The Role of miRNAs in the Prognosis of Triple-Negative Breast Cancer: A Systematic Review and Meta-Analysis

miRNA signatures affecting the survival outcome in distant metastasis of triple-negative breast cancer

Triple-negative breast cancer (TNBC) constitutes for 10-15% of all breast cancer cases. Tumor heterogeneity, high invasiveness, distant metastasis, lack of estrogen receptors, progesterone receptors, and human epidermal growth factor receptor 2 expression contribute to TNBC associated with poor overall survival outcomes amongst diseased individuals. The disparity in clinico-pathological and metastatic patterns to distant sites has substantially enhanced the incidences of tumor recurrence. Survival outcomes amongst metastatic TNBC patients are worse in comparison to non-metastatic TNBC counterparts. MicroRNAs (miRNAs) have emerged as significant drivers to function either as oncogene or tumor suppressors by exerting modulating effects on the expression of target genes in the TNBC tumor microenvironment. The pleiotropic nature of miRNAs expands their preclinical and clinical utility in combating both metastatic and non-metastatic TNBC cases and thereby improves their survival outcomes. The present review article aims to highlight the varying survival outcomes in metastatic and non-metastatic TNBC cases. The present review article emphasizes the therapeutic and prognostic potential of miRNAs in TNBC to improve survival outcomes by retarding distant metastasis to lung, bone, brain, and lymph nodes.

Multifaceted role of microRNA-301a in human cancer: from biomarker potential to therapeutic targeting

With the growing data on microRNA (miRNA) expression in tissues and circulation, there is increasing evidence for the potential of microRNAs to serve as biomarkers in cancer diagnosis and prognosis, as well as novel therapeutic targets. The expression level of miRNA-301a (miR-301a) is altered in a wide range of human tumor types, and numerous studies have revealed the roles of miR-301a in tumorigenesis and tumor progression. Herein, we comprehensively summarize, compare, and contrast the research advancements on the role of miR-301a in different cancers. Differential expression patterns of miR-301a in tissues and biofluids are implicated in cancer diagnosis, treatment response, and prognosis. MiR-301a modulates the expression of multiple genes, other noncoding RNAs, and signaling cascade via direct or indirect regulation in human cancer proliferation, migration, invasion, angiogenesis, and radio- or chemotherapy resistance. Cancer cell-associated miR-301a affects the tumor microenvironment through the alteration of immune function and cancer metabolism. These findings highlight the functional roles, clinical implications, and therapeutic relevance of miR-301a in various human cancers.

MIR27A rs895819 CC Genotype Severely Reduces miR-27a Plasma Expression Levels

Background/Objectives:MIR27A rs895819 polymorphism has emerged as a potential additional pharmacogenomic marker of fluoropyrimidine response. Current evidence on its potential effect on miR-27a expression, which represses DPD activity, leading to DPD deficiency and increased fluoropyrimidine-associated toxicity risk, is scarce and inconsistent. We have analyzed the effect of MIR27A rs895819 polymorphism on miR-27a-3p plasma expression levels under different models of inheritance to contribute further evidence on its plausible biological role in miR-27a expression. Methods: A total of 59 individuals with no medical history of cancer were included in this study. MIR27A rs895819 genotyping and miR-27a-3p expression were analyzed by using predesigned TaqMan assays. Results: The frequency of TT, TC, and CC genotypes was present at a prevalence of 50.8%, 44.1%, and 5.1%, respectively. Individuals carrying the CC genotype presented with decreased miR-27a-3p expression (0.422 fold-change versus TT, p = 0.041; 0.461 fold-change versus TC, p = 0.064), whereas no differences were present between TT and TC individuals (1.092 fold-change, p = 0.718). miR-27a-3p expression was decreased in CC individuals under a recessive model of inheritance (0.440 fold-change, p = 0.047). No differences were found in dominant (TT vs. TC+CC, 0.845 fold-change, p = 0.471) or over dominant (TT+CC vs. TC, 0.990 fold-change, p = 0.996) models of inheritance. Conclusions:MIR27A rs895819CC genotype leads to severely reduced miR-27a-3p expression in plasma. Further study of this association is warranted in cancer patients to apply MIR27A genotyping in therapeutics to identify fluoropyrimidine-treated patients who are at a decreased risk of experiencing fluoropyrimidine-induced severe toxicity.

Impact of microRNA variants on PI3K/AKT signaling in triple-negative breast cancer: comprehensive review

Breast cancer (BC) is a significant cause of cancer-related mortality, and triple-negative breast cancer (TNBC) is a particularly aggressive subtype associated with high mortality rates, especially among younger females. TNBC poses a considerable clinical challenge due to its aggressive tumor behavior and limited therapeutic options. Aberrations within the PI3K/AKT pathway are prevalent in TNBC and correlate with increased therapeutic intervention resistance and poor outcomes. MicroRNAs (miRs) have emerged as crucial PI3K/AKT pathway regulators influencing various cellular processes involved in TNBC pathogenesis. The levels of miRs, including miR-193, miR-4649-5p, and miR-449a, undergo notable changes in TNBC tumor tissues, emphasizing their significance in cancer biology. This review explored the intricate interplay between miR variants and PI3K/AKT signaling in TNBC. The review focused on the molecular mechanisms underlying miR-mediated dysregulation of this pathway and highlighted specific miRs and their targets. In addition, we explore the clinical implications of miR dysregulation in TNBC, particularly its correlation with TNBC prognosis and therapeutic resistance. Elucidating the roles of miRs in modulating the PI3K/AKT signaling pathway will enhance our understanding of TNBC biology and unveil potential therapeutic targets. This comprehensive review aims to discuss current knowledge and open promising avenues for future research, ultimately facilitating the development of precise and effective treatments for patients with TNBC.

