RESUMEN
Neutrophils sense microbes and host inflammatory mediators, and traffic to sites of infection where they direct a broad armamentarium of antimicrobial products against pathogens. Neutrophils are also activated by damage-associated molecular patterns (DAMPs), which are products of cellular injury that stimulate the innate immune system through pathways that are similar to those activated by microbes. Neutrophils and platelets become activated by injury, and cluster and cross-signal to each other with the cumulative effect of driving antimicrobial defense and hemostasis. In addition, neutrophil extracellular traps are extracellular chromatin and granular constituents that are generated in response to microbial and damage motifs and are pro-thrombotic and injurious. Although neutrophils can worsen tissue injury, neutrophils may also have a role in facilitating wound repair following injury. A central theme of this review relates to how critical functions of neutrophils that evolved to respond to infection and damage modulate the tumor microenvironment (TME) in ways that can promote or limit tumor progression. Neutrophils are reprogrammed by the TME, and, in turn, can cross-signal to tumor cells and reshape the immune landscape of tumors. Importantly, promising new therapeutic strategies have been developed to target neutrophil recruitment and function to make cancer immunotherapy more effective.
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Trampas Extracelulares , Neutrófilos , Humanos , Plaquetas/metabolismo , Plaquetas/patología , Células Endoteliales , Inflamación , Linfocitos T , Trampas Extracelulares/metabolismoRESUMEN
ABSTRACT: Triple-negative breast cancer (TNBC) is an aggressive tumor entity in which immune checkpoint (IC) molecules are primarily synthesized in the tumor environment. Here, we report that procoagulant platelets bear large amounts of such immunomodulatory factors and that the presence of these cellular blood components in TNBC relates to protumorigenic immune-cell activity and impaired survival. Mechanistically, tumor-released nucleic acids attract platelets to the aberrant tumor microvasculature, where they undergo procoagulant activation, thus delivering specific stimulatory and inhibitory IC molecules. This concomitantly promotes protumorigenic myeloid leukocyte responses and compromises antitumorigenic lymphocyte activity, ultimately supporting tumor growth. Interference with platelet-leukocyte interactions prevented immune cell misguidance and suppressed tumor progression, nearly as effective as systemic IC inhibition. Hence, our data uncover a self-sustaining mechanism of TNBC by using platelets to misdirect immune-cell responses. Targeting this irregular multicellular interplay may represent a novel immunotherapeutic strategy for TNBC without the adverse effects of systemic IC inhibition.
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Plaquetas , Neoplasias de la Mama Triple Negativas , Neoplasias de la Mama Triple Negativas/inmunología , Neoplasias de la Mama Triple Negativas/patología , Humanos , Plaquetas/inmunología , Plaquetas/patología , Plaquetas/metabolismo , Femenino , Ratones , Animales , Escape del Tumor , Línea Celular Tumoral , Evasión InmuneRESUMEN
ABSTRACT: A common feature in patients with abdominal aortic aneurysms (AAAs) is the formation of a nonocclusive intraluminal thrombus (ILT) in regions of aortic dilation. Platelets are known to maintain hemostasis and propagate thrombosis through several redundant activation mechanisms, yet the role of platelet activation in the pathogenesis of AAA-associated ILT is still poorly understood. Thus, we sought to investigate how platelet activation affects the pathogenesis of AAA. Using RNA sequencing, we identified that the platelet-associated transcripts are significantly enriched in the ILT compared with the adjacent aneurysm wall and healthy control aortas. We found that the platelet-specific receptor glycoprotein VI (GPVI) is among the top enriched genes in AAA ILT and is increased on the platelet surface of patients with AAAs. Examination of a specific indicator of platelet activity, soluble GPVI (sGPVI), in 2 independent cohorts of patients with AAAs is highly predictive of an AAA diagnosis and associates more strongly with aneurysm growth rate than D-dimer in humans. Finally, intervention with the anti-GPVI antibody (JAQ1) in mice with established aneurysms blunted the progression of AAA in 2 independent mouse models. In conclusion, we show that the levels of sGPVI in humans can predict a diagnosis of AAA and AAA growth rate, which may be critical in the identification of high-risk patients. We also identify GPVI as a novel platelet-specific AAA therapeutic target, with minimal risk of adverse bleeding complications, for which none currently exists.
