Platelet "first responders" in wound response, cancer, and metastasis

Platelet-derived major histocompatibility complex class I coating on Treponema pallidum attenuates natural killer cell lethality

The evasive tactics of Treponema pallidum pose a major challenge in combating and eradicating syphilis. Natural killer (NK) cells mediate important effector functions in the control of pathogenic infection, preferentially eliminating targets with low or no expression of major histocompatibility complex (MHC) class I. To clarify T. pallidum's mechanisms in evading NK-mediated immunosurveillance, experiments were performed to explore the cross-talk relations among T. pallidum, NK cells, and platelets. T. pallidum adhered to, activated, and promoted particle secretion of platelets. After preincubation with T. pallidum, platelets expressed and secreted high levels of MHC class I, subsequently transferring them to the surface of T. pallidum, potentially inducing an immune phenotype characterized by the "pseudo-expression" of MHC class I on the surface of T. pallidum (hereafter referred to a "pseudo-expression" of MHC class I). The polA mRNA assay showed that platelet-preincubated T. pallidum group exhibited a significantly higher copy number of polA transcript than the T. pallidum group. The survival rate of T. pallidum mirrored that of polA mRNA, indicating that preincubation of T. pallidum with platelets attenuated NK cell lethality. Platelets pseudo-expressed the MHC class I ligand on the T. pallidum surface, facilitating binding to killer cell immunoglobulin-like receptors with two immunoglobulin domains and long cytoplasmic tail 3 (KIR2DL3) on NK cells and initiating dephosphorylation of Vav1 and phosphorylation of Crk, ultimately attenuating NK cell lethality. Our findings elucidate the mechanism by which platelets transfer MHC class I to the T. pallidum surface to evade NK cell immune clearance.

Prognostic role of dynamic changes in inflammatory indicators in patients with non-small cell lung cancer treated with immune checkpoint inhibitors-a retrospective cohort study

Background

Immune checkpoint inhibitors (ICIs) have become one of the standard treatments for non-small cell lung cancer (NSCLC) patients without driver mutations. However, a considerable proportion of patients suffer from severe immune side effects and fail to respond to ICIs. As effective biomarkers, programmed cell death ligand 1 (PD-L1) expression, microsatellite instability (MSI), the tumor mutation burden (TMB) and tumor-infiltrating lymphocytes (TILs) require invasive procedures that place heavy physical and psychological burdens on patients. This study aims to identify simple and effective markers to optimize patient selection through therapeutic decisions and outcome prediction.

Methods

This retrospective study comprised 95 patients with metastatic NSCLC who were treated with ICIs either as the standard of care or in a clinical trial. The following data were extracted from the medical records. The baseline and dynamic neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were calculated in the present study. Responses were assessed by computed tomography (CT) imaging and classified according to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 every 6-12 weeks during treatment.

Results

In total, 95 patients were included in the present study. The median age of patients was 61 years, 83.2% (79/95) patients were male, 62.1% (59/95) were former or current smokers, 66.3% (63/95) had adenocarcinoma, 93.7% (89/95) had stage IV disease, and 87.4% were without molecular alterations. A higher overall response rate (ORR) and prolonged median progression-free survival (PFS) was observed in patients with a lower cycle 3 (C3) NLR [7.7 vs. 5.5 months, hazard ratio (HR): 1.70, 95% confidence interval (CI): 0.90-3.22; P=0.12] and derived NLR (dNLR) (8.2 vs. 5.6 months, HR: 1.67, 95% CI: 0.94-2.97; P=0.08). After two cycles of ICI treatment, patients who had an increased NLR, dNLR, and PLR had a lower ORR and an inferior median PFS than those with a decreased NLR (5.5 vs. 8.5 months, HR: 1.87, 95% CI: 1.09-3.21; P=0.02), dNLR (5.6 vs. 8.4 months, HR: 1.49, 95% CI: 0.87-2.57; P=0.15), and PLR (11.8 vs. 5.5 months, HR: 2.28, 95% CI: 1.32-3.94; P=0.003). Moreover, patients with both an increased NLR and PLR had a worse ORR and median PFS than those with either an increased NLR or PLR, or both an increased NLR and PLR (11.8 vs. 5.5 vs. 5.6 months, P=0.003). In addition, the dynamic changes in the PLR could serve as an independent predictive factor of PFS in NSCLC patients treated with ICIs.

Conclusions

Elevated dynamic changes in the NLR and PLR were associated with lower response rates and shorter PFS in the patients with NSCLC treated with ICIs. Our results also highlight the role of dynamic changes in the PLR in identifying patients with NSCLC who could benefit from ICIs.

Platelets at the intersection of inflammation and coagulation in the APC-mediated response to myocardial ischemia/reperfusion injury

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.

Stable diffusion gradients in microfluidic conduits bounded by fluid walls

Assays mimicking in vitro the concentration gradients triggering biological responses like those involved in fighting infections and blood clotting are essential for biomedical research. Microfluidic assays prove especially attractive as they allow precise control of gradient shape allied to a reduction in scale. Conventional microfluidic devices are fabricated using solid plastics that prevent direct access to responding cells. Fluid-walled microfluidics allows the manufacture of circuits on standard Petri dishes in seconds, coupled to simple operating methods; cell-culture medium sitting in a standard dish is confined to circuits by fluid walls made of an immiscible fluorocarbon. We develop and experimentally validate an analytical model of diffusion between two or more aqueous streams flowing at different rates into a fluid-walled conduit with the cross-section of a circular segment. Unlike solid walls, fluid walls morph during flows as pressures fall, with wall shape changing down the conduit. The model is validated experimentally for Fourier numbers < 0.1 using fluorescein diffusing between laminar streams. It enables a priori prediction of concentration gradients throughout a conduit, so allowing rapid circuit design as well as providing bio-scientists with an accurate way of predicting local concentrations of bioactive molecules around responsive and non-responsive cells.

The Role of TLR-2 in Lethal COVID-19 Disease Involving Medullary and Resident Lung Megakaryocyte Up-Regulation in the Microthrombosis Mechanism

Patients with COVID-19 have coagulation and platelet disorders, with platelet alterations and thrombocytopenia representing negative prognostic parameters associated with severe forms of the disease and increased lethality.

METHODS

The aim of this study was to study the expression of platelet glycoprotein IIIa (CD61), playing a critical role in platelet aggregation, together with TRL-2 as a marker of innate immune activation.

RESULTS

A total of 25 patients were investigated, with the majority (24/25, 96%) having co-morbidities and dying from a fatal form of SARS-CoV-2(+) infection (COVID-19+), with 13 men and 12 females ranging in age from 45 to 80 years. When compared to a control group of SARS-CoV-2 (-) negative lungs (COVID-19-), TLR-2 expression was up-regulated in a subset of patients with deadly COVID-19 fatal lung illness. The proportion of Spike-1 (+) patients found by PCR and ISH correlates to the proportion of Spike-S1-positive cases as detected by digital pathology examination. Furthermore, CD61 expression was considerably higher in the lungs of deceased patients. In conclusion, we demonstrate that innate immune prolonged hyperactivation is related to platelet/megakaryocyte over-expression in the lung.

CONCLUSIONS

Microthrombosis in deadly COVID-19+ lung disease is associated with an increase in the number of CD61+ platelets and megakaryocytes in the pulmonary interstitium, as well as their functional activation; this phenomenon is associated with increased expression of innate immunity TLR2+ cells, which binds the SARS-CoV-2 E protein, and significantly with the persistence of the Spike-S1 viral sequence.

Development and experimental validation of an M2 macrophage and platelet-associated gene signature to predict prognosis and immunotherapy sensitivity in bladder cancer

Platelets and M2 macrophages both play crucial roles in tumorigenesis, but their relationship and the prognosis value of the relative genes in bladder cancer (BLCA) remain obscure. In the present study, we found that platelets stimulated by BLCA cell lines could promote M2 macrophage polarization, and platelets were significantly associated with the infiltration of M2 macrophages in BLCA samples. Through the bioinformatic analyses, A2M, TGFB3, and MYLK, which were associated with platelets and M2 macrophages, were identified and verified in vitro and then included in the predictive model. A platelet and M2 macrophage-related gene signature was constructed to evaluate the prognosis and immunotherapeutic sensitivity, helping to guide personalized treatment and to disclose the underlying mechanisms.

Predictive value of NLR and PLR for immune-related adverse events: a systematic review and meta-analysis

BACKGROUND

Currently, there is a lack of affordable and accessible indicators that can accurately predict immune-related adverse events (irAEs) resulting from the use of immune checkpoint inhibitors (ICIs). In order to address this knowledge gap, our study explore the potential predictive value of two ratios, namely the neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR), for irAEs in cancer patients.

