, STAD, THCA and UCEC) of cancer, which identified hundreds of top-ranked miRNAs. Some (as Category 1) of them are endorsed by public databases including TCGA, miRTarBase, miR2Disease, HMDD, MISIM, ncDR and mTD; others (as Category 2) are supported by literature evidences. miR-21 (representing Category 1) and miR-1258 (representing Category 2) display the excellent characteristics of biomarkers in multi-dimensional assessments focusing on the function similarity analysis, overall survival analysis, and anti-cancer drugs’ sensitivity or resistance analysis. We compare the performance of the MIMRDA method over the Limma and SPIA packages, and estimate the accuracy of the MIMRDA method in classifying top-ranked miRNAs via the Random Forest simulation test. Our results indicate the superiority and effectiveness of the MIMRDA method, and recommend some top-ranked key miRNAs be potential biomarkers that warrant experimental validations.

Effect of modified radical mastectomy combined with neo-adjuvant chemotherapy on postoperative recurrence rate, negative emotion, and life quality of patients with breast cancer

Breast cancer (BC) is mainly treated by surgery combined with chemotherapy, radiotherapy, and drugs comprehensively in clinical practice, and such a combined treatment can improve the survival rate of patients. This study was designed to determine the effect of modified radical mastectomy (MRM) combined with neo-adjuvant chemotherapy on patients with BC. Clinical data of 80 patients with BC were analyzed retrospectively. The patients were assigned to the control group (n=39) treated with MRM or the therapy group (n=41) treated with additional neo-adjuvant chemotherapy based on MRM. In this study, patients treated with MRM combined with neo-adjuvant chemotherapy experienced significantly shorter operation time and hospitalization time, less bleeding volume, and higher effective treatment rate than the control group. Moreover, the therapy group showed a significantly lower incidence of complications and higher life quality than the control group. Cox regression analysis showed that neo-adjuvant chemotherapy was an independent factor affecting the progression-free survival time of patients. This study has revealed the application value of MRM combined with neo-adjuvant chemotherapy in patients with BC.

lncRNA GAS8-AS1 regulates cancer cell proliferation and predicts poor survival of patients with gastric cancer

Long non-coding (lnc)RNAs have been recognized as important regulators in gastric cancer. lncRNA GAS8-AS1 is considered a tumor suppressor in multiple types of cancer, such as papillary thyroid carcinoma, ovarian cancer and colorectal cancer. However, the specific role of GAS8-AS1 in gastric cancer remains to be fully elucidated. The aim of the present study was to investigate the role of GAS8-AS1 in gastric cancer and its potential underlying mechanisms of action. The expression levels of GAS8-AS1, microRNA (miR)-21-3p, PTEN and pyruvate dehydrogenase (E1) alpha subunit gene (PDHA1) in gastric cancer and non-cancerous tissues, as well as in gastric cancer cell lines, were detected using reverse transcription-quantitative PCR. Cell proliferation was detected by using a Cell Counting Kit-8 assay. Cell migration and invasion were detected using a Transwell assay. Results of the present study demonstrated that the expression levels of GAS8-AS1 in gastric cancer tissues were significantly decreased, whereas its expression did not differ among cancer tissues at different clinical stages. Low expression levels of GAS8-AS1 predicted poor 5-year survival rates for 70 patients with gastric adenocarcinoma from the Affiliated Hospital of Xuzhou Medical University (Xuzhou, China) during patient follow-up. In addition, the expression levels of miR-21-3p were markedly increased in cancer tissues, and miR-21-3p expression was negatively associated with the expression of GAS8-AS1. The direct interaction between GAS8-AS1 and miR-21-3p was predicted using the starBase database and was confirmed by using an RNA pull-down assay. In gastric cell lines, the overexpression of GAS8-AS1 reduced the expression levels of mature miR-21-3p but did not affect the expression of miR-21-3p precursor, while the overexpression of miR-21-3p did not, in turn, affect the expression of GAS8-AS1. In addition, the overexpression of GAS8-AS1 inhibited cancer cell proliferation, while the overexpression of miR-21-3p promoted cancer cell proliferation and attenuated the effects of GAS8-AS1. Overexpression of miR-21-3p promoted cancer cell migration and invasion, whereas overexpression of GAS8-AS1 did not affect cell migration or invasion. In summary, results of the present study have demonstrated that GAS8-AS1 acts as a tumor suppressor in gastric cancer, and it may inhibit cancer cell proliferation by downregulating miR-21-3p.