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Aneurisma de la Aorta Abdominal , Glicoproteínas de Membrana Plaquetaria , Animales , Humanos , Ratones , Aneurisma de la Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/metabolismo , Plaquetas/metabolismo , Plaquetas/patología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Activación Plaquetaria , Glicoproteínas de Membrana Plaquetaria/metabolismo , Glicoproteínas de Membrana Plaquetaria/genética , Trombosis/metabolismo , Trombosis/patología , Trombosis/etiologíaRESUMEN
This review focuses on the dual role of platelets in atherosclerosis and thrombosis, exploring their involvement in inflammation, angiogenesis, and plaque formation, as well as their hemostatic and prothrombotic functions. Beyond their thrombotic functions, platelets engage in complex interactions with diverse cell types, influencing disease resolution and progression. The contribution of platelet degranulation helps in the formation of atheromatous plaque, whereas the reciprocal interaction with monocytes adds complexity. Alterations in platelet membrane receptors and signaling cascades contribute to advanced atherosclerosis, culminating in atherothrombotic events. Understanding these multifaceted roles of platelets will lead to the development of targeted antiplatelet strategies for effective cardiovascular disease prevention and treatment. Understanding platelet functions in atherosclerosis and atherothrombosis at different stages of disease will be critical for designing targeted treatments and medications to prevent or cure the disease Through this understanding, platelets can be targeted at specific times in the atherosclerosis process, possibly preventing the development of atherothrombosis.
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Aterosclerosis , Plaquetas , Trombosis , Humanos , Aterosclerosis/patología , Plaquetas/metabolismo , Plaquetas/patología , Trombosis/patología , Animales , Inflamación/patologíaRESUMEN
Thromboinflammation is a complex pathology associated with inflammation and coagulation. In cases of cardiovascular disease, in particular ischemia-reperfusion injury, thromboinflammation is a common complication. Increased understanding of thromboinflammation depends on an improved concept of the mechanisms of cells and proteins at the axis of coagulation and inflammation. Among these elements are activated protein C and platelets. This review summarizes the complex interactions of activated protein C and platelets regulating thromboinflammation in cardiovascular disease. By unraveling the pathways of platelets and APC in the inflammatory and coagulation cascades, this review summarizes the role of these vital mediators in the development and perpetuation of heart disease and the thromboinflammation-driven complications of cardiovascular disease. Furthermore, this review emphasizes the significance of the counteracting effects of platelets and APC and their combined role in disease states.
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Coagulación Sanguínea , Plaquetas , Inflamación , Daño por Reperfusión Miocárdica , Proteína C , Humanos , Plaquetas/metabolismo , Plaquetas/patología , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Inflamación/metabolismo , Inflamación/patología , Coagulación Sanguínea/fisiología , Proteína C/metabolismo , AnimalesRESUMEN
BACKGROUND: Aortic stenosis (AS) is driven by progressive inflammatory and fibrocalcific processes regulated by circulating inflammatory and valve resident endothelial and interstitial cells. The impact of platelets, platelet-derived mediators, and platelet-monocyte interactions on the acceleration of local valvular inflammation and mineralization is presently unknown. METHODS: We prospectively enrolled 475 consecutive patients with severe symptomatic AS undergoing aortic valve replacement. Clinical workup included repetitive echocardiography, analysis of platelets, monocytes, chemokine profiling, aortic valve tissue samples for immunohistochemistry, and gene expression analysis. RESULTS: The patients were classified as fast-progressive AS by the median ∆Vmax of 0.45 m/s per year determined by echocardiography. Immunohistological aortic valve analysis revealed enhanced cellularity in fast-progressive AS (slow- versus fast-progressive AS; median [interquartile range], 247 [142.3-504] versus 717.5 [360.5-1234]; P<0.001) with less calcification (calcification area, mm2: 33.74 [27.82-41.86] versus 20.54 [13.52-33.41]; P<0.001). MIF (macrophage migration inhibitory factor)-associated gene expression was significantly enhanced in fast-progressive AS accompanied by significantly elevated MIF plasma levels (mean±SEM; 6877±379.1 versus 9959±749.1; P<0.001), increased platelet activation, and decreased intracellular MIF expression indicating enhanced MIF release upon platelet activation (CD62P, %: median [interquartile range], 16.8 [11.58-23.8] versus 20.55 [12.48-32.28], P=0.005; MIF, %: 4.85 [1.48-9.75] versus 2.3 [0.78-5.9], P<0.001). Regression analysis confirmed that MIF-associated biomarkers are strongly associated with an accelerated course of AS. CONCLUSIONS: Our findings suggest a key role for platelet-derived MIF and its interplay with circulating and valve resident monocytes/macrophages in local and systemic thromboinflammation during accelerated AS. MIF-based biomarkers predict an accelerated course of AS and represent a novel pharmacological target to attenuate progression of AS.
