Involvement of platelet-tumor cell interaction in immune evasion. Potential role of podocalyxin-like protein 1

Worth of pan-immune-inflammation value in trismus prediction after concurrent chemoradiotherapy for nasopharyngeal carcinomas

OBJECTIVE

Radiation-induced trismus (RIT), one of the rare but serious side effects of concurrent chemoradiotherapy (C-CRT), is difficult to predict with high accuracy. We aimed to examine whether the pretreatment pan-immune-inflammation value (PIV) measures predict RIT in patients with locally advanced nasopharyngeal carcinoma (LA-NPC) receiving C-CRT.

METHODS

Data of patients with LA-NPC who underwent C-CRT and had maximum mouth openings (MMO) > 35 mm were reviewed. Any MMO of 35 mm or less after C-CRT was considered RIT. All PIV values were computed using the complete blood count test results: PIV = (Platelets × Monocytes × Neutrophils) ÷ Lymphocytes. The receiver operating characteristic analysis was employed to dissect a possible association between pre-treatment PIV readings and RIT status. Confounding variables were tested for their independent relationship with the RIT rates using logistic regression analysis.

RESULTS

The research comprised 223 participants, and RIT was diagnosed in 46 (20.6%) at a median time from C-CRT to RIT of 10 months (range: 5-18 months). Pre-C-CRT PIV levels and RIT rates were analyzed using receiver operating characteristic curve analysis, with 830 being the optimal cutoff (area under the curve: 92.1%; sensitivity: 87.5%; specificity: 85.5%; Youden index: 0.730). RIT was significantly more prevalent in the PIV > 830 cohort than its PIV ≤ 830 counterpart (60.3% vs. 5%; hazard ratio 5.79; P < 0.001). Multivariate logistic regression analysis revealed that advanced T-stage (P = 0.004), masticatory apparatus dose V58Gy≥%32 (P = 0.003), and PIV > 830 (P < 0.001) were independently linked with significantly elevated rates of RIT.

CONCLUSION

The presence of elevated pre-C-CRT PIV is a unique biological marker that independently predicts increased RIT rates in LA-NPC undergoing C-CRT.

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.

Blood-Based Biomarker Analysis for Predicting Efficacy of Chemoradiotherapy and Durvalumab in Patients with Unresectable Stage III Non-Small Cell Lung Cancer

We recruited 50 patients with unresectable stage III NSCLC who received CCRT between March 2020 and March 2021. Durvalumab consolidation (DC) was administered to patients (n = 23) without progression after CCRT and programmed death-ligand 1 (PD-L1) ≥ 1%. Blood samples were collected before (C0) and after CCRT (C1) to calculate PBC counts and analyze CTCs. CTCs, isolated by the CD-PRIME^TM system, exhibited EpCAM/CK+/CD45- phenotype in BioViewCCBS^TM. At median follow-up of 27.4 months, patients with residual CTC clusters at C1 had worse median PFS than those without a detectable CTC cluster (11.0 vs. 27.8 months, p = 0.032), and this trend was noted only in the DC group (p = 0.034). Patients with high platelets at C1 (PLT^hi, >252 × 10³/µL) had worse median PFS than those with low platelets (PLT^lo) (5.9 vs. 17.1 months, p < 0.001). In multivariable analysis, PLT^hi and residual CTC clusters at C1 were independent risk factors for PFS, and DC group with PLT^hi and residual CTC clusters at C1 showed the worst median PFS (2.6 months, HR 45.16, p = 0.001), even worse than that of the CCRT alone group with PLT^hi (5.9 months, HR 15.39, p = 0.001). The comprehensive analysis of CTCs and PBCs before and after CCRT revealed that the clearance of CTC clusters and platelet counts at C1 might be potential biomarkers for predicting survival.

Contents in tumor-educated platelets as the novel biosource for cancer diagnostics

Liquid biopsy, a powerful non-invasive test, has been widely used in cancer diagnosis and treatment. Platelets, the second most abundant cells in peripheral blood, are becoming one of the richest sources of liquid biopsy with the capacity to systematically and locally respond to the presence of cancer and absorb and store circulating proteins and different types of nucleic acids, thus called "tumor-educated platelets (TEPs)". The contents of TEPs are significantly and specifically altered, empowering them with the potential as cancer biomarkers. The current review focuses on the alternation of TEP content, including coding and non-coding RNA and proteins, and their role in cancer diagnostics.

Surgical Stress and Cancer Progression: New Findings and Future Perspectives

PURPOSE OF REVIEW

The stress response to surgery is essential for maintaining homeostasis and exhibits anti-tumor effects; however, an ongoing and exaggerated stress response may have adverse clinical consequences and even promote cancer progression. This review will discuss the complex relationship between surgical stress and cancer progression.

RECENT FINDINGS

Surgical stress exhibits both anti-tumor and cancer-promoting effects by causing changes in the neuroendocrine, circulatory, and immune systems. Many studies have found that many mechanisms are involved in the process, and the corresponding targets could be applied for cancer therapy. Although surgical stress may have anti-tumor effects, it is necessary to inhibit an excessive stress response, mostly showing cancer-promoting effects.

A novel immunochemotherapy based on immunogenicity-activated and immunosuppression-reversed biomimetic nanoparticles

Studies show that infiltrated myeloid-derived suppressor cells (MDSCs) are vital in the immunosuppressive tumor microenvironment and account for lymphoma refractoriness and recurrence. Here, we developed a biomimetic nanoplatform (PM-PLGA-DOX/GEM) in which platelet membranes (PM) wrap PLGA nanoparticles co-loaded with doxorubicin (DOX) and gemcitabine (GEM). PM-PLGA-DOX/GEM would accumulate in tumor tissues because of the enhanced permeation and retention (EPR) effect and the tumor cell-induced platelet aggregation (TCIPA) effect. GEM could eliminate the MDSCs in tumor tissues, thereby reversing the immunosuppressive tumor microenvironment. Furthermore, DOX could invoke the immunogenic cell death (ICD) of lymphoma cells. Consequently, numerous T cells were recruited and activated to improve the therapeutic effects. This study will offer a potential platform for clinical treatment of lymphoma and other solid tumors.

Anesthesia and cancer recurrence: an overview

Several perioperative factors are responsible for the dysregulation or suppression of the immune system with a possible impact on cancer cell growth and the development of new metastasis. These factors have the potential to directly suppress the immune system and activate hypothalamic-pituitary-adrenal axis and the sympathetic nervous system with a consequent further immunosuppressive effect.Anesthetics and analgesics used during the perioperative period may modulate the innate and adaptive immune system, inflammatory system, and angiogenesis, with a possible impact on cancer recurrence and long-term outcome. Even if the current data are controversial and contrasting, it is crucial to increase awareness about this topic among healthcare professionals for a future better and conscious choice of anesthetic techniques.In this article, we aimed to provide an overview regarding the relationship between anesthesia and cancer recurrence. We reviewed the effects of surgery, perioperative factors, and anesthetic agents on tumor cell survival and tumor recurrence.