Expression of the microRNA-30 family in pulmonary arterial hypertension and the role of microRNA-30d-5p in the regulation of pulmonary arterial smooth muscle cell toxicity and apoptosis

The biological processes of pulmonary artery vascular smooth muscle cells (PA-SMCs) and pulmonary artery endothelial cells in pulmonary arterial hypertension (PAH) are generally abnormal, with increased levels of proliferation and reduced levels of apoptosis. Although microRNAs (miRNAs/miRs) participate in a number of biological processes in a variety of diseases, such as tumors and infections, studies on the association between miRNAs and PAH are limited. In the present study, blood samples were collected from 6 patients with patent ductus arteriosus. The experimental group included 3 patients with severe PAH, while the control group included 3 patients without PAH. Microarray technology was used to detect the presence of any associated miRNAs. Moreover, a rat PAH model was established via left lung resection followed by monocrotaline injection, involving a total of 8 rats in the PAH group and 8 untreated rat in the control group. Reverse transcription-quantitative PCR was performed to verify the expression levels of the miR-30 family in the animal model. miR-30d-5p mimics and anti-miR-30d-5p were transfected into primary cultured PA-SMCs. Levels of cytotoxicity and cell apoptosis were examined, and Notch-3 expression levels were studied using western blotting. The results of the present study demonstrated that miR-30d-5p expression was downregulated in both patient blood and animal models of the PAH group compared with control groups. In primary cultured PA-SMCs, overexpression of miR-30d-5p attenuated the platelet-derived growth factor-induced toxicity of PA-SMCs, while knockdown of miR-30d-5p resulted in the increased toxicity of PA-SMCs compared with control group. The apoptosis rate of PA-SMCs increased with the overexpression of miR-30d-5p compared with control group. Moreover, the expression levels of Notch-3 in the miR-30d-5p group were significantly reduced compared with the anti-miR-30d-5p and miR-NC groups. In total, 10 circulating miRNAs that may be associated with PAH were discovered in the present study. Moreover, the expression of the miR-30 family was verified in animal models in vivo, and seven miRNAs in this family were discovered that may be associated with PAH. Additionally, miR-30d-5p was downregulated in both patients with PAH and animal models compared with control groups. Thus, the results of the present study demonstrated that the regulatory mechanism underlying PA-SMCs may be via the Notch-3 signaling pathway.

Identification of an mRNA isoform switch for HNRNPA1 in breast cancers

Roles of HNRNPA1 are beginning to emerge in cancers; however, mechanisms causing deregulation of HNRNPA1 function remain elusive. Here, we describe an isoform switch between the 3'-UTR isoforms of HNRNPA1 in breast cancers. We show that the dominantly expressed isoform in mammary tissue has a short half-life. In breast cancers, this isoform is downregulated in favor of a stable isoform. The stable isoform is expressed more in breast cancers, and more HNRNPA1 protein is synthesized from this isoform. High HNRNPA1 protein levels correlate with poor survival in patients. In support of this, silencing of HNRNPA1 causes a reversal in neoplastic phenotypes, including proliferation, clonogenic potential, migration, and invasion. In addition, silencing of HNRNPA1 results in the downregulation of microRNAs that map to intragenic regions. Among these miRNAs, miR-21 is known for its transcriptional upregulation in breast and numerous other cancers. Altogether, the cancer-specific isoform switch we describe here for HNRNPA1 emphasizes the need to study gene expression at the isoform level in cancers to identify novel cases of oncogene activation.

