Effect of mono-guanidine-like derivatives on platelet aggregation and tumour cell induced platelet aggregation

Antiplatelet agents are the cornerstone for the treatment and prevention of cardiovascular diseases. However, they can induce severe side effects such as gastrointestinal bleeding. The main aim of this study is to determine the effect that novel guanidine-based derivatives exert on platelet aggregation. From a screening, in collaboration with the Psychoactive Drug Screening Project service of several compounds from our in-house library of α2-adrenoceptors' ligands, four compounds showed high to medium affinity towards α2C-adrenoceptors and H2 histamine receptors. Based on the structure of these compounds, another two in-house α2-adrenoceptors' ligands were also selected. The effect of the six compounds on platelet aggregation was investigated by light transmission aggregometry and optical microscopy. Flow cytometry was used to analyse their effect on platelet activation by measuring the expression of GPIIb/IIIa and P-selectin platelet receptors. Finally, the potential effect of those compounds on tumour cell-induced platelet aggregation was studied on three cancer cell lines from different origins using optical microscopy. We found that three of these compounds, with very good affinity towards H2 histamine receptors, significantly inhibited platelet aggregation, induced by both ADP and collagen, at the highest concentrations tested, and that tumour cell-induced platelet aggregation was also modulated by these derivatives. Our findings suggest that these aryl guanidine-like systems have an antiplatelet effect that could be also beneficial to reduce tumour cell-platelet interactions.

Inhibition of THBS1 axis contributes to the antitumor effect of PA-MSHA in anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is the most aggressive form of thyroid cancer, has the worst prognosis, and lacks effective treatment in clinical practice. Thrombospondin-1 (THBS1) is a multifunctional extracellular matrix (ECM) glycoprotein that regulates cell proliferation, apoptosis, and metastasis, and is considered a potential clinical biomarker for the monitoring and prognostication of various tumors. However, the specific roles and molecular mechanisms of action of THBS1 in ATC remain unclear. In this study, we found that Pseudomonas aeruginosa-mannose sensitive hemagglutinin (PA-MSHA), a THBS1 inhibitor, significantly inhibited ATC tumor growth both in vitro and in vivo. Mechanistically, we demonstrated that THBS1 was the target gene of PA-MSHA in ATC and identified the THBS1/FAK/AKT axis as the key antitumor signaling pathway. Furthermore, we confirmed that THBS1 was overexpressed in ATC tumors and that high levels of THBS1 were associated with a poorer prognosis in thyroid cancer. Silencing THBS1 significantly decreased p-FAK and p-AKT levels, resulting in significant inhibition of cell proliferation and apoptosis in ATC cells. These findings suggest that the THBS1/FAK/AKT axis is a promising therapeutic target for ATC treatment.

Clusterin mediates hydroquinone-induced cytotoxic responses in HL-60 differentiated cells

Benzene is a crucial industrial hydrocarbon, posing significant health risks due to its toxic metabolites like hydroquinone (HQ). This study investigates the role of clusterin (CLU) in benzene toxicity by analyzing its protein and mRNA levels, as well as the expression of Bcl-2 and Bax, to evaluate the feasibility of CLU as a biomarker for chronic benzene poisoning. HL-60 cells were induced to differentiate into neutrophil-like cells using 1% Dimethyl Sulfoxide (DMSO). Enzyme-linked immunosorbent assay (ELISA) and RT-PCR were used to analyze CLU protein and mRNA levels. ELISA was employed to detect sCLU protein content in cell culture supernatants, and western blot was used to assess Bcl-2 and Bax expression. The optimal time for 1% DMSO to induce HL-60 cells into neutrophil-like cells was 48 h. As HQ concentration increased, HL-60 cell viability decreased, CLU protein and sCLU protein levels in the supernatant decreased, CLU mRNA levels decreased, Bcl-2 protein expression decreased, and Bax expression increased. HQ exposure reduces CLU protein concentration and mRNA levels in neutrophil-like cells induced from HL-60 cells, indicating that CLU could be a potential biomarker for chronic benzene poisoning.

Advancements in precision nanomedicine design targeting the anoikis-platelet interface of circulating tumor cells

Tumor metastasis, the apex of cancer progression, poses a formidable challenge in therapeutic endeavors. Circulating tumor cells (CTCs), resilient entities originating from primary tumors or their metastases, significantly contribute to this process by demonstrating remarkable adaptability. They survive shear stress, resist anoikis, evade immune surveillance, and thwart chemotherapy. This comprehensive review aims to elucidate the intricate landscape of CTC formation, metastatic mechanisms, and the myriad factors influencing their behavior. Integral signaling pathways, such as integrin-related signaling, cellular autophagy, epithelial-mesenchymal transition, and interactions with platelets, are examined in detail. Furthermore, we explore the realm of precision nanomedicine design, with a specific emphasis on the anoikis‒platelet interface. This innovative approach strategically targets CTC survival mechanisms, offering promising avenues for combatting metastatic cancer with unprecedented precision and efficacy. The review underscores the indispensable role of the rational design of platelet-based nanomedicine in the pursuit of restraining CTC-driven metastasis.

Afatinib plus PEM and CBDCA overcome osimertinib resistance in EGFR-mutated NSCLC with high thrombospondin-1 expression

Osimertinib induces a marked response in non-small-cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) gene mutations. However, acquired resistance to osimertinib remains an inevitable problem. In this study, we aimed to investigate osimertinib-resistant mechanisms and evaluate the combination therapy of afatinib and chemotherapy. We established osimertinib-resistant cell lines (PC-9-OR and H1975-OR) from EGFR-mutant lung adenocarcinoma cell lines PC-9 and H1975 by high exposure and stepwise method. Combination therapy of afatinib plus carboplatin (CBDCA) and pemetrexed (PEM) was effective in both parental and osimertinib-resistant cells. We found that expression of thrombospondin-1 (TSP-1) was upregulated in resistant cells using cDNA microarray analysis. We demonstrated that TSP-1 increases the expression of matrix metalloproteinases through integrin signaling and promotes tumor invasion in both PC-9-OR and H1975-OR, and that epithelial-to-mesenchymal transition (EMT) was involved in H1975-OR. Afatinib plus CBDCA and PEM reversed TSP-1-induced invasion ability and EMT changes in resistant cells. In PC-9-OR xenograft mouse models (five female Balb/c-Nude mice in each group), combination therapy strongly inhibited tumor growth compared with afatinib monotherapy (5 mg/kg, orally, five times per week) or CBDCA (75 mg/kg, intraperitoneally, one time per week) + PEM (100 mg/kg, intraperitoneally, one time per week) over a 28-day period. These results suggest that the combination of afatinib plus CBDCA and PEM, which effectively suppresses TSP-1 expression, may be a promising option in EGFR-mutated NSCLC patients after the acquisition of osimertinib resistance.

Tumor-educated platelets

Beyond traditional roles in homeostasis and coagulation, growing evidence suggests that platelets also reflect malignant transformation in cancer. Platelets are present in the tumor microenvironment where they interact with cancer cells. This interaction results in direct and indirect "education" as evident by platelet alterations in adhesion molecules, glycoproteins, nucleic acids, proteins and various receptors. Subsequently, these tumor-educated platelets (TEPs) circulate throughout the body and play pivotal roles in promotion of tumor growth and dissemination. Accordingly, platelet status can be considered a unique blood-based biomarker that can potentially predict prognosis and therapeutic success. Recently, liquid biopsies including TEPs have received much attention as safe, minimally invasive and sensitive alternatives for patient management. Herein, we provide an overview of TEPs and explore their benefits and limitations in cancer.

Platelet membrane-derived microparticles may be biomarkers in patients with hepatocellular carcinoma and can promote the invasion and metastasis of hepatoma carcinoma cells

BACKGROUND

Platelet membrane-derived microparticles (PMPs) released by apheresis platelets (APs) during storage are involved in immunomodulatory and tumor processes. However, few studies have emphasized the relationship between PMPs and hepatocellular carcinoma (HCC).