Investigation of Biomarkers Associated with Low Platelet Counts in Normal Karyotype Acute Myeloid Leukemia

Acute myeloid leukemia (AML) patients are at risk of bleeding due to disease-related lack of platelets and systemic coagulopathy. Platelets play a role in hemostasis. Leukemic blasts have been shown to alter platelet activation in vitro. Here we investigated biomarkers associated with thrombocytopenia in normal karyotype AML (NK-AML). From The Cancer Genome Atlas database, case-control study was performed between normal karyotype (NK) platelet-decreased AML (PD-AML, platelet count < 100 × 109/L, n = 24) and NK platelet-not-decreased AML (PND-AML, with platelet count ≥ 100 × 109/L, n = 13). Differentially expressed gene analysis, pathway analysis and modelling for predicting platelet decrease in AML were performed. DEG analysis and pathway analysis revealed 157 genes and eight pathways specific for PD-AML, respectively. Most of the eight pathways were significantly involved in G-protein-coupled receptor-related pathway, cytokine-related pathway, and bone remodeling pathway. Among the key genes involved in at least one pathway, three genes including CSF1R, TNFSF15 and CLEC10A were selected as promising biomarkers for predicting PD-AML (0.847 of AUC in support vector machine model). This is the first study that identified biomarkers using RNA expression data analysis and could help understand the pathophysiology in AML with low platelet count.

Impact of Platelets to Lymphocytes Ratio and Lymphocytes during Radical Concurrent Radiotherapy and Chemotherapy on Patients with Nonmetastatic Esophageal Squamous Cell Carcinoma

Purpose

This study examined the importance of hematological parameters as prognostic markers for people with esophageal cancer receiving radical concurrent chemoradiation.

Methods

106 patients with esophageal cancer are included in this study. Cox regression analysis, Kaplan-Meier method, and chi-square test were used to analyze our data.

Results

The median follow-up time for patients was 15.5 months (3-55). Univariate and multivariate analyses showed that age, the change of platelet-to-lymphocyte ratio (ΔPLR), and the change rate of circulating lymphocyte count (ΔCLC%) were independent influencing factors of OS and DFS. The patients were grouped according to the median of ΔPLR and ΔCLC%, and analysis showed that a higher ΔPLR and a higher ΔCLC% was related to poor OS and DFS (P < 0.001, P < 0.001 and P < 0.001, P < 0.001). By subgroup analysis, the OS of T1-4N1-2 were better in the low ΔPLR group than the high one (P = 0.03, P < 0.001, P = 0.001, P < 0.001, and P = 0.008). DFS of T3-4N1-2 in the low ΔPLR group were better than the high one (P < 0.001, P = 0.016 and P < 0.001, P = 0.022). For patients with T1-4N0-2, the OS in the low ΔCLC% group were better than in the high ΔCLC% group (P = 0.01, P < 0.001, P < 0.002, P = 0.012, P < 0.001, and P = 0.024). For T1-4N1-2, the DFS were better in the low ΔCLC% group than others (P = 0.042, P < 0.001, P < 0.001, P < 0.001, and P = 0.006).

Conclusion

ΔPLR and ΔCLC% are independent factors of OS and DFS, and a lower ΔPLR and ΔCLC% are associated with a better OS and DFS. And T3-4N1-2 patients in the low ΔPLR group and low ΔCLC% group have greater survival benefit.

Camouflaged Hybrid Cancer Cell-Platelet Fusion Membrane Nanovesicles Deliver Therapeutic MicroRNAs to Presensitize Triple-Negative Breast Cancer to Doxorubicin

Camouflaged cell-membrane-based nanoparticles have been gaining increasing attention owing to their improved biocompatibility and immunomodulatory properties. Using nanoparticles prepared from the membranes of specific cell types, or fusions derived from different cells membranes, can improve their functional performance in several aspects. Here, we used cell membranes extracted from breast cancer cells and platelets to fabricate a hybrid-membrane vesicle fusion (cancer cell-platelet-fusion-membrane vesicle, CPMV) in which we loaded therapeutic microRNAs (miRNAs) for the treatment of triple-negative breast cancer (TNBC). We used a clinically scalable microfluidic platform for the fusion of cell membranes. The reconstitution process during synthesis allows for efficient loading of miRNAs into CPMVs. We systematically optimized the conditions for preparation of miRNA-loaded CPMVs and demonstrated their property of homing to source cells using in vitro experiments, and by therapeutic evaluation in vivo. In vitro, the CPMVs exhibited significant recognition of their source cells and avoided engulfment by macrophages. After systemic delivery in mice, the CPMVs showed a prolonged circulation time and site-specific accumulation at implanted TNBC-xenografts. The delivered antimiRNAs sensitized TNBCs to doxorubicin, resulting in an improved therapeutic response and survival rate. This strategy has considerable potential for clinical translation to improve personalized therapy for breast cancer and other malignancies.

Low pan-immune-inflammation-value predicts better chemotherapy response and survival in breast cancer patients treated with neoadjuvant chemotherapy

Blood-based biomarkers reflect systemic inflammation status and have prognostic and predictive value in solid malignancies. As a recently defined biomarker, Pan-Immune-Inflammation-Value (PIV) integrates different peripheral blood cell subpopulations. This retrospective study of collected data aimed to assess whether PIV may predict the pathological complete response (pCR) to neoadjuvant chemotherapy (NAC) in Turkish women with breast cancer. The study consisted of 743 patients with breast cancer who were scheduled to undergo NAC before attempting cytoreductive surgery. A pre-treatment complete blood count was obtained in the two weeks preceding NAC, and blood-based biomarkers were calculated from absolute counts of relevant cell populations. The pCR was defined as the absence of tumor cells in both the mastectomy specimen and lymph nodes. Secondary outcome measures included disease-free survival (DFS) and overall survival (OS). One hundred seven patients (14.4%) had pCR. In receiver operating characteristic analysis, optimal cut-off values for the neutrophile-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte (PLR), PIV, and Ki-67 index were determined as ≥ 2.34, ≥ 0.22, ≥ 131.8, ≥ 306.4, and  ≥ 27, respectively. The clinical tumor (T) stage, NLR, MLR, PLR, PIV, estrogen receptor (ER) status, human epidermal growth factor receptor-2 (HER-2) status, and Ki-67 index were significantly associated with NAC response in univariate analyses. However, multivariate analysis revealed that the clinical T stage, PIV, ER status, HER-2 status, and Ki-67 index were independent predictors for pCR. Moreover, the low PIV group patients had significantly better DFS and OS than those in the high PIV group (p = 0.034, p = 0.028, respectively). Based on our results, pre-treatment PIV seems as a predictor for pCR and survival, outperforming NLR, MLR, PLR in predicting pCR in Turkish women with breast cancer who received NAC. However, further studies are needed to confirm our findings.

