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Resident macrophages are tissue-specific innate immune cells acting as sentinels, constantly patrolling their assigned tissue to maintain homeostasis, and quickly responding to pathogenic invaders or molecular danger signals molecules when necessary. Adenosine triphosphate (ATP), when released to the extracellular medium, acts as a danger signal through specific purinergic receptors. Interaction of ATP with the purinergic receptor P2X7 activates macrophages and microglial cells in different pathological conditions, triggering inflammation. The highly expressed P2X7 receptor in these cells induces cell membrane permeabilization, inflammasome activation, cell death, and the production of inflammatory mediators, including cytokines and nitrogen and oxygen-reactive species. This review explores the techniques to evaluate the functional and molecular aspects of the P2X7 receptor, particularly in macrophages and microglial cells. Polymerase chain reaction (PCR), Western blotting, and immunocytochemistry or immunohistochemistry are essential for assessing gene and protein expression in these cell types. Evaluation of P2X7 receptor function involves the use of ATP and selective agonists and antagonists and diverse techniques, including electrophysiology, intracellular calcium measurements, ethidium bromide uptake, and propidium iodide cell viability assays. These techniques are crucial for studying the role of P2X7 receptors in immune responses, neuroinflammation, and various pathological conditions. Therefore, a comprehensive understanding of the functional and molecular aspects of the P2X7 receptor in macrophages and microglia is vital for unraveling its involvement in immune modulation and its potential as a therapeutic target. The methodologies presented and discussed herein offer valuable tools for researchers investigating the complexities of P2X7 receptor signaling in innate immune cells in health and disease., Competing Interests: Declaration of competing interest The authors declare no competing or financial interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Introduction: Search for new clinical biomarkers targets in prostate cancer (PC) is urgent. Telomeres might be one of these targets. Telomeres are the extremities of linear chromosomes, essential for genome stability and control of cell divisions. Telomere homeostasis relies on the proper functioning of shelterin and CST complexes. Telomeric dysfunction and abnormal expression of its components are reported in most cancers and are associated with PC. Despite this, there are only a few studies about the expression of the main telomere complexes and their relationship with PC progression. We aimed to evaluate the role of shelterin (POT1, TRF2, TPP1, TIN2, and RAP1) and CST (CTC1, STN1, and TEN1) genes and telomere length in the progression of PC., Methods: We evaluated genetic alterations of shelterin and CST by bioinformatics in samples of localized (n = 499) and metastatic castration-resistant PC (n = 444). We also analyzed the expression of the genes using TCGA (localized PC n = 497 and control n = 152) and experimental approaches, with surgical specimens (localized PC n = 81 and BPH n = 10) and metastatic cell lines (LNCaP, DU145, PC3 and PNT2 as control) by real-time PCR. Real-time PCR also determined the telomere length in the same experimental samples. All acquired data were associated with clinical parameters., Results: Genetic alterations are uncommon in PC, but POT1, TIN2, and TEN1 showed significantly more amplifications in the metastatic cancer. Except for CTC1 and TEN1, which are differentially expressed in localized PC samples, we did not detect an expression pattern relative to control and cell lines. Nevertheless, except for TEN1, the upregulation of all genes is associated with a worse prognosis in localized PC. We also found that increased telomere length is associated with disease aggressiveness in localized PC., Conclusion: The upregulation of shelterin and CST genes creates an environment that favors telomere elongation, giving selective advantages for localized PC cells to progress to more aggressive stages of the disease., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)