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Estenosis de la Válvula Aórtica , Válvula Aórtica , Biomarcadores , Progresión de la Enfermedad , Oxidorreductasas Intramoleculares , Factores Inhibidores de la Migración de Macrófagos , Tromboinflamación , Humanos , Estenosis de la Válvula Aórtica/genética , Estenosis de la Válvula Aórtica/patología , Estenosis de la Válvula Aórtica/metabolismo , Estenosis de la Válvula Aórtica/sangre , Factores Inhibidores de la Migración de Macrófagos/sangre , Factores Inhibidores de la Migración de Macrófagos/genética , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Masculino , Femenino , Anciano , Estudios Prospectivos , Válvula Aórtica/patología , Válvula Aórtica/metabolismo , Válvula Aórtica/diagnóstico por imagen , Oxidorreductasas Intramoleculares/genética , Oxidorreductasas Intramoleculares/metabolismo , Oxidorreductasas Intramoleculares/sangre , Biomarcadores/sangre , Tromboinflamación/genética , Tromboinflamación/patología , Tromboinflamación/metabolismo , Plaquetas/metabolismo , Plaquetas/patología , Anciano de 80 o más Años , Monocitos/metabolismo , Persona de Mediana Edad , Implantación de Prótesis de Válvulas Cardíacas , Factores de Tiempo , Índice de Severidad de la Enfermedad , Calcinosis/patología , Calcinosis/genética , Calcinosis/sangre , Calcinosis/metabolismoRESUMEN
BACKGROUND: In addition to their fundamental roles in preserving vascular integrity, platelets also contribute to tumor angiogenesis and metastasis. However, despite being a reservoir for angiogenic and metastatic cytokines, platelets also harbor negative regulators of tumor progression. Angpt1 (angiopoietin-1) is a cytokine essential for developmental angiogenesis that also protects against tumor cell metastasis through an undefined mechanism. Although activated platelets release Angpt1 from α-granules into circulation, the contributions of platelet Angpt1 to tumor growth, angiogenesis, and metastasis have not been investigated. METHODS: Using cytokine arrays and ELISAs, we first compared platelet Angpt1 levels in breast and melanoma mouse tumor models to tumor-free controls. We then assessed tumor growth and metastasis in mice lacking megakaryocyte and platelet Angpt1 (Angpt1Plt KO). The spontaneous metastasis of mammary-injected tumor cells to the lungs was quantified using RT-PCR (reverse transcription-polymerase chain reaction). The lung colonization of intravenously injected tumor cells and tumor cell extravasation were determined using fluorescent microscopy and flow cytometry. RESULTS: Platelet Angpt1 is selectively upregulated in the PyMT (polyoma middle tumor antigen) breast cancer mouse model, and platelets are the principal source of Angpt1 in blood circulation. While primary tumor growth and angiogenesis were unaffected, Angpt1Plt KO mice had both increased spontaneous lung metastasis and tumor cell lung colonization following mammary or intravenous injection, respectively. Although platelet Angpt1 did not affect initial tumor cell entrapment in the lungs, Angpt1Plt KO mice had increased tumor cell retention and extravasation. Serum from Angpt1Plt KO mice increased endothelial permeability and reduced VE (vascular endothelial)-cadherin expression at endothelial junctions compared with serum from control mice (Angpt1WT). CONCLUSIONS: Platelets provide an intravascular source of Angpt1 that restrains tumor metastasis by preserving the lung microvasculature to limit tumor cell extravasation.
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Angiopoyetina 1 , Plaquetas , Neoplasias Pulmonares , Ratones Noqueados , Neovascularización Patológica , Animales , Angiopoyetina 1/genética , Angiopoyetina 1/metabolismo , Angiopoyetina 1/sangre , Plaquetas/metabolismo , Plaquetas/patología , Femenino , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/prevención & control , Ratones Endogámicos C57BL , Melanoma Experimental/patología , Melanoma Experimental/metabolismo , Melanoma Experimental/irrigación sanguínea , Melanoma Experimental/sangre , Melanoma Experimental/secundario , Melanoma Experimental/genética , Línea Celular Tumoral , Ratones , Neoplasias Mamarias Experimentales/patología , Neoplasias Mamarias Experimentales/genética , Neoplasias Mamarias Experimentales/metabolismo , Neoplasias Mamarias Experimentales/sangre , Carga Tumoral , Modelos Animales de EnfermedadRESUMEN
PURPOSE OF REVIEW: Thrombo-inflammation is a multifaceted pathologic process involving various cells such as platelets, neutrophils, and monocytes. In recent years, microRNAs have been consistently implicated as regulators of these cells. RECENT FINDINGS: MicroRNAs play a regulatory role in several platelet receptors that have recently been identified as contributing to thrombo-inflammation and neutrophil extracellular trap (NET) formation. In addition, a growing body of evidence has shown that several intracellular and extracellular microRNAs directly promote NET formation. SUMMARY: Targeting microRNAs is a promising therapeutic approach to control thrombosis in patients with both infectious and noninfectious inflammatory diseases. Future research efforts should focus on elucidating the specific roles of microRNAs in thrombo-inflammation and translating these findings into tangible benefits for patients.