Inflammatory cell-associated tumors. Not only macrophages (TAMs), fibroblasts (TAFs) and neutrophils (TANs) can infiltrate the tumor microenvironment. The unique role of tumor associated platelets (TAPs)

It is well known that various inflammatory cells infiltrate cancer cells. Next to TAMs (tumor-associated macrophages), TAFs (tumor-associated fibroblasts) and TANs (tumor-associated neutrophils) also platelets form the tumor microenvironment. Taking into account the role of platelets in the development of cancer, we have decided to introduce a new term: tumor associated platelets-TAPs. To the best of our knowledge, thus far this terminology has not been employed by anyone. Platelets are the first to appear at the site of the inflammatory process that accompanies cancer development. Within the first few hours from the start of the colonization of cancer cells platelet-tumor aggregates are responsible for neutrophils recruitment, and further release a number of factors associated with tumor growth, metastasis and neoangiogenesis. On the other hand, it also has been indicated that factors delivered from platelets can induce a cytotoxic effect on the proliferating neoplastic cells, and even enhance apoptosis. Undoubtedly, TAPs' role seems to be more complex when compared to tumor associated neutrophils and macrophages, which do not allow for their division into TAP P1 and TAP P2, as in the case of TANs and TAMs. In this review we discuss the role of TAPs as an important element of tumor invasiveness and as a potentially new therapeutic target to prevent cancer development. Nevertheless, better exploring the interactions between platelets and tumor cells could help in the formulation of new therapeutic goals that support or improve the effectiveness of cancer treatment.

Aspirin and antiplatelet treatments in cancer

Platelets have been hypothesized to promote certain neoplastic malignancies; however, antiplatelet drugs are still not part of routine pharmacological cancer prevention and treatment protocols. Paracrine interactions between platelets and cancer cells have been implicated in potentiating the dissemination, survival within the circulation, and extravasation of cancer cells at distant sites of metastasis. Signals from platelets have also been suggested to confer epigenetic alterations, including upregulating oncoproteins in circulating tumor cells, and secretion of potent growth factors may play roles in promoting mitogenesis, angiogenesis, and metastatic outgrowth. Thrombocytosis remains a marker of poor prognosis in patients with solid tumors. Experimental data suggest that lowering of platelet count may reduce tumor growth and metastasis. On the basis of the mechanisms by which platelets could contribute to cancer growth and metastasis, it is conceivable that drugs reducing platelet count or platelet activation might attenuate cancer progression and improve outcomes. We will review select pharmacological approaches that inhibit platelets and may affect cancer development and propagation. We begin by presenting an overview of clinical cancer prevention and outcome studies with low-dose aspirin. We then review current nonclinical development of drugs targeted to platelet binding, activation, and count as potential mitigating agents in cancer.

Hybrid nanoparticle composites applied to photodynamic therapy: strategies and applications

Photodynamic therapy (PDT), as a robust strategy, has long been applied to cancer treatment owing to the meaningful breakthroughs and unique advantages, including ignorable invasiveness and spatio-temporal selectivity. Numerous PDT agents, especially hybrid nanoparticle composite (hybrid)-based sensitizers consisting of an organic polymer and inorganic nanoparticles (NPs), feature the synergetic pros of the components, which have unlocked the additional potentials of PDT. Although reviews relating to the applications of hybrids to PDT have been previously reported, most of them only focus on the designs of smart hybrids integrating multimodal imaging-guided multiple treatment modalities. Traditional PDT treatment has several limitations, such as inadequate PDT agents accumulating in cancer tissues, inferior PDT effect due to the devastating cancer hypoxia environment, relevant systemic toxicity in non-intelligent stimulation response treatment systems, and serious dependence of PDT on external light sources. Many strategies have been developed for overcoming these limitations, including improvement of cancer-homing ability by introducing active targeting groups, remodeling of the cancer hypoxia environment through oxygen regulators, intratumor release of ROS through activatable molecules, and replacement of laser light by X-rays or self-luminescence. This review aims to summarize the most recent advances in designing hybrids for improving the therapeutic efficacy of PDT.

Platelet-Mediated Protection of Cancer Cells From Immune Surveillance - Possible Implications for Cancer Immunotherapy

The growing insights in the complex interactions between metastatic cancer-cells and platelets have revealed that platelet tumor cell interactions in the blood stream are an important factor supporting tumor metastasis. An increased coagulability of platelets facilitates the vascular evasion and establishment of solid tumor metastasis. Furthermore, platelets can support an immunosuppressive tumor microenvironment or shield tumor cells directly from engagement of cytotoxic lymphocytes as e.g., natural killer (NK) cells. Platelets are both in the tumor microenvironment and systemically the quantitatively most important source of TGF-β, which is a key cytokine for immunosuppression in the tumor microenvironment. If similar platelet-tumor interactions are of physiological relevance in hematological malignancies remains less well-studied. This might be important, as T- and NK cell mediated graft vs. leukemia effects (GvL) are well-documented and malignant hematological cells have a high exposure to platelets compared to solid tumors. As NK cell-based immunotherapies gain increasing attention as a therapeutic option for patients suffering from hematological and other malignancies, we review the known interactions between platelets and NK cells in the solid tumor setting and discuss how these could also apply to hematological cancers. We furthermore explore the possible implications for NK cell therapy in patients with solid tumors and patients who depend on frequent platelet transfusions. As platelets have a protective and supportive effect on cancer cells, the impact of platelet transfusion on immunotherapy and the combination of immunotherapy with platelet inhibitors needs to be evaluated.

Platelets as messengers of early-stage cancer

Platelets have an important role in tumor angiogenesis, growth, and metastasis. The reciprocal interaction between cancer and platelets results in changes of several platelet characteristics. It is becoming clear that analysis of these platelet features could offer a new strategy in the search for biomarkers of cancer. Here, we review the human studies in which platelet characteristics (e.g., count, volume, protein, and mRNA content) are investigated in early-stage cancer. The main focus of this paper is to evaluate which platelet features are suitable for the development of a blood test that could detect cancer in its early stages.

