MicroRNA miR-21 overexpression in human breast cancer is associated with advanced clinical stage, lymph node metastasis and patient poor prognosis

Exosome biomarkers in breast cancer: Systematic review and meta-analysis

BACKGROUND

Breast cancer (BC) has become the primary cancer that threatens women's health and life expectancy. Early diagnosis is crucial for effective treatment and favourable prognosis. As a non-invasive and valuable liquid biopsy method, exosomes are promising for the diagnosis and prognosis of BC. The aim of this meta-analysis is to evaluate the diagnostic and prognostic value of exosome biomarkers in BC.

METHODS

A systematic search of relevant English literature was conducted in PubMed, Web of Science, and Cochrane library until August 2024 (diagnosis) and October 2024 (prognosis). QUADAS-2 and QUAPAS were used to assess the quality of the literature. Summary statistics and analyses of relevant effect sizes were conducted using STATA software. Subgroup analysis and sensitivity analysis were performed to identify potential sources of heterogeneity.

RESULTS

For diagnosis, a total of 31 articles with 3,778 patients and 2,722 controls were included, the pooled sensitivity (SEN), specificity (SPE), and area under the receiver operating characteristic curve (AUC) of overall exosome biomarkers were 0.89 (95 %CI: 0.86-0.91), 0.87 (95 %CI: 0.85-0.90), and 0.94 (95 %CI: 0.92-0.96), respectively, indicating a high diagnostic value of exosomes in BC patients. Subgroup analysis suggested that miRNAs in exosomes exhibited better diagnostic value compared to proteins and non-miRNAs, the SEN, SPE, and AUC were 0.89 (95 %CI: 0.82-0.93), 0.86 (95 %CI: 0.80-0.90), and 0.92 (95 %CI: 0.90-0.94), respectively. Among all miRNAs, the pooled SEN, SPE, and AUC of miR-21 were 0.86 (95 %CI: 0.67-0.95), 0.90 (95 %CI: 0.78-0.96), and 0.95 (95 %CI: 0.92-0.96), respectively. The diagnostic efficiency was improved when biomarkers were combined as a panel (SEN 0.91 versus 0.87, SPE 0.89 versus 0.86, AUC 0.96 versus 0.91). In terms of prognosis, we retrieved 14 articles with 2,781 patients. The pooled HR of overall survival (OS) and progression-free survival (PFS) were 1.41 (95 %CI: 0.92-1.90) and 4.39 (95 %CI: 1.87-6.91), respectively, indicating exosome biomarkers like soluble HLA-G, miR-1246, miR-155, and PSMA were a predictor of poor PFS in BC patients. Subgroup analysis in OS group revealed a significant association between the overexpression of exosome proteins (soluble HLA-G, AnxA2, NGF, CXCL13) and worse OS in BC patients (HR = 2.91, 95 %CI: 1.36-4.47). Similarly, the overexpression of miR-1246 and miR-155 was associated with worse PFS in BC patients (HR = 4.13, 95 %CI: 1.24-7.03). Moreover, when biomarkers were combined as a panel, the prognostic efficiency significantly improved in OS (HR = 4.05, 95 %CI: 2.26-5.84) outcome.

CONCLUSION

The meta-analysis revealed that exosome miR-21 might serve as a promising diagnostic biomarker in BC. Dysregulated exosome proteins and miRNAs could predict poor OS and PFS outcomes, respectively.

Autophagy as a potential therapeutic target in regulating improper cellular proliferation

Autophagy is a degradative process that makes rapid turnover of old and impaired proteins and organelles possible. It is highly instigated by stress signals, like starvation, and contributes to the cell's homeostasis. Autophagy performs a crucial function in keeping cell genomic integrity stable. Impaired autophagic flux is implicated in neurodegenerative diseases, abnormal ageing, and cancerous diseases. In diseases like cancer, autophagy performs a dualistic function; it can have both a tumor-suppressive and supportive role. Autophagy in the initial phases of tumorigenesis maintains the integrity of the genome and, if it fails, leads to cell death, thus having a tumor-suppressive role. Meanwhile, autophagy also imparts the function of the pro-survival mechanism in the latter stages of tumorigenesis and supports the cancerous cells in surviving conditions like hypoxia and increased oxidative stress. Autophagy also helps cancerous cells develop drug resistance in some cases. Thus, modulation of the autophagic mechanism is a possible therapeutic strategy in cancer therapy as its inhibition can sensitise cancer cells to anti-cancerous drugs. The promotion of autophagy, in some cases, can also safeguard cells from toxic protein aggregation and enhanced oxidative stress. Excessive autophagy can result in autophagic cell death. Autophagy also regulates several cellular processes and cell death pathways, like apoptosis. Therefore, an in-depth knowledge of the autophagy process and its regulating molecules is critically important. Pharmaceutical small molecules or cellular target modulation can help modulate the cellular autophagy process in the context of specific disease conditions.

Binary light-up fluorescent probe based on silver nanoclusters for MicroRNA detection

Silver nanoclusters (Ag NCs) are widely applied in the biosensing of metal ions, small organic molecules, nucleic acids, amino acids, and proteins due to their particular fluorescence and chemical properties. Organic matrices such as DNA are usually employed for Ag NC synthesis and stabilization. They make Ag NC/matrix complexes biocompatible and sensitive to the environment. It has recently been shown that Ag NCs based on DNA matrices are capable of self-assembly and rearrangement followed by a change in the fluorescence and absorbance characteristics. These attributes allow the development of sensors with target molecule detection visible even by the naked eye. Here we suggest a simple one-step turn-on highly specific microRNA-210 sensor based on a fluorescent Ag NC. The main feature of the sensor is the smart design of a binary matrix, which provides the appearance of a bright green fluorescence signal only after Ag NCs/DNA-matrix complexes are bonded to the target sequence. The microRNA detection assay requires no additional action because the process proceeds by itself. A comprehensive optimization of the binary probe structure and location was carried out. An approach to detection leading to minimal background signal was defined as follows. The approach involves the preliminary synthesis of non-fluorescent silver clusters using a single strand of the binary matrix containing a 5'-CCCGTTTT-3' part. It was shown that these "dark" structures can be stored for at least a month before analysis. The fluorescence intensity of the green Ag NCs increases in the presence of the microRNA-210 sequence, and that dependence on the target concentration tends to be linear in the range of 5-500 nM. The sensor demonstrates specificity to the miR-210 sequence, and the LOD (limit of detection) was established as 5 nM in serum samples.

Exosomal miRNA-based theranostics in cervical cancer: bridging diagnostics and therapy

Cervical cancer (CC) remains a significant global health burden, particularly in low- and middle-income countries, where access to effective screening and treatment is limited. Despite advancements in conventional therapies, such as surgery, chemotherapy, and radiotherapy, challenges related to late-stage diagnosis, treatment resistance, and disease recurrence persist. The emergence of microRNAs (miRNAs) as key regulators of gene expression has revolutionized cancer diagnostics and therapeutics. Exosomal miRNAs, in particular, have garnered attention due to their stability, detectability in bodily fluids, and pivotal roles in tumor progression, metastasis, and immune modulation. This review provides a comprehensive overview of the role of exosomal miRNAs in the theranostic landscape of CC. We explore their involvement in disease pathogenesis, highlighting their potential as minimally invasive diagnostic biomarkers for early detection and disease monitoring. Furthermore, we examine their utility in therapeutic strategies, including miRNA-mediated drug delivery systems and miRNA-targeted interventions to overcome chemoresistance. Integrating exosomal miRNA profiling with current diagnostic modalities could enhance screening sensitivity and specificity, while miRNA-based therapies offer novel avenues to improve treatment efficacy. This review discusses recent advancements in miRNA research, current challenges in clinical translation, and future perspectives on leveraging exosomal miRNAs for personalized CC care.