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Trampas Extracelulares , MicroARNs , Trombosis , Humanos , MicroARNs/genética , Plaquetas/patología , Trombosis/genética , Inflamación/genética , Inflamación/patología , Neutrófilos/patologíaRESUMEN
PURPOSE OF REVIEW: Cardiovascular disease is a major cause of death worldwide. Platelets play a key role in this pathological process. The serine protease thrombin is a critical regulator of platelet reactivity through protease activated receptors-1 (PAR1) and PAR4. Since targeting PAR4 comes with a low chance for bleeding, strategies blocking PAR4 function have great antithrombotic potential. Here, we reviewed the literature on platelet PAR4 with a particular focus on its role in thromboinflammation. RECENT FINDINGS: Functional PAR4 variants are associated with reduced venous thrombosis risk (rs2227376) and increased risk for ischemic stroke (rs773902). Recent advances have allowed for the creation of humanized mouse lines in which human PAR4 is express instead of murine PAR4. This has led to a better understanding of the discrepancies between human and murine PAR4. It also made it possible to introduce single nucleotide polymorphisms (SNPs) in mice allowing to directly test the in vivo functional effects of a specific SNP and to develop in vivo models to study mechanistic and pharmacologic alterations induced by a SNP. SUMMARY: PAR4 plays an important role in cardiovascular diseases including stroke, myocardial infarction and atherosclerosis. Targeting PAR4 hold great potential as a safe antithrombotic strategy.
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Receptores de Trombina , Humanos , Receptores de Trombina/metabolismo , Receptores de Trombina/genética , Animales , Ratones , Polimorfismo de Nucleótido Simple , Trombosis/metabolismo , Plaquetas/metabolismo , Plaquetas/patologíaRESUMEN
BACKGROUND: Tumor cells continue to evolve the metastatic potential in response to signals provided by the external microenvironment during metastasis. Platelets closely interact with tumor cells during hematogenous metastasis and facilitate tumor development. However, the molecular mechanisms underlying this process are not fully understood. METHODS: RNA-sequencing was performed to screen differentially expressed genes mediated by platelets. The effects of platelet and CD39 on tumor metastasis were determined by experimental metastasis models with WT, NCG and CD39-/- mice. RESULTS: RNA-sequencing results showed that platelets significantly up-regulated CD39 expression in tumor cells. CD39 is a novel immune checkpoint molecule and a key driver of immunosuppression. Our data provided evidence that the expression of CD39 was enhanced by platelets in a platelet-tumor cell contact dependent manner. Although the role of CD39 expressed by immune cells is well established, the effect of CD39 expressed by tumor cells on tumor cell behavior, anti-tumor immunity and tumor metastasis is unclear. We found that CD39 promoted tumor cell invasion, but had no effect on proliferation and migration. Notably, we showed that the ability of platelets to prime tumor cells for metastasis depends on CD39 in the experimental tumor metastasis model. CD39 silencing resulted in fewer experimental metastasis formation, and this anti-metastasis effect was significantly reduced in platelet-depleted mice. Furthermore, overexpression of CD39 in tumor cells promoted metastasis. In order to eliminate the effect of CD39 expressed in cells other than tumor cells, we detected tumor metastasis in CD39-/- mice and obtained similar results. Moreover, overexpression of CD39 in tumor cells inhibited antitumor immunity. Finally, the data from human samples also supported our findings. CONCLUSIONS: Our study shows that direct contact with platelets induces CD39 expression in tumor cells, leading to immune suppression and promotion of metastasis.