Single-particle fibrinogen detection using platelet membrane-coated fluorescent polystyrene nanoparticles

Fibrinogen participates in many physiological processes and is a biomarker for a variety of diseases. On this account, the development of a sensitive method for fibrinogen assay is particularly important. Herein, we demonstrate a new color-coded single-particle detection (SPD) method for fibrinogen detection by using platelet membrane-coated fluorescent polystyrene nanoparticles (PNPs) as the probes. Due to the specific interactions between fibrinogen and integrin receptors on platelet membranes, PNPs can form aggregated structures in the presence of fibrinogen. Therefore, colocalization events between green and red PNPs and the corresponding Pearson's correlation coefficient vary with the concentrations of fibrinogen. The sensing ability shows a linear range of 30-300 μg mL^-1 and a limit of detection (LOD) of 3.9 μg mL^-1 (11.3 nM) for fibrinogen detection. Moreover, it has been validated that the proposed biosensor can selectively detect fibrinogen and shows a good performance in real sample applications.

Pre-radiotherapy lymphocyte count and platelet-to-lymphocyte ratio may improve survival prediction beyond clinical factors in limited stage small cell lung cancer: model development and validation

Background

Few small sample size studies have reported lymphocyte count was prognostic for survival in small-cell lung cancer (SCLC). This study aimed to validate this finding, to build prediction model for overall survival (OS) and to study whether novel models that combine lymphocyte-related variables can predict OS more accurately than a conventional model using clinical factors alone in a large cohort of limited-stage SCLC patients.

Methods

This study enrolled 544 limited-stage SCLC patients receiving definitive chemo-radiation with pre-radiotherapy lymphocyte-related variables including absolute lymphocyte count (ALC), platelet-to-lymphocyte ratio (P/L ratio), neutrophil-to-lymphocyte ratio (N/L ratio), and lymphocyte-to-monocyte ratio (L/M ratio). The primary endpoint was OS. These patients were randomly divided into a training dataset (n=274) and a validation dataset (n=270). Multivariate survival models were built in the training dataset, and the performance of these models were further tested in the validation dataset using the concordance index (C-index).

Results

The median follow-up time was 36 months for all patients. In the training dataset, univariate analysis showed that ALC (P=0.020) and P/L ratio (P=0.023) were significantly correlated with OS, while L/M ratio (P=0.091) and N/L ratio (P=0.436) were not. Multivariate modeling demonstrated the significance of ALC (P=0.063) and P/L ratio (P=0.003), and the improvement for OS prediction in combined models with the addition of ALC (C-index =0.693) or P/L ratio (C-index =0.688) over the conventional model (C-index =0.679). The validation dataset analysis confirmed a modest improvement of C-index with the addition of ALC or P/L ratio. All these models showed reasonable discriminations and calibrations.

Conclusions

This study validated the significant value of pre-radiotherapy ALC and P/L ratio on OS in limited-stage SCLC. The combined model with ALC or P/L ratio showed additional OS prediction values than the conventional model with clinical factors alone.

The Prognostic Value of Inflammation Factors in Hepatocellular Carcinoma Patients with Hepatic Artery Interventional Treatments: A Retrospective Study

Background

Hepatic artery interventional therapy has been recognized as the first choice for advanced liver cancer. However, reliable prognostic markers are still lacking. In the present study, we aimed to evaluate the prognostic value of inflammation factors including neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR) and monocyte to lymphocyte ratio (MLR) in hepatocellular carcinoma (HCC) patients with hepatic artery interventional treatments.

Methods

Patients undergoing hepatic artery interventional therapy after being diagnosed with HCC between 2007 and 2014 were enrolled. Pre-treatment NLR, PLR and MLR were calculated, and all factors including gender, age, TNM stage, BCLC staging, inflammation factors, LDH, ALP, CEA, AFP, hepatitis, liver cirrhosis, portal vein involvement, surgical history and hepatic artery interventional treatment on overall survival (OS) were evaluated by the univariate and multivariate Cox proportional hazards analyses.

Results

Overall, 407 patients were included. The optimal cutoff values determined by receiver operating characteristic (ROC) curve analyses for NLR, PLR and MLR were 3.82, 140.00 and 0.27, respectively. High NLR was associated with worse OS (median survival time: high NLR group 9 vs low NLR group 19 months, HR 1.842, 95% CI: 1.457–2.329, P<0.001). Elevated PLR was negatively correlated with OS (8 vs 18 months, HR 1.677, 95% CI: 1.302–2.161, P<0.001). Patients in high MLR group had a worse OS (10 vs 21 months, HR 1.626, 95% CI: 1.291–2.048, P<0.001). In multivariate analysis, NLR, LDH, ALP and portal vein involvement were independent prognostic factors for OS of HCC patients after hepatic artery interventional therapy. In addition, for patients in BCLC stage A and B, higher NLR, PLR and MLR were all significantly negatively correlated to median survival time (NLR: 17 vs 26 months, HR: 1.739 (95% CI: 1.279–2.365), P<0.001; PLR: 18 vs 26 months, HR: 1.681 (95% CI: 1.245–2.271), P=0.001; MLR: 20 vs 26 months, HR: 1.589 (95% CI: 1.185–2.129), P=0.002).

Conclusion

Elevated pre-treatment NLR, PLR and MLR were associated with worse survival time in HCC patients after hepatic artery interventional therapy. Among them, NLR was an independent prognostic factor for OS.

Retooling Cancer Nanotherapeutics' Entry into Tumors to Alleviate Tumoral Hypoxia

Anti-hypoxia cancer nanomedicine (AHCN) holds exciting potential in improving oxygen-dependent therapeutic efficiencies of malignant tumors. However, most studies regarding AHCN focus on optimizing structure and function of nanomaterials with presupposed successful entry into tumor cells. From such a traditional perspective, the main barrier that AHCN needs to overcome is mainly the tumor cell membrane. However, such an oversimplified perspective would neglect that real tumors have many biological, physiological, physical, and chemical defenses preventing the current state-of-the-art AHCNs from even reaching the targeted tumor cells. Fortunately, in recent years, some studies are beginning to intentionally focus on overcoming physiological barriers to alleviate hypoxia. In this Review, the limitations behind the traditional AHCN delivery mindset are addressed and the key barriers that need to be surmounted before delivery to cancer cells and some good ways to improve cell membrane attachment, internalization, and intracellular retention are summarized. It is aimed to contribute to Review literature on this emerging topic through refreshing perspectives based on this work and what is also learnt from others. This Review would therefore assist AHCNs researchers to have a quick overview of the essential information and glean thought-provoking ideas to advance this sub-field in cancer nanomedicine.

PODXL might be a new prognostic biomarker in various cancers: a meta-analysis and sequential verification with TCGA datasets

ABSRACT

BACKGROUND: Several studies have investigated the associations between the podocalyxin-like protein (PODXL) expression quantity or locations and cancers survival, but the results were far from conclusive. Therefore, we proceeded a meta-analysis on PODXL in various human cancers to find its prognostic value and followed confirmation using the TCGA datasets.

METHODS

We performed a systematic search, and 18 citations, including 5705 patients were pooled in meta-analysis. The results were verified with TCGA datasets.

