Exosomes in triple negative breast cancer: From bench to bedside

Next-generation biomarkers for prognostic and potential therapeutic enhancement in Triple negative breast cancer

Triple-negative breast carcinoma (TNBC) is one of the most challenging subtypes of breast carcinoma and it has very limited therapeutic options as it is highly aggressive. The prognostic biomarkers are crucial for early diagnosis of the tumor, it also helps in anticipating the trajectory of the illness and optimizing the therapy options. Several therapeutic biomarkers are being used. Among them, the next-generation biomarkers that include Circulating tumor (ct) DNA, glycogen, lipid, and exosome biomarkers provide intriguing opportunities for enhancing the prognosis of TNBC. Lipid and glycogen biomarkers serve as essential details on the development of the tumor along with the efficacy of the treatment, as it exhibits metabolic alteration linked to TNBC. Several types of biomarkers have predictive abilities in TNBC. Elevated levels are associated with worse outcomes. ctDNA being a noninvasive biomarker reveals the genetic composition of the tumor, as well as helps to monitor the progression of the disease. Traditional therapies are ineffective in TNBC due to a lack of receptors, targeted drug delivery provides a tailored approach to overcome drug resistance and site-specific action by minimizing the side effects in TNBC treatment. This enhances therapeutic outcomes against the aggressive nature of breast cancer. This paper includes all the recent biomarkers which has been researched so far in TNBC and the state of art for TNBC which is explored.

Exploring the interplay between triple-negative breast cancer stem cells and tumor microenvironment for effective therapeutic strategies

Triple-negative breast cancer (TNBC) is a highly aggressive and metastatic malignancy with poor treatment outcomes. The interaction between the tumor microenvironment (TME) and breast cancer stem cells (BCSCs) plays an important role in the development of TNBC. Owing to their ability of self-renewal and multidirectional differentiation, BCSCs maintain tumor growth, drive metastatic colonization, and facilitate the development of drug resistance. TME is the main factor regulating the phenotype and metastasis of BCSCs. Immune cells, cancer-related fibroblasts (CAFs), cytokines, mesenchymal cells, endothelial cells, and extracellular matrix within the TME form a complex communication network, exert highly selective pressure on the tumor, and provide a conducive environment for the formation of BCSC niches. Tumor growth and metastasis can be controlled by targeting the TME to eliminate BCSC niches or targeting BCSCs to modify the TME. These approaches may improve the treatment outcomes and possess great application potential in clinical settings. In this review, we summarized the relationship between BCSCs and the progression and drug resistance of TNBC, especially focusing on the interaction between BCSCs and TME. In addition, we discussed therapeutic strategies that target the TME to inhibit or eliminate BCSCs, providing valuable insights into the clinical treatment of TNBC.

The involvement and application potential of exosomes in breast cancer immunotherapy

Breast cancer has a high incidence and a heightened propensity for metastasis. The absence of precise targets for effective intervention makes it imperative to devise enhanced treatment strategies. Exosomes, characterized by a lipid bilayer and ranging in size from 30 to 150 nm, can be actively released by various cells, including those in tumors. Exosomes derived from distinct subsets of immune cells have been shown to modulate the immune microenvironment within tumors and influence breast cancer progression. In addition, tumor-derived exosomes have been shown to contribute to breast cancer development and progression and may become a new target for breast cancer immunotherapy. Tumor immunotherapy has become an option for managing tumors, and exosomes have become therapeutic vectors that can be used for various pathological conditions. Edited exosomes can be used as nanoscale drug delivery systems for breast cancer therapy, contributing to the remodeling of immunosuppressive tumor microenvironments and influencing the efficacy of immunotherapy. This review discusses the regulatory role of exosomes from different cells in breast cancer and the latest applications of exosomes as nanoscale drug delivery systems and immunotherapeutic agents in breast cancer, showing the development prospects of exosomes in the clinical treatment of breast cancer.

Exosome, a Rising Biomarkers in Liquid Biopsy: Advances of Label-Free and Label Strategy for Diagnosis of Cancer

Cancer is commonly considered as one of the most severe diseases, posing a significant threat to human health and society due to various serious challenges. These challenges include difficulties in accurate diagnosis and a high propensity to form metastasis. Tissue biopsy remains the gold standard for diagnosing and subtyping cancer. However, concerns arise from its invasive nature and the potential risk of metastasis during these complex diagnostic procedures. Meanwhile, liquid biopsy has recently witnessed the rapid advancements with the emergence of three prominent detection biomarkers: circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), and exosomes. Whereas, the very low abundance of CTCs combined with the instability of ctDNA intensify the challenges and decrease the accuracy of these two biomarkers for cancer diagnosis. While exosomes have gained widespread recognition as a promising biomarker in liquid biopsy due to their relatively low-invasive detection method, excellent biostability, rich resources, high abundance, and ability to provide valuable information about cancer. Therefore, it is crucial to systematically summarize recent advancements mainly in exosome-based detection methods for early cancer diagnosis. Specifically, this review will primarily focus on label-based and label-free strategies for detecting cancer using exosomes. We anticipate that this comprehensive analysis will enhance readers' understanding of the significance and value of exosomes in the fields of cancer diagnosis and therapy.