METHODS

Enzyme-linked immunosorbent assay (ELISA) was used to detect PMPs in the plasma of HCC patients and healthy individuals. ELISA and flow cytometry were separately applied to analyze the variation in PMPs from APs prepared after 0, 3, 5, and 7 days of storage. Transwell was used to demonstrate the effects of PMPs on the invasion and migration of HCC cells. HCC-related indicators and invasion and migration-related markers were detected in vivo.

RESULTS

We found the amount of PMPs was significantly increased in HCC patients. There was also a significant difference in the amount of PMPs in APs with prolonged storage time. Further, the PMPs in D5 promoted the invasion and migration of HepG2 and Huh7 cells. Transcriptomics revealed striking differences in the expression of many tumor metastasis associated genes with PMPs treatment. PMPs promoted tumor growth and weight loss in HCC-bearing mice, and Western blot results showed that invasion and migration-related indicators also increase.

CONCLUSION

The content of PMPs in the plasma of HCC patients increases, and it can also promote the invasion and migration of HCC.

The role and function of CLU in cancer biology and therapy

Clusterin (CLU) is a highly evolutionary conserved glycoprotein with multiple isoform-specific functions and is widely distributed in different species. Accumulated evidence has shown the prominent role of CLU in regulating several essential physiological processes, including programmed cell death, metastasis, invasion, proliferation and cell growth via regulating diverse signaling pathways to mediate cancer progression in various cancers, such as prostate, breast, lung, liver, colon, bladder and pancreatic cancer. Several studies have revealed the potential benefit of inhibiting CLU in CLU inhibition-based targeted cancer therapies in vitro, in vivo or in human, suggesting CLU is a promising therapeutic target. This review discusses the multiple functions and mechanisms of CLU in regulating tumor progression of various cancers and summarizes the inhibitors of CLU used in CLU inhibition-based targeted cancer therapies.

The Ins and Outs of Clusterin: Its Role in Cancer, Eye Diseases and Wound Healing

Clusterin (CLU) is a glycoprotein originally discovered in 1983 in ram testis fluid. Rapidly observed in other tissues, it was initially given various names based on its function in different tissues. In 1992, it was finally named CLU by consensus. Nearly omnipresent in human tissues, CLU is strongly expressed at fluid-tissue interfaces, including in the eye and in particular the cornea. Recent research has identified different forms of CLU, with the most prominent being a 75-80 kDa heterodimeric protein that is secreted. Another truncated version of CLU (55 kDa) is localized to the nucleus and exerts pro-apoptotic activities. CLU has been reported to be involved in various physiological processes such as sperm maturation, lipid transportation, complement inhibition and chaperone activity. CLU was also reported to exert important functions in tissue remodeling, cell-cell adhesion, cell-substratum interaction, cytoprotection, apoptotic cell death, cell proliferation and migration. Hence, this protein is sparking interest in tissue wound healing. Moreover, CLU gene expression is finely regulated by cytokines, growth factors and stress-inducing agents, leading to abnormally elevated levels of CLU in many states of cellular disturbance, including cancer and neurodegenerative conditions. In the eye, CLU expression has been reported as being severely increased in several pathologies, such as age-related macular degeneration and Fuch's corneal dystrophy, while it is depleted in others, such as pathologic keratinization. Nevertheless, the precise role of CLU in the development of ocular pathologies has yet to be deciphered. The question of whether CLU expression is influenced by these disorders or contributes to them remains open. In this article, we review the actual knowledge about CLU at both the protein and gene expression level in wound healing, and explore the possibility that CLU is a key factor in cancer and eye diseases. Understanding the expression and regulation of CLU could lead to the development of novel therapeutics for promoting wound healing.

Platelet-Lymphocyte and Neutrophil-Lymphocyte Ratios Are Prognostic Markers for Pheochromocytomas and Paragangliomas

CONTEXT

Preoperative inflammatory markers, such as the neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and lymphocyte-monocyte ratio (LMR), have recently been proposed as prognostic markers in different tumors. However, their predictive values in patients with pheochromocytomas and paragangliomas (PPGLs) are uncertain.

OBJECTIVE

This study aimed to investigate the prognostic significance of inflammatory biomarkers in PPGL patients.

METHODS

Data from 1247 consecutive PPGL patients between 2002 and 2020 were evaluated. The preoperative inflammatory markers were evaluated. The prognostic roles were identified by X-tile software, Kaplan-Meier curves, and Cox regression models.

RESULTS

A total of 728 patients were included in the analysis, with a median follow-up of 63 months (IQR, 31-111 months); 31 individuals died, 28 patients developed metastases, and 12 patients developed recurrence. Our study showed that deaths were observed significantly more frequently in patients with high NLR(≥3.5) and high PLR (≥217.4) than those with low NLR (<3.5) (P = .003) and low PLR (<217.4) (P = .005). Elevated NLR (≥3.5) and elevated PLR (≥217.4) was significantly associated with decreased overall survival (OS) (P = .005), and elevated PLR (≥238.3) was significantly associated with decreased metastasis-free survival (MFS) (P = .021). Cox models illustrated that NLR and PLR were independent prognostic factors for OS, and PLR was an independent prognostic factor for MFS.

CONCLUSION

Both elevated NLR and PLR are associated with poor prognosis in PPGLs. They are convenient predictive markers that could be used in daily clinical practice.

Astrocyte senescence-like response related to peripheral nerve injury-induced neuropathic pain

BACKGROUND

Peripheral nerve damage causes neuroinflammation, which plays a critical role in establishing and maintaining neuropathic pain (NeP). The mechanisms contributing to neuroinflammation remain poorly elucidated, and pharmacological strategies for NeP are limited. Thus, in this study, we planned to explore the possible link between astrocyte senescence and NeP disorders following chronic sciatic nerve injury.

METHODS

An NeP animal model was established by inducing chronic constrictive injury (CCI) to the sciatic nerve in adult rats. A senolytic drug combination of dasatinib and quercetin was gavaged daily from the first postoperative day until the end of the study. Paw mechanical withdrawal threshold (PMWT) and paw thermal withdrawal latency (PTWL) were evaluated to assess behaviors in response to pain in the experimental rats. Senescence-associated β-galactosidase staining, western blot analysis, and immunofluorescence were applied to examine the levels of proinflammatory factors and severity of the senescence-like response in the spinal cord. Lipopolysaccharide (LPS) was administered to induce senescence of spinal astrocytes in primary cultures in vitro, to explore the potential impacts of senescence on the secretion of proinflammatory factors. Furthermore, single-cell RNA sequencing (scRNA-seq) was conducted to identify senescence-related molecular responses in spinal astrocytes under neuropathic pain.

RESULTS

Following sciatic nerve CCI, rats exhibited reduced PMWT and PTWL, increased levels of spinal proinflammatory factors, and an enhanced degree of senescence in spinal astrocytes. Treatment with dasatinib and quercetin effectively attenuated spinal neuroinflammation and mitigated the hypersensitivities of the rats subjected to sciatic nerve CCI. Mechanistically, the dasatinib-quercetin combination reversed senescence in LPS-stimulated primary cultured astrocytes and decreased the levels of proinflammatory factors. The scRNA-seq data revealed four potential senescence-related genes in the spinal astrocyte population, and the expression of clusterin (CLU) protein was validated via in vitro experiments.

CONCLUSION

The findings indicate the potential role of astrocyte senescence in neuroinflammation following peripheral nerve injury, and suggest that targeting CLU activation in astrocytes might provide a novel therapeutic strategy to treat NeP.

The clusterin connectome: Emerging players in chondrocyte biology and putative exploratory biomarkers of osteoarthritis

Introduction

Clusterin is amoonlighting protein that hasmany functions. It is amultifunctional Q6 holdase chaperone glycoprotein that is present intracellularly and extracellularly in almost all bodily fluids. Clusterin is involved in lipid transport, cell differentiation, regulation of apoptosis, and clearance of cellular debris, and plays a protective role in ensuring cellular survival. However, the possible involvement of clusterin in arthritic disease remains unclear. Given the significant potential of clusterin as a biomarker of osteoarthritis (OA), a more detailed analysis of its complex network in an inflammatory environment, specifically in the context of OA, is required. Based on the molecular network of clusterin, this study aimed to identify interacting partners that could be developed into biomarker panels for OA.