Integration of MicroRNAs with nanomedicine: tumor targeting and therapeutic approaches

MicroRNAs (miRNAs) are small, non-coding RNA molecules that play a pivotal role in the post-transcriptional regulation of gene expression. Over the past decade, they have emerged as key regulators in cancer progression, influencing different cellular processes such as proliferation, apoptosis, metastasis, and immune evasion. Their unique ability to target multiple genes simultaneously makes miRNAs highly attractive as potential therapeutic agents in oncology. However, several challenges have hindered their direct clinical application, most notably their inherent instability in biological fluids, rapid degradation by nucleases, and inefficient delivery to specific tumor sites. Additionally, off-target effects and the potential for toxicity further complicate the therapeutic use of miRNAs. Nanomedicine offers a promising solution to these challenges by enabling the development of advanced platforms for the stable, safe, and targeted delivery of miRNAs. Nanoparticle-based delivery systems, such as liposomes, polymeric nanoparticles, and inorganic nanocarriers, can protect miRNAs from degradation, improve their bioavailability, and allow for precise tumor targeting through passive or active targeting mechanisms. These nanocarriers can also be engineered to release miRNAs in response to specific stimuli within the tumor microenvironment, enhancing therapeutic efficacy while minimizing side effects. This review will explore the integration of miRNAs with nanotechnology, focusing on various nanoparticle formulations and their roles in enhancing miRNA stability, specificity, and function in cancer treatment. In addition, we will discuss current advances in preclinical and clinical applications, highlight promising tumor-targeting strategies, and address the remaining challenges such as toxicity, immunogenicity, and scalability. Future research should focus on overcoming these barriers, ultimately paving the way for the widespread adoption of personalized miRNA-based nanomedicine in cancer therapy.

Non-coding RNAs, a double-edged sword in breast cancer prognosis

Cancer is a rising issue worldwide, and numerous studies have focused on understanding the underlying reasons for its occurrence and finding proper ways to defeat it. By applying technological advances, researchers are continuously uncovering and updating treatments in cancer therapy. Their vast functions in the regulation of cell growth and proliferation and their significant role in the progression of diseases, including cancer. This review provides a comprehensive analysis of ncRNAs in breast cancer, focusing on long non-coding RNAs such as HOTAIR, MALAT1, and NEAT1, as well as microRNAs such as miR-21, miR-221/222, and miR-155. These ncRNAs are pivotal in regulating cell proliferation, metastasis, drug resistance, and apoptosis. Additionally, we discuss experimental approaches that are useful for studying them and highlight the advantages and challenges of each method. We then explain the results of these clinical trials and offer insights for future studies by discussing major existing gaps. On the basis of an extensive number of studies, this review provides valuable insights into the potential of ncRNAs in cancer therapy. Key findings show that even though the functions of ncRNAs are vast and undeniable in cancer, there are still complications associated with their therapeutic use. Moreover, there is an absence of sufficient experiments regarding their application in mouse models, which is an area to work on. By emphasizing the crucial role of ncRNAs, this review underscores the need for innovative approaches and further studies to explore their potential in cancer therapy.

Extracellular Vesicle-Derived miRNAs in Ischemic Stroke: Roles in Neuroprotection, Tissue Regeneration, and Biomarker Potential

Ischemic stroke (IS) is one of the most common causes of death and disability worldwide. Despite its prevalence, knowledge about pathophysiology and diagnostic methods remains limited. Extracellular vesicles (EVs) that are released from cellular membranes constitutively, as well as after activation or damage, may contain various intracellular particles, including microRNAs (miRNAs/miR). miRNAs acting as mRNA transcription regulators are secreted in EVs and may be internalized by other cells. This cellular cross-talk is important for the regeneration of the nervous tissue after ischemic injury. Moreover, miRNAs related to stroke pathophysiology were shown to be differentially expressed after an IS episode. miRNAs associated with various types of stem cell-derived EVs were shown to be involved in post-ischemic neuroprotection and tissue regeneration and may be potential therapeutic agents. Therefore, considering their stability in plasma, they are worth investigating also as potential diagnostic/prognostic biomarkers. The present review summarizes the current knowledge about EV-derived miRNAs in the neuronal injury mechanism and their potential in neuroprotection in IS, and discusses the possibilities of further investigation of their use in preclinical research.

Role of noncoding RNA as a pacemaker in cancer stem cell regulation: a review article

Accumulated evidence supported the crucial role of a tiny population of cells within the tumor called cancer stem cells (CSCs) in cancer origination, and proliferation. Additionally, these cells are distinguished by their self-renewal, differentiation, and therapeutic resistance capabilities. Interestingly, many studies recorded dysregulation of different types of noncoding RNAs, such as microRNA (miRNA) and long non-coding RNA (LncRNA), in cancer cells as well as CSCs. Moreover, several studies also supported the regulation of the transcription factors and signaling pathways required for CSC progression by these noncoding RNAs. However, the exact biological functions of all these noncoding RNAs are not well understood yet. These findings are of great interest, implying usage of noncoding RNA as therapeutic tool to target these cells. In this review, we provide an insight into how noncoding RNAs regulate CSCs and how this correlation is manipulated to develop new therapies to eradicate cancer cells successfully.

Liquid biopsies in cancer

Cancer ranks among the most lethal diseases worldwide. Tissue biopsy is currently the primary method for the diagnosis and biological analysis of various solid tumors. However, this method has some disadvantages related to insufficient tissue specimen collection and intratumoral heterogeneity. Liquid biopsy is a noninvasive approach for identifying cancer-related biomarkers in peripheral blood, which allows for repetitive sampling across multiple time points. In the field of liquid biopsy, representative biomarkers include circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), and exosomes. Many studies have evaluated the prognostic and predictive roles of CTCs and ctDNA in various solid tumors. Although these studies have limitations, the results of most studies appear to consistently demonstrate the correlations of high CTC counts and ctDNA mutations with lower survival rates in cancer patients. Similarly, a reduction in CTC counts throughout therapy may be a potential prognostic indicator related to treatment response in advanced cancer patients. Moreover, the biochemical characteristics of CTCs and ctDNA can provide information about tumor biology as well as resistance mechanisms against targeted therapy. This review discusses the current clinical applications of liquid biopsy in cancer patients, emphasizing its possible utility in outcome prediction and treatment decision-making.

miRNA-dependent resistance mechanisms to anti-hormonal therapies in estrogen receptor-positive breast cancer patients

The estrogen receptor (ERα) is expressed in 70%-80% of breast cancers and is a target of endocrine therapy. However, resistance to endocrine therapy poses a significant clinical challenge. MicroRNAs (miRNAs) have emerged as critical players in oncogenesis and as modulators of therapy response. This review provides an overview of miRNAs that modulate anti-hormonal drug responses. We identified 56 miRNAs associated with resistance to endocrine therapy. These miRNAs had a total of 40 proven target genes that were grouped based on their function under currently known resistance mechanisms, including ER modulation, signaling pathway activation, cell-cycle modulation, and other mechanisms. For a limited number of miRNA-target gene interactions, the relevance of the identified target gene(s) was confirmed by copy or rescue of the miRNA-induced phenotype. Overall, this review highlights critical roles of miRNAs as crucial mediators of resistance to anti-hormonal therapy. The identified miRNA-target gene interactions can serve as a foundation for future functional studies exploring the potential of selected miRNAs in overcoming drug resistance, which might improve outcomes for breast cancer patients.

Evaluation of Boric Acid Treatment on microRNA-127-5p and Metastasis Genes Orchestration of Breast Cancer Stem Cells

Coregulation of microRNAs (miRNAs) and cancer stem cells (CSCs) is very important in carcinogenesis. miR-127-5p is known to be downregulated in breast cancer. In this study, we aimed to investigate how boric acid (BA), known for its previously unstudied anti-cancer properties, would affect the expression of miR127-5p and genes responsible for breast cancer stem cells (BC-SCs) metastasis. BC-SCs were isolated from human breast cancer cells (MCF-7) by immunomagnetic cell separation and characterized with flow cytometry and sphere formation. The viability of BC-SCs and the determination of its IC50 value in response to boric acid (BA) were assessed via the MTT assay. Boric acid exhibited dose- and time-dependent inhibition of cell viability in cells. The IC50 doses of boric acid in MCF-7 cells and BC-SCs were 45.69 mM and 41.27 mM, respectively. The impact of BA on the expression of metastatic genes and miR127-5p was elucidated through RT-qPCR analysis. While the expression of the COL1A1 (p < 0.05) and VIM (p < 0.01) was downregulated, the expression of the miR-127-5p, ZEB1 (p < 0.01), CDH1 (p < 0.05), ITGB1 (p < 0.05), ITGA5 (p < 0.05), LAMA5 (p < 0.01), and SNAIL (p < 0.05), was up-regulated in dose-treated BC-SCs (p < 0.001) to the RT-qPCR results. Our findings suggest that boric acid could induce miR-127-5p expression. However, it cannot be said that it improves the metastasis properties of breast cancer stem cells.

