Heparin and cancer revisited: mechanistic connections involving platelets, P-selectin, carcinoma mucins, and tumor metastasis

Transcriptomic and functional characterization of megakaryocytic-derived platelet-like particles: impaired aggregation and prominent anti-tumor effects

Platelet-like particles (PLPs), derived from megakaryocytic cell lines MEG-01 and K-562, are widely used as a surrogate to study platelet formation and function. We demonstrate by RNA-Seq that PLPs are transcriptionally distinct from platelets. Expression of key genes in signaling pathways promoting platelet activation/aggregation, such as the PI3K/AKT, protein kinase A, phospholipase C, and α-adrenergic and GP6 receptor pathways, was missing or under-expressed in PLPs. Functionally, PLPs do not aggregate following epinephrine, collagen, or ADP stimulation. While PLPs aggregated in response to thrombin, they did not display enhanced expression of surface markers P-selectin and activated α2bβ3, in contrast to platelets. We have previously demonstrated that platelets physically couple to MDA-PCa-2b and RC77T/E prostate cancer (PCa) cells via specific ligand-receptor interactions, leading to platelet-stimulated cell invasiveness and apoptotic resistance, and reciprocal cell-induced platelet aggregation. In contrast, PLP interactions with PCa cells inhibited both cell invasion and apoptotic resistance while failing to promote PLP aggregation. Moreover, PLPs reduced platelet-PCa cell interactions and antagonized platelet-stimulated oncogenic effects in PCa cells. RNA-Seq analysis identified candidate ligand-transmembrane protein combinations involved in anti-tumorigenic signaling of PLPs to PCa cells. Antibody neutralization of the TIMP3-MMP15 and VEGFB-FGFR1 signaling axes reversed PLP-mediated anti-invasion and apoptotic sensitization, respectively. In summary, PLPs lack many transcriptomic, molecular and functional features of platelets and possess novel anti-tumorigenic properties. These findings indicate that PLPs may have a potential therapeutic role in targeting and disrupting the oncogenic signaling between platelets and cancer cells, offering a new avenue for anti-cancer strategies.

Iron Oxide Nanoparticles as Enhancers for Radiotherapy of Tumors

This research aimed to evaluate the potency of preparation based on heparinized iron oxide nanoparticles (hIONPs) in combination with radiation therapy, including magnetic delivery via the applied magnetic field (AMF), in sarcoma and cervical cancer models. For in vitro studies, cells of rhabdomyosarcoma (RD), fibrosarcoma (HT1080), and cervical cancer (HeLa S3) were treated with hIONPs and analyzed for survival rate and hIONP uptake. Then, cell morphology, cell cycle, increase of reactive oxygen species, mitochondria depolarization, and ability to form colonies were assessed for combined treatment (hIONPs + 3Gy). For in vivo research, hIONPs were administered once in the hybrids of CBAxC57Bl/6j mice, grafted with sarcoma (S37) and cervical cancer (CC5) strains. The ultimate in vivo treatment modes were: (1) i.v. hIONPs (14 μg/kg) + 5 Gy; (2) i.v. hIONPs (14 μg/kg) + AMF + 5 Gy; and (3) i.t. hIONPs (2,8 μg/kg) + 5 Gy. The overall survival rates, increase in life expectancy, inhibition of tumor growth (tumor growth inhibition), and degree of inhibition (T/C) were determined, and pathomorphological changes were assessed in experimental groups. The combined treatment in vitro (hIONPs + 3Gy) promotes multiple tumor cell death with high-severity peroxide effects compared with other groups. The sarcoma cells were more sensitive than cervical cancer cells. For in vivo, an enhancing effect was revealed by the combination of radiotherapy and magnetic-delivered hIONPs. For S37 tumor, the treatment regimen was characterized as having a high antitumor effect, ≪++++ ≫, with a 20% cure rate of mice. For the CC5 tumor, the effect was accompanied by the inhibition of tumor growth, an increase in the life expectancy of animals, and was characterized as a significant antitumor effect, ≪+++/++ ≫. From the data obtained, it can be concluded that the radiosensitizing potential of hIONPs may be taken as a basis of combined radiation treatment protocols.

A parametric study of motion and attachment to capillary walls of circulating tumor cells (CTCs) interacting with non-activated and activated platelets

BACKGROUND AND OBJECTIVE

Our previous research examined the biophysical conditions required for CTC arrest using a custom-built solid-fluid 2D axisymmetric computational model. Application of that model resulted in calculating the limiting conditions under which a CTC can pass through a narrowed capillary with a platelet attached to the capillary wall. This paper is a step forward in determining the effects of a selected set of parameters: number of platelets, CTC diameter, stiffness, and ligand-receptor bond stiffness of the CTC (with or without attached platelets) on the CTC trajectory, its axial position, and its attachment to the wall. Consideration of a single CTC provides the "net" effects of platelets on CTC attachment, although, in reality, there can be many configurations of cells and platelets, leading to additional interactions and outcomes regarding metastasis. We consider cases where platelets are resting and when they are activated. The effects of platelet activation on cell attachment to the wall-and hence on metastasis-are among the main goals of this paper. Quantification of platelet activation is achieved through an original concept that connects our computational model with data from a unique experimental investigation. The selected parameters provide METHODS: : The modeling concept of the motion of the CTC and platelets within the fluid relies on a strong coupling approach with a remeshing procedure. Additionally, a 1D FE truss (rope) element is implemented to simulate active ligand-receptor bonds, including the correction of platelet-cell adhesion forces due to platelet activation, as determined experimentally.

RESULTS

We have experimentally determined the attractive forces between cells and both non-activated and thrombin-activated platelets. The experimental results are incorporated into our computational models. This parametric study provides insight into the biomechanical conditions for CTC motion and arrest, contributing to the predictive capabilities for metastasis initiation and progression. Relationships are established between the properties of CTCs (size and stiffness), platelet size and stiffness, and ligand-receptor interaction intensity on one side, and the time in contact between CTCs and platelets, as well as the conditions for cell arrest, on the other side.

CONCLUSIONS

It is found that the number of platelets enhances the adhesion of the CTC to the wall due to effects on the fluid flow field and the overall increase in adhesion force with a higher number of platelets. Furthermore, it was found that adherence (metastasis), under otherwise identical conditions, is enhanced in the case of a softer cell. Although the 2D model simplifies real 3D conditions, it provides insight into the effects of geometrical and material parameters relevant to metastasis within capillaries in the presence of both non-activated and activated platelets.

Tumour cell-induced platelet aggregation in breast cancer: Scope of metal nanoparticles

Breast cancer is a major cause of cancer-related mortality among the female population worldwide. Among the various factors promoting breast cancer metastasis, the role of cancer-cell platelet interactions leading to tumour cell-induced platelet aggregation (TCIPA) has garnered significant attention recently. Our state-of-the-art literature review verifies the implications of metal nanoparticles in breast cancer research and TCIPA-specific breast cancer metastasis. We have evaluated in vitro and in vivo research data as well as clinical investigations within the scope of this topic presented in the last ten years. Nanoparticle-based drug delivery platforms in cancer therapy can combat the growing concerns of multi-drug resistance, the alarming rates of chemotherapy-induced toxicities and cancer progression. Metal nanoparticles conjugated with chemotherapeutics can outperform their free drug counterparts in achieving targeted drug delivery and desired drug concentration inside the tumour tissue with minimal toxic effects. Existing data highlights the potential of metal nanoparticles as a promising tool for targeting the platelet-specific interactions associated with breast cancer metastasis including TCIPA.

Platelets and circulating (tumor) cells: partners in promoting metastatic cancer

PURPOSE OF REVIEW

Despite being discovered decades ago, metastasis remains a formidable challenge in cancer treatment. During the intermediate phase of metastasis, tumor cells detach from primary tumor or metastatic sites and travel through the bloodstream and lymphatic system to distant tissues. These tumor cells in the circulation are known as circulating tumor cells (CTCs), and a higher number of CTCs has been linked to poor prognoses in various cancers. The blood is an inhospitable environment for any foreign cells, including CTCs, as they face numerous challenges, such as the shear stress within blood vessels and their interactions with blood and immune cells. However, the exact mechanisms by which CTCs survive the hostile conditions of the bloodstream remain enigmatic. Platelets have been studied for their interactions with tumor cells, promoting their survival, growth, and metastasis. This review explores the latest clinical methods for enumerating CTCs, recent findings on platelet-CTC crosstalk, and current research on antiplatelet therapy as a potential strategy to inhibit metastasis, offering new therapeutic insights.