RESULTS

Total eligible studies comprised 5705 patients with 10 types of cancer. And the result indicated that PODXL high-expression or membrane-expression were significantly related to poor overall survival (OS). However, subgroup analysis showed a significant association between high expressed PODXL and poor OS in the colorectal cancer, pancreatic cancer, urothelial bladder cancer, renal cell carcinoma and glioblastoma multiforme. Then, we validated the inference using TCGA datasets, and the consistent results were demonstrated in patients with pancreatic cancer, glioblastoma multiforme, gastric cancer, esophageal cancer and lung adenocarcinoma.

CONCLUSION

The result of meta-analysis showed that high expressed PODXL was significantly linked with poor OS in pancreatic cancer and glioblastoma multiforme, but not in gastric cancer, esophageal cancer or lung adenocarcinoma. And the membrane expression of PODXL might also associate with poor OS. PODXL may act as tumor promotor and may serve as a potential target for antitumor therapy.

Targeted gene silencing in vivo by platelet membrane-coated metal-organic framework nanoparticles

Small interfering RNA (siRNA) is a powerful tool for gene silencing that has been used for a wide range of biomedical applications, but there are many challenges facing its therapeutic use in vivo. Here, we report on a platelet cell membrane-coated metal-organic framework (MOF) nanodelivery platform for the targeted delivery of siRNA in vivo. The MOF core is capable of high loading yields, and its pH sensitivity enables endosomal disruption upon cellular uptake. The cell membrane coating provides a natural means of biointerfacing with disease substrates. It is shown that high silencing efficiency can be achieved in vitro against multiple target genes. Using a murine xenograft model, significant antitumor targeting and therapeutic efficacy are observed. Overall, the biomimetic nanodelivery system presented here provides an effective means of achieving gene silencing in vivo and could be used to expand the applicability of siRNA across a range of disease-relevant applications.

Cell-Based Nanoparticles Delivery Systems for Targeted Cancer Therapy: Lessons from Anti-Angiogenesis Treatments

The main strategy of cancer treatment has focused on attacking the tumor cells. Some cancers initially responsive to chemotherapy become treatment-resistant. Another strategy is to block the formation of tumor vessels. However, tumors also become resistant to anti-angiogenic treatments, mostly due to other cells and factors present in the tumor microenvironment, and hypoxia in the central part of the tumor. The need for new cancer therapies is significant. The use of nanoparticle-based therapy will improve therapeutic efficacy and targeting, while reducing toxicity. However, due to inefficient accumulation in tumor sites, clearance by reticuloendothelial organs and toxicity, internalization or conjugation of drug-loaded nanoparticles (NPs) into mesenchymal stem cells (MSCs) can increase efficacy by actively delivering them into the tumor microenvironment. Nanoengineering MSCs with drug-loaded NPs can increase the drug payload delivered to tumor sites due to the migratory and homing abilities of MSCs. However, MSCs have some disadvantages, and exosomes and membranes from different cell types can be used to transport drug-loaded NPs actively to tumors. This review gives an overview of different cancer approaches, with a focus on hypoxia and the emergence of NPs as drug-delivery systems and MSCs as cellular vehicles for targeted delivery due to their tumor-homing potential.

Integration of immunogenic activation and immunosuppressive reversion using mitochondrial-respiration-inhibited platelet-mimicking nanoparticles

Here, we developed platelet membranes (PM) as nano-carriers to co-encapsulate metformin (Met) and IR780 (PM-IR780-Met NPs). The resulting nano-carrier ensured a longer circulation lifetime and facilitated the greater accumulation of IR780 and Met in tumors owing to the active adhesion between PM and tumor cells. As a photodynamic therapy (PDT) agent, IR780 could effectively kill the tumor by producing toxic reactive singlet oxygen species (ROS), while the introduction of Met inhibited mitochondrial respiration and reduced tumor oxygen consumption, thereby evoking an oxygen-boosted PDT and propelling the immunogenic cell death (ICD)-based immunogenic pathway. Meanwhile, the reversed tumor hypoxia also impeded the myeloid derived suppressor cell (MDSC)-regulated immunosuppressive pathway. Finally, tremendous T cells were recruited and activated, providing a promising platform to eliminate the primary tumors and synchronously opening a new avenue for the effective ablation of tumor metastasis.

Cell membrane camouflaged nanoparticles: a new biomimetic platform for cancer photothermal therapy

Targeted drug delivery by nanoparticles (NPs) is an essential technique to achieve the ideal therapeutic effect for cancer. However, it requires large amounts of work to imitate the biomarkers on the surface of the cell membrane and cannot fully retain the bio-function and interactions among cells. Cell membranes have been studied to form biomimetic NPs to achieve functions like immune escape, targeted drug delivery, and immune modulation, which inherit the ability to interact with the in vivo environments. Currently, erythrocyte, leukocyte, mesenchymal stem cell, cancer cell and platelet have been applied in coating photothermal agents and anti-cancer drugs to achieve increased photothermal conversion efficiency and decreased side effects in cancer ablation. In this review, we discuss the recent development of cell membrane-coated NPs in the application of photothermal therapy and cancer targeting. The underlying biomarkers of cell membrane-coated nanoparticles (CMNPs) are discussed, and future research directions are suggested.

Suppression of Natural Killer cell NKG2D and CD226 anti-tumour cascades by platelet cloaked cancer cells: Implications for the metastatic cascade

Tumour cell immune evasion is a principal hallmark of successful metastasis. Tumour cells in the vasculature adopt a platelet cloak that efficiently suppresses the innate immune system by directly inhibiting Natural Killer (NK) cells, which normally function to neutralise spreading cancers. Here we describe two novel mechanisms of tumour cell evasion of NK cell anti-tumour functions. The first, an ‘immune decoy’ mechanism in which platelets induce the release of soluble NKG2D ligands from the tumour cell to mask detection and actively suppress NK cell degranulation and inflammatory cytokine (IFNγ) production, concomitantly. This represents a double-hit to immune clearance of malignant cells during metastasis. The second mechanism, a platelet-derived TGFβ-mediated suppression of the CD226/CD96-CD112/CD155 axis, is a novel pathway with poorly understood anti-cancer functions. We have demonstrated that platelets robustly suppress surface expression of CD226 and CD96 on the NK cell surface and their associated ligands on the tumour cell to further enhance NK cell suppression. These highly evolved mechanisms promote successful tumour immune evasion during metastasis and provide a unique opportunity for studying the complexity of cellular interactions in the metastatic cascade and thus novel targets for cancer immunotherapy.