Extracellular vesicles-associated miRNAs in triple-negative breast cancer: from tumor biology to clinical relevance

Breast cancer (BC), a heterogeneous group of diseases, is the most frequent type and the leading cause of cancer-related death among women worldwide. Tumor heterogeneity directly impacts cancer progression and treatment, as evidenced by the patients´ diverse prognosis and treatment responses across the distinct molecular subtypes. Triple-negative breast cancer (TNBC), which accounts for 10-20% of all diagnosed BC cases, is an aggressive BC subtype with a challenging prognosis. Current treatment options include systemic chemotherapy and/or target therapies based on PARP and PD-L1 inhibitors for eligible patients. MicroRNAs (miRNAs) are important regulatory non-coding RNAs (ncRNAs) in TNBC tumorigenesis. These molecules are present both intracellularly and released into biofluids, packaged into extracellular vesicles (EVs). Emerging evidence indicates that EVs-associated miRNAs (EVs-miRNAs), transferred from parental to recipient cells, are key mediators of cell-to-cell communication. Considering their stability and abundance in several biofluids, these molecules may reflect the epigenomic composition of their tumors of origin and contribute to mediate tumorigenesis, similar to their intracellular counterparts. This review provides the current knowledge on EVs-miRNAs in the TNBC subtype, focusing on their role in regulating mRNA targets involved in tumor phenotypes and their clinical relevance as promising biomarkers in liquid biopsies.

Updates on Triple-Negative Breast Cancer in Type 2 Diabetes Mellitus Patients: From Risk Factors to Diagnosis, Biomarkers and Therapy

Triple-negative breast cancer (TNBC) is usually the most malignant and aggressive mammary epithelial tumor characterized by the lack of expression for estrogen receptors and progesterone receptors, and the absence of epidermal growth factor receptor (HER)2 amplification. Corresponding to 15-20% of all breast cancers and well-known by its poor clinical outcome, this negative receptor expression deprives TNBC from targeted therapy and makes its management therapeutically challenging. Type 2 diabetes mellitus (T2DM) is the most common ageing metabolic disorder due to insulin deficiency or resistance resulting in hyperglycemia, hyperinsulinemia, and hyperlipidemia. Due to metabolic and hormonal imbalances, there are many interplays between both chronic disorders leading to increased risk of breast cancer, especially TNBC, diagnosed in T2DM patients. The purpose of this review is to provide up-to-date information related to epidemiology and clinicopathological features, risk factors, diagnosis, biomarkers, and current therapy/clinical trials for TNBC patients with T2DM compared to non-diabetic counterparts. Thus, in-depth investigation of the diabetic complications on TNBC onset, development, and progression and the discovery of biomarkers would improve TNBC management through early diagnosis, tailoring therapy for a better outcome of T2DM patients diagnosed with TNBC.

Non-coding RNAs in renal cell carcinoma: Implications for drug resistance

Renal cell carcinoma (RCC) represents a malignant tumor of the urinary system. Individuals with early-stage RCC could be cured by surgical treatment, but a considerable number of cases of advanced RCC progress to drug resistance. Recently, numerous reports have demonstrated that a variety of non-coding RNAs (ncRNAs) contribute to tumor occurrence and development. ncRNAs can act as oncogenic or tumor suppressor genes to regulate proliferation, migration, drug resistance and other processes in RCC cells through a variety of signaling pathways. Considering the lack of treatment options for advanced RCC after drug resistance, ncRNAs may be a good choice as biomarkers of drug resistance in RCC and targets to overcome drug resistance. In this review, we discussed the effects of ncRNAs on drug resistance in RCC and the great potential of ncRNAs as a biomarker of or a new therapeutic method in RCC.

Exosomal circular RNAs: A chief culprit in cancer chemotherapy resistance

Chemotherapy is one of the primary treatments for malignant tumors. However, the acquired drug resistance hinders clinical efficacy and leads to treatment failure in most patients. Exosomes are cell-derived vesicles with a diameter of 30-150 nm carrying and delivering substances such as DNAs, RNAs, lipids, and proteins for cellular communication in tumor development. Circular RNAs (circRNAs) present covalently closed-loop RNA structures, which regulate tumor cell proliferation, apoptosis, and metastasis by controlling different genes and signaling pathways. CircRNAs are abundant and stably expressed in exosomes. Recent studies have shown that they play critical roles in chemotherapy resistance in various cancers. In this review, we summarized the origin of exosomes and discussed the regulation mechanism of exosomal circRNAs in cancer drug resistance.