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Antígenos CD , Apirasa , Plaquetas , Metástasis de la Neoplasia , Animales , Apirasa/genética , Apirasa/metabolismo , Plaquetas/metabolismo , Plaquetas/patología , Ratones , Antígenos CD/genética , Antígenos CD/metabolismo , Humanos , Línea Celular Tumoral , Femenino , Ratones Noqueados , Movimiento Celular , Microambiente Tumoral/inmunología , Regulación Neoplásica de la Expresión GénicaRESUMEN
Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. Despite overlap between genetic risk loci for ALL and hematologic traits, the etiological relevance of dysregulated blood-cell homeostasis remains unclear. We investigated this question in a genome-wide association study (GWAS) of childhood ALL (2,666 affected individuals, 60,272 control individuals) and a multi-trait GWAS of nine blood-cell indices in the UK Biobank. We identified 3,000 blood-cell-trait-associated (p < 5.0 × 10-8) variants, explaining 4.0% to 23.9% of trait variation and including 115 loci associated with blood-cell ratios (LMR, lymphocyte-to-monocyte ratio; NLR, neutrophil-to-lymphocyte ratio; PLR, platelet-to-lymphocyte ratio). ALL susceptibility was genetically correlated with lymphocyte counts (rg = 0.088, p = 4.0 × 10-4) and PLR (rg = -0.072, p = 0.0017). In Mendelian randomization analyses, genetically predicted increase in lymphocyte counts was associated with increased ALL risk (odds ratio [OR] = 1.16, p = 0.031) and strengthened after accounting for other cell types (OR = 1.43, p = 8.8 × 10-4). We observed positive associations with increasing LMR (OR = 1.22, p = 0.0017) and inverse effects for NLR (OR = 0.67, p = 3.1 × 10-4) and PLR (OR = 0.80, p = 0.002). Our study shows that a genetically induced shift toward higher lymphocyte counts, overall and in relation to monocytes, neutrophils, and platelets, confers an increased susceptibility to childhood ALL.
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Biomarcadores de Tumor/genética , Plaquetas/patología , Linfocitos/patología , Monocitos/patología , Neutrófilos/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Sitios de Carácter Cuantitativo , Adulto , Anciano , Estudios de Casos y Controles , Niño , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Análisis de la Aleatorización Mendeliana , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Pronóstico , Estudios Prospectivos , Reino Unido/epidemiologíaRESUMEN
Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder characterized by isolated thrombocytopenia. Its pathogenesis is complex relying in large part on destruction of platelets recognized by autoantibodies within the spleen. However, other mechanisms, such as platelet desialylation, may play a role in platelet reduction by accelerating their clearance in the liver. In their study, Mendoza and colleagues reported on platelet scintigraphy performed in 51 ITP patients, showing a response in 87.5% when the sequestration occurred in the spleen versus 45% in case of non-splenic destruction. Platelet desialylation was also measured after splenectomy and found to be higher in non-responder patients. These latter results, while requiring confirmation prior to splenectomy, support platelet desialylation may also be a potential biomarker of non-response to splenectomy. Commentary on: Mendoza et al. Study of platelet kinetics in immune thrombocytopenia to predict splenectomy response. Br J Haematol 2024;204:315-323.
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Púrpura Trombocitopénica Idiopática , Trombocitopenia , Humanos , Esplenectomía , Trombocitopenia/patología , Plaquetas/patología , Bazo/patologíaRESUMEN
BACKGROUND: Our previous work indicated that the addition of lobaplatin to combined therapy with taxane and anthracycline can improve the pathological complete response rate of neoadjuvant therapy for triple-negative breast cancer (TNBC) and lengthen long-term survival significantly, but the therapeutic markers of this regimen are unclear. METHODS: Eighty-three patients who met the inclusion criteria were included in this post hoc analysis. We analyzed the association between platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) before neoadjuvant chemotherapy with the efficacy and prognosis after treatment with docetaxel, epirubicin, and lobaplatin neoadjuvant chemotherapy regimen. χ2 test and Cox regression were used to analyze the association between PLR and NLR with total pathologic complete response (tpCR), as well as the association between PLR and NLR with event-free survival (EFS) and overall survival (OS), respectively. RESULTS: The tpCR rate in the PLR- group was 49.0% (25/51), which was significantly higher than that in the PLR+ group (25.0% [8/32], Pâ =â .032). The tpCR rate in the NLR- group was 49.1% (26/53), which was significantly higher than that in the NLR+ group (23.3% [7/30], Pâ =â .024). The tpCR rate of the PLR-NLR- (PLR- and NLR-) group was 53.7% (22/41), which was significantly higher than that of the PLR+/NLR+ (PLR+ or/and NLR+) group (26.1% [11/42]; Pâ =â .012). EFS and OS in the NLR+ group were significantly shorter than those in the NLR- group (Pâ =â .028 for EFS; Pâ =â .047 for OS). Patients in the PLR-NLR- group had a longer EFS than those in the PLR+/NLR+ group (Pâ =â .002). CONCLUSION: PLR and NLR could be used to predict the efficacy of neoadjuvant therapy with the taxane, anthracycline, and lobaplatin regimen for patients with TNBC, as patients who had lower PLR and NLR values had a higher tpCR rate and a better long-term prognosis.