Methods

The STRING database and Cytoscape were used to map and visualize the clusterin connectome. The Qiagen Ingenuity Pathway Analysis (IPA) software was used to analyze and study clusterinassociated signaling networks in OA. We also analyzed transcription factors known to modulate clusterin expression, which may be altered in OA.

Results

The top hits in the clusterin network were intracellular chaperones, aggregate-forming proteins, apoptosis regulators and complement proteins. Using a text-mining approach in Cytoscape, we identified additional interacting partners, including serum proteins, apolipoproteins, and heat shock proteins.

Discussion

Based on known interactions with proteins, we predicted potential novel components of the clusterin connectome in OA, including selenoprotein R, semaphorins, and meprins, which may be important for designing new prognostic or diagnostic biomarker panels.

Platelet-derived microparticles stimulate the invasiveness of colorectal cancer cells via the p38MAPK-MMP-2/MMP-9 axis

BACKGROUND

Metastasis is the main cause of death in patients with colorectal cancer (CRC). Apart from platelets, platelet-derived microparticles (PMPs) are also considered important factors that can modify the activity of cancer cells. PMPs are incorporated by cancer cells and can also serve as intracellular signalling vesicles. PMPs are believed to affect cancer cells by upregulating their invasiveness. To date, there is no evidence that such a mechanism occurs in colorectal cancer. It has been shown that platelets can stimulate metalloproteases (MMPs) expression and activity via the p38MAPK pathway in CRC cells, leading to their elevated migratory potential. This study aimed to investigate the impact of PMPs on the invasive potential of CRC cells of various phenotypes via the MMP-2, MMP-9 and p38MAPK axis.

METHODS

We used various CRC cell lines, including the epithelial-like HT29 and the mesenchymal-like SW480 and SW620. Confocal imaging was applied to study PMP incorporation into CRC cells. The presence of surface receptors on CRC cells after PMP uptake was evaluated by flow cytometry. Transwell and scratch wound-healing assays were used to evaluate cell migration. The level of C-X-C chemokine receptor type 4 (CXCR4), MMP-2, and MMP-9 and the phosphorylation of ERK1/2 and p38MAPK were measured by western blot. MMP activity was determined using gelatine-degradation assays, while MMP release was evaluated by ELISA.

RESULTS

We found that CRC cells could incorporate PMPs in a time-dependent manner. Moreover, PMPs could transfer platelet-specific integrins and stimulate the expression of integrins already present on tested cell lines. While mesenchymal-like cells expressed less CXCR4 than epithelial-like CRC cells, PMP uptake did not increase its intensity. No significant changes in CXCR4 level either on the surface or inside CRC cells were noticed. Levels of cellular and released MMP-2 and MMP-9 were elevated in all tested CRC cell lines after PMP uptake. PMPs increased the phosphorylation of p38MAPK but not that of ERK1/2. Inhibition of p38MAPK phosphorylation reduced the PMP-induced elevated level and release of MMP-2 and MMP-9 as well as MMP-dependent cell migration in all cell lines.

CONCLUSIONS

We conclude that PMPs can fuse into both epithelial-like and mesenchymal-like CRC cells and increase their invasive potential by inducing the expression and release of MMP-2 and MMP-9 via the p38MAPK pathway, whereas CXCR4-related cell motility or the ERK1/2 pathway appears to not be affected by PMPs. Video Abstract.

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.

Effects of the interactions between platelets with other cells in tumor growth and progression

It has been confirmed that platelets play a key role in tumorigenesis. Tumor-activated platelets can recruit blood cells and immune cells to migrate, establish an inflammatory tumor microenvironment at the sites of primary and metastatic tumors. On the other hand, they can also promote the differentiation of mesenchymal cells, which can accelerate the proliferation, genesis and migration of blood vessels. The role of platelets in tumors has been well studied. However, a growing number of studies suggest that interactions between platelets and immune cells (e.g., dendritic cells, natural killer cells, monocytes, and red blood cells) also play an important role in tumorigenesis and tumor development. In this review, we summarize the major cells that are closely associated with platelets and discuss the essential role of the interaction between platelets with these cells in tumorigenesis and tumor development.

Cromolyn prevents cerebral vasospasm and dementia by targeting WDR43

Background

Cerebral vasospasm (CV) can cause inflammation and damage to neuronal cells in the elderly, leading to dementia.

Purpose

This study aimed to investigate the genetic mechanisms underlying dementia caused by CV in the elderly, identify preventive and therapeutic drugs, and evaluate their efficacy in treating neurodegenerative diseases.

Methods

Genes associated with subarachnoid hemorrhage and CV were acquired and screened for differentially expressed miRNAs (DEmiRNAs) associated with aneurysm rupture. A regulatory network of DEmiRNAs and mRNAs was constructed, and virtual screening was performed to evaluate possible binding patterns between Food and Drug Administration (FDA)-approved drugs and core proteins. Molecular dynamics simulations were performed on the optimal docked complexes. Optimally docked drugs were evaluated for efficacy in the treatment of neurodegenerative diseases through cellular experiments.

Results

The study found upregulated genes (including WDR43 and THBS1) and one downregulated gene associated with aneurysm rupture. Differences in the expression of these genes indicate greater disease risk. DEmiRNAs associated with ruptured aortic aneurysm were identified, of which two could bind to THBS1 and WDR43. Cromolyn and lanoxin formed the best docking complexes with WDR43 and THBS1, respectively. Cellular experiments showed that cromolyn improved BV2 cell viability and enhanced Aβ42 uptake, suggesting its potential as a therapeutic agent for inflammation-related disorders.

Conclusion

The findings suggest that WDR43 and THBS1 are potential targets for preventing and treating CV-induced dementia in the elderly. Cromolyn may have therapeutic value in the treatment of Alzheimer's disease and dementia.

A narrative review for platelets and their RNAs in cancers: New concepts and clinical perspectives

Recent years have witnessed a growing body of evidence suggesting that platelets are involved in several stages of the metastatic process via direct or indirect interactions with cancer cells, contributing to the progression of neoplastic malignancies. Cancer cells can dynamically exchange components with platelets in and out of blood vessels, and directly phagocytose platelets to hijack their proteome, transcriptome, and secretome, or be remotely regulated by metabolites or microparticles released by platelets, resulting in phenotypic, genetic, and functional modifications. Moreover, platelet interactions with stromal and immune cells in the tumor microenvironment lead to alterations in their components, including the ribonucleic acid (RNA) profile, and complicate the impact of platelets on cancers. A deeper understanding of the roles of platelets and their RNAs in cancer will contribute to the development of anticancer strategies and the optimization of clinical management. Encouragingly, advances in high-throughput sequencing, bioinformatics data analysis, and machine learning have allowed scientists to explore the potential of platelet RNAs for cancer diagnosis, prognosis, and guiding treatment. However, the clinical application of this technique remains controversial and requires larger, multicenter studies with standardized protocols. Here, we integrate the latest evidence to provide a broader insight into the role of platelets in cancer progression and management, and propose standardized recommendations for the clinical utility of platelet RNAs to facilitate translation and benefit patients.

Application progress of liquid biopsy in gastric cancer

Gastric cancer (GC) is one of the most common malignant tumors globally. Guiding the individualized treatment of GC is the focus of research. Obtaining representative biological samples to study the biological characteristics of GC is the focus of diagnosis and treatment of GC. Liquid biopsy technology can use high-throughput sequencing technology to detect biological genetic information in blood. Compared with traditional tissue biopsy, liquid biopsy can determine the dynamic changes of tumor. As a noninvasive auxiliary diagnostic method, liquid biopsy can provide diagnostic and prognostic information concerning the progression of the disease. Liquid biopsy includes circulating tumor cells, circulating tumor DNA, circulating tumor RNA, tumor educated platelets, exosomes, and cytokines. This article describes the classification of liquid biopsy and its application value in the occurrence, development, and therapeutic efficacy of GC.