RECENT FINDINGS

Laboratory and clinical data have provided insights into the role of platelets in promoting CTC survival, while clinical advancements in CTC enumeration offer improved prognostic tools.

SUMMARY

CTCs play a critical role in metastasis, and their interactions with platelets aid their survival in the hostile environment of the bloodstream. Understanding this crosstalk offers insights into potential therapeutic strategies, including antiplatelet therapy, to inhibit metastasis and improve cancer treatment outcomes.

Metastasis and angiogenesis in cervical cancer: key aspects of purinergic signaling in platelets and possible therapeutic targets

Cervical cancer ranks as the fourth most common and fatal cancer among women worldwide. Studies have demonstrated a strong association between purinergic platelet signaling and tumor progression in this type of cancer. The literature shows that neoplastic cells, when in the bloodstream, secrete adenosine triphosphate (ATP) and adenosine nucleotide diphosphate (ADP) that act on their corresponding platelet P2Y and P2X receptors. The interaction of these nucleotides with their receptors results in platelet activation and degranulation, ensuing several consequences, such as vascular endothelial growth factor (VEGF), platelet-derived growth factor, matrix metalloproteinases, ADP, and ATP. These molecules play essential roles in angiogenesis and tumor metastasis in cervical cancer. Several purinergic receptors are found in endothelial cells. Their activation, especially P2Y2, by the nucleotides released by platelets can induce relaxation of the endothelial barrier and consequent extravasation of tumor cells, promoting the development of metastases. Cancer cells that enter the bloodstream during the metastatic process are also subject to high shear stress and immune surveillance. In this context, activated platelets bind to circulating tumor cells and protect them against shear stress and the host's immune system, especially against natural killer cells, facilitating their spread throughout the body. Furthermore, activation of the P2Y12 receptor present on the platelet surface promotes the release of VEGF, the main inducer of angiogenesis in cervical cancer, in addition to increasing the concentration of several other pro-angiogenic molecules. Therefore, this review will address the role of platelet purinergic signaling in tumor progression of cervical cancer and propose possible therapeutic targets.

Towards an emerging role for anticoagulants in cancer therapy: a systematic review and meta-analysis

Background

Anticoagulants, renowned for their role in preventing blood clot formation, have captivated researchers' attention for the exploitation of their potential to inhibit cancer in pre-clinical models.

Objectives

To undertake a systematic review and meta-analysis of the effects of anticoagulants in murine cancer research models. Further, to present a reference tool for anticoagulant therapeutic modalities relating to future animal pre-clinical models of cancer and their translation into the clinic.

Methods

Four databases were utilized including Medline (Ovid), Embase (Ovid), Web of science, and Scopus databases. We included studies relating to any cancer conducted in murine models that assessed the effect of traditional anticoagulants (heparin and its derivatives and warfarin) and newer oral anticoagulants on cancer.

Results

A total of 6,158 articles were identified in an initial multi-database search. A total of 157 records were finally included for data extraction. Studies on heparin species and warfarin demonstrated statistically significant results in favour of tumour growth and metastasis inhibition.

Conclusion

Our findings constitute a valuable reference guide for the application of anticoagulants in cancer research and explore the promising utilization of non-anticoagulants heparin in preclinical cancer research.

Systematic Review Registration

PROSPERO [CRD42024555603].

Sulfated Alginate for Biomedical Applications

Alginate (Alg) polymers have received much attention due to the mild conditions required for gel formation and their good bio-acceptability. However, due to limited interactions with cells, many drugs, and biomolecules, chemically modified alginates are of great interest. Sulfated alginate (S-Alg) is a promising heparin-mimetic that continues to be investigated both as a drug molecule and as a component of biomaterials. Herein, the S-Alg literature of the past five years (2017-2023) is reviewed. Several methods used to synthesize S-Alg are described, with a focus on new advances in characterization and stereoselectivity. Material fabrication is another focus and spans bulk materials, particles, scaffolds, coatings, and part of multicomponent biomaterials. The new application of S-Alg as an antitumor agent is highlighted together with studies evaluating safety and biodistribution. The high binding affinity of S-Alg for various drugs and heparin-binding proteins is exploited extensively in biomaterial design to tune the encapsulation and release of these agents and this aspect is covered in detail. Recommondations include publishing key material properties to allow reproducibility, careful selection of appropriate sulfation strategies, the use of cross-linking strategies other than ionic cross-linking for material fabrication, and more detailed toxicity and biodistribution studies to inform future work.

Treatment with APAC, a dual antiplatelet anticoagulant heparin proteoglycan mimetic, limits early collar-induced carotid atherosclerotic plaque development in Apoe-/- mice

BACKGROUND AND AIMS

Mast cell-derived heparin proteoglycans (HEP-PG) can be mimicked by bioconjugates carrying antithrombotic and anti-inflammatory properties. The dual antiplatelet and anticoagulant (APAC) construct administered, either locally or intravenously (i.v.), targets activated endothelium, its adhesion molecules, and subendothelial matrix proteins, all relevant to atherogenesis. We hypothesized that APAC influences cellular interactions in atherosclerotic lesion development and studied APAC treatment during the initiation and progression of experimental atherosclerosis.

METHODS

Male western-type diet-fed Apoe-/- mice were equipped with perivascular carotid artery collars to induce local atherosclerosis. In this model, mRNA expression of adhesion molecules including ICAM-1, VCAM-1, P-Selectin, and Platelet Factor 4 (PF4) are upregulated upon lesion development. From day 1 (prevention) or from 2.5 weeks after lesion initiation (treatment), mice were administered 0.2 mg/kg APAC i.v. or control vehicle three times weekly for 2.5 weeks. At week 5 after collar placement, mice were sacrificed, and lesion morphology was microscopically assessed.

RESULTS

APAC treatment did not affect body weight or plasma total cholesterol levels during the experiments. In the prevention setting, APAC reduced carotid artery plaque size and volume by over 50 %, aligning with decreased plaque macrophage area and collagen content. During the treatment setting, APAC reduced macrophage accumulation and necrotic core content, and improved markers of plaque stability.

CONCLUSIONS

APAC effectively reduced early atherosclerotic lesion development and improved markers of plaque inflammation in advanced atherosclerosis. Thus, APAC may have potential to alleviate the progression of atherosclerosis.

Unlocking the intricacies: Exploring the complex interplay between platelets and ovarian cancer

Ovarian cancer, an aggressive malignancy of the female reproductive tract, is frequently linked to an elevated risk of thrombotic events. This association is manifested by a pronounced rise in platelet counts and activation levels. Current research firmly supports the pivotal role of platelets in the oncogenic processes of ovarian cancer, influencing tumor cell proliferation and metastasis. Platelets influence these processes through direct interactions with tumor cells or by secreting cytokines and growth factors that enhance tumor growth, angiogenesis, and metastasis. This review aims to thoroughly dissect the interactions between platelets and ovarian cancer cells, emphasizing their combined role in tumor progression and associated thrombotic events. Additionally, it summarizes therapeutic strategies targeting platelet-cancer interface which show significant promise. Such approaches could not only be effective in managing the primary ovarian tumor but also play a pivotal role in preventing metastasis and attenuating thrombotic complications associated with ovarian cancer.

Von Willebrand factor and hematogenous cancer metastasis under flow

Hematogenous metastasis involves cancer cell migration to different locations from the primary tumor through the blood circulation. Von Willebrand factor (VWF) has been shown to play an important role in tumor cell adhesion to and extravasation from the endothelial cell lining of blood vessel walls during cancer metastasis. VWF may contribute to this process by interacting with tumor cells, endothelial cells, and platelets through various cell membrane receptors, such as platelet glycoprotein (GP)Ibα, P-selectin, ανβ3 and αIIbβ3 integrins, and glycocalyx. Blood flow can mechanically extend and activate VWF to bind platelets and associate intermolecularly with other VWF molecules in plasma or on the surface of endothelial cells, cancer cells, or platelets. This suggests a mechanoregulatory role of VWF in mediating the interactions between VWF and these cells to promote cancer cell adhesion to blood vessels. In this review, we will summarize the current knowledge of VWF function and the role of hydrodynamic forces in hematogenous cancer metastasis.