Highly sensitive microRNA detection by a duplex-specific nuclease amplification triggered three-dimensional DNA machine

MicroRNAs play important roles in disease diagnosis and therapy. However, current methods for microRNA detection suffer from low sensitivity and cannot directly detect short microRNAs. Herein, we have developed a highly sensitive and selective fluorescent method for direct microRNA detection by combining the duplex-specific nuclease-assisted recycling amplification and the nicking enzyme-powered three-dimensional DNA walker. Target microRNA initiates duplex-specific nuclease-assisted recycling amplification, releasing numerous bipedal walking strands. The released bipedal walking strands hybridize with carboxyfluorescein-labeled track DNA and form nicking recognition site. Driven by the hydrolysis of the nicking enzyme, the bipedal walking strand autonomously moves along the track strand, releasing a large number of carboxyfluorescein-labeled DNA fragments and generating obvious fluorescence signals. This dual-signal amplification method can directly detect microRNA 21 as low as 130 fM and has good selectivity. The proposed method is not only simple for nucleic acid design, but also can be used as a universal method for the highly sensitive detection of all RNAs.

Analysis of exosome-derived microRNAs reveals insights of intercellular communication during invasion of breast, prostate and glioblastoma cancer cells

MiRNAs represent a mechanism that regulates gene expression in many pathological conditions. Exosomes are known to be secreted from all types of cells, and the exosomes-released molecules are crucial messengers that can regulate cellular processes. We investigated the miRNAs content of exosomes released by cancer cells during the invasion . An invasion stimulus has been generated through scratches created on the confluent cells of cancer cell lines: glioblastoma, breast and prostate cancers.Several miRNAs were found to be significantly differentially abundant during the cell invasion , both in common among different cell lines and exclusive. Understanding the language codes among cells involved in invasion can lead to the development of therapies that can inhibit cellular communication, slowing or eventually stopping their activity.

Preclinical Imaging Evaluation of miRNAs' Delivery and Effects in Breast Cancer Mouse Models: A Systematic Review

BACKGROUND

We have conducted a systematic review focusing on the advancements in preclinical molecular imaging to study the delivery and therapeutic efficacy of miRNAs in mouse models of breast cancer.

METHODS

A systematic review of English articles published in peer-reviewed journals using PubMed, EMBASE, BIOSIS™ and Scopus was performed. Search terms included breast cancer, mouse, mice, microRNA(s) and miRNA(s).

RESULTS

From a total of 2073 records, our final data extraction was from 114 manuscripts. The most frequently used murine genetic background was Balb/C (46.7%). The most frequently used model was the IV metastatic model (46.8%), which was obtained via intravenous injection (68.9%) in the tail vein. Bioluminescence was the most used frequently used tool (64%), and was used as a surrogate for tumor growth for efficacy treatment or for the evaluation of tumorigenicity in miRNA-transfected cells (29.9%); for tracking, evaluation of engraftment and for response to therapy in metastatic models (50.6%).

CONCLUSIONS

This review provides a systematic and focused analysis of all the information available and related to the imaging protocols with which to test miRNA therapy in an in vivo mice model of breast cancer, and has the purpose of providing an important tool to suggest the best preclinical imaging protocol based on available evidence.

Hsa-miR-21-3p associates with breast cancer patient survival and targets genes in tumor suppressive pathways

Breast cancer is the cancer most often diagnosed in women. MicroRNAs (MIRs) are short RNA molecules that bind mRNA resulting in their downregulation. MIR21 has been shown to be an oncomiR in most cancer types, including breast cancer. Most of the effects of miR-21 have been attributed to hsa-miR-21-5p that is transcribed from the leading strand of MIR21, but hsa-miR-21-3p (miR-21-3p), transcribed from the lagging strand, is much less studied. The aim of the study is to analyze whether expression of miR-21-3p is prognostic for breast cancer. MiR-21-3p association with survival, clinical and pathological characteristics was analyzed in a large breast cancer cohort and validated in three separate cohorts, including TCGA and METABRIC. Analytical tools were also used to infer miR-21-3p function and to identify potential target genes and functional pathways. The results showed that in the exploration cohort, high miR-21-3p levels associated with shorter survival and lymph node positivity. In the three validation cohorts, high miR-21-3p levels associated with pathological characteristics that predict worse prognosis. Specifically, in the largest validation cohort, METABRIC (n = 1174), high miR-21-3p levels associated with large tumors, a high grade, lymph node and HER2 positivity, and shorter breast-cancer-specific survival (HR = 1.38, CI 1.13–1.68). This association remained significant after adjusting for confounding factors. The genes with expression levels that correlated with miR-21-3p were enriched in particular pathways, including the epithelial-to-mesenchymal transition and proliferation. Among the most significantly downregulated targets were MAT2A and the tumor suppressive genes STARD13 and ZNF132. The results from this study emphasize that both 3p- and 5p-arms from a MIR warrant independent study. The data show that miR-21-3p overexpression in breast tumors is a marker of worse breast cancer progression and it affects genes in pathways that drive breast cancer by down-regulating tumor suppressor genes. The results suggest miR-21-3p as a potential biomarker.