Evaluating MicroRNAs as diagnostic tools for lymph node metastasis in breast cancer: Findings from a systematic review and meta-analysis

Lymph node metastasis (LNM) significantly affects the prognosis and clinical management of breast cancer (BC) patients. This systematic review and meta-analysis aim to identify microRNAs (miRNAs) associated with LNM in BC and evaluate their potential diagnostic and prognostic value. Following PRISMA guidelines, a comprehensive literature search was conducted in PubMed, Web of Science, and SCOPUS databases, to assess the role of miRNAs in LNM BC. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was used to evaluate the quality of included studies. A total of 84 miRNAs were identified as differentially expressed in BC patients with LNM. Of these, a meta-analysis was performed in two microRNAs that were present in at least 3 different articles with a coherent expression direction: miR-155 and miR-34a. The meta-analysis returned a pooled a Log2 fold change of 1.50 for miR-155 (upregulated) and -0.53 for miR-34a (downregulated) with no evidence of publication bias, and a low risk of bias and applicability concerns. To conclude, this study names miR-155 and miR-34a as potential diagnostic biomarkers for LNM in BC, although further experimental validation is necessary to confirm these findings and develop non-invasive diagnostic tools for clinical use.

Extracellular vesicles-derived miR-21 as a biomarker for early diagnosis and tumor activity in breast cancer subtypes

Emerging evidence highlights the key role of microRNA (miR)-21 in cell-to-cell communication and tumorigenesis. However, limited knowledge exists on the levels and clinical meaning of miR-21 in extracellular vesicles (EVs) of patients with breast cancer (BC). We assessed EV-derived miR-21 levels in one hundred women: 30 with early BC (EBC), 30 with metastatic BC on treatment progression (MBC), 30 cancer survivors on follow-up (FU) and 10 healthy donors (HD) as age- and body mass index (BMI)-matched controls. EVs isolated from serum samples were characterized using nanoparticle tracking analysis, scanning electron microscopy and atomic force microscopy to detect their concentration, size, morphology and mechanical properties. The levels of miR-21 in EVs was evaluated using real time PCR and compared between groups (EBC, MBC and FU vs. HD) by calculating the fold change and ΔΔCt statistic. EVs size and concentration did not differ significantly among patient groups. In the EBC group, the clinical stage at diagnosis and tumor subtype did not influence miR-21 levels. The levels of miR-21 were higher in the MBC group than in the HD group (p = 0.029), mainly in those who were human epidermal growth factor receptor 2 (HER2)+ (p = 0.0005) and hormone receptor-positive (p = 0.036). In particular, in the HER2 + subgroup, the miR-21 levels were significantly higher in those with active BC (both EBC and MBC) than in HDs (p = 0.002). Our findings suggest that miR-21 may be a promising biomarker for diagnosis and tumor activity, mainly in HER2 + BC.

The Combined Impact of Curcumin: Piperine and Sorafenib on microRNAs and Different Pathways in Breast Cancer Cells

Breast cancer is the most common malignancy in the women. Chemotherapy is a crucial part of breast cancer treatment especially for advanced and metastatic forms of the disease. However, chemotherapy has limitations due to tumor heterogeneity, chemoresistance, and side effects. There is potential in combining chemotherapeutic drugs with natural items to enhance their effectiveness against cancer. In this study, we examined the synergistic effects of combining curcumin: piperine with sorafenib on the progression of breast cancer cells by altering many pathways associated with cancer and regulating the expression of numerous microRNAs. We tested the cytotoxic impact of curcumin: piperine on MCF-7 breast cancer cells using SRB assay. We analyzed the expression levels of selected microRNAs, genes, and proteins related to cancer stem cells, epithelial-mesenchymal transition, apoptosis and cell cycle progression using qPCR, ELISA and flow cytometry techniques. The findings of this study demonstrated that sorafenib and curcumin: piperine together enhances the suppression of MCF-7 cell survival. Molecular genetic analysis revealed that this combination provoked downregulation in oncomirs [miR-21 and miR-155], vimentin, Snail1, Notch, TGF-β1, Smad4, β-catenin1 and Wnt10b genes. Meanwhile, there were upregulation of tumor suppressor miRNAs [miR-28, miR-139 and miR-149] and E-cadherin gene expression level. Also, this combination resulted in a decrease of vimentin, IL-6, STAT3 and MMP-9; an increase of E-cadherin protein levels. Moreover, this combination induced apoptotic cell death and arrested cell cycles at specific phases. This study suggests that the combination of sorafenib and curcumin: piperine can combat breast cancer by modulating several microRNAs and signaling pathways involved in the development and progression of breast cancer.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12291-024-01212-0.

Exosomal microRNAs: impact on cancer detection, treatment, and monitoring

Exosomes, measuring between 30 and 150 nm in diameter, are small vesicles enclosed by a lipid bilayer membrane. They are released by various cells in the body and carry a diverse payload of molecules, including proteins, lipids, mRNA, and different RNA species such as long non-coding RNA, circular RNA, and microRNA (miRNA). With lengths of approximately 19-22 nucleotides, miRNAs constitute the predominant cargo in exosomes and serve as crucial regulators of protein biosynthesis. In cancer detection, exosomal miRNAs show promise as non-invasive biomarkers due to their stability and presence in various bodily fluids, aiding in early detection and precise diagnosis with specific miRNA signatures linked to different cancer types. Moreover, exosomal miRNAs influence treatment outcomes by affecting cellular processes like cell growth, cell death, and drug resistance, thereby impacting response to therapy. Additionally, they serve as indicators of disease progression and treatment response, providing insights that can guide treatment decisions and improve patient care. Through longitudinal studies, changes in exosomal miRNA profiles have been observed to correlate with disease progression, metastasis, and response to therapy, highlighting their potential for real-time monitoring of tumor dynamics and treatment efficacy. Understanding the intricate roles of exosomal miRNAs in cancer biology offers opportunities for developing innovative diagnostic tools and therapeutic strategies tailored to individual patients, ultimately advancing precision medicine approaches and improving outcomes for cancer patients. This review aims to provide an understanding of the role of exosomal miRNAs in cancer detection, treatment, and monitoring, shedding light on their potential for revolutionising oncology practices and patient care.

Dysregulation of MiR-21, MiR-221 and MiR-451 During Neoadjuvant Treatment of Breast Cancer: A Prospective Study

BACKGROUND

Breast cancer is highly heterogeneous disease in which different responses are observed to the same treatment for different subtypes and extents of similar diseases. Considering this scenario, the search for tumor biomarkers is indispensable, with current evidence suggesting that circulating microRNAs are viable biomarkers. This study evaluated the expression of miR-21, miR-221, miR-195, and miR-451 in patients with breast cancer undergoing neoadjuvant treatment at oncology outpatient facilities in Brazil.

METHODS

We conducted a prospective and observational study in which blood samples were collected for microRNA expression analysis, comparing control and breast cancer patients who were candidates for neoadjuvant treatment groups. The expression of microRNAs was investigated by qRT-PCR method. For parametric data analysis, one-way ANOVA with Tukey's post hoc test was used.

RESULTS

Thirty-three participants (all female) were included in the control group and twenty-seven participants were included in the study group. The non-special subtype of breast cancer was found in 96% of the study group participants; 88.9% were locally advanced tumors (T3, T4), 40.7% were luminal tumors, 33.3% were HER-2-positive, and 26% were triple negative tumors. Expression analysis of microRNAs during neoadjuvant treatment, using miR-16 as a normalizer, showed higher expression levels of miR-21 and miR-221 at the end of treatment, and high expression levels for miR-451 were also observed at the beginning of treatment.

CONCLUSION

This is the first study that evaluates the expression of microRNAs in the context of neoadjuvant treatment of breast cancer in the Brazilian population. Our results suggest that there is a deregulation of miR-21, miR-221, and miR-451 during neoadjuvant treatment in these patients.

Exploring the role of microRNAs as diagnostic and prognostic biomarkers in canine mammary tumors

Canine mammary tumors (CMTs) represent a significant health concern in dogs, with a high incidence among intact female dogs. CMTs are a promising comparative model for human breast cancer, due to sharing several pathophysiological features. Additionally, CMTs have a strong genetic correlation with their human counterpart, including the expression of microRNAs (miRNAs). MiRNAs are a class of non-coding RNAs that play important roles in post-translational regulation of gene expression, being implicated in carcinogenesis, tumor progression, and metastasis. Moreover, miRNAs hold promise as diagnostic, prognostic, and metastatic biomarkers. Understanding the molecular mechanisms underlying CMTs is crucial for improving diagnosis, prognosis, and monitoring of treatments. Herein, we provide a comprehensive overview of the current knowledge on miRNAs in CMTs, highlighting their roles in carcinogenesis and their potential as biomarkers. Additionally, we highlight the current limitations and critically discuss the overarching challenges in this field, emphasizing the need for future research to translate miRNA findings into veterinary clinical practice.