Recent advances in sialic acid-based active targeting chemoimmunotherapy promoting tumor shedding: a systematic review

Tumors have always been a major public health concern worldwide, and attempts to look for effective treatments have never ceased. Sialic acid is known to be a crucial element for tumor development and its receptors are highly expressed on tumor-associated immune cells, which perform significant roles in establishing the immunosuppressive tumor microenvironment and further boosting tumorigenesis, progression, and metastasis. Obviously, it is essential to consider sophisticated crosstalk between tumors, the immune system, and preparations, and understand the links between pharmaceutics and immunology. Sialic acid-based chemoimmunotherapy enables active targeting drug delivery via mediating the recognition between the sialic acid-modified nano-drug delivery system represented by liposomes and sialic acid-binding receptors on tumor-associated immune cells, which inhibit their activity and utilize their homing ability to deliver drugs. Such a "Trojan horse" strategy has remarkably improved the shortcomings of traditional passive targeting treatments, unexpectedly promoted tumor shedding, and persistently induced robust immunological memory, thus highlighting its prospective application potential for targeting various tumors. Herein, we review recent advances in sialic acid-based active targeting chemoimmunotherapy to promote tumor shedding, summarize the current viewpoints on the tumor shedding mechanism, especially the formation of durable immunological memory, and analyze the challenges and opportunities of this attractive approach.

Inhaled heparin: Past, present, and future

While heparin has traditionally served as a key anticoagulant in clinical practice for nearly a century, recent years have witnessed a growing interest in its role as a potent antiinflammatory and antiviral agent, as well as an anticancer agent. To address challenges with injection-based delivery, exploring patient-friendly routes such as oral and pulmonary delivery is crucial. This review specifically highlights the multiple therapeutic benefits of inhaled heparin. In summary, this review serves as a valuable source of information, providing deep insights into the diverse therapeutic advantages of inhaled heparin and its potential applications within clinical contexts.

Engineered Cell Membrane-Coated Nanoparticles: New Strategies in Glioma Targeted Therapy and Immune Modulation

Gliomas, the most prevalent primary brain tumors, pose considerable challenges due to their heterogeneity, intricate tumor microenvironment (TME), and blood-brain barrier (BBB), which restrict the effectiveness of traditional treatments like surgery and chemotherapy. This review provides an overview of engineered cell membrane technologies in glioma therapy, with a specific emphasis on targeted drug delivery and modulation of the immune microenvironment. This study investigates the progress in engineered cell membranes, encompassing physical, chemical, and genetic alterations, to improve drug delivery across the BBB and effectively target gliomas. The examination focuses on the interaction of engineered cell membrane-coated nanoparticles (ECM-NPs) with the TME in gliomas, emphasizing their potential to modulate glioma cell behavior and TME to enhance therapeutic efficacy. The review further explores the involvement of ECM-NPs in immunomodulation techniques, highlighting their impact on immune reactions. While facing obstacles related to membrane stability and manufacturing scalability, the review outlines forthcoming research directions focused on enhancing membrane performance. This review underscores the promise of ECM-NPs in surpassing conventional therapeutic constraints, proposing novel approaches for efficacious glioma treatment.

Endolysosomal transient receptor potential mucolipins and two-pore channels: implications for cancer immunity

Past research has identified that cancer cells sustain several cancer hallmarks by impairing function of the endolysosomal system (ES). Thus, maintaining the functional integrity of endolysosomes is crucial, which heavily relies on two key protein families: soluble hydrolases and endolysosomal membrane proteins. Particularly members of the TPC (two-pore channel) and TRPML (transient receptor potential mucolipins) families have emerged as essential regulators of ES function as a potential target in cancer therapy. Targeting TPCs and TRPMLs has demonstrated significant impact on multiple cancer hallmarks, including proliferation, growth, migration, and angiogenesis both in vitro and in vivo. Notably, endosomes and lysosomes also actively participate in various immune regulatory mechanisms, such as phagocytosis, antigen presentation, and the release of proinflammatory mediators. Yet, knowledge about the role of TPCs and TRPMLs in immunity is scarce. This prompts a discussion regarding the potential role of endolysosomal ion channels in aiding cancers to evade immune surveillance and destruction. Specifically, understanding the interplay between endolysosomal ion channels and cancer immunity becomes crucial. Our review aims to comprehensively explore the current knowledge surrounding the roles of TPCs and TRPMLs in immunity, whilst emphasizing the critical need to elucidate their specific contributions to cancer immunity by pointing out current research gaps that should be addressed.

Immune Cell Migration to Cancer

Immune cell migration is required for the development of an effective and robust immune response. This elegant process is regulated by both cellular and environmental factors, with variables such as immune cell state, anatomical location, and disease state that govern differences in migration patterns. In all cases, a major factor is the expression of cell surface receptors and their cognate ligands. Rapid adaptation to environmental conditions partly depends on intrinsic cellular immune factors that affect a cell's ability to adjust to new environment. In this review, we discuss both myeloid and lymphoid cells and outline key determinants that govern immune cell migration, including molecules required for immune cell adhesion, modes of migration, chemotaxis, and specific chemokine signaling. Furthermore, we summarize tumor-specific elements that contribute to immune cell trafficking to cancer, while also exploring microenvironment factors that can alter these cellular dynamics within the tumor in both a pro and antitumor fashion. Specifically, we highlight the importance of the secretome in these later aspects. This review considers a myriad of factors that impact immune cell trajectory in cancer. We aim to highlight the immunotherapeutic targets that can be harnessed to achieve controlled immune trafficking to and within tumors.

The interaction of platelet-related factors with tumor cells promotes tumor metastasis

Platelets not only participate in thrombosis and hemostasis but also interact with tumor cells and protect them from mechanical damage caused by hemodynamic shear stress and natural killer cell lysis, thereby promoting their colonization and metastasis to distant organs. Platelets can affect the tumor microenvironment via interactions between platelet-related factors and tumor cells. Metastasis is a key event in cancer-related death and is associated with platelet-related factors in lung, breast, and colorectal cancers. Although the factors that promote platelet expression vary slightly in terms of their type and mode of action, they all contribute to the overall process. Recognizing the correlation and mechanisms between these factors is crucial for studying the colonization of distant target organs and developing targeted therapies for these three types of tumors. This paper reviews studies on major platelet-related factors closely associated with metastasis in lung, breast, and colorectal cancers.

Targeting Siglec-Sialylated MUC1 Immune Axis in Cancer

Siglecs play a key role in mediating cell-cell interactions via the recognition of different sialylated glycoconjugates, including tumor-associated MUC1, which can lead to the activation or inhibition of the immune response. The activation occurs through the signaling of Siglecs with the cytoplasmic immunoreceptor tyrosine-based activation motif (ITAM)-containing proteins, while the inhibition signal is a result of the interaction of intracellular immunoreceptor tyrosine-based inhibition motif (ITIM)-bearing receptors. The interaction of tumor-associated MUC1 sialylated glycans with Siglecs via ITIM motifs decreases antitumor immunity. Consequently, these interactions are expected to play a key role in tumor evasion. Efforts to modulate the response of immune cells by blocking the immune-suppressive effects of inhibitory Siglecs, driving immune-activating Siglecs, and/or altering the synthesis and expression of the sialic acid glycocalyx are new therapeutic strategies deserving further investigation. We will highlight the role of Siglec's family receptors in immune evasion through interactions with glycan ligands in their natural context, presented on the protein such as MUC1, factors affecting their fine binding specificities, such as the role of multivalency either at the ligand or receptor side, their spatial organization, and finally the current and future therapeutic interventions targeting the Siglec-sialylated MUC1 immune axis in cancer.