Platelets and osteoblasts: secretome connections

Megakaryocyte hyperplasia associated with myeloproliferative neoplasms commonly leads to abnormal bone tissue deposition in the bone marrow, known as osteosclerosis. In this study, we aimed to synthesize the known proteomics literature describing factors released by megakaryocytes and platelets and to examine if any of the secreted factors have a known ability to stimulate the bone-forming cells, osteoblasts. Using a systematic search of Medline, we identified 77 articles reporting on factors secreted by platelets and megakaryocytes. After a full-text screening and analysis of the studies, we selected seven papers that reported proteomics data for factors secreted by platelets from healthy individuals. From 60 proteins reported in at least two studies, we focused on 23 that contained a putative signal peptide, which we searched for a potential osteoblast-stimulatory function. From nine proteins with a positive effect on osteoblast formation and function, two extracellular matrix (ECM) proteins, secreted protein acidic and rich in cysteine (SPARC) and tissue inhibitor of metalloproteinase-1 (TIMP1), and three cellular proteins with known extracellular function, the 70-kDa heat shock protein (HSP70), thymosin-β4 (TB4), and super dismutase (SOD), were identified as hypothetical candidate molecules to be examined as potential mediators in mouse models of osteomyelofibrosis. Thus, careful analysis of prior literature can be beneficial in assisting the planning of future experimental studies.

Emerging roles of platelets in cancer biology and their potential as therapeutic targets

The main role of platelets is to control bleeding and repair vascular damage via thrombosis. They have also been implicated to promote tumor metastasis through platelet-tumor cell interactions. Platelet-tumor cell interactions promote tumor cell survival and dissemination in blood circulation. Tumor cells are known to induce platelet activation and alter platelet RNA profiles. Liquid biopsies based on tumor-educated platelet biomarkers can detect tumors and correlate with prognosis, personalized therapy, treatment monitoring, and recurrence prediction. Platelet-based strategies for cancer prevention and tumor-targeted therapy include developing drugs that target platelet receptors, interfere with the release of platelet particles, inhibit platelet-specific enzymes, and utilize platelet-derived “nano-platelets” as a targeted drug delivery platform for tumor therapy. This review elaborates on platelet-tumor cell interactions and the molecular mechanisms and discusses future research directions for platelet-based liquid biopsy techniques and platelet-targeted anti-tumor strategies.

ECM stiffness-tuned exosomes drive breast cancer motility through thrombospondin-1

Breast cancer progression features ECM stiffening due to excess deposition and crosslinking of collagen, which dramatically influence tumor behaviour and fate. The mechanisms by which extracellular matrix (ECM) stiffening drives breast cancer invasion is an area of active research. Here we demonstrate the role of exosomes in ECM stiffness triggered breast cancer invasiveness. Using stiffness tuneable hydrogel ECM scaffolds, we show that stiff ECMs promote exosome secretion in a YAP/TAZ pathway-dependent manner. Interestingly, blocking exosome synthesis and secretion by GW4869 abrogated stiffness regulated motility and contractility in breast cancer cells. Reciprocally, exogenous addition of ECM stiffness-tuned exosomes orchestrated a series of changes in cell morphology, adhesion, protrusion dynamics resulting in fostered cell motility and invasion. Proteomic analysis of exosomal lysates followed by overrepresentation analysis and interactome studies revealed enrichment of cell adhesion and cell migration proteins in exosomes from stiff ECM cultures compared to that of soft ones. Quantitative proteomics of exosomes combined with genomic analysis of human breast tumor tissues (TCGA database) identified thrombospondin-1 (THBS1) as a prospective regulator of stiffness-dependent cancer invasion. Knockdown studies confirmed that the pro-invasive effects of stiffness-tuned exosomes are fuelled by exosomal THBS1. We further demonstrated that exosomal THBS1 mediates these stiffness-induced effects by engaging matrix metalloproteinase and focal adhesion kinase. Our studies establish the pivotal role of exosomal communication in ECM stiffness dependent cell migration with exosomal THBS1 as a master regulator of cancer invasion, which can be further exploited as a potential theranostic for improved breast cancer management.

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

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

Identification of Candidate Biomarkers and Prognostic Analysis in Colorectal Cancer Liver Metastases

Background

Colorectal cancer (CRC), one of the most common malignant tumors worldwide, has a high mortality rate, especially for patients with CRC liver metastasis (CLM). However, CLM pathogenesis remains unclear.

Methods

We integrated multiple cohort datasets and databases to clarify and verify potential key candidate biomarkers and signal transduction pathways in CLM. GEO2R, DAVID 6.8, ImageGP, STRING, UALCAN, ONCOMINE, THE HUMAN PROTEIN ATLAS, GEPIA 2.0, cBioPortal, TIMER 2.0, DRUGSURV, CRN, GSEA 4.0.3, FUNRICH 3.1.3 and R 4.0.3 were utilized in this study.

Results

Sixty-three pairs of matched colorectal primary cancer and liver metastatic gene expression profiles were screened from three gene expression profiles (GSE6988, GSE14297 and GSE81558). Thirty-one up-regulated genes and four down-regulated genes were identified from these three gene expression profiles and verified by another gene expression profiles (GSE 49355) and TCGA database. Two pathways (IGFBP-IGF signaling pathway and complement-coagulation cascade), eighteen key differentially expressed genes (DEGs), six hub genes (SPARCL1, CDH2, CP, HP, TF and SERPINA5) and two biomarkers (CDH2 and SPARCL1) with significantly prognostic values were screened by multi-omics data analysis and verified by Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) cohort.

Conclusions

In this study, we identified a robust set of potential candidate biomarkers in CLM, which would provide potential value for early diagnosis and prognosis, and would promote molecular targeting therapy for CRC and CLM.

Targeting TSP-1 decreased periodontitis by attenuating extracellular matrix degradation and alveolar bone destruction

An important factor in periodontitis pathogenesis relates to a network of interactions of various cytokines. Thrombospondin-1 (TSP-1) is upregulated in several inflammatory diseases. We previously found that Porphyromonas gingivalis lipopolysaccharide (P. gingivalis LPS)-induced TSP-1 production, and that TSP-1 simultaneously and effectively elevated inflammatory cytokines in THP-1 macrophages. This suggests that TSP-1 plays an important role in the pathology of periodontitis. However, the function of TSP-1 on oral cells is largely unknown. This study aimed to elucidate the underlying molecular mechanisms of TSP-1 in human periodontal fibroblasts (hPDLFs). We demonstrated that TSP-1 is highly expressed in the gingival crevicular fluid of patients with chronic periodontitis and in the inflammatory gingival tissues of rats. TSP-1 overexpression or treatment with recombinant human TSP-1(rTSP-1) promoted the expression of MMP-2, MMP-9 and RANKL/OPG in hPDLFs, while anti-TSP-1 inhibited cytokines production from P. gingivalis LPS-treated hPDLFs. Additional experiments showed that SB203580 (a special p38MAPK inhibitor) inhibited MMP-2, MMP-9 and RANKL/OPG expression induced by rTSP-1. Thus, TSP-1 effectively promoted P. gingivalis LPS-induced periodontal tissue (extracellular matrix (ECM) and alveolar bone) destruction by the p38MAPK signalling pathway, indicating that it may be a potential therapeutic target against periodontitis.