Fibrin Nanoparticles Coupled with Keratinocyte Growth Factor Enhance the Dermal Wound-Healing Rate

Expediting the wound-healing process is critical for patients chronically ill from nonhealing wounds and diseases such as hemophilia or diabetes or who have suffered trauma including easily infected open wounds. FDA-approved external tissue sealants include the topical application of fibrin gels, which can be 500 times denser than natural fibrin clots. With lower clot porosity and higher polymerization rates than physiologically formed fibrin clots, the commercial gels quickly stop blood loss but impede the later clot degradation kinetics and thus retard tissue-healing rates. The fibrin nanoparticles (FBNs) described here are constructed from physiologically relevant fibrin concentrations that support new tissue and dermal wound scaffold formation when coupled with growth factors. The FBNs, synthesized in a microfluidic droplet generator, support cell adhesion and traction generation, and when coupled to keratinocyte growth factor (KGF), support cell migration and in vivo wound healing. The FBN-KGF particles enhance cell migration in vitro greater than FBN alone or free KGF and also improve healing outcomes in a murine full thickness injury model compared to saline, bulk fibrin sealant, free KGF, or bulk fibrin mixed with KGF treatments. Furthermore, FBN can be potentially administered with other tissue-healing factors and inflammatory mediators to improve wound-healing outcomes.

Platelets in cancer development and diagnosis

Platelets are involved in the development and progression of cancer through several mechanisms. Platelet activation at the site of tissue damage contributes to the initiation of a cascade of events which promote tumorigenesis. In fact, platelets release a wide array of proteins, including growth and angiogenic factors, lipids and extracellular vesicles rich in genetic material, which can mediate the induction of phenotypic changes in target cells, such as immune, stromal and tumor cells, and promote carcinogenesis and metastasis formation. Importantly, the role of platelets in tumor immune escape has been described. These lines of evidence open the way to novel strategies to fight cancer based on the use of antiplatelet agents. In addition to their ability to release factors, platelets are able of up-taking proteins and genetic material present in the bloodstream. Platelets are like 'sentinels' of the disease state. The evaluation of proteomics and transcriptomics signature of platelets and platelet-derived microparticles could represent a new strategy for the development of biomarkers for early cancer detection and/or therapeutic drug monitoring in cancer chemotherapy. Owing to the ability of platelets to interact with cancer cells and to deliver their cargo, platelets have been proposed as a 'biomimetic drug delivery system' for anti-tumor drugs to prevent the occurrence of off-target adverse events associated with the use of traditional chemotherapy.

Platelet-mimicking nanoparticles co-loaded with W18O49 and metformin alleviate tumor hypoxia for enhanced photodynamic therapy and photothermal therapy

W₁₈O₄₉-mediated photodynamic therapy (PDT) and photothermal therapy (PTT) are limited by the easily oxidized property and tumor hypoxia. Here, we report the development of platelet membranes as nanocarriers to co-load W₁₈O₄₉ nanoparticles (NPs) and metformin (PM-W₁₈O₄₉-Met NPs). Platelet membranes can protect W₁₈O₄₉ from oxidation and immune evasion, and increase the accumulation of W₁₈O₄₉ in tumor sites via the passive EPR effect and active adhesion between platelets and cancer cells. The introduction of metformin (Met), a typical anti-diabetic drug, can alleviate the tumor hypoxia through reducing oxygen consumption. As a result, ROS and heat generation are both greatly increased, as revealed by ROS/hypoxia imaging in vitro, IR thermal imaging in vivo and PET imaging in vivo. PM-W₁₈O₄₉-Met NPs show the improved therapeutic effects with greatly inhibited tumor growth and induced tumor cell apoptosis. Therefore, our work provides a novel strategy for simultaneous enhanced PDT and PTT, which is promising in bioapplication. STATEMENTE OF SIGNIFICANCE: W₁₈O₄₉-mediated photodynamic therapy and photothermal therapy are limited by the poor delivery of nanoparticles to tumors, the easily oxidized property, and tumor hypoxia environment, which will induce tumor treatment failure. Herein, we report the development of platelet membranes as nanocarriers to co-load W₁₈O₄₉ nanoparticles and metformin (PM-W₁₈O₄₉-Met NPs). Platelet membranes can protect W₁₈O₄₉ from oxidation and immune evasion, and increase the accumulation of W₁₈O₄₉ in tumor sites via the passive EPR effect and active adhesion. Metformin can alleviate the tumor hypoxia through reducing oxygen consumption. Hence, ROS and heat generation are both greatly increased. PM-W₁₈O₄₉-Met NPs show the improved therapeutic effects with greatly inhibited tumor growth and induced apoptosis. Therefore, our work provides a novel strategy in bioapplication.

Recent Advances of Membrane-Cloaked Nanoplatforms for Biomedical Applications

In terms of the extremely small size and large specific surface area, nanomaterials often exhibit unusual physical and chemical properties, which have recently attracted considerable attention in bionanotechnology and nanomedicine. Currently, the extensive usage of nanotechnology in medicine holds great potential for precise diagnosis and effective therapeutics of various human diseases in clinical practice. However, a detailed understanding regarding how nanomedicine interacts with the intricate environment in complex living systems remains a pressing and challenging goal. Inspired by the diversified membrane structures and functions of natural prototypes, research activities on biomimetic and bioinspired membranes, especially for those cloaking nanosized platforms, have increased exponentially. By taking advantage of the flexible synthesis and multiple functionality of nanomaterials, a variety of unique nanostructures including inorganic nanocrystals and organic polymers have been widely devised to substantially integrate with intrinsic biomoieties such as lipids, glycans, and even cell and bacteria membrane components, which endow these abiotic nanomaterials with specific biological functionalities for the purpose of detailed investigation of the complicated interactions and activities of nanomedicine in living bodies, including their immune response activation, phagocytosis escape, and subsequent clearance from vascular system. In this review, we summarize the strategies established recently for the development of biomimetic membrane-cloaked nanoplatforms derived from inherent host cells (e.g., erythrocytes, leukocytes, platelets, and exosomes) and invasive pathogens (e.g., bacteria and viruses), mainly attributed to their versatile membrane properties in biological fluids. Meanwhile, the promising biomedical applications based on nanoplatforms inspired by diverse moieties, such as selective drug delivery in targeted sites and effective vaccine development for disease prevention, have also been outlined. Finally, the potential challenges and future prospects of the biomimetic membrane-cloaked nanoplatforms are also discussed.

Prognostic role of platelet to lymphocyte ratio in pancreatic cancers: A meta-analysis including 3028 patients

BACKGROUND

Platelet to lymphocyte ratio (PLR) was recently reported being associated with the prognosis of pancreatic cancer (PC), but the prognostic value of PLR in pancreatic cancer remains inconsistent. We conduct a meta-analysis to evaluate the prognostic role of PLR in patients with PC.

METHODS

PubMed, Embase, Cochrane Library, and Web of Science were systematically searched for eligible studies which investigated the relationship between PLR and clinical outcome of patients with pancreatic cancer. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to evaluate the prognostic role of PLR in overall survival (OS) and progression-free survival (PFS)/time to progression (TTP).