Platelets in Alcohol-Associated Liver Disease: Interaction With Neutrophils

Alcohol-associated liver disease (ALD) is a major contributor to liver-related mortality globally. An increasing body of evidence underscores the pivotal role of platelets throughout the spectrum of liver injury and recovery, offering unique insights into liver homeostasis and pathobiology. Alcoholic-associated steatohepatitis is characterized by the infiltration of hepatic neutrophils. Recent studies have highlighted the extensive distance neutrophils travel through sinusoids to reach the liver injury site, relying on a platelet-paved endothelium for efficient crawling. The adherence of platelets to neutrophils is crucial for accurate migration from circulation to the inflammatory site. A gradual decline in platelet levels leads to diminished neutrophil recruitment. Platelets exhibit the ability to activate neutrophils. Platelet activation is heightened upon the release of platelet granule contents, which synergistically activate neutrophils through their respective receptors. The sequence culminates in the formation of platelet-neutrophil complexes and the release of neutrophil extracellular traps intensifies liver damage, fosters inflammatory immune responses, and triggers hepatotoxic processes. Neutrophil infiltration is a hallmark of alcohol-associated steatohepatitis, and the roles of neutrophils in ALD pathogenesis have been studied extensively, however, the involvement of platelets in ALD has received little attention. The current review consolidates recent findings on the intricate and diverse roles of platelets and neutrophils in liver pathophysiology and in ALD. Potential therapeutic strategies are highlighted, focusing on targeting platelet-neutrophil interactions and activation in ALD. The anticipation is that innovative methods for manipulating platelet and neutrophil functions will open promising avenues for future ALD therapy.

A review on multifaceted biomedical applications of heparin nanocomposites: Progress and prospects

Advances in polymer-based nanocomposites have revolutionized biomedical applications over the last two decades. Heparin (HP), being a highly bioactive polymer of biological origin, provides strong biotic competence to the nanocomposites, broadening the horizon of their applicability. The efficiency, biocompatibility, and biodegradability properties of nanomaterials significantly improve upon the incorporation of heparin. Further, inclusion of structural/chemical derivatives, fractionates, and mimetics of heparin enable fabrication of versatile nanocomposites. Modern nanotechnological interventions have exploited the inherent biofunctionalities of heparin by formulating various nanomaterials, including inorganic/polymeric nanoparticles, nanofibers, quantum dots, micelles, liposomes, and nanogels ensuing novel functionalities targeting diverse clinical applications involving drug delivery, wound healing, tissue engineering, biocompatible coatings, nanosensors and so on. On this note, the present review explicitly summarises the recent HP-oriented nanotechnological developments, with a special emphasis on the reported successful engagement of HP and its derivatives/mimetics in nanocomposites for extensive applications in the laboratory and health-care facility. Further, the advantages and limitations/challenges specifically associated with HP in nanocomposites, undertaken in this current review are quintessential for future innovations/discoveries pertaining to HP-based nanocomposites.

Inhibition of growth of hepatocellular carcinoma by co-delivery of anti-PD-1 antibody and sorafenib using biomimetic nano-platelets

BACKGROUND

Traditional nanodrug delivery systems have some limitations, such as eliciting immune responses and inaccuracy in targeting tumor microenvironments.

MATERIALS AND METHODS

Targeted drugs (Sorafenib, Sora) nanometers (hollow mesoporous silicon, HMSN) were designed, and then coated with platelet membranes to form aPD-1-PLTM-HMSNs@Sora to enhance the precision of drug delivery systems to the tumor microenvironment, so that more effective immunotherapy was achieved.

RESULTS

These biomimetic nanoparticles were validated to have the same abilities as platelet membranes (PLTM), including evading the immune system. The successful coating of HMSNs@Sora with PLTM was corroborated by transmission electron microscopy (TEM), western blot and confocal laser microscopy. The affinity of aPD-1-PLTM-HMSNs@Sora to tumor cells was stronger than that of HMSNs@Sora. After drug-loaded particles were intravenously injected into hepatocellular carcinoma model mice, they were demonstrated to not only directly activate toxic T cells, but also increase the triggering release of Sora. The combination of targeted therapy and immunotherapy was found to be of gratifying antineoplastic function on inhibiting primary tumor growth.

CONCLUSIONS

The aPD-1-PLTM-HMSNs@Sora nanocarriers that co-delivery of aPD-1 and Sorafenib integrates unique biomimetic properties and excellent targeting performance, and provides a neoteric idea for drug delivery of personalized therapy for primary hepatocellular carcinoma (HCC).

A low-anticoagulant heparin suppresses metastatic dissemination through the inhibition of tumor cell-platelets association

Metastasis is the leading cause of cancer-related deaths. Despite this relevance, there is no specific therapy targeting metastasis. The interaction of the tumor cell with platelets, forming microemboli is crucial for successful hematogenous dissemination. Heparin disrupts it by a P-selectin-mediated event. However, its clinical use for this purpose is hindered by the requirement of high doses, leading to anticoagulant-related side effects. In this study, we obtained a low-anticoagulant heparin through the fractionation of a pharmaceutical bovine heparin. This derivative was referred to as LA-hep and we investigated its efficacy in inhibiting metastases and explored its capacity of suppressing the interaction between tumor cells and platelets. Our data revealed that LA-hep is as efficient as porcine unfractionated heparin in attenuating lung metastases from melanoma and colon adenocarcinoma cells in an assay with a single intravenous administration. It also prevents platelet arrest shortly after cell injection in wild-type mice and suppresses melanoma-platelets interaction in vitro. Moreover, LA-hep blocks P-selectin's direct binding to tumor cells and platelet aggregation, providing further evidence for the role of P-selectin as a molecular target. Even in P-selectin-depleted mice which developed a reduced number of metastatic foci, both porcine heparin and LA-hep further inhibited metastasis burden. This suggests evidence of an additional mechanism of antimetastatic action. Therefore, our results indicate a dissociation between the heparin anticoagulant and antimetastatic effects. Considering the simple and highly reproducible methodology used to purify LA-hep along with the data presented here, LA-hep emerges as a promising drug for future use in preventing metastasis in cancer patients.

Blocking tumor-platelet crosstalk to prevent tumor metastasis via reprograming glycolysis using biomimetic membrane-hybridized liposomes

Activated platelets promote tumor progression and metastasis through active interactions with cancer cells, especially in promoting epithelial-mesenchymal transition (EMT) of tumor cells and shedding tumor cells into the blood. Blocking platelet-tumor cell interactions can be a potential strategy to inhibit tumor metastasis. Platelet activation requires energy produced from aerobic glycolysis. Based on this, we propose a platelet suppression strategy by reprogramming glucose metabolism of platelets, which has an advantage over conventional antiplatelet treatment that has a risk of serious hemorrhage. We develop a biomimetic delivery system using platelet membrane-hybridized liposomes (PM-Lipo) for codelivery of quercetin and shikonin to simultaneously inhibit lactate transporter MCT-4 and a glycolytic enzyme PKM2 for achieving metabolic reprogramming of platelets and suppressing platelet activation. Notably, PM-Lipo can also inhibit glycolysis in cancer cells, which actually takes "two-birds-one-stone" action. Consequently, the platelet-tumor cell interactions are inhibited. Moreover, PM-Lipo can bind with circulating tumor cells and reduce their seeding in the premetastatic microenvironment. The in vivo studies further demonstrated that PM-Lipo can effectively suppress primary tumor growth and reduce lung metastasis without affecting inherited functions of platelets. Reprogramming glycolysis of platelets can remodel the tumor immune microenvironment, including suppression of Treg and stimulation of CTLs.