Curcumin and cancer biology: Focusing regulatory effects in different signalling pathways

Cancer is the second-leading cause of death worldwide. Till date, many such effective treatments are available, for example chemotherapy, surgery, and radiation therapy, but there are severe associated side effects, such as increased infection risk, constipation, hair loss, anaemia, among others. Thus, the need for effective therapeutic strategies and screening methodology arises. Researchers around the world are increasingly trying to discover anticancer therapies with as few side effects as possible and many are now focusing on phytochemicals, like curcumin. Curcumin is a bright yellow substance isolated from the plant rhizomes of Curcuma longa L. To this molecule a high therapeutic benefit has been underlined, being able to alter the development of cancer by different mechanisms, such as regulating multiple microRNA expression, modifying a series of signalling pathways, that is, Akt, Bcl-2, PTEN, p53, Notch, and Erbb. Another major pathway that curcumin targets is the matrix metalloproteinase (MMP) gene expression. In fact, MMPs are responsible for the degradation of the cell-extracellular matrix, which can lead to the diseased condition and many different pathways contribute to its activity, such as JAK/STAT, NF-κB, MAPK/ERK, COX-2, ROS, TGF-β, among others. In this review, we have attempted to describe the curcumin regulatory effect on different cell signalling pathways involved in the progression of different types of cancers.

Platelets in aging and cancer-"double-edged sword"

Platelets control hemostasis and play a key role in inflammation and immunity. However, platelet function may change during aging, and a role for these versatile cells in many age-related pathological processes is emerging. In addition to a well-known role in cardiovascular disease, platelet activity is now thought to contribute to cancer cell metastasis and tumor-associated venous thromboembolism (VTE) development. Worldwide, the great majority of all patients with cardiovascular disease and some with cancer receive anti-platelet therapy to reduce the risk of thrombosis. However, not only do thrombotic diseases remain a leading cause of morbidity and mortality, cancer, especially metastasis, is still the second cause of death worldwide. Understanding how platelets change during aging and how they may contribute to aging-related diseases such as cancer may contribute to steps taken along the road towards a "healthy aging" strategy. Here, we review the changes that occur in platelets during aging, and investigate how these versatile blood components contribute to cancer progression.

Thrombospondin-1 as a Potential Therapeutic Target: Multiple Roles in Cancers

Thrombospondin-1, an extracellular matrix protein, is the first identified natural angiogenesis inhibitor. Thrombospondin-1 participates in a great number of physiological and pathological processes, including cell-cell and cell-matrix interactions via a number of cell receptors, including CD36 and CD47, which plays a vital role in mediating inflammation and performs a promoting effect in pulmonary arterial vasculopathy and diabetes. Thrombospondin-1 consists of six domains, which combine with different molecules and participate in various functions in cancers, serving as a critical member in diverse pathways in cancers. Thrombospondin-1 works as a cancer promotor in some pathways but as a cancer suppressor in others, which makes it highly possible that its erroneous functioning might lead to opposite effects. Therefore, subdividing the roles of thrombospondin-1 and distinguishing them in cancers are necessary. Complex structure and multiple roles take disadvantage of the research and application of thrombospondin-1. Compared with the whole thrombospondin-1 protein, each thrombospondin- 1 active peptide performs an uncomplicated structure and, nevertheless, a specific role. In other words, various thrombospondin-1 active peptides may function differently. For instance, thrombospondin-1 could both promote and inhibit glioblastoma, which is significantly inhibited by the three type I repeats, a thrombospondin-1 active peptide but promoted by the fragment 167-569, a thrombospondin-1 active peptide consisting of the procollagen homology domain and the three type I repeats. Further studies of the functions of thrombospondin-1 active peptides and applying them reasonably are necessary. In addition to mediating cancerogenesis, thrombospondin-1 is also affected by cancer development, as reflected by its expression in plasma and the cancer tissue. Therefore, thrombospondin-1 may be a potential biomarker for pre-clinical and clinical application. This review summarizes findings on the multiple roles of thrombospondin-1 in cancer processes, with a focus on its use as a potential therapeutic target.

The role of the androgen receptor in prostate cancer-induced platelet aggregation and platelet-induced invasion

BACKGROUND

Metastatic prostate cancer progresses from a hormone sensitive androgen receptor expressing phenotype to a hormone insensitive androgen receptor-independent subtype with low overall survival. Human platelets contribute to metastasis via tumor cell-induced platelet aggregation, which in part enhances cancer cell invasion. Given the more aggressive nature of hormone insensitive prostate cancer, we hypothesized that androgen receptor-negative prostate cancer cells exhibit higher platelet aggregation potency and invasive response compared to cells with androgen receptor.

OBJECTIVE

To characterize the role of androgen receptors in prostate cancer-induced platelet aggregation and platelet-induced invasion.

METHODS

Tumor cell-induced platelet aggregation experiments were performed with platelets from healthy human donors and benign prostate (RWPE-1) and prostate cancer cell lines positive (LNCaP) and negative for androgen receptor (DU145 and PC3). Immunoblot measured prostate cancer prothrombin. Modified Boyden chamber invasion assays and zymography were performed to assess the effects of platelets on prostate cancer cell invasion and matrix metalloproteinase (MMP) expression, respectively.

RESULTS

Androgen receptor-positive prostate cancer cell lines failed to induce platelet aggregation. However, androgen receptor-inhibited and -negative cell lines all induced platelet aggregation, which was abolished by dabigatran. Androgen receptor-inhibited and -negative cell lines demonstrated greater expression of prothrombin than androgen receptor-positive cells. Platelets enhanced invasion and MMP-2 and -9 expression by androgen receptor-inhibited and negative prostate cancer cells, but not that of the androgen receptor-positive cells.

CONCLUSIONS

Androgen receptor loss within prostate cancer results in increased thrombogenicity due to upregulation of prothrombin expression. Reciprocally, platelets enhance invasion of androgen receptor-negative prostate cancer cells via increased MMP expression.

Impact of Deoxycholic Acid on Oesophageal Adenocarcinoma Invasion: Effect on Matrix Metalloproteinases

Bile acids (BAs) have been implicated in the development of oesophagitis, Barrett’s oesophagus and oesophageal adenocarcinoma (OAC). However, whether BAs promote cancer invasiveness has not been elucidated. We evaluated the role of BAs, in particular deoxycholic acid (DCA), in OAC invasion. Migration and invasiveness in untreated and BA-treated oesophageal SKGT-4 cancer cells were evaluated. Activity and expression of different matrix metalloproteinases (MMPs) were determined by zymography, ELISA, PCR and Western blot. Finally, human OAC tissues were stained for MMP-10 by immunohistochemistry. It was found that SKGT-4 cells incubated with low concentrations of DCA had a significant increase in invasion. In addition, MMP-10 mRNA and protein expression were also increased in the presence of DCA. MMP-10 was found to be highly expressed both in-vitro and in-vivo in neoplastic OAC cells relative to non-neoplastic squamous epithelial cells. Our results show that DCA promotes OAC invasion and MMP-10 overexpression. This study will advance our understanding of the pathophysiological mechanisms involved in human OAC and shows promise for the development of new therapeutic strategies.

THBS1 regulates trophoblast fusion through a CD36-dependent inhibition of cAMP, and its upregulation participates in preeclampsia

Preeclampsia is a pregnancy complication which threatens the survival of mothers and fetuses. It originates from abnormal placentation, especially insufficient fusion of the cytotrophoblast cells to form the syncytiotrophoblast. In this study, we found that THBS1, a matricellular protein that mediates cell-to-cell and cell-to-matrix interactions, is downregulated during the fusion of primary cytotrophoblast and BeWo cells, but upregulated in the placenta of pregnancies complicated by preeclampsia. Also, THBS1 was observed to interact with CD36, a membrane signal receptor and activator of the cAMP signaling pathway, to regulate the fusion of cytotrophoblast cells. Overexpression of THBS1 inhibited the cAMP signaling pathway and reduced the BeWo cells fusion ratio, while the effects of THBS1 were abolished by a CD36-blocking antibody. Our results suggest that THBS1 signals through a CD36-mediated cAMP pathway to regulate syncytialization of the cytotrophoblast cells, and that its upregulation impairs placental formation to cause preeclampsia. Thus, THBS1 can serve as a therapeutic target regarding the mitigation of abnormal syncytialization and preeclampsia.