METHODS

A systematic search was performed in PubMed, Embase, and the Cochrane library. Studies involving NLR or PLR with irAEs were included. Quality and risk of bias of the selected studies were assessed. Forest plots were created based on Cox model analysis. Random effects meta-analyses were conducted to estimate odds ratio (OR) and its 95% confidence interval (CI).

RESULTS

After screening 594 studies, a total of 7 eligible studies with 1068 cancer patients were included. Analysis based on Cox regression showed that low neutrophil-lymphocyte ratio (L-NLR) (OR = 3.02, 95% CI 1.51 to 6.05, P = 0.002) and low platelet-lymphocyte ratio (L-PLR) (OR = 1.83, 95% CI 1.21 to 2.76, P = 0.004) were associated with irAEs. In the subgroup analysis of cut-off value, when the NLR cut-off value was 3, irAEs was significantly correlated with NLR (OR = 2.63, 95% CI 1.63 to 4.26, P < 0.001).

CONCLUSIONS

Both L-NLR and L-PLR have been found to be significantly associated with irAEs. Consequently, patients identified as being at a higher risk for irAEs should be subjected to more diligent monitoring and close observation.

Study on the mechanism of MDSC-platelets and their role in the breast cancer microenvironment

Myeloid-derived suppressor cells (MDSCs) are key immunosuppressive cells in the tumor microenvironment (TME) that play critical roles in promoting tumor growth and metastasis. Tumor-associated platelets (TAPs) help cancer cells evade the immune system and promote metastasis. In this paper, we describe the interaction between MDSCs and TAPs, including their generation, secretion, activation, and recruitment, as well as the effects of MDSCs and platelets on the generation and changes in the immune, metabolic, and angiogenic breast cancer (BC) microenvironments. In addition, we summarize preclinical and clinical studies, traditional Chinese medicine (TCM) therapeutic approaches, and new technologies related to targeting and preventing MDSCs from interacting with TAPs to modulate the BC TME, discuss the potential mechanisms, and provide perspectives for future development. The therapeutic strategies discussed in this review may have implications in promoting the normalization of the BC TME, reducing primary tumor growth and distant lung metastasis, and improving the efficiency of anti-tumor therapy, thereby improving the overall survival (OS) and progression-free survival (PFS) of patients. However, despite the significant advances in understanding these mechanisms and therapeutic strategies, the complexity and heterogeneity of MDSCs and side effects of antiplatelet agents remain challenging. This requires further investigation in future prospective cohort studies.

Elevated 18F-FDG uptake in subcutaneous adipose tissue correlates negatively with nutritional status and prognostic survival in cachexia patients with gastric cancer

BACKGROUND

Browning of white adipose tissue is a crucial factor contributing to adipose loss in cachexia patients, detectable via 18F-Fluorodeoxyglucose (18F-FDG) uptake. The present study elucidates the clinical relevance of 18F-FDG uptake in the subcutaneous adipose tissue of gastric cancer patients, specifically focusing on adipose browning and its implications on patient clinical parameters and prognosis.

METHODS

This investigation encompassed 770 gastric cancer patients, with PET-CT imaging and clinical data meticulously combined. The 18F-FDG uptake in subcutaneous adipose tissue at the third lumbar layer was quantified, and its correlation with clinical parameters, particularly those related to nutritional status and fat metabolism, was examined. Kaplan-Meier curves were subsequently employed to probe the relationship between 18F-FDG uptake and overall survival.

RESULTS

Of the 770 gastric cancer patients, 252 exhibited cancer-associated cachexia, while 518 did not. Cachectic patients demonstrated elevated 18F-FDG uptake in subcutaneous adipose tissue relative to non-cachectic patients (P < 0.001). Increased 18F-FDG uptake was also correlated with reduced plasma concentrations of albumin, prealbumin, hemoglobin, platelets, cholesterol, apolipoprotein A, low-density lipoprotein, and elevated IL-6 concentrations (all P < 0.05). A significant inverse correlation was observed between 18F-FDG uptake and BMI, albumin, low-density lipoprotein, cholesterol, and apolipoprotein A (all P < 0.05). Patients with higher 18F-FDG uptake exhibited diminished overall survival rates compared to those with lower 18F-FDG uptake (P = 0.0065). Furthermore, 18F-FDG uptake in subcutaneous adipose tissue was an independent prognostic indicator in gastric cancer patients (P = 0.028).

CONCLUSIONS

Browning of subcutaneous adipose tissue was markedly elevated in cachectic gastric cancer patients compared to non-cachectic counterparts. Increased 18F-FDG uptake in subcutaneous adipose tissue in cachectic gastric cancer patients was inversely correlated with nutritional status and survival prognosis.

Predictive Value of NLR and PLR in Driver-Gene-Negative Advanced Non-Small Cell Lung Cancer Treated with PD-1/PD-L1 Inhibitors: A Single Institutional Cohort Study

OBJECTIVE

To investigate the predictive value of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) for the efficacy and prognosis of programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) inhibitors in driver-gene-negative advanced non-small-cell lung cancer (NSCLC).

METHODS

A retrospective analysis of 107 advanced NSCLC patients without gene mutations who received PD-1/PD-L1 inhibitors in our hospital from January 2020 to June 2022 was performed. NLR and PLR were collected before PD-1/PD-L1 inhibitors, the optimal cut-off values of NLR and PLR were determined according to the receiver operating characteristic (ROC) curve, and the effects of NLR and PLR on the efficacy of PD-1/PD-L1 inhibitors in advanced NSCLC patients were analyzed.

RESULTS

A total of 107 patients were included in this study. Receiver operating characteristic analysis showed that the optimal cut-off values of NLR and PLR were 3.825, 179, respectively. Kaplan-Meier curve showed that low baseline levels NLR and PLR were associated with an improvement in both progression-free survival (PFS) (P < .001, < .001, respectively) and overall survival (OS) (P = .009, .006, respectively). In first-line treatment and non-first-line treatment, low baseline levels NLR and PLR were associated with an improvement in PFS. In multivariate analysis, low baseline NLR and PLR showed a strong association with both better PFS (P = .011, .027, respectively) and longer OS (P = .042, .039, respectively).

CONCLUSION

Low baseline NLR and PLR levels are significantly associated with better response in advanced NSCLC patients treated with PD-1/PD-L1 inhibitors, which may be indicators to predict the efficacy of immunotherapy in advanced NSCLC with driver-gene-negative.

Predictive value of immunotherapy-induced inflammation indexes: dynamic changes in patients with nasopharyngeal carcinoma receiving immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs) have achieved substantial advancements in clinical care. However, there is no strong evidence for identified biomarkers of ICIs in NPC.

METHODS

In this retrospective study, 284 patients were enrolled into a training or validation cohort. Inflammatory indexes based on peripheral blood parameters were evaluated, including the systemic immune-inflammation index (SII), the neutrophil-lymphocyte ratio (NLR), the platelet-lymphocyte ratio (PLR), the lymphocyte-to-C-reactive protein ratio (LCR), and the lymphocyte-monocyte ratio (LMR). The optimum cut-off value for patient stratification was identified using X-tile. The Kaplan-Meier method and Cox's proportional regression analyses were used to identify prognostic factors.

RESULTS

Immunotherapy significantly changed the levels of SII, NLR, PLR, LCR and LMR in NPC patients. Patients with lower SII, NLR, and PLR, as well as those with higher LCR and LMR, before immunotherapy had superior PFS (all p < 0.05). Moreover, PFS in the decreased SII, reduced NLR and increased LMR group was significantly longer than in the opposite group (all p < 0.05). Both univariate and multivariate analyses validated that baseline SII and LMR, and the immunotherapy-related SII reduction and LMR elevation were independent prognostic factors for PFS in advanced NPC patients receiving ICIs.

CONCLUSIONS

Immune checkpoint inhibitor treatments significantly changed the levels of SII, NLR, PLR, LCR and LMR in NPC patients treated with immunotherapy. A lower baseline SII and a higher baseline LMR, and a reduction in SII and an elevation in LMR after immunotherapy are favorable factors for predicting survival among advanced NPC patients.