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Ciclobutanos , Terapia Neoadyuvante , Compuestos Organoplatinos , Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/sangre , Neoplasias de la Mama Triple Negativas/mortalidad , Femenino , Terapia Neoadyuvante/métodos , Pronóstico , Persona de Mediana Edad , Ciclobutanos/farmacología , Ciclobutanos/uso terapéutico , Ciclobutanos/administración & dosificación , Compuestos Organoplatinos/uso terapéutico , Compuestos Organoplatinos/farmacología , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Anciano , Neutrófilos/metabolismo , Biomarcadores de Tumor/sangre , Linfocitos/metabolismo , Plaquetas/patología , Estudios RetrospectivosRESUMEN
Thrombocytopenia is a common symptom and one of the warning signs of dengue virus (DENV) infection. Platelet depletion is critical as it may lead to other severe dengue symptoms. Understanding the molecular events of this condition during dengue infection is challenging because of the multifaceted factors involved in DENV infection and the dynamics of the disease progression. Platelet levels depend on the balance between platelet production and platelet consumption or clearance. Megakaryopoiesis and thrombopoiesis, two interdependent processes in platelet production, are hampered during dengue infection. Conversely, platelet elimination via platelet activation, apoptosis and clearance processes are elevated. Together, these anomalies contribute to thrombocytopenia in dengue patients. Targeting the molecular events of dengue-mediated thrombocytopenia shows great potential but still requires further investigation. Nonetheless, the application of new knowledge in this field, such as immature platelet fraction analysis, may facilitate physicians in monitoring the progression of the disease.
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Plaquetas , Virus del Dengue , Dengue , Trombocitopenia , Humanos , Trombocitopenia/etiología , Trombocitopenia/virología , Dengue/complicaciones , Dengue/sangre , Plaquetas/metabolismo , Plaquetas/patología , Animales , Trombopoyesis , Activación Plaquetaria , ApoptosisRESUMEN
Variants in the 5' UTR of ANKRD26 are a common cause of inherited thrombocytopenia (ANKRD26-RT), and are associated with sustained ANKRD26 expression, which inhibits megakaryocyte maturation and proplatelet formation. ANKRD26 expression is controlled by the binding of a RUNX1/FLI1 complex to the 5' UTR. To date, all reported ANKRD26-RD associated variants have been within the RUNX1 binding site and a 22 base pair flanking region. Here, we report a novel variant in the 5' UTR of ANKRD26, c.-107C>T. This variant is in the FLI1 binding site, and is predicted to disrupt FLI1 binding due to loss of a hydrogen bond with FLI1. Differentiated PBMCs from affected family members showed impaired megakaryocyte maturation and proplatelet formation and sustained expression of ANKRD26, and platelets from affected family members had higher ANKRD26 expression than control platelets. The variant increased activity of the ANKRD26 promotor in a reporter assay. We also provide evidence that the previously reported c.-140C>G ANKRD26 5' UTR variant is benign and not associated with thrombocytopenia. Identification of the c.-107C>T variant extends the range of the regulatory region in the 5' UTR of ANKRD26 that is associated with ANKRD26-RT.
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Regiones no Traducidas 5' , Proteína Proto-Oncogénica c-fli-1 , Trombocitopenia , Humanos , Trombocitopenia/genética , Trombocitopenia/patología , Regiones no Traducidas 5'/genética , Sitios de Unión , Proteína Proto-Oncogénica c-fli-1/genética , Proteína Proto-Oncogénica c-fli-1/metabolismo , Masculino , Femenino , Linaje , Megacariocitos/metabolismo , Megacariocitos/patología , Plaquetas/metabolismo , Plaquetas/patología , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Unión Proteica , Predisposición Genética a la Enfermedad , Péptidos y Proteínas de Señalización IntercelularRESUMEN
Tyrosine phosphorylation of extracellular proteins is observed in cell cultures and in vivo, but little is known about the functional roles of tyrosine phosphorylation of extracellular proteins. Vertebrate lonesome kinase (VLK) is a broadly expressed secretory pathway tyrosine kinase present in platelet α-granules. It is released from platelets upon activation and phosphorylates substrates extracellularly. Its role in platelet function, however, has not been previously studied. In human platelets, we identified phosphorylated tyrosines mapped to luminal or extracellular domains of transmembrane and secreted proteins implicated in the regulation of platelet activation. To determine the role of VLK in extracellular tyrosine phosphorylation and platelet function, we generated mice with a megakaryocyte/platelet-specific deficiency of VLK. Platelets from these mice are normal in abundance and morphology but have significant changes in function both in vitro and in vivo. Resting and thrombin-stimulated VLK-deficient platelets exhibit a significant decrease in several tyrosine phosphobands. Results of functional testing of VLK-deficient platelets show decreased protease-activated receptor 4-mediated and collagen-mediated platelet aggregation but normal responses to adenosine 5'-diphosphate. Dense granule and α-granule release are reduced in these platelets. Furthermore, VLK-deficient platelets exhibit decreased protease-activated receptor 4-mediated Akt (S473) and Erk1/2 (T202/Y204) phosphorylation, indicating altered proximal signaling. In vivo, mice lacking VLK in megakaryocytes/platelets display strongly reduced platelet accumulation and fibrin formation after laser-induced injury of cremaster arterioles compared with control mice but with normal bleeding times. These studies show that the secretory pathway tyrosine kinase VLK is critical for stimulus-dependent platelet activation and thrombus formation, providing the first evidence that a secreted protein kinase is required for normal platelet function.