Management of triple-negative breast cancer by natural compounds through different mechanistic pathways

Triple-negative breast cancer (TNBC) is the most severe form of breast cancer, characterized by the loss of estrogen, progesterone, and human epidermal growth factor receptors. It is caused by various genetic and epigenetic factors, resulting in poor prognosis. Epigenetic changes, such as DNA methylation and histone modification, are the leading mechanisms responsible for TNBC progression and metastasis. This review comprehensively covers the various subtypes of TNBC and their epigenetic causes. In addition, the genetic association of TNBC with all significant genes and signaling pathways linked to the progression of this form of cancer has been enlisted. Furthermore, the possible uses of natural compounds through different mechanistic pathways have also been discussed in detail for the successful management of TNBC.

MicroRNA as a promising molecular biomarker in the diagnosis of breast cancer

Introduction: Breast cancer represents the most prevalent malignancy among women. Recent advancements in translational research have focused on the identification of novel biomarkers capable of providing valuable insights into patient outcomes. Furthermore, comprehensive investigations aimed at discovering novel miRNAs, unraveling their biological functions, and deciphering their target genes have significantly contributed to our understanding of the roles miRNAs play in tumorigenesis. Consequently, these investigations have facilitated the way for the development of miRNA-based approaches for breast cancer prognosis, diagnosis, and treatment. However, conducting a more extensive array of studies, particularly among diverse ethnic groups, is imperative to expand the scope of research and validate the significance of miRNAs. This study aimed to assess the expression patterns of circulating miRNAs in plasma as a prospective biomarker for breast cancer patients within a population primarily consisting of individuals from Black, Indigenous, and People of Color (BIPOC) communities. Methods: We evaluated 49 patients with breast cancer compared to 44 healthy women. Results and discussion: All miRNAs analyzed in the plasma of patients with breast cancer were downregulated. ROC curve analysis of miR-21 (AUC = 0.798, 95% CI: 0.682-0.914, p <0.0001), miR-1 (AUC = 0.742, 95% CI: 0.576-0.909, p = 0.004), miR-16 (AUC = 0.721, 95% CI: 0.581-0.861, p = 0.002) and miR-195 (AUC = 0.672, 95% CI: 0.553-0.792, p = 0.004) showed better diagnostic accuracy in discrimination of breast cancer patients in comparison with healthy women. miR-210, miR-21 showed the highest specificities values (97.3%, 94.1%, respectively). Following, miR-10b and miR-195 showed the highest sensitivity values (89.3%, and 77.8%, respectively). The panel with a combination of four miRNAs (miR-195 + miR-210 + miR-21 + miR-16) had an AUC of 0.898 (0.765-0.970), a sensitivity of 71.4%, and a specificity of 100.0%. Collectively, our results highlight the miRNA combination in panels drastically improves the results and showed high accuracy for the diagnosis of breast cancer displaying good sensitivity and specificity.

Investigation of key miRNAs and Target-mRNA in Kaposi's sarcoma using bioinformatic methods

Kaposi's sarcoma (KS) is the second most common tumor in human immunodeficiency virus (HIV) infected patients worldwide. While many miRNAs have been confirmed to be involved in KS biological processes, no relevant studies have combined miRNA and mRNA expression profiles using KS patient tissue biopsies. In this study, we performed transcriptome sequencing on tumor and normal tissues from four KS patients and identified differentially expressed mRNA and miRNA, further performed target gene prediction and enrichment analysis. 19,551 target-mRNAs were identified by predicting 106 miRNAs, with 553 overlapping with 571 significantly differentially expressed mRNAs. Enrichment analysis showed significant involvement of the Ubiquitin-mediated proteolysis pathway. Additionally, the miRNA-mRNA interaction network was established, and the topological score of Cytohubba's algorithm was calculated for comparison with three other datasets. The Mutual Clustering Coefficient (MCC) scoring ranking placed ZBTB34, NFIB, and RORA as the top three mRNAs, while hsa-miR-16-5p, hsa-miR-27a-3p, hsa-miR-340-5p, hsa-miR-182-5p, and hsa-miR-186-5p ranked as the top five miRNAs. Hsa-miR-101-3p is the only miRNA that appears both in the top 10 MCC scores and at the intersection of the other two datasets. Finally, qRT-PCR was used to validate the findings at the cellular level. In summary, the miRNA analysis results indicated that hsa-miR-101-3p could be used as a potential diagnostic or therapeutic marker in future studies. Moreover, the mRNA analysis results suggested that the histone binding pathways involved in mRNAs and ubiquitin-related biological processes were closely associated with KS and could serve as promising biomarkers for the diagnosis and treatment of this disease.