Circulating Micro-RNAs Predict the Risk of Recurrence in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with a high tendency for developing a recurrent disease. Circulating micro-RNAs (cmiRNAs) obtained through liquid biopsy are potential prognostic biomarkers for the assessment of TNBC recurrence risk. In this study, we sequenced cmiRNAs from the serum samples of 14 recurrent and 19 non-recurrent TNBC cases and compared expression profiles in relation to recurrence status, survival data and miRNA expression in matched tumor samples. Differential expression analysis between recurrent and non-recurrent cases identified ten differentially expressed (DE) cmiRNAs, of which cmiRNAs miR-21-5p (p = 0.030, HR = 1.87, 95% CI 1.06-3.30), miR-16-5p (p = 0.032, HR = 0.53, 95% CI 0.30-0.95), and miR-26b-5p (p = 0.023, HR = 0.52, 95% CI 0.29-0.91) were associated with recurrence-free survival in multivariable survival analysis. Expression profiles of matched tumor and serum samples were shown to correlate with each other. DE cmiRNAs were associated with common cancer-related signaling pathways and improved the overall predictive performance of the logistic regression model assessing the recurrence risk. Our results indicate that recurrent and non-recurrent TNBC differ in their cmiRNA expression profiles, and that three specific cmiRNAs can be used to assess the risk of recurrence in TNBC.

Profiles of differential expression of miRNAs in the late stage of red blood cell preservation and their potential roles

OBJECTIVE

To detect the differentially expressed regulatory miRNAs in the late stage of red blood cell (RBC) preservation and predict their roles.

METHODS

Suspended RBCs with different storage periods of 35 day, 42 day, and 50 day were collected for routine blood tests, RNA extraction, and preparation of small RNA sequencing libraries. The constructed libraries were sequenced and the biological functions of differential miRNAs in RBCs in the late storage were analyzed by bioinformatics.

RESULTS

Routine indicators of RBCs in the late stage were not significantly affected by preservation time. The Pearson correlation analysis performing on RBC miRNAs with different storage days revealed that RBC miRNAs changed with the increase of storage days. RBC miRNAs from day 35 (D35), day 42 (D42) and day 50 (D50) showed significant differences (P < 0.05). Compared RBC miRNAs from D42 with these from D35, there were 690 up-regulated miRNAs and 82 down-regulated miRNAs; compared RBC miRNAs from D50 with these from D35, there were 638 up-regulated miRNAs and 123 down-regulated miRNAs; compared RBC miRNAs from D42 with these from D50, there were 271 up-regulated miRNAs and 515 down-regulated miRNAs. GO enrichment analysis of target genes of differential miRNAs were mainly involved in cell metabolism, biosynthesis, protein modification, gene expression and transcriptional regulation of biological processes. KEGG pathway enrichment analysis of miRNA target genes showed that differential miRNA target genes were closely related to pathways in cancer.

CONCLUSION

MiRNAs were differentially expressed in the late stage of RBC preservation, and may be involved in various biological processes, especially cancer.

MicroRNA-21 (miR-21) in breast cancer: From apoptosis dysregulation to therapeutic opportunities

Breast cancer, a pervasive and complex disease, continues to pose significant challenges in the field of oncology. Its heterogeneous nature and diverse molecular profiles necessitate a nuanced understanding of the underlying mechanisms driving tumorigenesis and progression. MicroRNA-21 (miR-21) has emerged as a crucial player in breast cancer development and progression by modulating apoptosis, a programmed cell death mechanism that eliminates aberrant cells. MiR-21 overexpression is a hallmark of breast cancer, and it is associated with poor prognosis and resistance to conventional therapies. This miRNA exerts its oncogenic effects by targeting various pro-apoptotic genes, including Fas ligand (FasL), programmed cell death protein 4 (PDCD4), and phosphatase and tensin homolog (PTEN). By suppressing these genes, miR-21 promotes breast cancer cell survival, proliferation, invasion, and metastasis. The identification of miR-21 as a critical regulator of apoptosis in breast cancer has opened new avenues for therapeutic intervention. This review investigates the intricate mechanisms through which miR-21 influences apoptosis, offering insights into the molecular pathways and signaling cascades involved. The dysregulation of apoptosis is a hallmark of cancer, and understanding the role of miR-21 in this context holds immense therapeutic potential. Additionally, the review highlights the clinical significance of miR-21 as a diagnostic and prognostic biomarker in breast cancer, underscoring its potential as a therapeutic target.

Targeting the Akt signaling pathway: Exploiting curcumin's anticancer potential

Cancer is recognized as one of the leading causes of death worldwide. In recent years, advancements in early detection and expanding treatment options have contributed to a decrease in mortality rates. However, the emergence of drug-resistant cancers necessitates the exploration of innovative and more effective drugs. The Akt kinases play a central role in various signaling pathways that regulate crucial cellular processes, including cell growth, proliferation, survival, angiogenesis, and glucose metabolism. Due to frequent disruptions of the Akt signaling pathway in numerous human cancers and its broad biological implications, targeting this pathway has become a key focus in combating tumor aggressiveness and a promising avenue for therapeutic intervention. Curcumin, a compound found in turmeric, has been extensively studied for its potential as an anti-cancer agent. It demonstrates inhibitory effects on cancer initiation, progression, and metastasis by influencing various processes involved in tumor growth and development. These effects are achieved through negative regulation of transcription factors, growth factors, cytokines, protein kinases, and other oncogenic molecules. This review aims to explore curcumin's anticancer activity against different types of cancer mediated via the PI3K/Akt signaling pathway, as well as its practical applications in treatment.

Impact of Molecular Profiling on Therapy Management in Breast Cancer

Breast cancer (BC) remains the most prevalent cancer among women and the leading cause of cancer-related mortality worldwide. The heterogeneity of BC in terms of histopathological features, genetic polymorphisms, and response to therapies necessitates a personalized approach to treatment. This review focuses on the impact of molecular profiling on therapy management in breast cancer, emphasizing recent advancements in next-generation sequencing (NGS) and liquid biopsies. These technologies enable the identification of specific molecular subtypes and the detection of blood-based biomarkers such as circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), and tumor-educated platelets (TEPs). The integration of molecular profiling with traditional clinical and pathological data allows for more tailored and effective treatment strategies, improving patient outcomes. This review also discusses the current challenges and prospects of implementing personalized cancer therapy, highlighting the potential of molecular profiling to revolutionize BC management through more precise prognostic and therapeutic interventions.

MicroRNAs as promising biomarkers and potential therapeutic agents in breast cancer management: a comprehensive review

Breast cancer (BC), a complex and varied ailment, poses a significant global health burden. MicroRNAs (miRNAs) have emerged as vital regulators in BC progression, with potential implications for diagnosis and treatment. This review aims to synthesize current insights into miRNA dysregulation in BC. MiRNAs, small RNA molecules, govern gene expression post-transcriptionally and are implicated in BC initiation, metastasis, and therapy resistance. Differential expression of specific miRNAs in BC tissues versus normal breast tissue sheds light on underlying molecular mechanisms. MiRNAs also offer promise as diagnostic biomarkers due to their stable nature, accessibility in bodily fluids, and altered expression patterns in early-stage disease, augmenting conventional diagnostic methods. Beyond diagnosis, miRNAs also hold promise as therapeutic targets in BC. By modulating the expression of specific dysregulated miRNAs, it may be possible to restore normal cellular functions and overcome treatment resistance. However, several challenges need to be addressed before miRNA-based therapies can be translated into clinical practice, including the development of efficient delivery systems and rigorous evaluation through preclinical and clinical trials. MiRNAs represent a promising avenue in BC research, offering potential applications in diagnosis, prognosis, and therapeutic interventions. As our understanding of miRNA biology deepens and technology advances, further research and collaborative efforts are needed to fully exploit the diagnostic and therapeutic potential of miRNAs in BC management. Ultimately, the integration of miRNA-based approaches into clinical practice may lead to more personalized and effective strategies for combating this devastating disease.