Effect of dynamic platelet-to-lymphocyte ratio on the prognosis of patients with esophageal squamous cell carcinoma receiving chemoradiotherapy

Systemic inflammatory load affects the long-term developmental outcomes in patients with malignancy. The purpose of this study was to investigate the effect of the dynamic levels of platelet-to-lymphocyte ratio (PLR) at different treatment stages on the prognosis of patients with esophageal squamous cell carcinoma (ESCC) undergoing chemoradiotherapy. This study included 168 patients who received chemoradiotherapy between 2012 and 2018. PLR levels at different treatment stages were calculated based on blood test results. The association between PLR and overall survival (OS) was determined using the Kaplan-Meier method and Cox proportional regression models. The cutoff values of PLR before and after treatment of 168 patients with ESCC were 195.7 and 403.6, respectively. The 5-year OS rates of patients in the low and high pre-PLR groups were 42.1% and 21.7%, respectively. The overall 5-year OS rate of all patients was 27.1%. Multivariate analysis results showed that patient age (hazard ratio [HR] = 1.736; 95% confidence interval (CI) = 1.129-2.669; P = .012), alcohol consumption (HR = 1.622; 95%CI = 1.050-2.508; P = .029), T stage (HR = 12.483; 95%CI = 3.719-41.896; P < .001), pre-PLR (HR = 1.716; 95%CI = 1.069-2.756; P = .025), post-PLR (HR = 1.664; 95%CI = 1.106-2.503; P = .015) were independent factors of the prognosis of patients with ESCC. PLR at different treatment stages can be used to effectively evaluate the prognosis of patients with ESCC undergoing chemoradiotherapy.

A practical prognostic peripheral blood-based risk model for the evaluation of the likelihood of a response and survival of metastatic cancer patients treated with immune checkpoint inhibitors

BACKGROUND

Less than half of unselected metastatic cancer patients benefit from the immune checkpoint inhibitor (ICI) therapy. Systemic cancer-related inflammation may influence the efficacy of ICIs and thus, systemic inflammatory markers could have prognostic and/or predictive potential in ICI therapy. Here, we aimed to identify a combination of inflammation-related laboratory parameters to establish a practical prognostic risk model for the pretreatment evaluation of a response and survival of ICI-treated patients with different types of metastatic cancers.

METHODS

The study-cohort consisted of a real-world patient population receiving ICIs for metastatic cancers of different origins (n = 158). Laboratory parameters determined before the initiation of the ICI treatment were retrospectively collected. Six inflammation-related parameters i.e., elevated values of neutrophils, platelets, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and lactate dehydrogenase (LDH), and the presence of anemia, were each scored with one point, giving 0-6 risk points for each patient. The patients with information of all these six parameters (n = 109) were then stratified into low-risk (0-3 points) and high-risk (4-6 points) groups. The overall response rate (ORR), overall survival (OS), and progression-free survival (PFS) according to the risk scores were determined.

RESULTS

The risk model was strongly associated with the outcome of the patients. The ORR to ICI treatment in the high-risk group was 30.3% in comparison to 53.9% in the low-risk group (p = 0.023). The medians for OS were 10.0 months and 27.3 months, respectively (p < 0.001), and the corresponding medians for PFS were 3.9 months and 6.3 months (p = 0.002). The risk group remained as a significant prognostic factor for both OS (HR 3.04, 95% CI 1.64-5.64, p < 0.001) and PFS (HR 1.79, 95% CI 1.04-3.06, p = 0.035) in the Cox multivariate analyses.

CONCLUSIONS

We propose a readily feasible, practical risk model consisted of six inflammation-related laboratory parameters as a tool for outcome prediction in metastatic cancer patients treated with ICIs. The risk model was strongly associated with the outcome of the patients in terms of all the evaluated indicators i.e., ORR, OS and PFS. Yet, further studies are needed to validate the risk model.

Peripheral blood inflammatory indexes in breast cancer: A review

Immune and inflammatory responses play an important role in tumorigenesis and metastasis. Inflammation is an important component of the tumor microenvironment, and the changes in inflammatory cells may affect the occurrence and development of tumors. Complete blood count at the time of diagnosis and treatment can reflect the inflammatory status within the tumor. Studies have shown that the number of certain inflammatory cells in peripheral blood and their ratios are important prognostic factors for many malignancies, including neutrophil, lymphocyte, monocyte, and platelet counts, as well as neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, systemic immune-inflammation index, systemic inflammation response index and pan-immune-inflammation-value. The value of peripheral blood inflammation indexes in predicting the efficacy and prognosis of breast cancer neoadjuvant therapy is worth recognizing. This review details the application of peripheral blood inflammation indexes in the evaluation of efficacy and prediction of prognosis in neoadjuvant therapy for breast cancer, aiming to provide a more comprehensive reference for the comprehensive diagnosis and treatment of breast cancer.

Laser-triggered intelligent drug delivery and anti-cancer photodynamic therapy using platelets as the vehicle

In our previous study, target drug delivery and treatment of malignant tumors have been achieved by using platelets as carriers loading nano-chemotherapeutic agents (ND-DOX). However, drug release from ND-DOX-loaded platelets is dependent on negative platelet activation by tumor cells, whose activation is not significant enough for the resulting drug release to take an effective anti-tumor effect. Exploring strategies to proactively manipulate the controlled release of drug-laden platelets is imperative. The present study innovatively revealed that photodynamic action can activate platelets in a spatiotemporally controlled manner. Consequently, based on the previous study, platelets were used to load iron oxide-polyglycerol-doxorubicin-chlorin e6 composites (IO-PG-DOX-Ce6), wherein the laser-triggered drug release ability and anti-tumor capability were demonstrated. The findings suggested that IO-PG-DOX-Ce6 could be stably loaded by platelets in high volume without any decrease in viability. Importantly and interestingly, drug-loaded platelets were significantly activated by laser irradiation, characterized by intracellular ROS accumulation and up-regulation of CD62p. Additionally, scanning electron microscopy (SEM) and hydrated particle size results also showed a significant aggregation response of laser irradiated-drug-loaded platelets. Further transmission electron microscopy (TEM) measurements indicated that the activated platelets released extracellularly their cargo drug after laser exposure, which could be taken up by co-cultured tumor cells. Finally, the co-culture model of drug-loaded platelets and tumor cells proved that laser-triggered delivery system of platelets could effectively damage the DNA and promote apoptosis of tumor cells. Overall, the present study discovers a drug-loaded platelets delivery using photodynamic effect, enabling laser-controlled intelligent drug delivery and anti-tumor therapy, which provides a novel and feasible approach for clinical application of cytopharmaceuticals.

Tumor cell-induced platelet aggregation accelerates hematogenous metastasis of malignant melanoma by triggering macrophage recruitment

BACKGROUND

Tumor cell-induced platelet aggregation (TCIPA) is not only a recognized mechanism for paraneoplastic thrombocytosis but also a potential breakthrough alternative for a low response to immune checkpoint inhibitors (ICIs) in hematogenous metastasis of malignant melanoma (MM). However, there is no TCIPA-specific model for further investigation of the relationship among TCIPA, the tumor immune microenvironment (TIME), and metastasis.

METHODS

We developed a TCIPA metastatic melanoma model with advanced hematogenous metastasis and enhanced TCIPA characteristics. We also investigated the pathway for TCIPA in the TIME.

RESULTS

We found that TCIPA triggers the recruitment of tumor-associated macrophages (TAMs) to lung metastases by secreting B16 cell-educated platelet-derived chemokines such as CCL2, SDF-1, and IL-1β. Larger quantities of TAMs in the TCIPA model were polarized to the M2 type by B16 cell reprocessing, and their surface programmed cell death 1 ligand 1 (PD-L1) expression was upregulated, ultimately assisting B16 cells in escaping host immunity and accelerating MM hematogenous metastasis.

CONCLUSIONS

TCIPA accelerates MM lung metastasis via tumor-educated platelets (TEPs), triggering TAM recruitment, promoting TAM polarization (M2), and remodeling the suppressive TIME in lung metastases.