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Plaquetas/metabolismo , Activación Plaquetaria , Proteínas Tirosina Quinasas/metabolismo , Trombosis/metabolismo , Animales , Plaquetas/patología , Eliminación de Gen , Células HEK293 , Humanos , Ratones Transgénicos , Proteínas Tirosina Quinasas/genética , Trombosis/patologíaRESUMEN
BACKGROUND: Anti-PD-(L)1 immunotherapy has emerged as a promising treatment approach for non-small cell lung cancer (NSCLC), though the response rates remain low. Pre-treatment response prediction may improve patient allocation for immunotherapy. Blood platelets act as active immune-like cells, thereby constraining T-cell activity, propagating cancer metastasis, and adjusting their spliced mRNA content. OBJECTIVE: We investigated whether platelet RNA profiles before start of nivolumab anti-PD1 immunotherapy may predict treatment responses. METHODS: We performed RNA-sequencing of platelet RNA samples isolated from stage III-IV NSCLC patients before treatment with nivolumab. Treatment response was scored by the RECIST-criteria. Data were analyzed using a predefined thromboSeq analysis including a particle-swarm-enhanced support vector machine (PSO/SVM) classification algorithm. RESULTS: We collected and processed a 286-samples cohort, separated into a training/evaluation and validation series and subjected those to training of the PSO/SVM-classification algorithm. We observed only low classification accuracy in the 107-samples validation series (area under the curve (AUC) training series: 0.73 (95% -CI: 0.63-0.84, nâ=â88 samples), AUC evaluation series: 0.64 (95% -CI: 0.51-0.76, nâ=â91 samples), AUC validation series: 0.58 (95% -CI: 0.45-0.70, nâ=â107 samples)), employing a five-RNAs biomarker panel. CONCLUSIONS: We concluded that platelet RNA may have minimally discriminative capacity for anti-PD1 nivolumab response prediction, with which the current methodology is insufficient for diagnostic application.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Nivolumab/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Plaquetas/patología , ARN/genéticaRESUMEN
BACKGROUND: Inflammation plays a pivotal role in the progression of prostate cancer (PCa). Several immune-inflammatory indices, including neutrophil to lymphocyte ratio (NLR), derived neutrophil to lymphocyte ratio (dNLR), lymphocyte to monocyte ratio (LMR) and platelet to lymphocyte ratio (PLR), lung immune prognostic index (LIPI), systemic inflammation response index (SIRI) and systemic immune inflammation index (SII), have demonstrated their prognostic values in several solid malignancies. However, Comparisons of superiority with these seven indices' predictive efficacy within metastatic hormone-sensitive PCa (mHSPC) and metastatic castration-resistant PCa (mCRPC) remain uncertain. METHODS: We retrospectively included 407 patients diagnosed with mHSPC and 158 patients with mCRPC at West China Hospital from 2005 to 2022. The seven immune-inflammatory indices were computed based on hematological data of mHSPC at initial diagnosis and mCRPC at progression to CRPC. Prognostic value for castration-resistant prostate cancer-free survival (CFS), overall survival (OS), prostate-specific antigen progression-free survival (PSA-PFS) and prostate-specific antigen (PSA) response was assessed using Kaplan-Meier curves, Cox regression models, and chi-square tests. The predictive performance of each immune-inflammatory index was assessed using the area under the curve (AUC) in time-dependent receiver operating characteristic curve (ROC) analysis and C-index calculation. RESULTS: All seven immune-inflammatory indices were significantly associated with CFS and OS in the mHSPC cohort, as well as with PSA response, PSA-PFS, and OS in the mCRPC cohort. In the mHSPC cohort, LIPI consistently exhibited higher AUC values compared to NLR, dNLR, LMR, PLR, SII, and SIRI for predicting CFS and OS. This indicates that LIPI had a superior discriminative ability compared to the other indices (C-index of LIPI: 0.643 and 0.686 for CFS and OS, respectively). Notably, the predictive advantage of LIPI over other indices in the mHSPC stage diminished in the mCRPC stage. CONCLUSIONS: This study firstly confirmed the prognostic value of SII, SIRI and LIPI in mHSPC and mCRPC, and revealed that LIPI had a higher predictive power than NLR, dNLR, LMR, PLR, SII and SIRI in mHSPC. These non-invasive indices can enable clinicians to quickly assess the prognosis of patients.