IDMIR: identification of dysregulated miRNAs associated with disease based on a miRNA-miRNA interaction network constructed through gene expression data

Micro ribonucleic acids (miRNAs) play a pivotal role in governing the human transcriptome in various biological phenomena. Hence, the accumulation of miRNA expression dysregulation frequently assumes a noteworthy role in the initiation and progression of complex diseases. However, accurate identification of dysregulated miRNAs still faces challenges at the current stage. Several bioinformatics tools have recently emerged for forecasting the associations between miRNAs and diseases. Nonetheless, the existing reference tools mainly identify the miRNA-disease associations in a general state and fall short of pinpointing dysregulated miRNAs within a specific disease state. Additionally, no studies adequately consider miRNA-miRNA interactions (MMIs) when analyzing the miRNA-disease associations. Here, we introduced a systematic approach, called IDMIR, which enabled the identification of expression dysregulated miRNAs through an MMI network under the gene expression context, where the network's architecture was designed to implicitly connect miRNAs based on their shared biological functions within a particular disease context. The advantage of IDMIR is that it uses gene expression data for the identification of dysregulated miRNAs by analyzing variations in MMIs. We illustrated the excellent predictive power for dysregulated miRNAs of the IDMIR approach through data analysis on breast cancer and bladder urothelial cancer. IDMIR could surpass several existing miRNA-disease association prediction approaches through comparison. We believe the approach complements the deficiencies in predicting miRNA-disease association and may provide new insights and possibilities for diagnosing and treating diseases. The IDMIR approach is now available as a free R package on CRAN (https://CRAN.R-project.org/package=IDMIR).

Microsphere-Enhanced Fluorescence-Lightened Solid-Phase Hybridization Assay: The Strategy to Highly Selective Detection of Micro Ribonucleic Acids

The detection of low-abundance microribonucleic acid (miRNA) frequently adopted nucleic acid sequence-based amplification detection, which was found to have poor selectivity for the nonspecific amplification of template-dependent ligation in enzyme-mediated cascade reactions. Here, a highly selective detection of miRNAs was developed that combined microsphere-enhanced fluorescence (MSEF) and solid-phase base-paired hybridization. The target miRNA could be accurately and quantitatively identified through the solid-phase hybridization assay on the surface of an optical microsphere, while the detected fluorescence signal could be physically amplified by MSEF. Hereinto, the optical microsphere acted as the fluorescence amplifier and whose surface supplied the space to carry out base-paired hybridization to recognize the target miRNA via the immobilized capture DNA sequence. The detected fluorescence signal of the single-base mismatched miRNA-21 sequence was just around 12% of that of the target miRNA-21 sequence in the measurement of model miRNA-21, while the limit of detection of miRNA-21 could be 1.0 fM. The developed detection of miRNA on an optical microsphere was demonstrated to be an excellent physically amplified method to selectively and sensitively detect the target miRNA and magnificently avoid the nonspecific amplification and false-positive results, which is expected to have wide applications in pathematology, pharmacology, clinic diagnosis, and on-site screening fields as well.

BRCA Mutations and MicroRNA Expression Patterns in the Peripheral Blood of Breast Cancer Patients

Breast cancer (BC) persists as the predominant malignancy globally, standing as the foremost cause of cancer-related mortality among women. Despite notable advancements in prevention and treatment, encompassing the incorporation of targeted immunotherapies, a continued imperative exists for the development of innovative methodologies. These methodologies would facilitate the identification of women at heightened risk, enhance the optimization of therapeutic approaches, and enable the vigilant monitoring of emergent treatment resistance. Circulating microRNAs (miRNAs), found either freely circulating in the bloodstream or encapsulated within extracellular vesicles, have exhibited substantial promise for diverse clinical applications. These applications range from diagnostic and prognostic assessments to predictive purposes. This study aimed to explore the potential associations between BRCA mutations and specific miRNAs (miR-21, miR-155, miR-126, and miR-200c) expression that are known to be dysregulated in BC patient samples. Our findings indicate a robust correlation between miRNA expression status and disease subtypes. We found a correlation between the expression status of miRNAs and distinct disease subtypes. Intriguingly, however, no significant associations were discerned between disease status, subtypes, or miRNA expression levels and the presence of BRCA mutations. To advance the validation of miRNAs as clinically relevant biomarkers, additional investigations within larger and meticulously selected patient cohorts are deemed imperative. These microRNA entities hold the potential to emerge as groundbreaking and readily accessible tools, poised for seamless integration into the landscape of clinical practice.

Research progress and applications of epigenetic biomarkers in cancer

Epigenetic changes are heritable changes in gene expression without changes in the nucleotide sequence of genes. Epigenetic changes play an important role in the development of cancer and in the process of malignancy metastasis. Previous studies have shown that abnormal epigenetic changes can be used as biomarkers for disease status and disease prediction. The reversibility and controllability of epigenetic modification changes also provide new strategies for early disease prevention and treatment. In addition, corresponding drug development has also reached the clinical stage. In this paper, we will discuss the recent progress and application status of tumor epigenetic biomarkers from three perspectives: DNA methylation, non-coding RNA, and histone modification, in order to provide new opportunities for additional tumor research and applications.

Circulating miRNA-21 Levels in Breast Cancer Patients Before and After Chemotherapy and Its Association with Clinical Improvement

Breast cancer is the most frequent type of cancer in women, many patients experience recurrences and metastasis. miR-21 (microRNA-21) as biomarker is under investigation for breast cancer. At present, there is very limited information available regarding effect of chemotherapy on miR-21 expression in breast cancer and its correlation with the clinical improvement. Hence, this study was planned to evaluate the effect of chemotherapy on miR-21 in metastatic breast cancer and its relationship with the clinical outcome. Females, aged-18-90 years diagnosed with Invasive Ductal Carcinoma of breast and candidate of neoadjuvant chemotherapy including Adriamycin (60 mg/m2), Cyclophosphamide (600 mg/m2) with or without Taxane (75-175 mg/m2) were included in the study. Before and after 42 days of staring of chemotherapy sample was collected for circulatory miR-21 and RECIST 1.1 criteria was applied to assess the clinical status. Blood samples for routine clinical biomarkers including liver function test and renal function tests was also collected. miR-21 expression before and after chemotherapy was assessed using standard method based on real time PCR. Expression of miR-21, RECIST criteria and other liver and kidney related biomarkers were compared before and after chemotherapy. After neoadjuvant chemotherapy expression of miR-21 was significantly increased by 5.65-fold. There was significant improvement in clinical scores based on RECIST criteria (0.046). No significant correlation was observed between miR-21 expression and difference in RECIST score (r = - 0.122, p = 0.570). Neoadjuvant chemotherapy causes clinical improvement in breast cancer patients however it is not correlated with the miR-21 expression which significantly increased after chemotherapy.

Exploring the contrasts: in-depth analysis of human and canine mammary tumors - discoveries at the frontier

We have examined genomic and transcriptomic abnormalities in human and canine samples to evaluate the canine model's validity for breast cancer research, emphasizing similarities and differences. Both species commonly utilize serum tumor markers and noncoding microRNAs. Immunohistochemistry and immunocytochemistry were employed to illustrate and compare results based on histological diagnoses. In addition to these factors, similarities exist in spontaneous tumor occurrence, age of onset, hormonal influences, and disease progression, including tumor size, clinical stage, and lymph node involvement. Molecular traits such as hormone receptor status, Epidermal Growth Factor Receptor (EGFR), and proliferation markers (Ki67) further endorse the canine model's utility in breast cancer studies. The advancement of technologies facilitates the identification of new cancer-associated molecules, both coding and non-coding genes, underscoring their potential as prognostic/diagnostic biomarkers and therapeutic targets.

Non-coding RNAs in disease: from mechanisms to therapeutics

Non-coding RNAs (ncRNAs) are a heterogeneous group of transcripts that, by definition, are not translated into proteins. Since their discovery, ncRNAs have emerged as important regulators of multiple biological functions across a range of cell types and tissues, and their dysregulation has been implicated in disease. Notably, much research has focused on the link between microRNAs (miRNAs) and human cancers, although other ncRNAs, such as long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), are also emerging as relevant contributors to human disease. In this Review, we summarize our current understanding of the roles of miRNAs, lncRNAs and circRNAs in cancer and other major human diseases, notably cardiovascular, neurological and infectious diseases. Further, we discuss the potential use of ncRNAs as biomarkers of disease and as therapeutic targets.

MicroRNA signatures differentiate types, grades, and stages of breast invasive ductal carcinoma (IDC): miRNA-target interacting signaling pathways

BACKGROUND

Invasive ductal carcinoma (IDC) is the most common form of breast cancer which accounts for 85% of all breast cancer diagnoses. Non-invasive and early stages have a better prognosis than late-stage invasive cancer that has spread to lymph nodes. The involvement of microRNAs (miRNAs) in the initiation and progression of breast cancer holds great promise for the development of molecular tools for early diagnosis and prognosis. Therefore, developing a cost effective, quick and robust early detection protocol using miRNAs for breast cancer diagnosis is an imminent need that could strengthen the health care system to tackle this disease around the world.

