The role of extracellular vesicles in cancer

Progress in the application of mesenchymal stem cells to attenuate apoptosis in diabetic kidney disease

Diabetic kidney disease (DKD) has a high incidence and mortality rate and lacks effective preventive and therapeutic methods. Apoptosis is one of the main reasons for the occurrence and development of DKD. Mesenchymal stem cells (MSCs) have shown great promise in tissue regeneration for DKD treatment and have protective effects against DKD, including decreased blood glucose and urinary protein levels and improved renal function. MSCs can directly differentiate into kidney cells or act via paracrine mechanisms to reduce apoptosis in DKD by modulating signaling pathways. MSC-derived extracellular vesicles (MSC-EVs) mitigate apoptosis and DKD-related symptoms by transferring miRNAs to target cells or organs. However, studies on the regulatory mechanisms of MSCs and MSC-EVs in apoptosis in DKD are insufficient. This review comprehensively examines the mechanisms of apoptosis in DKD and research progress regarding the roles of MSCs and MSC-EVs in the disease process.

Extracellular vesicles in uveal melanoma - Biological roles and diagnostic value

Uveal melanoma (UM), which originates from the uveal tract of the eye, is the most common and aggressive intraocular cancer in adults. The detection of genetic markers is crucial for an accurate diagnosis, but this requires tumor biopsies that can be challenging to obtain. Extracellular vesicles (EVs) have emerged as potential biomarkers for UM due to their presence in biological fluids and their ability to carry disease-related biomolecules such as proteins and nucleic acids. Increasing evidence indicates that EVs released from UM cells play crucial roles in UM development, including cancer progression, pre-metastatic niche formation, and metastasis. Moreover, many studies have demonstrated that UM-derived EVs carry proteins and microRNAs that might be used as biomarkers. This review explores the role of EVs in UM, focusing on their biological functions and their potential as diagnostic and prognostic biomarkers of UM. Additionally, current challenges to the use of UM-derived EVs in clinical translation were identified, as well as perspectives and future directions in the field.

Neutrophil- and Endothelial Cell-Derived Extracellular Microvesicles Are Promising Putative Biomarkers for Breast Cancer Diagnosis

Introduction: Breast cancer (BC) is a disease that affects about 2.2 million people worldwide. The prognosis and treatment of these patients depend on clinical and histopathologic staging, in which more aggressive cancers need a less conservative therapeutic approach. Previous studies showed that patients with BC have an increased frequency of systemic microvesicles (MVs) that are associated with invasion, progression, and metastasis, which can be used in liquid biopsy to predict the therapeutic response in individualized treatment. Objective: This study proposes the development of a minimally invasive BC diagnostic panel and follow-up biomarkers as a complementary method to screen patients. Methods: The quantification of circulating MVs in 48 healthy women and 100 BC patients who attended the Mário Penna Institute between 2019 and 2022 was performed by flow cytometry. In addition, the MVs of BC patients were analyzed before treatment and 6, 12, and 24 months post-treatment. Machine learning approaches were employed to determine the performance of MVs to identify BC and to propose BC classifier algorithms. Results: Patients with BC had more neutrophil- and endothelial cell-derived MVs than controls before treatment. After treatment, all MV populations were decreased compared to pre-treatment, but leukocyte- and erythrocyte-derived MVs were increased at 12 months after treatment, before decreasing again at 24 months. Conclusions: Performance analyses and machine learning approaches pointed out that MVs from neutrophils and endothelial cells are the best candidates for BC diagnostic biomarkers. Neutrophil- and endothelial cell-derived MVs are putative candidates for BC biomarkers to be employed as screening tests for BC diagnosis.

Choline kinase alpha regulates autophagy-associated exosome release to promote glioma cell progression

Glioma is the most common primary intracranial malignant tumor in adults, with a poor prognosis. Exosomes released by tumor cells play a crucial role in tumor development, metastasis, angiogenesis, and other biological processes. Despite this significance, the precise molecular mechanisms governing exosome secretion and their impact on tumor progression remain incompletely understood. While Choline Kinase Alpha (CHKA) has been implicated in promoting various types of tumors, its specific role in glioma pathogenesis remains unclear. Our study initially demonstrates that CHKA enhances the proliferation, migration, and invasion abilities of glioma cells. Interestingly, CHKA also stimulates the release of exosomes from glioma cells. Mechanistically, reduced CHKA expression hampers exosome secretion by elevating autophagy levels in gliomas, whereas counteracting the autophagy elevation resulting from CHKA downregulation restores the release of exosomes. Notably, exosomes derived from glioma cells with normal CHKA expression exhibit a greater capacity to promote glioma progression compared to those derived from cells with low CHKA expression. Overall, our findings suggest that CHKA modulates exosome secretion via an autophagy-dependent pathway, thereby facilitating the proliferation, migration, and invasion of glioma cells.