MicroRNAs Role in Breast Cancer: Theranostic Application in Saudi Arabia

Breast cancer is an aggressive silent disease, representing 11.7% of the diagnosed cancer worldwide, and it is also a leading cause of death in Saudi Arabia. Consequently, microRNAs have emerged recently as potential biomarkers to diagnose and monitor such cases at the molecular level, which tends to be problematic during diagnosis. MicroRNAs are highly conserved non- coding oligonucleotide RNA. Over the last two decades, studies have determined the functional significance of these small RNAs and their impact on cellular development and the interaction between microRNAs and messenger RNAs, which affect numerous molecular pathways and physiological functions. Moreover, many disorders, including breast cancer, are associated with the dysregulation of microRNA. Sparingly, many microRNAs can suppress cancer cell proliferation, apoptosis, angiogenesis, invasion, metastasis, and vice versa. Remarkably, microRNAs can be harvested from patients’ biofluids to predict disease progression that considered a non-invasive method. Nevertheless, MicroRNAs are currently utilized as anti- cancer therapies combined with other drug therapies or even as a single agents’ treatment. Therefore, this review will focus on microRNAs’ role in breast cancer as an indicator of disease progression. In addition, this review summarizes the current knowledge of drug sensitivity and methods in detecting microRNA and their application to improve patient care and identifies the current gaps in this field.

Targeting Engineered Nanoparticles for Breast Cancer Therapy

Breast cancer (BC) is the second most common cancer in women globally after lung cancer. Presently, the most important approach for BC treatment consists of surgery, followed by radiotherapy and chemotherapy. The latter therapeutic methods are often unsuccessful in the treatment of BC because of their various side effects and the damage incurred to healthy tissues and organs. Currently, numerous nanoparticles (NPs) have been identified and synthesized to selectively target BC cells without causing any impairments to the adjacent normal tissues or organs. Based on an exploratory study, this comprehensive review aims to provide information on engineered NPs and their payloads as promising tools in the treatment of BC. Therapeutic drugs or natural bioactive compounds generally incorporate engineered NPs of ideal sizes and shapes to enhance their solubility, circulatory half-life, and biodistribution, while reducing their side effects and immunogenicity. Furthermore, ligands such as peptides, antibodies, and nucleic acids on the surface of NPs precisely target BC cells. Studies on the synthesis of engineered NPs and their impact on BC were obtained from PubMed, Science Direct, and Google Scholar. This review provides insights on the importance of engineered NPs and their methodology for validation as a next-generation platform with preventive and therapeutic effects against BC.

Footprints of microRNAs in Cancer Biology

MicroRNAs (miRNAs) are short non-coding RNAs involved in post-transcriptional gene regulation. Over the past years, various studies have demonstrated the role of aberrant miRNA expression in the onset of cancer. The mechanisms by which miRNA exerts its cancer-promoting or inhibitory effects are apparent through the various cancer hallmarks, which include selective proliferative advantage, altered stress response, vascularization, invasion and metastasis, metabolic rewiring, the tumor microenvironment and immune modulation; therefore, this review aims to highlight the association between miRNAs and the various cancer hallmarks by dissecting the mechanisms of miRNA regulation in each hallmark separately. It is hoped that the information presented herein will provide further insights regarding the role of cancer and serve as a guideline to evaluate the potential of microRNAs to be utilized as biomarkers and therapeutic targets on a larger scale in cancer research.