RESULTS

A total of 16 studies comprising 3028 patients with PC were enrolled in this meta-analysis. Pooled analysis demonstrated that elevated PLR predicted a poor OS (HR = 1.22, 95% CI: 1.09-1.36, P < .001). Prognostic role of PLR on OS were significant in subgroup of Asians (HR = 1.22, 95% CI: 1.11-1.34, P < .001), patients treated with chemotherapy (HR = 1.18, 95% CI: 1.04-1.35, P = .01) and mixed methods (HR = 1.29, 95% CI: 1.07-1.57, P = .009), American joint committee on cancer (AJCC) stage of III-IV (HR = 1.22, 95% CI: 1.09-1.36, P < .001), pathological subtype of pancreatic adenocarcinoma (HR = 1.21, 95% CI: 1.08-1.36, P = .001), and cut-off value of PLR ≥160 (HR = 1.48, 95% CI: 1.25-1.75, P < .001).

CONCLUSIONS

An elevated PLR is associated with unfavorable overall survival in patients with pancreatic cancer.

Immunohistochemical Analysis Using Antipodocalyxin Monoclonal Antibody PcMab-47 Demonstrates Podocalyxin Expression in Oral Squamous Cell Carcinomas

Podocalyxin is a CD34-related type I transmembrane protein that is highly glycosylated with N-glycan, O-glycan, and keratan sulfate. Podocalyxin was originally found in the podocytes of rat kidney and is reportedly expressed in many types of tumors, including brain tumors, colorectal cancers, and breast cancers. Overexpression of podocalyxin is an independent predictor of progression, metastasis, and poor outcome. We recently immunized mice with recombinant human podocalyxin, which was produced using LN229 glioblastoma cells, and produced a novel antipodocalyxin monoclonal antibody (mAb), PcMab-47, which reacts with endogenous podocalyxin-expressing cancer cell lines and normal cell lines independent of glycosylation in Western blot, flow cytometry, and immunohistochemical analyses. In this study, we performed immunohistochemical analysis against oral cancers using PcMab-47. PcMab-47-stained oral squamous cell carcinoma cells in a cytoplasmic pattern and detected 26/38 (68.4%) of oral squamous cell carcinoma cells on tissue microarrays. These results indicate that PcMab-47 is useful in detecting podocalyxin of oral cancers for immunohistochemical analysis.

Challenges and unanswered questions for the next decade of circulating tumour cell research in lung cancer

Since blood borne circulating tumour cells (CTCs) initially shed from the primary tumour can seed and initiate metastasis at distant sites a better understanding of the biology of CTCs and their dissemination could provide valuable information that could guide therapeutic intervention and real time monitoring of disease progression. Although CTC enumeration has provided a reliable prognostic readout for a number of cancers, including lung cancer, the precise clinical utility of CTCs remains to be established. The rarity of CTCs together with the vanishingly small amounts of nucleic acids present in a single cell as well as cell to cell heterogeneity has stimulated the development of a wide range of powerful cellular and molecular methodologies applied to CTCs. These technical developments are now enabling researchers to focus on understanding the biology of CTCs and their clinical utility as a predictive and pharmacodynamics markers. This review summarises recent advances in the field of CTC research with focus on technical and biological challenges as well the progress made towards clinical utility of characterisation of CTCs with emphasis on studies in lung cancer.

Overcoming immunosuppression in bone metastases

Bone metastases are present in up to 70% of advanced prostate and breast cancers and occur at significant rates in a variety of other cancers. Bone metastases can be associated with significant morbidity. The establishment of bone metastasis activates several immunosuppressive mechanisms. Hence, understanding the tumor-bone microenvironment is crucial to inform the development of novel therapies. This review describes the current standard of care for patients with bone metastatic disease and novel treatment options targeting the microenvironment. Treatments reviewed include immunotherapies, cryoablation, and targeted therapies. Combinatorial treatment strategies including targeted therapies and immunotherapies show promise in pre-clinical and clinical studies to overcome the suppressive environment and improve treatment of bone metastases.

Novel roles for podocalyxin in regulating stress myelopoiesis, Rap1a, and neutrophil migration

Podocalyxin (Podxl) is a CD34 orthologue and cell surface sialomucin reported to have roles in renal podocyte diaphragm slit development; vascular cell integrity; and the progression of blood, breast, and prostate cancers. Roles for Podxl during nonmalignant hematopoiesis, however, are largely undefined. We have developed a Vav-Cre Podxl knockout (KO) mouse model, and report on novel roles for Podxl in governing stress myelopoiesis. At steady state, Podxl expression among hematopoietic progenitor cells was low level but was induced by granulocyte colony-stimulating factor (G-CSF) in myeloid progenitors and by thrombopoietin in human stem cells. In keeping with low-level Podxl expression at steady state, Vav-Cre deletion of Podxl did not markedly alter peripheral blood cell levels. A G-CSF challenge in Podxl-KO mice, in contrast, hyperelevated peripheral blood neutrophil and monocyte levels. Podxl-KO also substantially heightened neutrophil levels after 5-fluorouracil myeloablation. These loss-of-function phenotypes were selective, and Podxl-KO did not alter lymphocyte, basophil, or eosinophil levels. Within bone marrow (and after G-CSF challenge), Podxl deletion moderately decreased colony forming units-granulocytes, eyrthrocytes, monocyte/macrophages, megakaryocytes and CD16/32^posCD11b^pos progenitors but did not affect Gr-1^pos cell populations. Notably, Podxl-KO did significantly heighten peripheral blood neutrophil migration capacities. To interrogate Podxl's action mechanisms, a co-immunoprecipitation plus liquid chromatography-mass spectrometry approach was applied using hematopoietic progenitors from G-CSF-challenged mice. Rap1a, a Ras-related small GTPase, was a predominant co-retrieved Podxl partner. In bone marrow human progenitor cells, Podxl-KO led to heightened G-CSF activation of Rap1a^GTP, and Rap1a^GTP inhibition attenuated Podxl-KO neutrophil migration. Studies have revealed novel roles for Podxl as an important modulator of neutrophil and monocyte formation and of Rap1a activation during stress hematopoiesis.

PcMab-47: Novel Antihuman Podocalyxin Monoclonal Antibody for Immunohistochemistry

Podocalyxin (PODXL) is a CD34-related sialomucin and a well-known marker of embryonic stem cells. PODXL is expressed in many types of tumors including colorectal cancers, breast cancers, and brain tumors. Overexpression of PODXL is an independent predictor of progression, metastasis, and poor outcome. PODXL is also expressed in many normal cells such as renal podocytes and endothelial cells (ECs). However, high-sensitive and high-specific anti-PODXL monoclonal antibodies (mAbs) have not been established. Herein, we immunized mice with recombinant human PODXL, which was produced using LN229 glioblastoma cells. The anti-PODXL mAb, PcMab-47, reacted with endogenous PODXL-expressing cancer cell lines and normal cells independently of glycosylation in flow cytometry. Immunohistochemical analysis showed that PcMab-47 detected PODXL-expressing normal cells such as podocytes of kidney or ECs. Furthermore, PcMab-47 stained PODXL-expressing cancer cells of colon or breast cancers. These results suggest that PcMab-47 could be useful for investigating the expression and function of PODXL in cancers and normal tissues.