Engineering of surface-modified CuBTC-MXene nanocarrier for adsorption and co-loading of curcumin/paclitaxel from aqueous solutions for synergistic multi-therapy of cancer

Two-dimensional (2D) nanomaterials can improve drug delivery by reducing toxicity, increasing bioavailability and boosting efficacy. In this study, the simultaneous use of transition metal carbides and nitrides (MXenes) along with copper (II) benzene-1, 3, 5-tricarboxylate metal-organic framework (Cu - BTC/MOF) as attractive nanocarriers are investigated for loading and delivering curcumin (CUR) and paclitaxel (PTX) drugs to cancer cells. The efficiency of surface termination (bare and oxygen) in the adsorption of PTX and CUR drugs and the co-loading of these two drugs are evaluated. Our results show that the strongest interaction energy belongs to the adsorption of drug CUR on the MXNNO-Cu-BTC adsorbent, while the interaction of PTX drug with the MXNO- Cu-BTC in the MXNO-Cu-BTC/PTX&CUR system is the lowest due to the particular structure of the drug and the adsorbent. Our results show that at the beginning simulation, the interaction energy between the PTX drug and water in PTX/MXN system is -4645.48 kJ/mol, which reduces to -3848.71 kJ/mol after the system reaches equilibrium. Therefore, the inspected adsorbents have a good performance in adsorbing CUR and PTX drugs. The obtained results from this investigation provide valuable information about experimental studies by medical scientists in the future.Communicated by Ramaswamy H. Sarma.

The dynamic role of platelets in cancer progression and their therapeutic implications

Systemic antiplatelet treatment represents a promising option to improve the therapeutic outcomes and therapeutic efficacy of chemotherapy and immunotherapy due to the critical contribution of platelets to tumour progression. However, until recently, targeting platelets as a cancer therapeutic has been hampered by the elevated risk of haemorrhagic and thrombocytopenic (low platelet count) complications owing to the lack of specificity for tumour-associated platelets. Recent work has advanced our understanding of the molecular mechanisms responsible for the contribution of platelets to tumour progression and metastasis. This has led to the identification of the biological changes in platelets in the presence of tumours, the complex interactions between platelets and tumour cells during tumour progression, and the effects of platelets on antitumour therapeutic response. In this Review, we present a detailed picture of the dynamic roles of platelets in tumour development and progression as well as their use in diagnosis, prognosis and monitoring response to therapy. We also provide our view on how to overcome challenges faced by the development of precise antiplatelet strategies for safe and efficient clinical cancer therapy.

Decoding the role of platelets in tumour metastasis: enigmatic accomplices and intricate targets for anticancer treatments

The canonical role of platelets as central players in cardiovascular disease by way of their fundamental role in mediating thrombosis and haemostasis is well appreciated. However, there is now a large body of experimental evidence demonstrating that platelets are also pivotal in various physiological and pathophysiological processes other than maintaining haemostasis. Foremost amongst these is the emerging data highlighting the key role of platelets in driving cancer growth, metastasis and modulating the tumour microenvironment. As such, there is significant interest in targeting platelets therapeutically for the treatment of cancer. Therefore, the purpose of this review is to provide an overview of how platelets contribute to the cancer landscape and why platelets present as valuable targets for the development of novel cancer diagnosis tools and therapeutics.

Cell membrane biomimetic nanoparticles in drug delivery

Despite the efficiency of nanoparticle (NP) therapy, in vivo investigations have shown that it does not perform as well as in vitro. In this case, NP confronts many defensive hurdles once they enter the body. The delivery of NP to sick tissue is inhibited by these immune-mediated clearance mechanisms. Hence, using a cell membrane to hide NP for active distribution offers up a new path for focused treatment. These NPs are better able to reach the disease's target location, leading to enhanced therapeutic efficacy. In this emerging class of drug delivery vehicles, the inherent relation between the NPs and the biological components obtained from the human body was utilized, which mimic the properties and activities of native cells. This new technology has shown the viability of using biomimicry to evade immune system-provided biological barriers, with an emphasis on restricting clearance from the body before reaching its intended target. Furthermore, by providing signaling cues and transplanted biological components that favorably change the intrinsic immune response at the disease site, the NPs would be capable interacting with immune cells regarding the biomimetic method. Thus, we aimed to provide a current landscape and future trends of biomimetic NPs in drug delivery.

Lipid bilayer-based biological nanoplatforms for sonodynamic cancer therapy

Sonodynamic therapy (SDT) has been developed as a promising alternative therapeutic modality for cancer treatment, involving the synergetic application of sonosensitizers and low-intensity ultrasound. However, the antitumor efficacy of SDT is significantly limited due to the poor performance of conventional sonosensitizers in vivo and the constrained tumor microenvironment (TME). Recent breakthroughs in lipid bilayer-based nanovesicles (LBBNs), including multifunctional liposomes, exosomes, and isolated cellular membranes, have brought new insights into the advancement of SDT. Despite their distinct sources and preparation methods, the lipid bilayer structure in common allows them to be functionalized in many comparable ways to serve as ideal nanocarriers against challenges arising from the tumor-specific sonosensitizer delivery and the complicated TME. In this review, we provide a comprehensive summary of the recent advances in LBBN-based SDT, with particular attention on how LBBNs can be engineered to improve the delivery efficiency of sonosensitizers and overcome physical, biological, and immune barriers within the TME for enhanced sonodynamic cancer therapy. We anticipate that this review will offer valuable guidance in the construction of LBBN-based nanosonosensitizers and contribute to the development of advanced strategies for next-generation sonodynamic cancer therapy.

Organic Electronic Platform for Real-Time Phenotypic Screening of Extracellular-Vesicle-Driven Breast Cancer Metastasis

Tumor-derived extracellular vesicles (TEVs) induce the epithelial-to-mesenchymal transition (EMT) in nonmalignant cells to promote invasion and cancer metastasis, representing a novel therapeutic target in a field severely lacking in efficacious antimetastasis treatments. However, scalable technologies that allow continuous, multiparametric monitoring for identifying metastasis inhibitors are absent. Here, the development of a functional phenotypic screening platform based on organic electrochemical transistors (OECTs) for real-time, noninvasive monitoring of TEV-induced EMT and screening of antimetastatic drugs is reported. TEVs derived from the triple-negative breast cancer cell line MDA-MB-231 induce EMT in nonmalignant breast epithelial cells (MCF10A) over a nine-day period, recapitulating a model of invasive ductal carcinoma metastasis. Immunoblot analysis and immunofluorescence imaging confirm the EMT status of TEV-treated cells, while dual optical and electrical readouts of cell phenotype are obtained using OECTs. Further, heparin, a competitive inhibitor of cell surface receptors, is identified as an effective blocker of TEV-induced EMT. Together, these results demonstrate the utility of the platform for TEV-targeted drug discovery, allowing for facile modeling of the transient drug response using electrical measurements, and provide proof of concept that inhibitors of TEV function have potential as antimetastatic drug candidates.

Can targeted nanoparticles distinguish cancer metastasis from inflammation?

Targeting ligands have been widely used to increase the intratumoral accumulation of nanoparticles and their uptake by cancer cells. However, these ligands aim at targets that are often also upregulated in inflamed tissues. Here, we assessed the ability of targeted nanoparticles to distinguish metastatic cancer from sites of inflammation. Using common targeting ligands and a 60-nm liposome as a representative nanoparticle, we generated three targeted nanoparticle (NP) variants that targeted either fibronectin, folate, or αvβ3 integrin, whose deposition was compared against that of standard untargeted NP. Using fluorescently labeled NPs and ex vivo fluorescence imaging of organs, we assessed the deposition of the NPs into the lungs of mice modeling 4 different biological landscapes, including healthy lungs, aggressive metastasis in lungs, dormant/latent metastasis in lungs, and lungs with general pulmonary inflammation. Among the four NP variants, fibronectin-targeting NP and untargeted NP exhibited the highest deposition in lungs harboring aggressive metastases. However, the deposition of all targeted NP variants in lungs with metastasis was similar to the deposition in lungs with inflammation. Only the untargeted NP was able to exhibit higher deposition in metastasis than inflammation. Moreover, flow-cytometry analysis showed all NP variants accumulated predominantly in immune cells rather than cancer cells. For example, the number of NP+ macrophages and dendritic cells was 16-fold greater than NP+ cancer cells in the case of fibronectin-targeting NP. Overall, targeted NPs were unable to distinguish cancer metastasis from general inflammation, which may have clinical implications to the nanoparticle-mediated delivery of cancer drugs.