[Analysis of efficacy and prognosis of neoadjuvant chemotherapy and （or） surgery plus radiotherapy for hypopharyngeal squamous cell carcinoma]

Objective:To analyze the risk factors that affect the prognosis of patients with hypopharyngeal squamous cell carcinoma（HPSCC） and to compare the efficacy of surgical resection followed by adjuvant radiotherapy（SR） with that of neoadjuvant therapy consisting of platinum-based chemotherapy and fluorouracil combined with either cetuximab or nimotuzumab, followed by SR. The study also aimed to evaluate the overall survival（OS） of patients, their postoperative eating function, tracheostomy decannulation rate, and tumor response to the two neoadjuvant chemotherapies. Methods:A retrospective analysis was performed on the medical records of HPSCC patients who received SR or neoadjuvant therapy followed by SR treatment at the Shanghai General Hospital from 2012 to 2019 and had not undergone any prior treatment. The prognostic factors were analyzed, and the survival analysis of patients who underwent SR treatment with two neoadjuvant chemotherapy regimens was performed. Results:A total of 108 patients were included in the study. The results of the univariate analysis showed that gender（P=0.850） had no significant correlation with the survival rate of HPSCC patients who underwent SR. However, age, smoking history, alcohol consumption history, platelet-to-lymphocyte ratio（PLR）, neutrophil-to-lymphocyte ratio（NLR）, T stage, N stage, neoadjuvant therapy with either cetuximab or nimotuzumab combined with platinum-based chemotherapy and fluorouracil, and histological grade were significantly associated with prognosis（P<0.05）. The multivariate analysis revealed that smoking history, histological grade, and neoadjuvant therapy with either cetuximab or nimotuzumab combined with platinum-based chemotherapy and fluorouracil were independent risk factors affecting the prognosis of HPSCC（P<0.05）. Patients who received neoadjuvant therapy had longer OS than those who underwent SR only（P<0.001）. There was no significant difference in tumor response to the two neoadjuvant therapies and in OS（P>0.05）, and there was no significant difference in the rate of oral feeding and tracheostomy decannulation among the three treatment groups（P>0.05）. Conclusion:Univariate analysis showed that age at tumor onset, smoking history, alcohol consumption history, NLR, PLR, T stage, N stage, whether receiving neoadjuvant chemotherapy, and pathological grade were associated with the prognosis of HPSCC patients receiving SR treatment. Multivariate analysis showed that smoking history, pathological grade, and neoadjuvant chemotherapy were independent risk factors affecting the prognosis. Neoadjuvant chemotherapy with cetuximab or nimotuzumab can prolong the OS of patients, providing a certain basis and reference for the treatment of HPSCC.

Tumor educated platelet: the novel BioSource for cancer detection

Platelets, involved in the whole process of tumorigenesis and development, constantly absorb and enrich tumor-specific substances in the circulation during their life span, thus called "Tumor Educated Platelets" (TEPs). The alterations of platelet mRNA profiles have been identified as tumor markers due to the regulatory mechanism of post-transcriptional splicing. Small nuclear RNAs (SnRNAs), the important spliceosome components in platelets, dominate platelet RNA splicing and regulate the splicing intensity of pre-mRNA. Endogenous variation at the snRNA levels leads to widespread differences in alternative splicing, thereby driving the development and progression of neoplastic diseases. This review systematically expounds the bidirectional tumor-platelets interactions, especially the tumor induced alternative splicing in TEP, and further explores whether molecules related to alternative splicing such as snRNAs can serve as novel biomarkers for cancer diagnostics.

Current Applications of Liquid Biopsy in Gastrointestinal Cancer Disease-From Early Cancer Detection to Individualized Cancer Treatment

Worldwide, gastrointestinal (GI) cancers account for a significant amount of cancer-related mortality. Tests that allow an early diagnosis could lead to an improvement in patient survival. Liquid biopsies (LBs) due to their non-invasive nature as well as low risk are the current focus of cancer research and could be a promising tool for early cancer detection. LB involves the sampling of any biological fluid (e.g., blood, urine, saliva) to enrich and analyze the tumor's biological material. LBs can detect tumor-associated components such as circulating tumor DNA (ctDNA), extracellular vesicles (EVs), and circulating tumor cells (CTCs). These components can reflect the status of the disease and can facilitate clinical decisions. LBs offer a unique and new way to assess cancers at all stages of treatment, from cancer screenings to prognosis to management of multidisciplinary therapies. In this review, we will provide insights into the current status of the various types of LBs enabling early detection and monitoring of GI cancers and their use in in vitro diagnostics.

Platelet Internalization Mediates Ferroptosis in Myocardial Infarction

BACKGROUND

Myocardial cell death is the hallmark of myocardial infarction. In the process of myocardial injury, platelets contribute to the pathogenesis by triggering intense inflammatory responses. Yet, it is still unclear if platelets regulate cardiomyocyte death directly, thereby exacerbating myocardial injury in myocardial infarction.

METHODS

We describe a mechanism underlying the correlative association between platelets accumulation and myocardial cell death by using myocardial infarction mouse model and patient specimens.

RESULTS

Myocardial infarction induces platelets internalization, resulting in the release of miR-223-3p, a platelet-enriched miRNA. By targeting the ACSL3, miR-223-3p delivered by internalized platelets cause the reduction of stearic acid-phosphatidylcholine in cardiomyocytes. The presence of stearic acid-phosphatidylcholine protects cardiomyocytes against ferroptosis.

CONCLUSIONS

Our work reveals a novel mechanism of platelet-mediated myocardial injury, highlighting antiplatelet therapies could potentially represent a multimechanism treatment of myocardial infarction, and implying ferroptosis being considered as novel target for therapeutics.

An Aspirin a Day: New Pharmacological Developments and Cancer Chemoprevention

Chemoprevention refers to the use of natural or synthetic agents to reverse, suppress, or prevent the progression or recurrence of cancer. A large body of preclinical and clinical data suggest the ability of aspirin to prevent precursor lesions and cancers, but much of the clinical data are inferential and based on descriptive epidemiology, case control, and cohort studies or studies designed to answer other questions (e.g., cardiovascular mortality). Multiple pharmacological, clinical, and epidemiologic studies suggest that aspirin can prevent certain cancers but may also cause other effects depending on the tissue or disease and organ site in question. The best-known biological targets of aspirin are cyclooxygenases, which drive a wide variety of functions, including hemostasis, inflammation, and immune modulation. Newly recognized molecular and cellular interactions suggest additional modifiable functional targets, and the existence of consensus molecular cancer subtypes suggests that aspirin may have differential effects based on tumor heterogeneity. This review focuses on new pharmacological developments and innovations in biopharmacology that clarify the potential role of aspirin in cancer chemoprevention.

The role of tumor-platelet interplay and micro tumor thrombi during hematogenous tumor metastasis

BACKGROUND

In addition to their pivotal roles in coagulation and thrombosis, platelets are crucial in tumor progression, with plenty of clinical and experimental data demonstrating that the interplay of platelets and tumor cells is essential for hematogenous tumor metastasis. After detach from primary sites, tumor cells intravasate into the blood circulation becoming circulating tumor cells and induce platelet activation, aggregation and encasement around tumor cells to form micro tumor thrombi, which create a permissive tumor microenvironment for metastasis. Platelets in micro tumor thrombi protect tumor cells from immune surveillance and anoikis (detachment-triggered apoptosis) through various pathways, which are significant for tumor cell survival in the bloodstream. Moreover, platelets can facilitate tumor metastasis by expediting epithelial-mesenchymal transition (EMT), adhesion to the endothelium, angiogenesis, tumor proliferation processes and platelet-derived microvesicle (PMV) formation.

CONCLUSIONS

Here, we provide a synopsis of the current understanding of the formation of micro tumor thrombi and the role of micro tumor thrombi in tumor hematogenous metastasis based on the tumor-platelet interplay. We also highlight potential therapeutic strategies targeting platelets for tumor treatment, including cancer-associated platelet-targeted nanomedicines.

Galectin functions in cancer-associated inflammation and thrombosis

Galectins are carbohydrate-binding proteins that regulate many cellular functions including proliferation, adhesion, migration, and phagocytosis. Increasing experimental and clinical evidence indicates that galectins influence many steps of cancer development by inducing the recruitment of immune cells to the inflammatory sites and modulating the effector function of neutrophils, monocytes, and lymphocytes. Recent studies described that different isoforms of galectins can induce platelet adhesion, aggregation, and granule release through the interaction with platelet-specific glycoproteins and integrins. Patients with cancer and/or deep-venous thrombosis have increased levels of galectins in the vasculature, suggesting that these proteins could be important contributors to cancer-associated inflammation and thrombosis. In this review, we summarize the pathological role of galectins in inflammatory and thrombotic events, influencing tumor progression and metastasis. We also discuss the potential of anti-cancer therapies targeting galectins in the pathological context of cancer-associated inflammation and thrombosis.