Data-Driven Discovery of Extravasation Pathway in Circulating Tumor Cells

Circulating tumor cells (CTCs) play a crucial role in cancer dissemination and provide a promising source of blood-based markers. Understanding the spectrum of transcriptional profiles of CTCs and their corresponding regulatory mechanisms will allow for a more robust analysis of CTC phenotypes. The current challenge in CTC research is the acquisition of useful clinical information from the multitude of high-throughput studies. To gain a deeper understanding of CTC heterogeneity and identify genes, pathways and processes that are consistently affected across tumors, we mined the literature for gene expression profiles in CTCs. Through in silico analysis and the integration of CTC-specific genes, we found highly significant biological mechanisms and regulatory processes acting in CTCs across various cancers, with a particular enrichment of the leukocyte extravasation pathway. This pathway appears to play a pivotal role in the migration of CTCs to distant metastatic sites. We find that CTCs from multiple cancers express both epithelial and mesenchymal markers in varying amounts, which is suggestive of dynamic and hybrid states along the epithelial-mesenchymal transition (EMT) spectrum. Targeting the specific molecular nodes to monitor disease and therapeutic control of CTCs in real time will likely improve the clinical management of cancer progression and metastases.

Undercover Agents: Targeting Tumours with Modified Platelets

Platelets have long been recognised to colocalise with tumour cells throughout haematogenous metastasis. Interactions between these cells contribute to tumour cell survival and motility through the vasculature into other tissues. Now, the research focus is shifting towards developing means to exploit this relationship to provide accurate diagnostics and therapies. Alterations to platelet count, RNA profile, and platelet ultrastructure are associated with the presence of certain malignancies, and may be used for cancer detection. Additionally, nanoparticle-based drug delivery systems are enhanced through the use of platelet membranes to specifically target cancer cells and camouflage the foreign particles from the immune system. This review discusses the development of platelets into highly powerful tools for cancer diagnostics and therapies.

Activated tumor cell integrin αvβ3 cooperates with platelets to promote extravasation and metastasis from the blood stream

Metastasis is the main cause of death in cancer patients, and understanding mechanisms that control tumor cell dissemination may lead to improved therapy. Tumor cell adhesion receptors contribute to cancer spreading. We noted earlier that tumor cells can expressing the adhesion receptor integrin αvβ3 in distinct states of activation, and found that cells which metastasize from the blood stream express it in a constitutively high affinity form. Here, we analyzed steps of the metastatic cascade in vivo and asked, when and how the affinity state of integrin αvβ3 confers a critical advantage to cancer spreading. Following tumor cells by real time PCR, non-invasive bioluminescence imaging, intravital microscopy and histology allowed us to identify tumor cell extravasation from the blood stream as a rate-limiting step supported by high affinity αvβ3. Successful transendothelial migration depended on cooperation between tumor cells and platelets involving the high affinity tumor cell integrin and release of platelet granules. Thus, this study identifies the high affinity conformer of integrin αvβ3 and its interaction with platelets as critical for early steps during hematogenous metastasis and target for prevention of metastatic disease.

Cancer and Thrombosis: The Platelet Perspective

Platelets are critical to hemostatic and immunological function, and are key players in cancer progression, metastasis, and cancer-related thrombosis. Platelets interact with immune cells to stimulate anti-tumor responses and can be activated by immune cells and tumor cells. Platelet activation can lead to complex interactions between platelets and tumor cells. Platelets facilitate cancer progression and metastasis by: (1) forming aggregates with tumor cells; (2) inducing tumor growth, epithelial-mesenchymal transition, and invasion; (3) shielding circulating tumor cells from immune surveillance and killing; (4) facilitating tethering and arrest of circulating tumor cells; and (5) promoting angiogenesis and tumor cell establishment at distant sites. Tumor cell-activated platelets also predispose cancer patients to thrombotic events. Tumor cells and tumor-derived microparticles lead to thrombosis by secreting procoagulant factors, resulting in platelet activation and clotting. Platelets play a critical role in cancer progression and thrombosis, and markers of platelet-tumor cell interaction are candidates as biomarkers for cancer progression and thrombosis risk.

Biointerfacing and Applications of Cell Membrane-Coated Nanoparticles

The cell membrane-coated nanoparticle is a biomimetic platform consisting of a nanoparticulate core coated with membrane derived from a cell, such as a red blood cell, platelet, or cancer cell. The cell membrane "disguise" allows the particles to be perceived by the body as the source cell by interacting with its surroundings using the translocated surface membrane components. The newly bestowed characteristics of the membrane-coated nanoparticle can be utilized for biological interfacing in the body, providing natural solutions to many biomedical issues. This Review will cover the interactions of these cell membrane-coated nanoparticles and their applications within three biomedical areas of interest, including (i) drug delivery, (ii) detoxification, and (iii) immune modulation.

Targeting ECM Disrupts Cancer Progression

Metastatic complications are responsible for more than 90% of cancer-related deaths. The progression from an isolated tumor to disseminated metastatic disease is a multistep process, with each step involving intricate cross talk between the cancer cells and their non-cellular surroundings, the extracellular matrix (ECM). Many ECM proteins are significantly deregulated during the progression of cancer, causing both biochemical and biomechanical changes that together promote the metastatic cascade. In this review, the influence of several ECM proteins on these multiple steps of cancer spread is summarized. In addition, we highlight the promising (pre-)clinical data showing benefits of targeting these ECM macromolecules to prevent cancer progression.

Circulating Tumor Cells: Who is the Killer?

This article is a critical note on the subject of Circulating Tumor Cells (CTC). It takes into account the tumor identity of Circulating Tumor Cells as cancer seeds in transit from primary to secondary soils, rather than as a “biomarker”, and considers the help this field could bring to cancer patients. It is not meant to duplicate information already available in a large number of reviews, but to stimulate considerations, further studies and development helping the clinical use of tumor cells isolated from blood as a modern personalized, non-invasive, predictive test to improve cancer patients’ life. The analysis of CTC challenges, methodological bias and critical issues points out to the need of referring to tumor cells extracted from blood without any bias and identified by cytopathological diagnosis as Circulating Cancer Cells (CCC). Finally, this article highlights recent developments and identifies burning questions which should be addressed to improve our understanding of the domain of CCC and their potential to change the clinical practice.