The expression of Rab5 and its effect on invasion, migration and exosome secretion in triple negative breast cancer

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer and current therapeutic strategies are limited in their effectiveness. The expressions of Rab5 and the M2 tumor-associated macrophage marker CD163 in tissues were detected by Western blot. The migration and invasion of cells were determined using a Transwell assay. The expressions of the exosome markers were evaluated by Western blot. The polarization of human macrophages (THP-1) was determined by incubation of THP-1 cells with conditioned medium or exosomes collected from MDA-MB-231 cells with indicated transfections or by a coculture system of THP-1 and MDA-MB-231 cells. The M1 and M2 macrophage markers were evaluated by qRT-PCR. The expression of Rab5 in TNBC was significantly higher than that in normal breast tissue. Rab5 expressions in triple-negative and luminal A breast cancer were higher than those in other molecular subtypes. Higher CD163 expression was observed in triple-negative breast cancer and in triple-negative and luminal B subtypes. Rab5 knockdown suppressed but Rab5 overexpression promoted the migration and invasion capacity of MDA-MB-231 cells. The levels of CD63 and CD9 in the medium of Rab5 knockdown cells were lower than those in control cells, whereas higher levels of CD63 and CD9 were observed in Rab5 overexpression cells. Rab5 knockdown decreased the excretion but did not alter the diameter of the exosomes. Knockdown of Rab5 facilitated the anti-tumor polarization of macrophages, which was partially reversed by Rab5 overexpression. Therefore, Rab5 is expected to be a potential therapeutic target for triple-negative breast cancer.

The application of exosomes in the treatment of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a heterogeneous and invasive breast cancer (BC) subtype that is estrogen receptor-negative, progesterone receptor-negative, and human epidermal growth factor receptor 2 (Her2)-negative. So far, the treatment of TNBC is still ineffective due to the lack of well-defined molecular targets. Exosomes are nanosized extracellular vesicles composed of lipid bilayers. They originate from various types of donor cells and release a complex mixture of contents including diverse nucleic acid types (miRNA, LnRNA, siRNA, and DNA) and proteins; after binding to recipient cells the exosomes release their contents that execute their biological functions. Exosomes have been reported to play an important role in the tumorigenesis of TNBC, including tumor initiation, metastasis, angiogenesis, cell proliferation, immune escape, and drug resistance. On the other hand, exosomes can be valuable biomarkers for diagnosis, monitoring, and treatment of TNBC. More interestingly, exosomes can be harnessed as a nanosized drug-delivery system specifically targeting TNBC. In this review, we present the most recent mechanistic findings and clinical applications of exosomes in TNBC therapy, focusing on their use as diagnostic and prognostic biomarkers, nanoscale drug delivery platforms, and immunotherapeutic agents. In addition, the associated challenges and future directions of using exosomes for TNBC treatment will be discussed.

Non-coding RNAs in lung cancer: emerging regulators of angiogenesis

Lung cancer is the second cancer and the leading cause of tumor-related mortality worldwide. Angiogenesis is a crucial hallmark of cancer development and a promising target in lung cancer. However, the anti-angiogenic drugs currently used in the clinic do not achieve long-term efficacy and are accompanied by severe adverse reactions. Therefore, the development of novel anti-angiogenic therapeutic approaches for lung cancer is urgently needed. Non-coding RNAs (ncRNAs) participate in multiple biological processes in cancers, including tumor angiogenesis. Many studies have demonstrated that ncRNAs play crucial roles in tumor angiogenesis. This review discusses the regulatory functions of different ncRNAs in lung cancer angiogenesis, focusing on the downstream targets and signaling pathways regulated by these ncRNAs. Additionally, given the recent trend towards utilizing ncRNAs as cancer therapeutics, we also discuss the tremendous potential applications of ncRNAs as biomarkers or novel anti-angiogenic tools in lung cancer.

Non-coding RNAs and macrophage interaction in tumor progression

The macrophages are abundantly found in TME and their M2 polarization is in favor of tumor malignancy. On the other hand, non-coding RNAs (ncRNAs) can modulate macrophage polarization in TME to affect cancer progression. The miRNAs can dually induce/suppress M2 polarization of macrophages and by affecting various molecular pathways, they modulate tumor progression and therapy response. The lncRNAs can affect miRNAs via sponging and other molecular pathways to modulate macrophage polarization. A few experiments have also examined role of circRNAs in targeting signaling networks and affecting macrophages. The therapeutic targeting of these ncRNAs can mediate TME remodeling and affect macrophage polarization. Furthermore, exosomal ncRNAs derived from tumor cells or macrophages can modulate polarization and TME remodeling. Suppressing biogenesis and secretion of exosomes can inhibit ncRNA-mediated M2 polarization of macrophages and prevent tumor progression. The ncRNAs, especially exosomal ncRNAs can be considered as non-invasive biomarkers for tumor diagnosis.