The role of tumor-educated platelets in ovarian cancer: A comprehensive review and update

Platelets have recently surfaced as critical players in cancer metastasis and the local and systemic responses to tumor growth. The emerging concept of "Tumor-educated platelets (TEPs)" comprises the exchange of biomolecules between tumor cells and platelets, thereby leading to the "education" of platelets. Increased platelet numbers have long been associated with cancer patients' tumor metastasis and poor clinical prognosis. However, it is very recently that researchers have delved deeper into the tumor-microenvironment and probed the mechanism of interactions between tumor cells and platelets. Designing strategies to target the TEPs and the communications between platelets and tumor cells can prove to be a promising breakthrough in cancer therapy. Through this review, we aim to analyze the recent developments in this field and discuss the characteristics of TEPs, focusing on ovarian cancer-associated TEPs and their characteristics, the interplay between ovarian cancer-associated TEPs and cancer cells, and the purview of TEP-targeted cancer diagnosis and therapy, including platelet biomarkers and inhibitors.

Human iPS Cells for Clinical Applications and Cellular Products

Human induced pluripotent stem cells (iPSCs), since their discovery in 2007, have rapidly become a starting cell type of choice for the differentiation of many mature cell types. Their flexibility, amenability to gene editing and functional equivalence to embryonic stem cells ensured their subsequent adoption by many manufacturing processes for cellular products. In this chapter, we will discuss the process whereby iPSCs are generated, key quality control steps which should be considered during manufacturing, the application of good manufacturing practice to production processes and iPSC-derived cellular products which are already undergoing clinical trials. iPSCs provide a new avenue for the next generation of cellular therapeutics and by combining new differentiation protocols, quality control and reproducible manufacturing, iPSC-derived cellular products could provide treatments for many currently untreatable diseases, allowing the large-scale manufacture of high-quality cell therapies.

Pretherapy platelet-to-lymphocyte ratio as a prognostic parameter for locally advanced hypopharyngeal cancer patients treated with radiotherapy combined with chemotherapy

PURPOSE

This study aimed to identify whether the platelet-to-lymphocyte ratio (PLR) correlated with the prognosis of patients with locally advanced hypopharyngeal squamous cell carcinoma (LA-HPSCC) undergoing radiotherapy combined with chemotherapy.

METHODS

This study enrolled 103 patients diagnosed with LA-HPSCC and treated with radiotherapy combined with chemotherapy between 2008 and 2021. The optimal PLR cut-off value was chosen from the receiver operating characteristic (ROC) curve analysis. According to the cut-off value of PLR, patients were divided into two groups: a low PLR group (< 133.06) and a high PLR group (≥ 133.06). Propensity score matching (PSM) was used to balance the confounding factors between the two PLR groups. Univariate and multivariate Cox proportional hazard regression models, the Kaplan-Meier curve by the log-rank test, and univariate and multivariate Fine-Gray competing risk models were all used for assessment.

RESULTS

After PSM, 27 pairs were left, and the high PLR group correlated with higher local failure (sHR 6.91, 95% CI 2.14-22.35, p = 0.001) in the multivariate Fine-Gray competing risk model. Moreover, the low PLR group had a significantly longer 3-year progression-free survival (43.7% vs. 29.2%, p = 0.038) and overall survival (55.1% vs. 32.1%, p = 0.034) than the high PLR group had. Multivariate Cox analysis showed that a low PLR was an independent protective factor for PFS (HR 0.43, 95% CI 0.21-0.92, p = 0.019) and OS (HR 0.46, 95% CI 0.22-0.96, p = 0.039) in patients with LA-HPSCC.

CONCLUSION

Pretherapy PLR might be a factor in predicting the risk of local failure and survival in LA-HPSCC patients undergoing radiotherapy combined with chemotherapy.

Burn-injured skin is marked by a prolonged local acute inflammatory response of innate immune cells and pro-inflammatory cytokines

The systemic and local immune response in burn patients is often extreme and derailed. As excessive inflammation can damage healthy tissues and slow down the healing process, modulation of inflammatory responses could limit complications and improve recovery. Due to its complexity, more detailed information on the immune effects of thermal injury is needed to improve patient outcomes. We therefore characterized and quantified subsets of immune cells and mediators present in human burn wound tissue (eschar), sampled at various time points. This study shows that after burn injury, the number of immune cells were persistently increased, unlike the normal wound healing process. There was an immediate, strong increase in neutrophils and a moderate increase in monocytes/macrophages and lymphocytes, especially in the second and third week post burn. The percentage of classical (CD14highCD16-) monocytes/macrophages demonstrated a steady decrease over time, whereas the proportion of intermediate (CD14highCD16+) monocytes/macrophages slowly increased. The absolute numbers of T cells, NK cells and B cells increased up to week 3, while the fraction of γδ T cells was increased only in week 1. Secretome profiling revealed high levels of chemokines and an overall pro-inflammatory cytokine milieu in burn tissue. The local burn immune response shows similarities to the systemic immune reaction, but differs in neutrophil maturity and lymphocyte composition. Altogether, the neutrophil surges, high levels of pro-inflammatory cytokines and limited immunosuppression might be key factors that prolong the inflammation phase and delay the wound healing process in burns.

Surgery-mediated tumor-promoting effects on the immune microenvironment

Surgical resection continues to be the mainstay treatment for solid cancers even though chemotherapy and immunotherapy have significantly improved patient overall survival and progression-free survival. Numerous studies have shown that surgery induces the dissemination of circulating tumor cells (CTCs) and that the resultant inflammatory response promotes occult tumor growth and the metastatic process by forming a supportive tumor microenvironment (TME). Surgery-induced platelet activation is one of the initial responses to a wound and the formation of fibrin clots can provide the scaffold for recruited inflammatory cells. Activated platelets can also shield CTCs to protect them from blood shear forces and promote CTCs evasion of immune destruction. Similarly, neutrophils are recruited to the fibrin clot and enhance cancer metastatic dissemination and progression by forming neutrophil extracellular traps (NETs). Activated macrophages are also recruited to surgical sites to facilitate the metastatic spread. More importantly, the body's response to surgical insult results in the recruitment and expansion of immunosuppressive cell populations (i.e. myeloid-derived suppressor cells and regulatory T cells) and in the suppression of natural killer (NK) cells that contribute to postoperative cancer recurrence and metastasis. In this review, we seek to provide an overview of the pro-tumorigenic mechanisms resulting from surgery's impact on these cells in the TME. Further understanding of these events will allow for the development of perioperative therapeutic strategies to prevent surgery-associated metastasis.

Prognostic role of the platelet to lymphocyte ratio (PLR) in the clinical outcomes of patients with advanced lung cancer receiving immunotherapy: A systematic review and meta-analysis

Background

It remains controversial whether the platelet to lymphocyte ratio (PLR) serves as a potential indicator for the efficacy of immunotherapy in advanced lung cancer. This meta-analysis aimed to address this concern.

Methods

Up to March 2022, we searched PubMed, Embase, Web of Science and the Cochrane Library to retrieve potentially eligible articles. Combined hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated to assess the relationship between PLR and progression-free survival (PFS) as well as overall survival (OS), while the combined odds ratios (ORs) and 95% CIs were estimated to evaluate the relationship between PLR and the objective response rate (ORR) as well as the disease control rate (DCR). Subgroup analyses were further performed to detect the source of heterogeneity and potential predictive value of PLR in different groups in terms of OS and PFS.

Results

A total of 21 included studies involving 2312 patients with advanced lung cancer receiving immunotherapy were included. The combined results suggested that elevated PLR was associated with poorer OS (HR=2.24; 95% CI: 1.87-2.68; I² =44%; P=0.01) and PFS (HR=1.66; 95% CI: 1.36-2.04; I² =64%; P<0.01). Furthermore, elevated PLR showed a lower ORR (OR= 0.61; 95% CI: 0.43-0.87, I²=20%; P=0.29) and DCR (OR= 0.44; 95% CI: 0.27-0.72, I²=61%; P=0.02). In subgroup analyses, pretreatment PLR was significantly associated with adverse OS and PFS. The same results were observed in different PLRs in terms of cutoff value (>200 vs. ≤200). Furthermore, high PLR was significantly associated with poor OS and PFS in advanced non-small cell lung cancer (NSCLC); however, PLR was not associated with OS and PFS in advanced small cell lung cancer (SCLC). In addition, PLR predicted poor OS irrespective of regions and types of immune checkpoint inhibitors (ICIs).

Conclusion

On the whole, patients with low PLR had better OS and PFS, as well as higher ORR and DCR when receiving immunotherapy in advanced lung cancer especially for advanced NSCLC. And further investigations are warranted to confirm the prognostic value of PLR in advanced SCLC.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022315976.