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Neutrófilos , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Neoplasias de la Próstata Resistentes a la Castración/patología , Neoplasias de la Próstata Resistentes a la Castración/sangre , Neoplasias de la Próstata Resistentes a la Castración/inmunología , Neoplasias de la Próstata Resistentes a la Castración/mortalidad , Anciano , Estudios Retrospectivos , Persona de Mediana Edad , Pronóstico , Neutrófilos/inmunología , Inflamación , Linfocitos/inmunología , Antígeno Prostático Específico/sangre , Curva ROC , Anciano de 80 o más Años , Plaquetas/patología , Plaquetas/inmunologíaRESUMEN
PURPOSE: Bone metastases occur in 50-70% of patients with breast cancer (BC) and result in high mortality. Platelet distribution width (PDW), a commonly used parameter of activated platelets, has been associated with a poor prognosis in BC. We aim to investigate the prognostic role of PDW for bone metastasis in BC patients. METHODS: 515 patients who received BC surgery in the Harbin Medical University Cancer Hospital from July 1, 2016, to December 31, 2017, were reviewed. Patients' characteristics and platelet indices upon enrollment in this study were collected. The Kaplan-Meier method was used to estimate the 5-year bone metastasis incidence. The univariate and multivariate Cox regression analyses were utilized to identify risk factors associated with bone metastasis. RESULTS: The patients with bone metastases exhibited lower PDW levels than the patients without bone metastases. Moreover, decreased PDW was significantly correlated with histologic type, multifocal disease, and lymph node status. In addition, the patients with reduced PDW levels were more likely to develop bone metastasis. Multivariate analysis showed that PDW was an independent predictor for bone metastasis. CONCLUSION: PDW is an independent predictor of bone metastasis in BC. Further research is warranted.
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Plaquetas , Neoplasias Óseas , Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Neoplasias de la Mama/sangre , Neoplasias Óseas/secundario , Neoplasias Óseas/sangre , Persona de Mediana Edad , Pronóstico , Plaquetas/patología , Anciano , Estudios Retrospectivos , Adulto , Periodo Preoperatorio , Factores de Riesgo , Recuento de Plaquetas , Estimación de Kaplan-MeierRESUMEN
BACKGROUND: Despite evidence supporting the high correlation of the novel platelet-to-albumin ratio (PAR) with survival in diverse malignancies, its prognostic relevance in nasopharyngeal carcinoma (NPC) remains underexplored. This study aimed to examine the link between PAR and overall survival (OS) in NPC and to establish a predictive model based on this biomarker. METHODS: We retrospectively assembled a cohort consisting of 858 NPC patients who underwent concurrent chemoradiotherapy (CCRT). Utilizing the maximally selected log-rank method, we ascertained the optimal cut-off point for the PAR. Subsequently, univariate and multivariate Cox proportional hazards models were employed to discern factors significantly associated with OS and to construct a predictive nomogram. Further, we subjected the nomogram's predictive accuracy to rigorous independent validation. RESULTS: The discriminative optimal PAR threshold was determined to be 4.47, effectively stratifying NPC patients into two prognostically distinct subgroups (hazard ratio [HR] = 0.53; 95% confidence interval [CI]: 0.28-0.98, P = 0.042). A predictive nomogram was formulated using the results from multivariate analysis, which revealed age greater than 45 years, T stage, N stage, and PAR score as independent predictors of OS. The nomogram demonstrated a commendable predictive capability for OS, with a C-index of 0.69 (95% CI: 0.64-0.75), surpassing the performance of the conventional staging system, which had a C-index of 0.56 (95% CI: 0.65-0.74). CONCLUSIONS: In the context of NPC patients undergoing CCRT, the novel nutritional-inflammatory biomarker PAR emerges as a promising, cost-efficient, easily accessible, non-invasive, and potentially valuable predictor of prognosis. The predictive efficacy of the nomogram incorporating the PAR score exceeded that of the conventional staging approach, thereby indicating its potential as an enhanced prognostic tool in this clinical setting.