Non-Anticoagulant Activities of Low Molecular Weight Heparins-A Review

Low molecular weight heparins (LMWHs) are derived from heparin through chemical or enzymatic cleavage with an average molecular weight (Mw) of 2000-8000 Da. They exhibit more selective activities and advantages over heparin, causing fewer side effects, such as bleeding and heparin-induced thrombocytopenia. Due to different preparation methods, LMWHs have diverse structures and extensive biological activities. In this review, we describe the basic preparation methods in this field and compare the main principles and advantages of these specific methods in detail. Importantly, we focus on the non-anticoagulant pharmacological effects of LMWHs and their conjugates, such as preventing glycocalyx shedding, anti-inflammatory, antiviral infection, anti-fibrosis, inhibiting angiogenesis, inhibiting cell adhesion and improving endothelial function. LMWHs are effective in various diseases at the animal level, including cancer, some viral diseases, fibrotic diseases, and obstetric diseases. Finally, we briefly summarize their usage and potential applications in the clinic to promote the development and utilization of LMWHs.

A Biomimicking and Multiarm Self-Indicating Nanoassembly for Site-Specific Photothermal-Potentiated Thrombolysis Assessed in Microfluidic and In Vivo Models

Thrombolytic and antithrombotic therapies are limited by short circulation time and the risk of off-target hemorrhage. Integrating a thrombus-homing strategy with photothermal therapy are proposed to address these limitations. Using glycol chitosan, polypyrrole, iron oxide and heparin, biomimicking GCPIH nanoparticles are developed for targeted thrombus delivery and thrombolysis. The nanoassembly achieves precise delivery of polypyrrole, exhibiting biocompatibility, selective accumulation at multiple thrombus sites, and enhanced thrombolysis through photothermal activation. To simulate targeted thrombolysis, a microfluidic model predicting thrombolysis dynamics in realistic pathological scenarios is designed. Human blood assessments validate the precise homing of GCPIH nanoparticles to activated thrombus microenvironments. Efficient near-infrared phototherapeutic effects are demonstrated at thrombus lesions under physiological flow conditions ex vivo. The combined investigations provide compelling evidence supporting the potential of GCPIH nanoparticles for effective thrombus therapy. The microfluidic model also offers a platform for advanced thrombolytic nanomedicine development.

Cyclooxygenases and platelet functions

Cyclooxygenase (COX) isozymes, i.e., COX-1 and COX-2, are encoded by separate genes and are involved in the generation of the same products, prostaglandin (PG)G₂ and PGH₂ from arachidonic acid (AA) by the COX and peroxidase activities of the enzymes, respectively. PGH₂ is then transformed into prostanoids in a tissue-dependent fashion due to the different expression of downstream synthases. Platelets present almost exclusively COX-1, which generates large amounts of thromboxane (TX)A₂, a proaggregatory and vasoconstrictor mediator. This prostanoid plays a central role in atherothrombosis, as shown by the benefit of the antiplatelet agent low-dose aspirin, a preferential inhibitor of platelet COX-1. Recent findings have shown the relevant role played by platelets and TXA₂ in developing chronic inflammation associated with several diseases, including tissue fibrosis and cancer. COX-2 is induced in response to inflammatory and mitogenic stimuli to generate PGE₂ and PGI₂ (prostacyclin), in inflammatory cells. However, PGI₂ is constitutively expressed in vascular cells in vivo and plays a crucial role in protecting the cardiovascular systems due to its antiplatelet and vasodilator effects. Here, platelets' role in regulating COX-2 expression in cells of the inflammatory microenvironment is described. Thus, the selective inhibition of platelet COX-1-dependent TXA₂ by low-dose aspirin prevents COX-2 induction in stromal cells leading to antifibrotic and antitumor effects. The biosynthesis and functions of other prostanoids, such as PGD₂, and isoprostanes, are reported. In addition to aspirin, which inhibits platelet COX-1 activity, possible strategies to affect platelet functions by influencing platelet prostanoid receptors or synthases are discussed.

Glycol-Split Heparin-Linked Prodrug Nanoparticles Target the Mitochondrion Apparatus for Cancer Metastasis Treatment

The progression and metastasis of solid tumors rely strongly on neovascularization. However, angiogenesis inhibitors alone cannot meet the needs of tumor therapy. This study prepared a new drug conjugate (PTX-GSHP-CYS-ES2, PGCE) by combining polysaccharides (heparin without anticoagulant activity, GSHP), chemotherapeutic drugs (paclitaxel, PTX), and antiangiogenic drugs (ES2). Furthermore, a tumor-targeted prodrug nanoparticle delivery system is established. The nanoparticles appear to accumulate in the mitochondrial of tumor cells and achieve ES2 and PTX release under high glutathione and acidic environment. It has been confirmed that PGCE inhibited the expression of multiple metastasis-related proteins by targeting the tumor cell mitochondrial apparatus and disrupting their structure. Furthermore, PGCE nanoparticles inhibit migration, invasion, and angiogenesis in B16F10 tumor-bearing mice and suppress tumor growth and metastasis in vitro. Further in vitro and in vivo experiments show that PGCE has strong antitumor growth and metastatic effects and exhibits efficient anti-angiogenesis properties. This multi-targeted nanoparticle system potentially enhances the antitumor and anti-metastatic effects of combination chemotherapy and antiangiogenic drugs.

Preoperative administration of a biomimetic platelet nanodrug enhances postoperative drug delivery by bypassing thrombus

The postoperative thrombus attached to the damaged blood vessels severely obstructs drugs from crossing the damaged blood-brain barrier (BBB) and targeting residual glioma cells around surgical margins, leading to glioblastoma (GBM) recurrence. A thrombus-bypassing, BBB-crossing, and surgical margin-targeted nanodrug is needed to address this phenomenon. Encouraged by the intrinsic damaged vascular endothelium chemotaxis of platelets, a platelet membrane-coated nanodrug (PM-HDOX) delivering doxorubicin (DOX) for postoperative GBM treatment is proposed and systematically investigated. Because surgery damages the vascular endothelium on the BBB around the surgical margin, the platelet membrane coating endows PM-HDOX with its inherent capacity to cross the broken BBB and target the surgical margin. Moreover, preoperative administration combined with fast-targeted PM-HDOX can realize the potential of bypassing thrombus. In GBM resection models, PM-HDOX with preoperative administration demonstrated significantly enhanced BBB-crossing and surgical margin-targeted efficacy. In particular, the PM-HDOX intensities around the surgical margins of the preoperative administration group were more than twice that of the postoperative administration group due to bypassing the thrombus formed in the broken BBB. In the antitumor experiment, the preoperative administration of PM-HDOX significantly inhibited the growth of postoperative residual tumors and prolonged the median survival time of mice. In conclusion, preoperative administration of a biomimetic platelet nanodrug can be an efficient and promising drug delivery strategy for residual GBM after surgery.

Prostate cancer cell-platelet bidirectional signaling promotes calcium mobilization, invasion and apoptotic resistance via distinct receptor-ligand pairs

Platelets play a crucial role in cancer and thrombosis. However, the receptor-ligand repertoire mediating prostate cancer (PCa) cell-platelet interactions and ensuing consequences have not been fully elucidated. Microvilli emanating from the plasma membrane of PCa cell lines (RC77 T/E, MDA PCa 2b) directly contacted individual platelets and platelet aggregates. PCa cell-platelet interactions were associated with calcium mobilization in platelets, and translocation of P-selectin and integrin α_IIbβ₃ onto the platelet surface. PCa cell-platelet interactions reciprocally promoted PCa cell invasion and apoptotic resistance, and these events were insensitive to androgen receptor blockade by bicalutamide. PCa cells were exceedingly sensitive to activation by platelets in vitro, occurring at a PCa cell:platelet coculture ratio as low as 1:10 (whereas PCa patient blood contains 1:2,000,000 per ml). Conditioned medium from cocultures stimulated PCa cell invasion but not apoptotic resistance nor platelet aggregation. Candidate transmembrane signaling proteins responsible for PCa cell-platelet oncogenic events were identified by RNA-Seq and broadly divided into 4 major categories: (1) integrin-ligand, (2) EPH receptor-ephrin, (3) immune checkpoint receptor-ligand, and (4) miscellaneous receptor-ligand interactions. Based on antibody neutralization and small molecule inhibitor assays, PCa cell-stimulated calcium mobilization in platelets was found to be mediated by a fibronectin1 (FN1)-α_IIbβ₃ signaling axis. Platelet-stimulated PCa cell invasion was facilitated by a CD55-adhesion G protein coupled receptor E5 (ADGRE5) axis, with contribution from platelet cytokines CCL3L1 and IL32. Platelet-stimulated PCa cell apoptotic resistance relied on ephrin-EPH receptor and lysophosphatidic acid (LPA)-LPA receptor (LPAR) signaling. Of participating signaling partners, FN1 and LPAR3 overexpression was observed in PCa specimens compared to normal prostate, while high expression of CCR1 (CCL3L1 receptor), EPHA1 and LPAR5 in PCa was associated with poor patient survival. These findings emphasize that non-overlapping receptor-ligand pairs participate in oncogenesis and thrombosis, highlighting the complexity of any contemplated clinical intervention strategy.