The Different Facets of Liquid Biopsy: A Kaleidoscopic View

The current limitations of cancer diagnosis and molecular profiling based on invasive tissue biopsies or clinical imaging have led to the development of the liquid biopsy field. Liquid biopsy includes the isolation of circulating tumor cells (CTCs), circulating free or tumor DNA (cfDNA or ctDNA), extracellular vesicles (EVs), and tumor-educated platelets (TEPs) from body fluid samples and their molecular characterization to identify biomarkers for early cancer diagnosis, prognosis, therapeutic prediction, and follow-up. These innovative biosources show similar features as the primary tumor from where they originated or interacted. This review describes the different technologies and methods used for processing these biosources as well as their main clinical applications with their advantages and limitations.

Biomarkers of tumor invasiveness in proteomics (Review)

Over the past two decades, quantitative proteomics has emerged as an important tool for deciphering the complex molecular events involved in cancers. The number of references involving studies on the cancer metastatic process has doubled since 2010, while the last 5 years have seen the development of novel technologies combining deep proteome coverage capabilities with quantitative consistency and accuracy. To highlight key findings within this huge amount of information, the present review identified a list of tumor invasive biomarkers based on both the literature and data collected on a biocollection of experimental cell lines, tumor models of increasing invasiveness and tumor samples from patients with colorectal or breast cancer. Crossing these different data sources led to 76 proteins of interest out of 1,245 mentioned in the literature. Information on these proteins can potentially be translated into clinical prospects, since they represent potential targets for the development and evaluation of innovative therapies, alone or in combination. Herein, a systematical review of the biology of each of these proteins, including their specific subcellular/extracellular or multiple localizations is presented. Finally, as an important advantage of quantitative proteomics is the ability to provide data on all these molecules simultaneously in cell pellets, body fluids or paraffin‑embedded sections of tumors/invaded tissues, the significance of some of their interconnections is discussed.

Stage predictivity of neutrophil/lymphocyte and platelet/lymphocyte ratios in pancreatic neuroendocrine tumors

Objectives

This study aimed to analyze the correlations between European Neuroendocrine Tumor Society (ENEST), Tumor Node Metastasis (TNM) staging systems and pre-operative neutrophil/lymphocyte (NLR) and platelet/lymphocyte ratios (PLR) in patients with pancreatic neuroendocrine tumor (PNET).

Material and Methods

Forty-four patients with diagnosed PNET were analyzed retrospectively. Accordingly, the patients' blood and clinicopathological parameters were analyzed. The correlations between laboratory parameters and tumor stages were evaluated using Eta correlation analysis. The control group was composed of volunteering healthy participants who had similarities with our study group as regards age and gender.

Results

According to ENETS classification, 34% of the patients were stage I, 25% were stage II, 20.4% were stage III and 20.4% were stage IV. NLR and PLR mean values were 2.4 and 127, respectively. NLR values of the patients in the study group were higher than those of the control group (p= 0.001). NLR and PLR values of stage I, II, III and IV patients tended to increase in parallel to the higher stages according to ENETS system (p= 0.0001 and p= 0.0001, respectively). Similarly, NLR and PLR values increased in parallel to the higher stages according to TNM system (p= 0.0001 and p= 0.0001, respectively). In addition, NLR values were found to be higher in patients with lymph node metastasis than in those without (p= 0.001).

Conclusion

Increased levels of inflammatory mediators such as NLR and PLR are associated with advanced stages of patients with PNET.

The endothelial barrier and cancer metastasis: Does the protective facet of platelet function matter?

Overwhelming evidence suggests that platelets have a detrimental role in promoting cancer spread via platelet-cancer cell interactions linked to thrombotic mechanisms. On the other hand, a beneficial role of platelets in the preservation of the endothelial barrier in inflammatory conditions has been recently described, a phenomenon that could also operate in cancer-related inflammation. It is tempting to speculate that some antiplatelet strategies to combat cancer metastasis may impair the endogenous platelet-dependent mechanisms preserving endothelial barrier function. If the protective function of platelets is impaired, it may lead to increased endothelial permeability and more efficient cancer cell intravasation in the primary tumor and cancer cell extravasation at metastatic sites. In this commentary, we discuss current evidence that could support this hypothesis.

Tumor-educated platelet as liquid biopsy in lung cancer patients

Lung cancer is the most frequent cancer for males and third most frequent cancer for females. Targeted therapy drugs based on molecular alterations, such as angiogenesis inhibitors, epidermal growth factor receptor (EGFR) inhibitors, and anaplastic lymphoma kinase (ALK) inhibitors are important part of treatment of NSCLC. However, the quality of the available tumor biopsy and/or cytology material is sometimes not adequate to perform the necessary molecular testing, which has prompted the search for alternatives. This review examines the use of tumor-educated platelet (TEP) as a liquid biopsy in lung cancer patients. The development of sensitive and accurate techniques have made it possible to detect the specific genetic alterations for which targeted therapies are already available. Liquid biopsy offers opportunities to detect resistance mechanisms at an early stage. To conclude, tumor-educated platelet has the potential to be used as liquid biopsy for a variety of clinical and investigational applications.

Apolipoproteins and cancer

The role of apolipoproteins in cardiovascular disease has been well investigated, but their participation in cancer has only been explored in a few published studies which showed a close link with certain kinds of cancer. In this review, we focused on the function of different kinds of apolipoproteins in cancers, autophagy, oxidative stress, and drug resistance. The potential application of apolipoproteins as biomarkers for cancer diagnosis and prognosis was highlighted, together with an investigation of their potential as drug targets for cancer treatment. Many important roles of apolipoproteins and their mechanisms in cancers were reviewed in detail and future perspectives of apolipoprotein research were discussed.

Correlation of ERK/MAPK signaling pathway with proliferation and apoptosis of colon cancer cells

The role of extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) signaling pathway in the proliferation and apoptosis of human colon cancer cells was studied. The transduction process of ERK/MAPK signaling pathway was inhibited using methyl ethyl ketone (MEK) inhibitor U0126. Promoting effect of hepatocyte growth factor (HGF) on proliferation of human colon cancer cells was detected via Cell Counting Kit 8 (CCK8), the cycle and apoptosis of human colon cancer cells were detected via flow cytometry, and the migration of human colon cancer cells was detected via wound healing assay. The results revealed that after drug treatment for 48 h, there were statistically significant differences in 4 and 8 µmol/l U0126 experimental group compared with control group (P<0.05). Compared with those in control group, G1 phase, S phase, G2 phase and proliferation index (PI) in 2, 4 and 8 µmol/l U0126 group had statistically significant differences (P<0.05). There were statistically significant differences in comparison of G1 phase, S phase, G2 phase and PI between control and 8 µmol/l U0126 group (P<0.05). Compared with that in control group, the cell migration distance in 8 µmol/l U0126 group had a statistically significant difference after drug treatment for 24 h (P<0.05). After drug treatment for 48 and 72 h, the cell migration distance in 4 and 8 µmol/l U0126 group was significantly reduced, and the differences were statistically significant compared with that in control group (P<0.05). In conclusion, ERK/MAPK signaling pathway is involved in the effects of HGF of promoting proliferation and regulating cell cycle and apoptosis of human colon cancer cells, providing a new approach for the treatment of colon cancer.

Effect of Stromal Cells in Tumor Microenvironment on Metastasis Initiation

The cellular environment where tumor cells reside is called the tumor microenvironment (TME), which consists of borders, blood vessels, lymph vessels, extracellular matrix (ECM), stromal cells, immune/inflammatory cells, secreted proteins, RNAs and small organelles. By dynamically interacting with tumor cells, stromal cells participate in all stages of tumor initiation, progression, metastasis, recurrence and drug response, and consequently, affect the fate of patients. During the processes of tumor evolution and metastasis initiation, stromal cells in TME also experience some changes and play roles in both the suppression and promotion of metastasis, while the overall function of stromal cells is beneficial for cancer cell survival and movement. In this review, we examine the effects of stromal cells in TME on metastasis initiation, including angiogenesis, epithelial-mesenchymal transition (EMT) and invasion. We also highlight functions of proteins, RNAs and small organelles secreted by stromal cells in their influences on multiple stages of tumor metastasis.