METHODS

We have analyzed putative miRNAs signatures in 100 breast cancer samples using two independent high fidelity array systems. Unique and common miRNA signatures from both array systems were validated using stringent double-blind individual TaqMan assays and their expression pattern was confirmed with tissue microarrays and northern analysis. In silico analysis were carried out to find miRNA targets and were validated with q-PCR and immunoblotting. In addition, functional validation using antibody arrays was also carried out to confirm the oncotargets and their networking in different pathways. Similar profiling was carried out in Brca2/p53 double knock out mice models using rodent miRNA microarrays that revealed common signatures with human arrays which could be used for future in vivo functional validation.

RESULTS

Expression profile revealed 85% downregulated and 15% upregulated microRNAs in the patient samples of IDC. Among them, 439 miRNAs were associated with breast cancer, out of which 107 miRNAs qualified to be potential biomarkers for the stratification of different types, grades and stages of IDC after stringent validation. Functional validation of their putative targets revealed extensive miRNA network in different oncogenic pathways thus contributing to epithelial-mesenchymal transition (EMT) and cellular plasticity.

CONCLUSION

This study revealed potential biomarkers for the robust classification as well as rapid, cost effective and early detection of IDC of breast cancer. It not only confirmed the role of these miRNAs in cancer development but also revealed the oncogenic pathways involved in different progressive grades and stages thus suggesting a role in EMT and cellular plasticity during breast tumorigenesis per se and IDC in particular. Thus, our findings have provided newer insights into the miRNA signatures for the classification and early detection of IDC.

A pilot study to evaluate the expression of microRNA‑let‑7a in patients with intestinal‑type sinonasal adenocarcinoma

Despite its histological resemblance to colorectal adenocarcinoma, there is little information about the molecular events involved in the pathogenesis of intestinal-type sinonasal adenocarcinoma (ITAC). The present study investigated the possible role and clinical value of microRNA (miR)-let-7a, a head and neck squamous cell carcinoma-related miR, in a well-characterized and homogeneous cohort of patients with ethmoidal ITAC associated with occupational exposure, treated by primary surgery. miR-let-7a expression levels were analyzed in 23 pairs of ethmoidal ITAC and adjacent normal formalin-fixed paraffin-embedded tissues by reverse transcription-quantitative PCR. The expression was evaluated in tumor and healthy tissues according to: Tumor grade (G) of differentiation and extension, and pTNM stage, and presence/absence of recurrence. Comparisons within and between groups were performed using two-tailed Student's paired t-test and one-way ANOVA with Tukey's post hoc test. P<0.05 was considered to indicate a statistically significant difference. miR-let-7a expression in ethmoidal ITAC tissues was significantly lower than that in adjacent normal tissues (P<0.05; mean expression level ± SD, 1.452707±1.4367189 vs. 4.094017±2.7465375). miR expression varied with pT stage. miR-let-7a was downregulated (P<0.05) in advanced stages (pT3-pT4) compared with earlier stages (pT1-pT2). Furthermore, downregulation of miR-let-7a in ITAC was associated with poorly-differentiated (G3) cancer (P<0.05). No other associations were observed between miR-let-7a expression and the other clinicopathological parameters, including disease-free survival. In conclusion, downregulation of miR-let-7a in ITAC was associated with advanced-stage (pT3 and pT4) and poorly-differentiated (G3) disease, suggesting that the mutation of this gene, combined with additional genetic events, could serve a role in ITAC pathogenesis.

Association of microRNA-21 expression with breast cancer subtypes and its potential as an early biomarker

Breast cancer has become the most diagnosed cancer worldwide in 2020 with high morbidity and mortality rates. The alarming increase in breast cancer incidence has sprung many researchers to focus on developing novel screening tests to identify early breast cancer which will allow clinicians to provide timely and effective treatments. With much evidence supporting the notion that the deregulation of miRNAs (a class of non-coding RNA) greatly contributes to cancer initiation and progression, the promising role of miRNAs as cancer biomarkers is gaining traction in the research world. Among the upregulated miRNAs identified in breast carcinogenesis, miR-21 was shown to be significantly expressed in breast cancer tissues and bodily fluids of breast cancer patients. Therein, this review paper aims to provide an overview of breast cancer, the role and significance of miR-21 in breast cancer pathogenesis, and its potential as a breast cancer biomarker. The paper also discusses the current types of tumor biomarkers and their limitations, the presence of miR-21 in extracellular vesicles and plasma, screening methods available for miRNA detection along with some challenges faced in developing diagnostic miR-21 testing for breast cancer to provide readers with a comprehensive outlook based on using miR-21 in clinical settings.

microRNAs expression profile in phyllodes tumors of the breast

Proliferation of both stromal and epithelial components is a characteristic of fibroepithelial cancers of the breast. Certain fibroepithelial tumors of the breast, such as fibradenomas and phyllodes tumors, are challenging to distinguish and categorize. To find biomarkers for early diagnosis and improved disease management, it is crucial to deepen our understanding of the molecular pathogenesis pathways and tumor biology of PTs. It has been demonstrated that microRNAs (miRNAs) have significant roles in cancers; the expression pattern of miRNAs can help with cancer categorization and treatment. In contrast, little is understood about miRNAs in breast fibroepithelial cancers. This study was conducted retrospectively with the goal of assessing the expression of six mature miRNAs (hsa-miR-21, hsa-miR-155, hsa-miR-182, hsa-miR-34a, hsa-miR-148a, and hsa-miR-205) in breast fibroepithelial cancers using real-time PCR and predicting these miRNAs' targets using computational techniques. This study comprised 64 patients in total-55 with phyllodes tumors and 9 with fibroadenoma. The research was carried out at the Farhat Hached University Hospital's pathology department in Tunisia. These particular miRNAs expression levels were evaluated via qRT-PCR, and in silico techniques were utilized to predict potential miRNA targets. Analysis of miRNA expression in fibroadenoma and phyllodes tumor tissues revealed that miR-21, miR-155 and miR-182 were upregulated in PTs compared to fibroadenoma and normal tissues. We reported that miR-34a, miR-148a and miR-205 were downregulated in both borderline and malignant PTs compared to fibroadenoma and normal tissue. In silico miRNA target prediction suggested the involvement of these molecules in a wide context of cell signaling pathways.

Epigenetic modulation of antitumor immunity and immunotherapy response in breast cancer: biological mechanisms and clinical implications

Breast cancer (BC) is the most common non-skin cancer and the second leading cause of cancer death in American women. The initiation and progression of BC can proceed through the accumulation of genetic and epigenetic changes that allow transformed cells to escape the normal cell cycle checkpoint control. Unlike nucleotide mutations, epigenetic changes such as DNA methylation, histone posttranslational modifications (PTMs), nucleosome remodeling and non-coding RNAs are generally reversible and therefore potentially responsive to pharmacological intervention. Epigenetic dysregulations are critical mechanisms for impaired antitumor immunity, evasion of immune surveillance, and resistance to immunotherapy. Compared to highly immunogenic tumor types, such as melanoma or lung cancer, breast cancer has been viewed as an immunologically quiescent tumor which displays a relatively low population of tumor-infiltrating lymphocytes (TIL), low tumor mutational burden (TMB) and modest response rates to immune checkpoint inhibitors (ICI). Emerging evidence suggests that agents targeting aberrant epigenetic modifiers may augment host antitumor immunity in BC via several interrelated mechanisms such as enhancing tumor antigen presentation, activation of cytotoxic T cells, inhibition of immunosuppressive cells, boosting response to ICI, and induction of immunogenic cell death (ICD). These discoveries have established a highly promising basis for using combinatorial approaches of epigenetic drugs with immunotherapy as an innovative paradigm to improve outcomes of BC patients. In this review, we summarize the current understanding of how epigenetic processes regulate immune cell function and antitumor immunogenicity in the context of the breast tumor microenvironment. Moreover, we discuss the therapeutic potential and latest clinical trials of the combination of immune checkpoint blockers with epigenetic agents in breast cancer.