Interactions between Platelets and Tumor Microenvironment Components in Ovarian Cancer and Their Implications for Treatment and Clinical Outcomes

Platelets, the primary operatives of hemostasis that contribute to blood coagulation and wound healing after blood vessel injury, are also involved in pathological conditions, including cancer. Malignancy-associated thrombosis is common in ovarian cancer patients and is associated with poor clinical outcomes. Platelets extravasate into the tumor microenvironment in ovarian cancer and interact with cancer cells and non-cancerous elements. Ovarian cancer cells also activate platelets. The communication between activated platelets, cancer cells, and the tumor microenvironment is via various platelet membrane proteins or mediators released through degranulation or the secretion of microvesicles from platelets. These interactions trigger signaling cascades in tumors that promote ovarian cancer progression, metastasis, and neoangiogenesis. This review discusses how interactions between platelets, cancer cells, cancer stem cells, stromal cells, and the extracellular matrix in the tumor microenvironment influence ovarian cancer progression. It also presents novel potential therapeutic approaches toward this gynecological cancer.

Platelet-derived TLT-1 promotes tumor progression by suppressing CD8+ T cells

Current understanding of tumor immunosuppressive mechanisms forms the basis for modern day immunotherapies. Immunoregulatory role of platelets in cancer remains largely elusive. Platelets from non-small cell lung cancer (NSCLC) patients revealed a distinct activation phenotype. TREM-like transcript 1 (TLT-1), a platelet protein, was increased along with enhanced extracellular release from NSCLC platelets. The increased platelet TLT-1 was also evident in humanized mice with patient-derived tumors. In immunocompetent mice with syngeneic tumors, TLT-1 binding to T cells, in vivo, led to suppression of CD8 T cells, promoting tumor growth. We identified direct interaction between TLT-1 and CD3ε on T cells, implicating the NF-κB pathway in CD8 T cell suppression. Anti-TLT-1 antibody rescued patients' T cells from platelet-induced suppression ex vivo and reduced tumors in mice in vivo. Clinically, higher TLT-1 correlated with reduced survival of NSCLC patients. Our findings thus identify TLT-1 as a platelet-derived immunosuppressor that suppresses CD8 T cells and demonstrate its therapeutic and prognostic significance in cancer.

Advances in nanomaterial-based targeted drug delivery systems

Nanomaterial-based drug delivery systems (NBDDS) are widely used to improve the safety and therapeutic efficacy of encapsulated drugs due to their unique physicochemical and biological properties. By combining therapeutic drugs with nanoparticles using rational targeting pathways, nano-targeted delivery systems were created to overcome the main drawbacks of conventional drug treatment, including insufficient stability and solubility, lack of transmembrane transport, short circulation time, and undesirable toxic effects. Herein, we reviewed the recent developments in different targeting design strategies and therapeutic approaches employing various nanomaterial-based systems. We also discussed the challenges and perspectives of smart systems in precisely targeting different intravascular and extravascular diseases.

Research Progress of Nanomedicine-Based Mild Photothermal Therapy in Tumor

With the booming development of nanomedicine, mild photothermal therapy (mPTT, 42-45°C) has exhibited promising potential in tumor therapy. Compared with traditional PTT (>50°C), mPTT has less side effects and better biological effects conducive to tumor treatment, such as loosening the dense structure in tumor tissues, enhancing blood perfusion, and improving the immunosuppressive microenvironment. However, such a relatively low temperature cannot allow mPTT to completely eradicate tumors, and therefore, substantial efforts have been conducted to optimize the application of mPTT in tumor therapy. This review extensively summarizes the latest advances of mPTT, including two sections: (1) taking mPTT as a leading role to maximize its effect by blocking the cell defense mechanisms, and (2) regarding mPTT as a supporting role to assist other therapies to achieve synergistic antitumor curative effect. Meanwhile, the special characteristics and imaging capabilities of nanoplatforms applied in various therapies are discussed. At last, this paper puts forward the bottlenecks and challenges in the current research path of mPTT, and possible solutions and research directions in future are proposed correspondingly.

Theranostic Applications of Glycosaminoglycans in Metastatic Renal Cell Carcinoma

Renal cell carcinoma (RCC) makes up the majority of kidney cancers, with a poor prognosis for metastatic RCC (mRCC). Challenges faced in the management of mRCC, include a lack of reliable prognostic markers and biomarkers for precise monitoring of disease treatment, together with the potential risk of toxicity associated with more recent therapeutic options. Glycosaminoglycans (GAGs) are a class of carbohydrates that can be categorized into four main subclasses, viz., chondroitin sulfate, hyaluronic acid, heparan sulfate and keratan sulfate. GAGs are known to be closely associated with cancer progression and modulation of metastasis by modification of the tumor microenvironment. Alterations of expression, composition and spatiotemporal distribution of GAGs in the extracellular matrix (ECM), dysregulate ECM functions and drive cancer invasion. In this review, we focus on the clinical utility of GAGs as biomarkers for mRCC (which is important for risk stratification and strategizing effective treatment protocols), as well as potential therapeutic targets that could benefit patients afflicted with advanced RCC. Besides GAG-targeted therapies that holds promise in mRCC, other potential strategies include utilizing GAGs as drug carriers and their mimetics to counter cancer progression, and enhance immunotherapy through binding and transducing signals for immune mediators.

Micellar nanoparticles inhibit breast cancer and pulmonary metastasis by modulating the recruitment and depletion of myeloid-derived suppressor cells

Myeloid-derived suppressor cells (MDSCs) are notorious for their pathological characteristics of immunosuppression and their promoting effect on cancers. They can induce the formation of pre-metastatic niche (PMN) characterized by inflammation, immunosuppression and vascular leakage, and promote pulmonary metastasis of breast cancer. Herein, a tumor targeting c(RGDfk) peptide modified low molecular-weight-heparin-all-trans-retinoic-acid (LMWH-ATRA) micellar nanoparticle loaded with chemotherapeutic drug doxorubicin (DOX) and immune adjuvant α-galactosylceramide (αGC) (RLA/DOX/αGC NP) was developed. The hydrophilic segment LMWH inhibited the recruitment of MDSCs by competitively binding with P-selectin on the surface of vascular endothelial cells (VECs), while the hydrophobic segment ATRA promoted the depletion of MDSCs by inducing their differentiation. Through the modulation of MDSCs, micelles can significantly improve the inflammatory and immunosuppressive microenvironment of the lung and tumor sites, and inhibit the formation of PMN. Not only this, the micelles also produced a synergistic effect with αGC, which effectively improved the anti-tumor immunity of tumor bearing mice and provided a promising therapeutic strategy for breast cancer and pulmonary metastasis.