Upregulation of HRD1 promotes cell migration and invasion in colon cancer

3-Hydroxy-3-methylglutaryl reductase degradation (HRD1) is an E3 ubiquitin ligase that functions by promoting degradation of misfolded proteins in processes such as embryogenesis and rheumatoid arthritis. However, little is known about the role of HRD1 in cancer. The aim of the present study was to investigate the expression pattern and functions of HRD1 in human colon cancer (CC). We found that HRD1 expression was increased significantly in human CC tissues, and its overexpression was associated with TNM stage, tumor differentiation, tumor invasive depth, and distant metastasis. Knockdown of HRD1 using small hairpin (sh) RNA plasmid significantly inhibited CC cell migration and invasion. Furthermore, the silencing of HRD1 decreased the expression of MMP-2 and MMP-9, which is critical for CC cell migration and invasion. Taken together, these results revealed that HRD1 is overexpressed in CC and promotes migration and invasion of CC cells. Inhibition of HRD1 may be considered as an effective anti-CC strategy.

Antithrombotic Agents and Cancer

Platelet activation is the first response to tissue damage and, if unrestrained, may promote chronic inflammation-related cancer, mainly through the release of soluble factors and vesicles that are rich in genetic materials and proteins. Platelets also sustain cancer cell invasion and metastasis formation by fostering the development of the epithelial-mesenchymal transition phenotype, cancer cell survival in the bloodstream and arrest/extravasation at the endothelium. Furthermore, platelets contribute to tumor escape from immune elimination. These findings provide the rationale for the use of antithrombotic agents in the prevention of cancer development and the reduction of metastatic spread and mortality. Among them, low-dose aspirin has been extensively evaluated in both preclinical and clinical studies. The lines of evidence have been considered appropriate to recommend the use of low-dose aspirin for primary prevention of cardiovascular disease and colorectal cancer by the USA. Preventive Services Task Force. However, two questions are still open: (i) the efficacy of aspirin as an anticancer agent shared by other antiplatelet agents, such as clopidogrel; (ii) the beneficial effect of aspirin improved at higher doses or by the co-administration of clopidogrel. This review discusses the latest updates regarding the mechanisms by which platelets promote cancer and the efficacy of antiplatelet agents.

Thrombospondin 2 promotes tumor metastasis by inducing matrix metalloproteinase-13 production in lung cancer cells

Thrombospondin (TSP)-2, a matricellular glycoprotein of the TSP family, regulates multiple biological functions, including proliferation, angiogenesis, cell adhesion, and extracellular matrix (ECM) modeling. The clinical relevance of TSP-2 has been explored in many different cancers. TSP-2 expression levels vary between different cancer types, and their role in tumor progression remains controversial. Although previous studies have reported higher serum TSP-2 levels in patients with non-small cell lung cancer, the role of TSP-2 in lung cancer progression remains to be addressed. A total of 585 lung adenocarcinoma datasets, including mRNA sequencing and clinical data, were retrieved from The Cancer Genome Atlas (TCGA). Forty paired adjacent normal tissues and lung tumor tissue datasets were used to examine TSP-2 expression levels. Tumor microarray were performed with immunohistochemical staining to examine TSP-2 expression in lung cancer patients. Transwell migration assay, quantitative real-time PCR and Western blot were used to investigate molecular mechanism of TSP-2 in lung cancer cell. TSP-2 promotes matrix metalloproteinase-13 (MMP-13) expression, cell migration, and cell invasion by mediating integrin αvβ3/FAK/Akt/NF-κB signal transduction. Using TSP-2 knockdown stable cell lines, we found that TSP-2 knockdown reduces MMP-13 expression and cell mobility. When we manipulated the tumor tissue microarray and TCGA datasets to investigate the clinical relevance of TSP-2, we found high TSP-2 expression levels in lung cancer specimens. The present study demonstrates that TSP-2 regulates cell mobility through MMP-13 expression in lung cancer cells. In addition, TSP-2 expression was associated with MMP-13 expression and poor prognosis in lung cancer. TSP-2 may therefore be a promising novel target for lung cancer treatment.

Poor prognostic role of the pretreatment platelet counts in colorectal cancer: A meta-analysis

BACKGROUND

Recently, a wide variety of studies have suggested that elevated platelet counts are associated with survival in patients with colorectal cancer. On one hand several studies suggest a negative connection in colorectal cancer patients with pre-operative thrombocytosis, on the other hand other studies contradicts this. However, it remains unknown whether elevated platelet counts are associated with survival in colorectal cancer patients. We therefore conducted this meta-analysis to evaluate the prognostic role of platelet counts in colorectal cancer.

METHODS

PubMed, Embase, and the Cochrane Library databases were searched from their inception to October 15, 2016 to identify relevant studies that have explored the prognostic role of platelet counts in colorectal cancer. Studies that examined the association between platelet counts and prognoses in colorectal cancer and that provided a hazard ratio (HR) and 95% confidence interval (CI) for overall survival (OS) and/or disease-free survival (DFS) were included.

RESULTS

This meta-analysis included 9 retrospective cohort studies involving 3413 patients with colorectal cancer. OS was shorter in patients with elevated platelet counts than in patients with normal counts (HR 2.11, 95% CI: 1.68-2.65). For DFS, an elevated platelet count was also a poor predictor (HR 2.51, 95% CI: 1.84-3.43).

CONCLUSION

In this meta-analysis, we suggest that an elevated platelet count is a negative predictor of survival in both primary colorectal cancer and resectable colorectal liver metastases.

MEG3 Activated by Vitamin D Inhibits Colorectal Cancer Cells Proliferation and Migration via Regulating Clusterin

The long non-coding RNA maternally expressed gene 3 (MEG3) is frequently dysregulated in human cancers; however, its roles in colorectal cancer (CRC) development are largely unknown. Here, we reported that MEG3 was down-regulated in CRC tissues and CRC patients with lower MEG3 showed poorer overall survival and disease-free survival than those with higher MEG3 level. MEG3 over-expression represses CRC cells proliferation and migration in vivo and in vitro, while MEG3 knockdown leads to the enhanced proliferation and metastasis of CRC cells. In CRC cells, MEG3 over-expression is related to decreased Clusterin mRNA and the corresponding protein levels, and it also directly binds to Clusterin protein through its 732–1174 region. In further, Clusterin over-expression rescues the compromised abilities of proliferation and metastasis induced by MEG3 over-expression, suggesting that MEG3 inhibits the CRC progression through regulating the Clusterin activities. Additionally, we found that 1α,25-(OH)₂D and vitamin D receptor (VDR) stimulate MEG3 expression in CRC cells through directly binding to its promoter. These results suggested that MEG3 functions as a tumor suppressor in CRC via regulating the Clusterin activities and may underlie the anticancer activities of vitamin D on CRC cells. The VDR/MEG3/Clusterin signaling pathway may serve as potential therapeutic targets and prognosis biomarkers for CRC patients in future.

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MEG3 serves as a novel CRC prognosis biomarker and a potential therapeutic target.

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MEG3 over-expression represses CRC cells proliferation and metastatic features.

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MEG3 has a role in Clusterin expression and activity down-regulation at transcriptional and post-transcriptional levels.

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VDR activated MEG3 expression via directly binding to MEG3 promoter.