MicroRNAs as Molecular Biomarkers for the Characterization of Basal-like Breast Tumor Subtype

Breast cancer is a heterogeneous disease highlighted by the presence of multiple tumor variants and the basal-like breast cancer (BLBC) is considered to be the most aggressive variant with limited therapeutics and a poor prognosis. Though the absence of detectable protein and hormonal receptors as biomarkers hinders early detection, the integration of genomic and transcriptomic profiling led to the identification of additional variants in BLBC. The high-throughput analysis of tissue-specific micro-ribonucleic acids (microRNAs/miRNAs) that are deemed to have a significant role in the development of breast cancer also displayed distinct expression profiles in each subtype of breast cancer and thus emerged to be a robust approach for the precise characterization of the BLBC subtypes. The classification schematic of breast cancer is still a fluid entity that continues to evolve alongside technological advancement, and the transcriptomic profiling of tissue-specific microRNAs is projected to aid in the substratification and diagnosis of the BLBC tumor subtype. In this review, we summarize the current knowledge on breast tumor classification, aim to collect comprehensive evidence based on the microRNA expression profiles, and explore their potential as prospective biomarkers of BLBC.

Prospectives of mirna gene signaling pathway in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is one of the destructive breast cancer subtypes which cannot be treated by current therapies, which is characterized by the lack of estrogen (ER), Progesterone (PR), and Human epidermal receptor (HER2). The treatment for this chemotherapy or radiotherapy and surgery are such treatments and also novel biomarkers or treatment targets can quickly require to improve the outcome of the disease. MicroRNAs are the most popular and offer prospects for TNBC diagnosis and therapy. Some of the miRNAs implicated in THBCs are miR-17-5p, miR-221-3p, miR-26a, miR-136-5p, miR-1296, miR-145, miR-4306, miR-508-5p, miR-448, miR-539, miR-211-5p and miR-218. Potential MiRNAs and their signaling pathways that can be utilized for the diagnosis of TNBC are miR-155, miR-182-5p, miR-9-1-5p, miR-200b, miR-200a, miR-429, miR-195, miR-145-5p, miR-506, and miR-22-3p. miRNAs with known functions as tumor suppressors include miR-1-3p, miR-133a-3p, miR-655, miR-206, miR-136, miR-770, miR-148a, miR-197-3p, miR-137, and miR-127-3p. Analysis of genetic biomarkers, such as miRNAs in TNBC, upholds the pertinence in the diagnosis of the disease. The aim of the review was to clarify the different types of miRNAs characters in TNBC. Recent reports suggest an important role of miRNAs in tumor metastasis. We review here the important miRNAs and their signaling pathways implicated in the oncogenesis, progression, and metastasis of TNBCs.

Unlocking the Potential of Circulating miRNAs in the Breast Cancer Neoadjuvant Setting: A Systematic Review and Meta-Analysis

The potential role of circulating microRNAs (miRNAs) as biomarkers in breast cancer (BC) management has been widely reported. However, the numerous discrepancies between studies in this regard hinders the implementation of circulating miRNAs in routine clinical practice. In the context of BC patients undergoing neoadjuvant chemotherapy (NAC), the possibility of predicting NAC response may lead to prognostic improvements by individualizing post-neoadjuvant therapy. In this context, the present meta-analysis aims to clarify circulating miRNAs' predictive role with respect to NAC response among BC patients. We conducted a comprehensive literature search on five medical databases until 16 February 2023. We pooled the effect sizes of each study by applying a random-effects model. Cochran's Q test (p-level of significance set at 0.05) scores and I² values were assessed to determine between-study heterogeneity. The PROBAST (Prediction Model Risk of Bias Assessment Tool) tool was used to evaluate the selected studies' risk of bias. Overall, our findings support the hypothesis that circulating miRNAs, specifically miR-21-5p and miR-155-5p, may act as predictive biomarkers in the neoadjuvant setting among BC patients. However, due to the limited number of studies included in this meta-analysis and the high degrees of clinical and statistical heterogeneity, further research is required to confirm the predictive power of circulating miR-21-5p and miR-155-5p.

Tumor Suppressive Role of MicroRNAs in Triple Negative Breast Cancer

Triple-negative breast cancers are highly aggressive, a heterogeneous form of breast cancer with a high re-occurrence rate that further lacks an efficient treatment strategy and prognostic marker. The tumor microenvironment of the disease comprises cancer-associated fibroblasts, cancer stem cells, immunological molecules, epithelial-mesenchymal transition, and a metastatic microenvironment that contributes to disease progression and metastasis to distant sites. Emerging evidence indicated that miRNA clusters would be of clinical utility as they exert an oncogenic or tumor suppressor role in TNBC. The present review article aims to highlight the therapeutic significance of miRNA in targeting the above-mentioned signaling cascades and modulating the intracellular crosstalk in the tumor microenvironment of TNBC. Prognostic implications of miRNAs to depict disease-free survival, distant metastasis-free survival, relapse-free survival, and overall survival outcome were also unveiled.