Programmed prodrug breaking the feedback regulation of P-selectin in plaque inflammation for atherosclerotic therapy

Inflammation is the main driver of the aggravation of arteriosclerosis, and the complex inflammatory response in plaque is usually the result of the interaction of various cells and cytokines. Therefore, it is difficult to comprehensively regulate the inflammatory process of arteriosclerosis by intervening a single target, resulting in the poor effect of existing treatment method. Based on our clinical findings that P-selectin stably and highly expressed in patients' plaque endothelial cells, the programmed prodrug, low molecular weight heparin-indomethacin nanoparticles (LI NPs), were established as anti-inflammatory agent to multiphase inhibit arteriosclerosis by cascade interference of P-selectin. Structurally, LI NPs was obtained by simple esterification of low molecular weight heparin and indomethacin without any additives, guaranteeing the biocompatibility and applicability of LI NPs. Functionally, LI NPs could interfere with P-selectin in the inflammatory process, such as inhibiting macrophage adhesion, reducing the secretion of inflammatory factors, and inducing macrophage apoptosis. In the arteriosclerosis mice model, LI NPs significantly reduced the plaque area and showed satisfactory curative effect, which is related to the intervention of the multiphase inflammation between endothelial cells and macrophages. In conclusion, the programmed prodrug LI NPs offered a promising approach for the clinical therapy of arteriosclerosis.

Polyglycerols as Multi-Functional Platforms: Synthesis and Biomedical Applications

The remarkable and unique characteristics of polyglycerols (PG) have made them an attractive candidate for many applications in the biomedical and pharmaceutical fields. The presence of multiple hydroxy groups on the flexible polyether backbone not only enables the further modification of the PG structure but also makes the polymer highly water-soluble and results in excellent biocompatibility. In this review, the polymerization routes leading to PG with different architectures are discussed. Moreover, we discuss the role of these polymers in different biomedical applications such as drug delivery systems, protein conjugation, and surface modification.

Tumor Cell-Induced Platelet Aggregation as an Emerging Therapeutic Target for Cancer Therapy

Tumor cells have the ability to induce platelet activation and aggregation. This has been documented to be involved in tumor progression in several types of cancers, such as lung, colon, breast, pancreatic, ovarian, and brain. During the process, platelets protect circulating tumor cells from the deleterious effects of shear forces, shield tumor cells from the immune system, and provide growth factors, facilitating metastatic spread and tumor growth at the original site as well as at the site of metastasis. Herein, we present a wider view on the induction of platelet aggregation by specific factors primarily developed by cancer, including coagulation factors, adhesion receptors, growth factors, cysteine proteases, matrix metalloproteinases, glycoproteins, soluble mediators, and selectins. These factors may be presented on the surface of tumor cells as well as in their microenvironment, and some may trigger more than just one simple receptor-ligand mechanism. For a better understanding, we briefly discuss the physiological role of the factors in the platelet activation process, and subsequently, we provide scientific evidence and discuss their potential role in the progression of specific cancers. Targeting tumor cell-induced platelet aggregation (TCIPA) by antiplatelet drugs may open ways to develop new treatment modalities. On the one hand, it may affect patients' prognosis by enhancing known therapies in advanced-stage tumors. On the other hand, the use of drugs that are mostly easily accessible and widely used in general practice may be an opportunity to propose an unparalleled antitumor prophylaxis. In this review, we present the recent discoveries of mechanisms by which cancer cells activate platelets, and discuss new platelet-targeted therapeutic strategies.

The overall process of metastasis: From initiation to a new tumor

Metastasis-a process that involves the migration of cells from the primary site to distant organs-is the leading cause of cancer-associated death. Improved technology and in-depth research on tumors have furthered our understanding of the various mechanisms involved in tumor metastasis. Metastasis is initiated by cancer cells of a specific phenotype, which migrate with the assistance of extracellular components and metastatic traits conferred via epigenetic regulation while modifying their behavior in response to the complex and dynamic human internal environment. In this review, we have summarized the general steps involved in tumor metastasis and their characteristics, incorporating recent studies and topical issues, including epithelial-mesenchymal transition, cancer stem cells, neutrophil extracellular traps, pre-metastatic niche, extracellular vesicles, and dormancy. Several feasible treatment directions have also been summarized. In addition, the correlation between cancer metastasis and lifestyle factors, such as obesity and circadian rhythm, has been illustrated.

The Auxiliary Role of Heparin in Bone Regeneration and its Application in Bone Substitute Materials

Bone regeneration in large segmental defects depends on the action of osteoblasts and the ingrowth of new blood vessels. Therefore, it is important to promote the release of osteogenic/angiogenic growth factors. Since the discovery of heparin, its anticoagulant, anti-inflammatory, and anticancer functions have been extensively studied for over a century. Although the application of heparin is widely used in the orthopedic field, its auxiliary effect on bone regeneration is yet to be unveiled. Specifically, approximately one-third of the transforming growth factor (TGF) superfamily is bound to heparin and heparan sulfate, among which TGF-β1, TGF-β2, and bone morphogenetic protein (BMP) are the most common growth factors used. In addition, heparin can also improve the delivery and retention of BMP-2 in vivo promoting the healing of large bone defects at hyper physiological doses. In blood vessel formation, heparin still plays an integral part of fracture healing by cooperating with the platelet-derived growth factor (PDGF). Importantly, since heparin binds to growth factors and release components in nanomaterials, it can significantly facilitate the controlled release and retention of growth factors [such as fibroblast growth factor (FGF), BMP, and PDGF] in vivo. Consequently, the knowledge of scaffolds or delivery systems composed of heparin and different biomaterials (including organic, inorganic, metal, and natural polymers) is vital for material-guided bone regeneration research. This study systematically reviews the structural properties and auxiliary functions of heparin, with an emphasis on bone regeneration and its application in biomaterials under physiological conditions.

Advancements in cell membrane camouflaged nanoparticles: A bioinspired platform for cancer therapy

The idea of employing natural cell membranes as a coating medium for nanoparticles (NPs) endows man-made vectors with natural capabilities and benefits. In addition to retaining the physicochemical characteristics of the NPs, the biomimetic NPs also have the functionality of source cell membranes. It has emerged as a promising approach to enhancing the properties of NPs for drug delivery, immune evasion, imaging, cancer-targeting, and phototherapy sensitivity. Several studies have been reported with a multitude of approaches to reengineering the surface of NPs using biological membranes. Owing to their low immunogenicity and intriguing biomimetic properties, cell-membrane-based biohybrid delivery systems have recently gained a lot of interest as therapeutic delivery systems. This review summarises different kinds of biomimetic NPs reported so far, their fabrication aspects, and their application in the biomedical field. Finally, it briefs on the latest advances available in this biohybrid concept.

Bioengineered Platelets Combining Chemotherapy and Immunotherapy for Postsurgical Melanoma Treatment: Internal Core-Loaded Doxorubicin and External Surface-Anchored Anti-PD-L1 Antibody Backpacks

The pivotal factors affecting the survival rate of patients include metastasis and tumor recurrence after the resection of the primary tumor. Anti-PD-L1 antibody (aPD-L1) has promising efficacy but with some side effects for the off-target binding between aPD-L1 and normal tissues. Here, inspired by the excellent targeting capability of platelets with respect to tumor cells, we propose bioengineered platelets (PDNGs) with inner-loaded doxorubicin (DOX) and outer-anchored aPD-L1-cross-linked nanogels to reduce tumor relapse and metastatic spread postoperation. The cargo does not impair the normal physiological functions of platelets. Free aPD-L1 is cross-linked to form nanogels with a higher drug-loading efficiency and is sustainably released to trigger the T-cell-mediated destruction of tumor cells, reversing the tumor immunosuppressive microenvironment. PDNGs can reduce the postoperative tumor recurrence and metastasis rate, prolonging the survival time of mice. Our findings indicate that bioengineered platelets are promising in postsurgical cancer treatment by the tumor-capturing and in situ microvesicle-secreting capabilities of platelets.

Glycosoaminoglycans in cancer therapy

Glycosaminoglycans (GAGs) are an important component of the tumor microenvironment (TME). GAGs can interact with a variety of binding partners and thereby influence cancer progression on multiple levels. GAGs can modulate growth factor and chemokine signaling, invasion and metastasis formation. Moreover, GAGs are able to change the physical property of the extracellular matrix (ECM). Abnormalities in GAG abundance and structure (e.g., sulfation patterns and molecular weight) are found across various cancer types and show biomarker potential. Targeting GAGs, as well as the usage of GAGs and their mimetics, are promising approaches to interfere with cancer progression. In addition, GAGs can be used as drug and cytokine carriers to induce an anti-tumor response. In this review, we summarize the role of GAGs in cancer and the potential use of GAGs and GAG derivatives to target cancer.