Spatiotemporally Programmed Disassembly of Multifunctional Integrated DNAzyme Nanoplatfrom for Amplified Intracellular MicroRNA Imaging

The sensing performance of DNAzymes in live cells is tremendously hampered by the inefficient and inhomogeneous delivery of DNAzyme probes and their incontrollable off-site activation, originating from their susceptibility to nuclease digestion. This requires the development of a more compact and robust DNAzyme-delivering system with site-specific DNAzyme activation property. Herein, a highly compact and robust Zn@DDz nanoplatform is constructed by integrating the unimolecular microRNA-responsive DNA-cleaving DNAzyme (DDz) probe with the requisite DNAzyme Zn2+ -ion cofactors, and the amplified intracellular imaging of microRNA via the spatiotemporally programmed disassembly of Zn@DDz nanoparticles is achieved. The multifunctional Zn@DDz nanoplatform is simply composed of a structurally blocked self-hydrolysis DDz probe and the inorganic Zn2+ -ion bridge, with high loading capacity, and can effectively deliver the initially catalytic inert DDz probe and Zn2+ into living cells with enhanced stabilities. Upon their entry into the acidic microenvironment of living cells, the self-sufficient Zn@DDz nanoparticle is disassembled to release DDz probe and simultaneously supply Zn2+ -ion cofactors. Then, endogenous microRNA-21 catalyzes the reconfiguration and activation of DDz for generating the amplified readout signal with multiply guaranteed imaging performance. Thus, this work paves an effective way for promoting DNAzyme-based biosensing systems in living cells, and shows great promise in clinical diagnosis.

Ivermectin as a potential therapeutic strategy for glioma

Ivermectin (IVM), a semi-synthetic macrolide parasiticide, has demonstrated considerable effectiveness in combating internal and external parasites, particularly nematodes and arthropods. Its remarkable ability to control parasites has earned it significant recognition, culminating in Satoshi Omura and William C. Campbell's receipt of the 2015 Nobel Prize in Physiology or Medicine for their contributions to the development of IVM. In recent years, investigations have revealed that IVM possesses antitumor properties. It can suppress the growth of various cancer cells, including glioma, through a multitude of mechanisms such as selective targeting of tumor-specific proteins, inducing programmed cell death, and modulation of tumor-related signaling pathways. Hence, IVM holds tremendous potential as a novel anticancer drug. This review seeks to provide an overview of the underlying mechanisms that enable IVM's capacity to suppress glioma. Furthermore, it aims to elucidate the challenges and prospects associated with utilizing IVM as a new anticancer agent.

Evaluation of Diagnostic Significance of Salivary miRNA-184 and miRNA-21 in Oral Squamous Cell Carcinoma and Oral Potentially Malignant Disorders

BACKGROUND

Altered levels of miRNAs might affect the pathogenesis of oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMD). This study evaluated the diagnostic potential of salivary miRNA-21 and miRNA-184 in OSCC and OPMD.

METHODS

We recruited a total of 90 subjects including OSCC, OPMD, and healthy controls. RNA was isolated from the saliva samples of the study subjects. Expression of miRNA-21 and miRNA-184 was analyzed using qRT-PCR. Their levels were compared and the diagnostic cut-off was determined using the ROC curve.

RESULTS

There was a significant increase in miRNA-21 and a decrease in miRNA-184 in OSCC and OPMD as compared to healthy controls (p < 0.001). Levels of salivary miRNA-21 and miRNA-184 can differentiate OSCC and OPMD from controls and premalignant conditions from malignant conditions.

CONCLUSION

Salivary miRNA-21 and miRNA-184 may be beneficial for the early detection of OSCC and OPMD. Also, saliva can be used for detecting neoplastic transformation of oral mucosa since it is non-invasive and easily accessible.

miRNAs in the prognosis of triple-negative breast cancer: A review

Triple-Negative Breast Cancer (TNBC) is a highly aggressive and invasive type of breast cancer (BC) with high mortality rate wherein effective target medicaments are lacking. It is a very heterogeneous group with several subtypes that account for 10-20% of cancer among women globally, being negative for three most important receptors (estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2)), with an early and high recurrence resulting in poor survival rate. Therefore, a more thorough knowledge on carcinogenesis of TNBC is required for the development of personalized treatment options. miRNAs can either promote or suppress tumorigenesis and have been linked to a number of features of cancer progression, including proliferation, metastasis, apoptosis, and epithelial-mesenchymal transition (EMT). Recent miRNA research shows that there is great potential for the development of novel biomarkers as they have emerged as drivers of tumorigenesis and provide opportunities to target various components involved in TNBC, thus helping to solve this difficult-to-treat disease. In this review, we summarize the most relevant miRNAs that play an essential role in TNBC biology. Their role with regard to molecular mechanisms underlying TNBC progression has been discussed, and their potential use as therapeutic or prognostic markers to unravel the intricacy of TNBC based on the pieces of evidence obtained from various works of literature has been briefly addressed.

In Situ Simultaneous Detection of Surface Protein and microRNA in Clustered Extracellular Vesicles from Cancer Cell Lines Using Flow Cytometry

Extracellular vesicles (EVs) are becoming increasingly important in liquid biopsy for cancer because they contain multiple biomarkers, including proteins and RNAs, and circulate throughout the body. Cancer cell-derived EVs are highly heterogeneous, and multiplexed biomarker detection techniques are required to improve the accuracy of diagnosis. In addition, in situ EV biomarker detection increases the efficiency of the detection process because EVs are difficult to handle. In this study, in situ simultaneous detection of EV surface proteins, programmed cell death-ligand 1 (PD-L1), and internal miRNA-21 (miR-21) analyzed by conventional flow cytometry was developed for a breast cancer liquid biopsy. However, the majority of EVs were not recognized by flow cytometry for biomarker detection because the size of EVs was below the detectable size range of the flow cytometer. To solve this problem, the formation of EV clusters was induced by 1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE)-polyethylene glycol-DSPE during biomarker detection. Consequently, both PD-L1 and miR-21 detection signals from cancer cell-derived EVs were drastically increased, making them distinguishable from normal cell-derived EVs. The in situ simultaneous cancer biomarker detection from EV clusters analyzed by flow cytometry contributes to an increase in the sensitivity and accuracy of the EV-based liquid biopsy for cancer.

Circulating exosomal miRNAs as a promising diagnostic biomarker in cancer

Cancer belongs to multifactorial diseases characterized by uncontrolled growth and proliferation of abnormal cells. Breast cancer, non-small cell lung cancer, and colorectal cancer are the most frequently diagnosed malignancies with a high mortality rate. These carcinomas typically contain multiple genetically distinct subpopulations of tumor cells leading to tumor heterogeneity, which promotes the aggressiveness of the disease. Early diagnosis is necessary to increase patient progression-free survival. Particularly, miRNAs present in exosomes derived from tumors represent potential biomarkers suitable for early cancer diagnosis. Identification of miRNAs by liquid biopsy enables a personalized approach with the subsequent better clinical management of patients. This review article highlights the potential of circulating exosomal miRNAs in early breast, non-small cell lung, and colorectal cancer diagnosis.

Tumor targeting and therapeutic assessments of RNA nanoparticles carrying α9-nAChR aptamer and anti-miR-21 in triple-negative breast cancers

Triple-negative breast cancer (TNBC) is highly aggressive with a poor prognosis because of a lack of cell markers as drug targets. α9-Nicotinic acetylcholine receptor (nAChR) is expressed abundantly in TNBC; thus, it is a valuable biomarker for TNBC detection and treatment. In this study, we utilized thermodynamically stable three-way junction (3WJ) packaging RNA (pRNA) as the core to construct RNA nanoparticles with an α9-nAChR RNA aptamer as a targeting ligand and an anti-microRNA-21 (miR-21) as a therapeutic module. We compared the configuration of the two RNA nanoparticles and found that 3WJ-B-α9-nAChR-aptamer fluorescent RNA nanoparticles (3WJ-B-α9-apt-Alexa) exhibited better specificity for α9-nAChR in TNBC cells compared with 3WJ-C-α9-nAChR. Furthermore, 3WJ-B-α9-apt-Alexa bound more efficiently to TNBC patient-derived xenograft (PDX) tumors than 3WJ fluorescent RNA nanoparticles (3WJ-Alexa) with little or no accumulation in healthy organs after systemic injection in mice. Moreover, 3WJ-B-α9-nAChR-aptamer RNA nanoparticles carrying anti-miR-21 (3WJ-B-α9-apt-anti-miR-21) significantly suppressed TNBC-PDX tumor growth and induced cell apoptosis because of reduced miR-21 gene expression and upregulated the phosphatase and tensin homolog (PTEN) and programmed cell death 4 (PDCD4) proteins. In addition, no pathological changes were detected upon toxicity examination of treated mice. In conclusion, the 3WJ-B-α9-nAChR-aptamer RNA nanoparticles established in this study efficiently deliver therapeutic anti-miR-21, indicating their potential as a novel TNBC therapy.