MiR-106b-5p: A Master Regulator of Potential Biomarkers for Breast Cancer Aggressiveness and Prognosis

Breast cancer (BCa) is the leading cause of death by cancer in women worldwide. This disease is mainly stratified in four subtypes according to the presence of specific receptors, which is important for BCa aggressiveness, progression and prognosis. MicroRNAs (miRNAs) are small non-coding RNAs that have the capability to modulate several genes. Our aim was to identify a miRNA signature deregulated in preclinical and clinical BCa models for potential biomarker discovery that would be useful for BCa diagnosis and/or prognosis. We identified hsa-miR-21-5p and miR-106b-5p as up-regulated and hsa-miR-205-5p and miR-143-3p as down-regulated in BCa compared to normal breast or normal adjacent (NAT) tissues. We established 51 shared target genes between hsa-miR-21-5p and miR-106b-5p, which negatively correlated with the miRNA expression. Furthermore, we assessed the pathways in which these genes were involved and selected 12 that were associated with cancer and metabolism. Additionally, GAB1, GNG12, HBP1, MEF2A, PAFAH1B1, PPP1R3B, RPS6KA3 and SESN1 were downregulated in BCa compared to NAT. Interestingly, hsa-miR-106b-5p was up-regulated, while GAB1, GNG12, HBP1 and SESN1 were downregulated in aggressive subtypes. Finally, patients with high levels of hsa-miR-106b-5 and low levels of the abovementioned genes had worse relapse free survival and worse overall survival, except for GAB1.

Breast Cancer Classification Prediction Based on Ultrasonic Image Feature Recognition

Exploring an effective method to manage the complex breast cancer clinical information and selecting a suitable classifier for predictive modeling still require continuous research and verification in the actual clinical environment. This paper combines the ultrasound image feature algorithm to construct a breast cancer classification model. Furthermore, it combines the motion process of the ultrasound probe to accurately connect the ultrasound probe to the breast tumor. Moreover, this paper constructs a hardware and software system structure through machine vision algorithms and intelligent motion algorithms. Furthermore, it combines coordinate transformation and image recognition algorithms to expand the recognition process to realize automatic and intelligent real-time breast cancer diagnosis. In addition, this paper combines machine learning algorithms to process data and obtain an intelligent system model. Finally, this paper designs experiments to verify the intelligent system of this paper. Through experimental research, it can be seen that the breast cancer classification prediction system based on ultrasonic image feature recognition has certain effects.

MiR-192-5p inhibits proliferation, migration, and invasion in papillary thyroid carcinoma cells by regulation of SH3RF3

Background: The decreased level of miR-192-5p has been reported in several kinds of cancers, including bladder, colon, ovarian, and non-small cell lung cancer. However, the expression and function of miR-192-5p in papillary thyroid carcinoma/cancer (PTC) remains unknown.

Objective: The present study aimed to explore the function and underlying mechanism of miR-192-5p in PTC development.

Methods: PTC tissues and relative normal controls from PTC patients were collected. qRT-PCR analysis was performed to measure miR-192-5p and SH3RF3 mRNA level in PTC tissues and cell lines. CCK-8 method and FCM assay were used to test cell proliferation and apoptosis in TPC-1 cells, respectively. The abilities of cell migration and invasion were detected by wound healing and transwell assays, respectively. The protein expression was evaluated by Western blot. The interaction between miR-192-5p and Src homology 3 (SH3) domain containing ring finger 3 (SH3RF3) were confirmed by dual-luciferase reporter assay.

Results: MiR-192-5p level was obviously decreased in PTC tissues and cell lines. Overexpression of miR-192-5p suppressed proliferation, migration, invasion, and EMT process, while induced apoptosis in TPC-1 cells. In addition, miR-192-5p negatively modulated SH3RF3 expression by binding to its 3′-untranslated region (3′UTR). Silencing SH3RF3 inhibited the migration, invasion, and EMT of TPC-1 cells. In the meantime, matrine, an alkaloid extracted from herb, exerted its anti-cancer effects in PTC cells dependent on increase in miR-192-5p expression and decrease in SH3RF3 expression.

Conclusion: We firstly declared that miR-192-5p played a tumor suppressive role in PTC via targeting SH3RF3. Moreover, matrine exerted its anti-cancer effects in PTC via regulating miR-192-5p/SH3RF3 pathway.