Genus Spatholobus: a comprehensive review on ethnopharmacology, phytochemistry, pharmacology, and toxicology

Edible medicinal plants are important sources for the development of health beneficial products and drugs. Several species of the genus Spatholobus are considered as medicinal and food homologous plants in various Asian countries for the treatment of menstrual pain, anemia, paralysis, arthralgia, etc. Regarding this genus, mounting investigations on different aspects have been conducted; however, a comprehensive review about these findings is yet to be compiled. Herein, we reviewed the up-to-date information on the botanical description, distribution, ethnopharmacology, phytochemistry, pharmacology, and toxicology of the Spatholobus species for the first time to support their development potential. Thus far, 175 phytochemicals have been isolated, and flavonoids are the predominant constituents. Furthermore, 141 compounds show the ideal characteristic behavior of a drug-like molecule. Besides, the compounds and crude extracts of this genus have been demonstrated to exert a wide range of in vitro and in vivo bioactivities, such as antitumor activity, antioxidant activity, antiinflammatory activity, antiischemic activity, antimicrobial activity, and neuroprotective activity. Toxicity studies have revealed that Spatholobus species seem to have no apparent toxic effects. Even so, the need for in-depth studies to reveal the scientific connotation of the widely documented traditional actions, the structure-activity relationship of the bioactive compounds, and the systematic toxic reactions are warranted, and also to provide essential evidence for the beneficial use of Spatholobus plants and developing novel health care products and therapeutic drug from this genus.

Novel Markers for Liquid Biopsies in Cancer Management: Circulating Platelets and Extracellular Vesicles

Although radiologic imaging and histologic assessment of tumor tissues are classic approaches for diagnosis and monitoring of treatment response, they have many limitations. These include challenges in distinguishing benign from malignant masses, difficult access to the tumor, high cost of the procedures, and tumor heterogeneity. In this setting, liquid biopsy has emerged as a potential alternative for both diagnostic and monitoring purposes. The approaches to liquid biopsy include cell-free DNA/circulating tumor DNA, long and micro noncoding RNAs, proteins/peptides, carbohydrates/lectins, lipids, and metabolites. Other approaches include detection and analysis of circulating tumor cells, extracellular vesicles, and tumor-activated platelets. Ultimately, reliable use of liquid biopsies requires bioinformatics and statistical integration of multiple datasets to achieve approval in a Clinical Laboratory Improvement Amendments setting. This review provides a balanced and critical assessment of recent discoveries regarding tumor-derived biomarkers in liquid biopsies along with the potential and pitfalls for cancer detection and longitudinal monitoring.

Interplay between Comprehensive Inflammation Indices and Redox Biomarkers in Testicular Germ-Cell Tumors

Sustained and dysregulated inflammation, concurrent tumor-induced immune suppression, and oxidative stress are profoundly involved in cancer initiation, presentation, and perpetuation. Within this prospective study, we simultaneously analyzed the preoperative indices of systemic inflammatory response and the representative byproducts of oxidative DNA, protein, and lipid damage with the aim of evaluating their clinical relevance among patients diagnosed with testicular germ-cell tumors (GCT). In the analytical cohort (n = 88, median age 34 years), neutrophil-to-lymphocyte ratio (NLR), derived neutrophil-to-lymphocyte ratio (dNLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), and C-reactive protein (CRP) were significantly altered in patients with a higher tumor stage (p < 0.05). Highly suggestive correlations were found between NLR, dNLR, and SII and modified nucleoside 8-OHdG. CRP and albumin-to-globulin ratio (AGR) significantly correlated with thiols group level and maximal tumor dimension (p < 0.05). Based on receiver operating characteristic (ROC) curve analyses, all the evaluated pre-orchiectomy inflammation markers demonstrated strong performance in predicting metastatic disease; optimal cut-off points were determined for each indicator. Although further large-scale studies are warranted, inflammatory and redox indices may both complement the established tumor markers and standard clinicopathological prognostic variables and contribute to enhanced personalized risk-assessment among testicular GCT patients.

Chitin/corn stalk pith sponge stimulated hemostasis with erythrocyte absorption, platelet activation, and Ca2+-binding capabilities

Chitin (CT) is widely used as a hemostatic material in surgical sponges, although its efficacy needs improvement to promote the clotting process. In this study, another green biomass, corn stalk pith (CSP), was incorporated into CT through ball milling to fabricate CT-CSP composite hemostatic sponges to enhance erythrocyte absorption, platelet activation, and clotting factor accumulation (Ca²⁺). In vitro hemostatic analysis indicated that CSP incorporation greatly promoted the coagulation process, with a much lower blood clot index and higher blood clot stability. In addition, the composite sponge promoted more platelet adhesion and activation, and the composite sponge demonstrated a greater ability to bind clotting factors (Ca²⁺). Consistently, it achieved complete hemostasis with less blood loss and a shorter hemostatic time in a rat liver injury-model. This composite hemostatic sponge is sustainable, cost-efficient, and biocompatible, which highlight the excellent translational potential in clinical settings.

Possible Neoplastic or Proliferative Effects of Intra-Tympanic Platelet-Rich Plasma on the MiddleEarMucosa: A Myth or a Fact to Consider?

BACKGROUND

Platelet-rich plasma is a frequently used plasma-derived material; however, a possible neoplastic or proliferative effect is one of the limiting issues in its use. The aim of our experimental study was to investigate the long-term histological effects of platelet-rich plasma on the middle ear mucosa.

METHODS

The rats were divided into 2 groups randomly (groups 1 and 2). Group 1 represented the control group and 8 rats were included in this group. To the left ear, 0.3 mL of normal saline solution was administered intra-tympanically. No injections were done to the right ears. Group 2 represented the platelet-rich plasma group and 11 rats were included. To the left ears, 0.3 mL of platelet-rich plasma and to the right ears 0.3 mL of normal saline solution was administered intra-tympanically. The intra-tympanic platelet-rich plasma injections were done twice with an interval of 1 week. All animals were sacrificed in the third month. The degree of mucosal thickness, the presence of metaplasia, atypical cells, myofibroblastic infiltration, angiogenesis, and acute or chronic inflammation were evaluated histopathologically.

RESULTS

Histopathological findings in the right and left ears in each group were compared in itself. The degree of inflammation and mucosal thickness were significantly higher in the perforated and saline administered side, in group 1 (P < .001). In group 2, the degree of angiogenesis was significantly higher in the platelet-rich plasma administered side (P < .001). The degree of mucosal thickness was significantly higher in the saline administered side (P < .001).

CONCLUSION

Considering the anti-inflammatory and regenerative features and its safety, intra-tympanic-PRP may, in the future, be an alterna- tive to current intra-tympanic treatment modalities.

Depletion of tumor associated macrophages enhances local and systemic platelet-mediated anti-PD-1 delivery for post-surgery tumor recurrence treatment

Immunosuppressive cells residing in the tumor microenvironment, especially tumor associated macrophages (TAMs), hinder the infiltration and activation of T cells, limiting the anti-cancer outcomes of immune checkpoint blockade. Here, we report a biocompatible alginate-based hydrogel loaded with Pexidartinib (PLX)-encapsulated nanoparticles that gradually release PLX at the tumor site to block colony-stimulating factor 1 receptors (CSF1R) for depleting TAMs. The controlled TAM depletion creates a favorable milieu for facilitating local and systemic delivery of anti-programmed cell death protein 1 (aPD-1) antibody-conjugated platelets to inhibit post-surgery tumor recurrence. The tumor immunosuppressive microenvironment is also reprogrammed by TAM elimination, further promoting the infiltration of T cells into tumor tissues. Moreover, the inflammatory environment after surgery could trigger the activation of platelets to facilitate the release of aPD-1 accompanied with platelet-derived microparticles binding to PD-1 receptors for re-activating T cells. All these results collectively indicate that the immunotherapeutic efficacy against tumor recurrence of both local and systemic administration of aPD-1 antibody-conjugated platelets could be strengthened by local depletion of TAMs through the hydrogel reservoir.

Increased density of tumor associated macrophages has been correlated with tumor recurrence following surgery. Here the authors design an alginate-based hydrogel encapsulating anti-PD-1-conjugated platelets and nanoparticles loaded with the macrophage-depleting CSF-1R inhibitor pexidartinib, showing inhibition of post-surgery tumor recurrence in preclinical models.