Deciphering the Functional Status of Breast Cancers through the Analysis of Their Extracellular Vesicles

Breast cancer (BC) accounts for the highest incidence of tumor-related mortality among women worldwide, justifying the growing search for molecular tools for the early diagnosis and follow-up of BC patients under treatment. Circulating extracellular vesicles (EVs) are membranous nanocompartments produced by all human cells, including tumor cells. Since minimally invasive methods collect EVs, which represent reservoirs of signals for cell communication, these particles have attracted the interest of many researchers aiming to improve BC screening and treatment. Here, we analyzed the cargoes of BC-derived EVs, both proteins and nucleic acids, which yielded a comprehensive list of potential markers divided into four distinct categories, namely, (i) modulation of aggressiveness and growth; (ii) preparation of the pre-metastatic niche; (iii) epithelial-to-mesenchymal transition; and (iv) drug resistance phenotype, further classified according to their specificity and sensitivity as vesicular BC biomarkers. We discuss the therapeutic potential of and barriers to the clinical implementation of EV-based tests, including the heterogeneity of EVs and the available technologies for analyzing their content, to present a consistent, reproducible, and affordable set of markers for further evaluation.

In silico analysis and experimental validation shows negative correlation between miR-1183 and cell cycle progression gene 1 expression in colorectal cancer

MicroRNAs (miRNAs) are small noncoding RNAs that post-transcriptionally regulate gene expression by binding to the 3' untranslated regions (UTR) of target genes. Aberrant expression of miRNAs can lead to disease, including cancer. Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths worldwide. Among several factors, differential expression of miRNA can have serious consequences on disease progression. This study was designed to computationally identify and experimentally verify strong miRNA candidates that could influence CRC progression. In silico analysis of publicly available gene expression microarray datasets revealed significant upregulation of miR-1183 in CRC. Comparison of mRNA microarray expression data with predicted miR-1183 targets led to the identification of cell cycle progression gene 1 (CCPG1) as strong, negatively correlated miR-1183 target. Expression analysis by means of quantitative PCR validated the inverse correlation between miR-1183 and CCPG1 in colorectal cancer tissues. CCPG1 indirectly modulates the cell cycle by interacting with the PH/DH domain of Dbs (Rho-specific guanine nucleotide exchange factor). Interestingly, the computational analysis also showed that miR-1183 is upregulated in liver and gastric cancer. This finding is notable as the liver and stomach are the primary metastatic sites for colorectal cancer and hepatocellular carcinoma respectively. This novel finding highlights the broader implications of miR-1183 dysregulation beyond primary CRC, potentially serving as a valuable prognostic marker and a therapeutic target for both primary and metastatic CRC.

MicroRNAs as biomarkers for early diagnosis, targeting and prognosis of prostate cancer

Globally, prostate cancer (PC) is leading cause of cancer-related mortality in men worldwide. Despite significant advances in the treatment and management of this disease, the cure rates for PC remains low, largely due to late detection. PC detection is mostly reliant on prostate-specific antigen (PSA) and digital rectal examination (DRE); however, due to the low positive predictive value of current diagnostics, there is an urgent need to identify new accurate biomarkers. Recent studies support the biological role of microRNAs (miRNAs) in the initiation and progression of PC, as well as their potential as novel biomarkers for patients' diagnosis, prognosis, and disease relapse. In the advanced stages, cancer-cell-derived small extracellular vesicles (SEVs) may constitute a significant part of circulating vesicles and cause detectable changes in the plasma vesicular miRNA profile. Recent computational model for the identification of miRNA biomarkers discussed. In addition, accumulating evidence indicates that miRNAs can be utilized to target PC cells. In this article, the current understanding of the role of microRNAs and exosomes in the pathogenesis and their significance in PC prognosis, early diagnosis, chemoresistance, and treatment are reviewed.

Connecting the dots in the associations between diet, obesity, cancer, and microRNAs

The prevalence of obesity has reached pandemic levels worldwide, leading to a lower quality of life and higher health costs. Obesity is a major risk factor for noncommunicable diseases, including cancer, although obesity is one of the major preventable causes of cancer. Lifestyle factors, such as dietary quality and patterns, are also closely related to the onset and development of obesity and cancer. However, the mechanisms underlying the complex association between diet, obesity, and cancer remain unclear. In the past few decades, microRNAs (miRNAs), a class of small non-coding RNAs, have been demonstrated to play critical roles in biological processes such as cell differentiation, proliferation, and metabolism, highlighting their importance in disease development and suppression and as therapeutic targets. miRNA expression levels can be modulated by diet and are involved in cancer and obesity-related diseases. Circulating miRNAs can also mediate cell-to-cell communications. These multiple aspects of miRNAs present challenges in understanding and integrating their mechanism of action. Here, we introduce a general consideration of the associations between diet, obesity, and cancer and review the current knowledge of the molecular functions of miRNA in each context. A comprehensive understanding of the interplay between diet, obesity, and cancer could be valuable for the development of effective preventive and therapeutic strategies in future.

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.

Geraniol suppresses tumour growth and enhances chemosensitivity of 5-fluorouracil on breast carcinoma in mice: involvement of miR-21/PTEN signalling

OBJECTIVES

Breast cancer is the most diagnosed cancer in females worldwide. Phytochemicals are among the recent compelling approaches showing anticancer activity. Geraniol is a monoterpenoid showing anti-tumoral potential in cell lines. However, its exact mechanism in breast cancer has not been elucidated. In addition, the possible chemosenstizing effect of geraniol when combined with chemotherapeutic drugs in breast carcinoma has not been previously addressed.

METHODS

Therefore, the aim of the current work is to investigate the potential therapeutic as well as chemosensitizing effects of geraniol on breast carcinoma induced in mice through examination of tumour biomarkers and histopathology profile.

KEY FINDINGS

Results showed a prominent suppression of tumour growth following geraniol treatment. This was accompanied with miR-21 downregulation that subsequently upregulated PTEN and suppressed mTOR levels. Geraniol was also able to activate apoptosis and inhibit autophagy. Histopathological examination revealed high necrosis areas separating malignant cells in the geraniol-treated group. Combined geraniol and 5-fluorouracil treatment induced more than 82% inhibition of tumour rate, surpassing the effect of each drug alone.

CONCLUSIONS

It can be concluded that geraniol could represent a promising avenue for breast cancer treatment as well as a potential sensitizing agent when combined with chemotherapeutic drugs.

Breast Cancer Therapeutics and Hippo Signaling Pathway: Novel MicroRNA-Gene-Protein Interaction Networks

The Hippo signaling pathway is a master regulator of development, cell proliferation, and apoptosis in particular, and it plays an important role in tissue regeneration, controlling organ size, and cancer suppression. Dysregulation of the Hippo signaling pathway has been implicated in breast cancer, a highly prevalent cancer affecting 1 out of every 15 women worldwide. While the Hippo signaling pathway inhibitors are available, they are suboptimal, for example, due to chemoresistance, mutation, and signal leakage. Inadequate knowledge about the Hippo pathway connections and their regulators limits our ability to uncover novel molecular targets for drug development. We report here novel microRNA (miRNA)-gene and protein-protein interaction networks in the Hippo signaling pathway. We employed the GSE miRNA dataset for the present study. The GSE57897 dataset was normalized and searched for differentially expressed miRNAs, and their targets were searched using the miRWalk2.0 tool. From the upregulated miRNAs, we observed that the hsa-miR-205-5p forms the biggest cluster and targets four genes involved in the Hippo signaling pathway. Interestingly, we found a novel connection between two Hippo signaling pathway proteins, angiomotin (AMOT) and mothers against decapentaplegic homolog 4 (SMAD4). From the downregulated miRNAs, hsa-miR-16-5p, hsa-miR-7g-5p, hsa-miR-141-3p, hsa-miR-103a-3p, hsa-miR-21-5p, and hsa-miR-200c-3p, target genes were present in the pathway. We found that PTEN, EP300, and BTRC were important cancer-inhibiting proteins, form hubs, and their genes interact with downregulating miRNAs. We suggest that targeting proteins from these newly unraveled networks in the Hippo signaling pathway and further research on the interaction of hub-forming cancer-inhibiting proteins can open up new avenues for next-generation breast cancer therapeutics.