Tunicamycin inhibits colon carcinoma growth and aggressiveness via modulation of the ERK-JNK-mediated AKT/mTOR signaling pathway

Epidemiology and evidence have demonstrated that colon carcinoma is one of the most common gastrointestinal tumors in the clinic. Reports have suggested that Tunicamycin significantly inhibits aggressiveness of colon carcinoma cells by promotion of apoptosis. In the present study, the inhibitory effect of tunicamycin on colon cancer cells and the potential underlying molecular mechanism was investigated. Western blotting, immunohistochemistry, apoptotic assays and immunofluorescence were used to analyze the therapeutic effects of tunicamycin on apoptosis, growth, aggressiveness and cell cycle of colon tumor cells, by downregulation of fibronectin, vimentin and E‑cadherin expression levels. In vitro experiments demonstrated that tunicamycin significantly inhibited growth, migration and invasion of colon carcinoma cells. In addition, tunicamycin administration promoted apoptosis of colon carcinoma cells via upregulation of apoptotic protease activating factor 1 and cytochrome c expression levels, which are proteins that have a role in mitochondrial apoptosis signaling. Cell cycle assays revealed that tunicamycin suppressed proliferation and arrested S phase entry of colon carcinoma cells. Mechanistic analysis demonstrated that tunicamycin reduced expression and phosphorylation levels of extracellular signal‑regulated kinase (ERK), c‑JUN N‑terminal kinase (JNK) and protein kinase B (AKT), and inhibited mammalian target of rapamycin (mTOR) expression levels in colon carcinoma cells. Endogenous overexpression of ERK inhibited tunicamycin‑mediated downregulation of JNK, AKT and mTOR expression, which further blocked tunicamycin‑mediated inhibition of growth and aggressiveness of colon carcinoma. In vivo assays revealed that tunicamycin treatment significantly inhibited tumor growth and promoted apoptosis, which led to long‑term survival of tumor‑bearing mice compared with the control group. In conclusion, these results suggested that tunicamycin may inhibit growth and aggressiveness of colon cancer via the ERK‑JNK‑mediated AKT/mTOR signaling pathway, and suggested that tunicamycin may be a potential anti‑cancer agent for colon carcinoma therapy.

Gene expression profile induced by arsenic trioxide in chronic lymphocytic leukemia cells reveals a central role for heme oxygenase-1 in apoptosis and regulation of matrix metalloproteinase-9

CLL remains an incurable disease in spite of the many new compounds being tested. Arsenic trioxide (ATO) induces apoptosis in all CLL cell types and could constitute an efficient therapy. To further explore this, we have studied the gene expression profile induced by ATO in CLL cells. ATO modulated many genes, largely involved in oxidative stress, being HMOX1 the most upregulated gene, also induced at the protein level. ATO also increased MMP-9, as we previously observed, both at the mRNA and protein level. Using specific inhibitors, qPCR analyses, and gene silencing approaches we demonstrate that upregulation of MMP-9 by ATO involved activation of the p38 MAPK/AP-1 signaling pathway. Moreover, gene silencing HMOX1 or inhibiting HMOX1 activity enhanced p38 MAPK phosphorylation and c-jun expression/activation, resulting in transcriptional upregulation of MMP-9. Overexpression of HMOX1 or enhancement of its activity, had the opposite effect. Cell viability analyses upon modulation of HMOX1 expression or activity demonstrated that HMOX1 had a pro-apoptotic role and enhanced the cytotoxic effect of ATO in CLL cells. We have therefore identified a new mechanism in which HMOX1 plays a central role in the response of CLL cells to ATO and in the regulation of the anti-apoptotic protein MMP-9. Thus, HMOX1 arises as a new therapeutic target in CLL and the combination of HMOX1 modulators with ATO may constitute an efficient therapeutic strategy in CLL.

O-linked N-acetylglucosamine transferase enhances secretory clusterin expression via liver X receptors and sterol response element binding protein regulation in cervical cancer

O-linked N-acetylglucosamine transferase (OGT) expression is increased in various cancer types, indicating the potential importance of O-GlcNAcylation in tumorigenesis. Secretory clusterin (sCLU) is involved in cancer cell proliferation and drug resistance, and recently, liver X receptors (LXRs) and sterol response element binding protein-1 (SREBP-1) were reported to regulate sCLU transcription. Here, we found that sCLU is significantly increased in cervical cancer cell lines, which have higher expression levels of O-GlcNAc and OGT than keratinocytes. OGT knockdown decreased expression of LXRs, SREBP-1 and sCLU through hypo-O-GlcNAcylation of LXRs. Additionally, treatment with Thiamet G, O-GlcNAcase OGA inhibitor, increased expression of O-GlcNAcylation and sCLU, and high glucose increased levels of LXRs, SREBP-1 and sCLU in HeLa cells. Moreover, OGT knockdown induced G₀/G₁ phase cell cycle arrest and late apoptosis in cisplatin-treated HeLa cells, and decreased viability compared to OGT intact HeLa cells. Taken together, these findings suggest that OGT, O-GlcNAcylated LXRs, and SREBP-1 increase sCLU expression in cervical cancer cells, which contributes to drug resistance.

ADAMTS1-mediated targeting of TSP-1 by PPARδ suppresses migration and invasion of breast cancer cells

Migration and invasion of cancer cells into surrounding tissue is a key stage of cancer metastasis. Here, we show that peroxisome proliferator-activated receptor (PPAR) δ regulates migration and invasion of human breast cancer cells via thrombospondin-1 (TSP-1) and its degrading protease, a disintegrin and metalloprotease domains with thrombospondin motifs 1 (ADAMTS1). Activation of PPARδ by GW501516, a specific ligand for PPARδ, led to marked inhibition in the cell migration and TSP-1 expression of breast cancer. These effects were suppressed by small interfering RNA-mediated knock-down of ADAMTS1, indicating that ADAMTS1 is involved in PPARδ-mediated inhibition of migration and TSP-1 expression in breast cancer cells. In addition, ligand-activated PPARδ upregulated expression of ADAMTS1 at the transcriptional level via binding of PPARδ to a direct repeat-1 site within the ADAMTS1 gene promoter. Furthermore, ligand-activated PPARδ suppressed invasion of breast cancer cells in an ADAMTS1-dependent manner. Taken together, these results demonstrate that PPARδ suppresses migration and invasion of breast cancer cells by downregulating TSP-1 in a process mediated by upregulation of ADAMTS1.

Clusterin and neuropilin-2 as potential biomarkers of tumor progression in benzo[a]pyrene-transformed 16HBE cells xenografted nude mouse model

Benzo[a]pyrene (BaP) is a ubiquitous environment contaminant and its exposure could increase incidence of human lung cancer. In order to confirm and compare potential biomarkers of BaP-induce carcinogenesis and tumor progression, time-dependent changes of clusterin (CLU) and neuropilin-2 (NRP2) levels were evaluated in sera of BaP-transformed 16HBE cell line T-16HBE-C1 cells xenografted nude mice. Performance of CLU and NRP2 on tissue classification and tumor progression forecast was also calculated. Levels of CLU and NRP2 were significant elevated in both culture supernatant of T-16HBE-C1 cells and sera of T-16HBE-C1 cells xenografted nude mice compared with control. CLU and NRP2 were both found positively stained in tumor tissue. CLU and NRP2 alone could well predicate tumor progression in nude mice and CLU appeared to be more sensitive than NRP2. When both of them combined, performance of predication would improve. In conclusion, CLU and NRP2 could serve as potential biomarkers of tumor progression in nude mice xenografted with T-16HBE-C1 cells.

Patterns and functional implications of platelets upon tumor "education"

While platelets are traditionally recognized to play a predominant role in hemostasis and thrombosis, increasing evidence verifies its involvement in malignancies. As a component of the tumor microenvironment, platelets influence carcinogenesis, tumor metastasis and chemotherapy efficiency. Platelets status is thus predictable as a hematological biomarker of cancer prognosis and a hot target for therapeutic intervention. On the other hand, the role of circulating tumor cells (CTCs) as an inducer of platelet activation and aggregation has been well acknowledged. The cross-talk between platelets and CTCs is reciprocal on that the CTCs activate platelets while platelets contribute to CTCs' survival and dissemination. This review covers some of the current issues related to the loop between platelets and tumor aggression, including the manners of tumor cells in "educating" platelets and biofunctional alterations of platelets upon tumor "education". We also highlight the potential clinical applications on the interplay between tumors and platelets. Further studies with well-designed prospective multicenter trials may contribute to clinical "liquid biopsy" diagnosis by evaluating the global changes of platelets.