Of vascular defense, hemostasis, cancer, and platelet biology: an evolutionary perspective

We have established considerable expertise in studying the role of platelets in cancer biology. From this expertise, we were keen to recognize the numerous venous-, arterial-, microvascular-, and macrovascular thrombotic events and immunologic disorders are caused by severe, acute-respiratory-syndrome coronavirus 2 (SARS-CoV-2) infections. With this offering, we explore the evolutionary connections that place platelets at the center of hemostasis, immunity, and adaptive phylogeny. Coevolutionary changes have also occurred in vertebrate viruses and their vertebrate hosts that reflect their respective evolutionary interactions. As mammals adapted from aquatic to terrestrial life and the heavy blood loss associated with placentalization-based live birth, platelets evolved phylogenetically from thrombocytes toward higher megakaryocyte-blebbing-based production rates and the lack of nuclei. With no nuclei and robust RNA synthesis, this adaptation may have influenced viral replication to become less efficient after virus particles are engulfed. Human platelets express numerous receptors that bind viral particles, which developed from archetypal origins to initiate aggregation and exocytic-release of thrombo-, immuno-, angiogenic-, growth-, and repair-stimulatory granule contents. Whether by direct, evolutionary, selective pressure, or not, these responses may help to contain virus spread, attract immune cells for eradication, and stimulate angiogenesis, growth, and wound repair after viral damage. Because mammalian and marsupial platelets became smaller and more plate-like their biophysical properties improved in function, which facilitated distribution near vessel walls in fluid-shear fields. This adaptation increased the probability that platelets could then interact with and engulf shedding virus particles. Platelets also generate circulating microvesicles that increase membrane surface-area encounters and mark viral targets. In order to match virus-production rates, billions of platelets are generated and turned over per day to continually provide active defenses and adaptation to suppress the spectrum of evolving threats like SARS-CoV-2.

Thy-1 (CD90), Integrins and Syndecan 4 are Key Regulators of Skin Wound Healing

Acute skin wound healing is a multistage process consisting of a plethora of tightly regulated signaling events in specialized cells. The Thy-1 (CD90) glycoprotein interacts with integrins and the heparan sulfate proteoglycan syndecan 4, generating a trimolecular complex that triggers bi-directional signaling to regulate diverse aspects of the wound healing process. These proteins can act either as ligands or receptors, and they are critical for the successful progression of wound healing. The expression of Thy-1, integrins, and syndecan 4 is controlled during the healing process, and the lack of expression of any of these proteins results in delayed wound healing. Here, we review and discuss the roles and regulatory events along the stages of wound healing that support the relevance of Thy-1, integrins, and syndecan 4 as crucial regulators of skin wound healing.

Platelet Membrane: An Outstanding Factor in Cancer Metastasis

In addition to being biological barriers where the internalization or release of biomolecules is decided, cell membranes are contact structures between the interior and exterior of the cell. Here, the processes of cell signaling mediated by receptors, ions, hormones, cytokines, enzymes, growth factors, extracellular matrix (ECM), and vesicles begin. They triggering several responses from the cell membrane that include rearranging its components according to the immediate needs of the cell, for example, in the membrane of platelets, the formation of filopodia and lamellipodia as a tissue repair response. In cancer, the cancer cells must adapt to the new tumor microenvironment (TME) and acquire capacities in the cell membrane to transform their shape, such as in the case of epithelial−mesenchymal transition (EMT) in the metastatic process. The cancer cells must also attract allies in this challenging process, such as platelets, fibroblasts associated with cancer (CAF), stromal cells, adipocytes, and the extracellular matrix itself, which limits tumor growth. The platelets are enucleated cells with fairly interesting growth factors, proangiogenic factors, cytokines, mRNA, and proteins, which support the development of a tumor microenvironment and support the metastatic process. This review will discuss the different actions that platelet membranes and cancer cell membranes carry out during their relationship in the tumor microenvironment and metastasis.

A Novel Platelet-Related Gene Signature for Predicting the Prognosis of Triple-Negative Breast Cancer

Regarded as the most invasive subtype, triple-negative breast cancer (TNBC) lacks the expression of estrogen receptors (ERs), progesterone receptors (PRs), and human epidermal growth factor receptor 2 (HER2) proteins. Platelets have recently been shown to be associated with metastasis of malignant tumors. Nevertheless, the status of platelet-related genes in TNBC and their correlation with patient prognosis remain unknown. In this study, the expression and variation levels of platelet-related genes were identified and patients with TNBC were divided into three subtypes. We collected cohorts from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. By applying the least absolute shrinkage and selection operator (LASSO) Cox regression method, we constructed a seven-gene signature which classified the two cohorts of patients with TNBC into low- or high-risk groups. Patients in the high-risk group were more likely to have lower survival rates than those in the low-risk group. The risk score, incorporated with the clinical features, was confirmed as an independent factor for predicting the overall survival (OS) time. Functional enrichment analyses revealed the involvement of a variety of vital biological processes and classical cancer-related pathways that could be important to the ultimate prognosis of TNBC. We then built a nomogram that performed well. Moreover, we tested the model in other cohorts and obtained positive outcomes. In conclusion, platelet-related genes were closely related to TNBC, and this novel signature could serve as a tool for the assessment of clinical prognosis.

Uptake of platelets by cancer cells and recycling of the platelet protein CD42a

BACKGROUND

It is well accepted that the bidirectional crosstalk between platelets and cancer cells promotes tumorigenesis and metastasis. In an early step, cancer cells trigger platelet granule and extracellular vesicle release that is needed to facilitate cancer cell survival in circulation.

OBJECTIVES

To discover the early crosstalk of cancer cells and platelets.

METHODS

Cancer cells were incubated with freshly isolated and stained human platelets. Confocal laser scanning microscopy and flow cytometry was used to visualize and to quantify platelet uptake and the membrane presence of CD42 on cancer cells. Dyngo4a was used to test if platelet uptake is a dynamin-dependent process.

RESULTS

We found a dynamin-dependent uptake of platelets by cancer cells. This is followed by the recycling of the platelet-specific protein CD42a and its incorporation into cancer cells' plasma membrane, which is not a result of platelet RNA transfer by platelet-derived microparticles and exosomes. Time course of platelet uptake follows a sigmoid function revealing that 50% of the cancer cells are positive for platelets after approximately 38 min. Platelet uptake was observed for the tested cancerous cells (A549, MCF-7, and MV3) but not for the non-cancerous cell line 16HBE14o-.

CONCLUSIONS

Our results demonstrate that cancer cells hijack platelets by phagocytosis and recycling of platelet membrane proteins. The uptake of platelets has additional advantages for cancer cells: access to the entire and undiluted platelet proteome, transcriptome, and secretome. These novel findings will allow further mechanistic elucidation and thus help us gain deeper insights into platelet-assisted hematogenous metastasis.

Identification of gene signature in RNA-Seq hepatocellular carcinoma data by Pareto-optimal cluster algorithm

Aim

This study aimed to detect gene signatures in RNA-sequencing (RNA-seq) data using Pareto-optimal cluster size identification.

Background

RNA-seq has emerged as an important technology for transcriptome profiling in recent years. Gene expression signatures involving tens of genes have been proven to be predictive of disease type and patient response to treatment.

Methods

Data related to the liver cancer RNA-seq dataset, which included 35 paired hepatocellular carcinoma (HCC) and non-tumor tissue samples, was used in this study. The differentially expressed genes (DEGs) were identified after performing pre-filtering and normalization. After that, a multi-objective optimization technique, namely multi-objective optimization for collecting cluster alternatives (MOCCA), was used to discover the Pareto-optimal cluster size for these DEGs. Then, the k-means clustering method was performed on the RNA-seq data. The best cluster, as a signature for the disease, was found by calculating the average Spearman's correlation score of all genes in the module in a pair-wise manner. All analyses were performed in the R 4.1.1 package in virtual space with 100 Gb of RAM memory.

Results

Using MOCCA, eight Pareto-optimal clusters were obtained. Ultimately, two clusters with the greatest average Spearman's correlation coefficient scores were chosen as gene signatures. Eleven prognostic genes involved in HCC's abnormal metabolism were identified. In addition, three differentially expressed pathways were identified between tumor and non-tumor tissues.

Conclusion

These identified metabolic prognostic genes help us to provide more powerful prognostic information and enhance survival prediction for HCC patients. In addition, Pareto-optimal cluster size identification is suggested for gene signature in other RNA-Seq data.

Systemic Immune Activation and Responses of Irradiation to Different Metastatic Sites Combined With Immunotherapy in Advanced Non-Small Cell Lung Cancer

Purpose

Considering the limited data, we aimed to identify the greatest immune activation irradiated site of common metastases and response to immune checkpoint inhibitors simultaneously in non-small cell lung cancer (NSCLC).

Methods

A total of 136 patients with advanced NSCLC who had received radiation to a primary or metastatic solid tumor were enrolled. We recorded blood cell counts in three time periods, before, during, and after radiotherapy (RT), and derived some blood index ratios including monocyte-to-lymphocyte ratio (MLR), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII). The delta-IBs were calculated as medio-IBs ÷ pre-IBs − 1. We analyzed the changes before and during RT using Spearman rank correlation test, Kruskal–Wallis rank sum test, and logistic regression analyzing their correlation with efficacy.

Results

The medians of delta-MLR and delta-PLR were both the lowest while the median of delta-L was the highest in brain. Therapeutic effect evaluation showed that the objective response rate (ORR) of 48.65% (18/37) in the brain irradiation group was the highest, compared with 17.07% (7/41) in bone and 41.94% (13/31) in lung.

Conclusions

In this study, results suggested that irradiation to brain has the best immune activation effect and patient outcome compared with other organs in NSCLC, and when the earlier-line ICIs were combined with RT, a better patient outcome was reached. Prospective studies are also necessary to provide more convincing evidence and standards for clinical irradiation metastases selection.

A prediction model for acute respiratory distress syndrome among patients with severe acute pancreatitis: a retrospective analysis

Background:

Acute respiratory distress syndrome (ARDS) is a severe complication among patients with severe acute pancreatitis (SAP), which may be associated with increased mortality in hospitalized patients. Thus, an effective model to predict ARDS in patients with SAP is urgently required.

Methods:

We retrospectively analyzed the data from the patients with SAP who recruited in Xiangya Hospital between April 2017 and May 2021. Patients meeting the Berlin definition of ARDS were categorized into the ARDS group. Logistic regression models and a nomogram were utilized in the study. Descriptive statistics, logistic regression models, and a nomogram were used in the current study.

Results:

Comorbidity of ARDS occurred in 109 (46.58%) of 234 patients with SAP. The SAP patients with ARDS group had a higher 60-day mortality rate, an increased demand for invasive mechanical ventilation, and a longer intensive care unit (ICU) stay than those without ARDS (p < .001 for all). Partial pressure of oxygen (PaO2): fraction of inspired oxygen (FiO2) < 200, platelets <125 × 109/L, lactate dehydrogenase >250 U/L, creatinine >111 mg/dL, and procalcitonin >0.5 ng/mL were independent risk variables for development of ARDS in SAP patients. The area under the curve for the model was 0.814, and the model fit was acceptable [p = .355 (Hosmer–Lemeshow)]. Incorporating these 5 factors, a nomogram was established with sufficient discriminatory power (C-index 0.814). Calibration curve indicated the proper discrimination and good calibration in the predicting nomogram model.

Conclusion:

The prediction nomogram for ARDS in patients with SAP can be applied using clinical common variables after the diagnosis of SAP. Future studies would be warranted to verify the potential clinical benefits of this model.

The Ratio of Platelets to Lymphocytes Predicts the Prognosis of Metastatic Colorectal Cancer: A Review and Meta-Analysis

BACKGROUND

In recent years, the incidence of colorectal cancer (CRC) has continued to increase. Although the overall prognosis of CRC has improved with the continuous improvement of the level of treatment, the prognosis of metastatic colorectal cancer (mCRC) is still poor. The purpose of our study is to explore the prognostic value of platelet to lymphocyte ratio (PLR) in mCRC.

METHODS

The PubMed, Web of Science, and Embase (via OVID) were systematically searched to obtain all relevant research. We used hazard ratio (HR) with 95% confidence interval (CI) to assess the associations of PLR and overall survival (OS) and progression free survival (PFS).

RESULTS

A total of twelve studies containing 1452 patients were included in this meta-analysis. Pooled analysis showed that high levels of PLR were associated with poor OS (HR: 1.72, 95% CI: 1.27-2.33, and P < 0.01) and PFS (HR: 1.64, 95% CI: 1.16-2.31, and P = 0.033).

CONCLUSION

Our analysis suggested that high levels of PLR pretreatment may be an effective predictive biomarker for the prognosis of mCRC patients.

Bidirectional Interaction Between Cancer Cells and Platelets Provides Potential Strategies for Cancer Therapies

Platelets are essential components in the tumor microenvironment. For decades, clinical data have demonstrated that cancer patients have a high risk of thrombosis that is associated with adverse prognosis and decreased survival, indicating the involvement of platelets in cancer progression. Increasing evidence confirms that cancer cells are able to induce production and activation of platelets. Once activated, platelets serve as allies of cancer cells in tumor growth and metastasis. They can protect circulating tumor cells (CTCs) against the immune system and detachment-induced apoptosis while facilitating angiogenesis and tumor cell adhesion and invasion. Therefore, antiplatelet agents and platelet-based therapies should be developed for cancer treatment. Here, we discuss the mechanisms underlying the bidirectional cancer-platelet crosstalk and platelet-based therapeutic approaches.

Healing through the lens of immunothrombosis: Biology-inspired, evolution-tailored, and human-engineered biomimetic therapies

Evolution, from invertebrates to mammals, has yielded and shaped immunoclotting as a defense and repair response against trauma and infection. This mosaic of immediate and local wound-sealing and pathogen-killing mechanisms results in survival, restoration of homeostasis, and tissue repair. In mammals, immunoclotting has been complemented with the neuroendocrine system, platelets, and contact system among other embellishments, adding layers of complexity through interconnecting blood-born proteolytic cascades, blood cells, and the neuroendocrine system. In doing so, immunothrombosis endows humans with survival advantages, but entails vulnerabilities in the current unprecedented and increasingly challenging environment. Immunothrombosis and tissue repair appear to go hand in hand with common mechanisms mediating both processes, a fact that is underlined by recent advances that are deciphering the mechanisms of the repair process and of the biochemical pathways that underpins coagulation, hemostasis and thrombosis. This review is intended to frame both the universal aspects of tissue repair and the therapeutic use of autologous fibrin matrix as a biology-as-a-drug approach in the context of the evolutionary changes in coagulation and hemostasis. In addition, we will try to shed some light on the molecular mechanisms underlying the use of the autologous fibrin matrix as a biology-inspired, evolution-tailored, and human-engineered biomimetic therapy.

Plasminogen activator receptor assemblies in cell signaling, innate immunity, and inflammation

Tissue-type plasminogen activator (tPA) and urokinase-type plasminogen activator (uPA) are serine proteases and major activators of fibrinolysis in mammalian systems. Because fibrinolysis is an essential component of the response to tissue injury, diverse cells, including cells that participate in the response to injury, have evolved receptor systems to detect tPA and uPA and initiate appropriate cell-signaling responses. Formation of functional receptor systems for the plasminogen activators requires assembly of diverse plasma membrane proteins, including but not limited to: the urokinase receptor (uPAR); integrins; N-formyl peptide receptor-2 (FPR2), receptor tyrosine kinases (RTKs), the N-methyl-d-aspartate receptor (NMDA-R), and low-density lipoprotein receptor-related protein-1 (LRP1). The cell-signaling responses elicited by tPA and uPA impact diverse aspects of cell physiology. This review describes rapidly evolving knowledge regarding the structure and function of plasminogen activator receptor assemblies. How these receptor assemblies regulate innate immunity and inflammation is then considered.

Where is Waldo? or find the platelet

Platelets evolved from nucleated thrombocytes that exhibit both coagulation and immune function. The essential role of platelets in coagulation is common knowledge. The larger and critical role of platelets in immune responses and cancer are frequently overlooked in our modern-day, large-data-set, sequencing-oriented efforts. Much like Waldo, their small size, biophysical characteristics, rapid biological responses, active cytoskeleton, migration capacity, and lack of a nucleus make them difficult to track as single platelets disappear while executing their function into the histologic "tissue scape". The adaptive evolution of platelets is linked to placentalization and stopping massive blood loss. This resulted in exclusion of any platelet nucleus and therefore sustainable gene expression due to being extruded in the billions (1011) per day from megakaryocytes under bone marrow protection. The platelets' small size and sheer number in circulation, combined with an active open canalicular exchange- and membrane-reserve system, plus an array of pathogen receptors enable them to deal with small pathogenic viral treats and to decorate larger ones for further immune identification and immune-cell recruitment. Once stimulated, platelets release most serum-based cytokines and growth factors that contribute to cell growth and wound repair, and potentially to immune suppression. From a self-taught practitioner of the illustrative arts with a ken for platelet biology, this offering is a humble attempt to provide a stimulating sketch of the critical importance of platelet biology and insights into potential new directions for finding the Waldo-esque platelet.