High expression levels of Cyr61 and VEGF are associated with poor prognosis in osteosarcoma

Hypoxia-associated markers in the prognosis of oral canine melanoma

Canine oral malignant melanoma (COMM) is the most common neoplasm in the oral cavity characterized by local invasiveness and high metastatic potential. Hypoxia represents a crucial feature of the solid tumor microenvironment promoting cancer progression and drug resistance. Hypoxia-inducible factor-1α (HIF-1α) and its downstream effectors, vascular endothelial growth factor A (VEGF-A), glucose transporter isoform 1 (GLUT1), C-X-C chemokine receptor type 4 (CXCR4), and carbonic anhydrase IX (CAIX), are the main regulators of the adaptive response to low oxygen availability. The prognostic value of these markers was evaluated in 36 COMMs using immunohistochemistry. In addition, the effects of cobalt chloride-mediated hypoxia were evaluated in 1 primary COMM cell line. HIF-1α expression was observed in the nucleus, and this localization correlated with the presence or enhanced expression of HIF-1α-regulated genes at the protein level. Multivariate analysis revealed that in dogs given chondroitin sulfate proteoglycan-4 (CSPG4) DNA vaccine, COMMs expressing HIF-1α, VEGF-A, and CXCR4 were associated with shorter disease-free intervals (DFI) compared with tumors that were negative for these markers (P = .03), suggesting hypoxia can influence immunotherapy response. Western blotting showed that, under chemically induced hypoxia, COMM cells accumulate HIF-1α and smaller amounts of CAIX. HIF-1α induction and stabilization triggered by hypoxia was corroborated by immunofluorescence, showing its nuclear translocation. These findings reinforce the role of an hypoxic microenvironment in tumor progression and patient outcome in COMM, as previously established in several human and canine cancers. In addition, hypoxic markers may represent promising prognostic markers, highlighting opportunities for their use in therapeutic strategies for COMMs.

The correlation between clinical outcomes and genomic analysis with high risk factors for the progression of osteosarcoma

Osteosarcoma (OS) is a rare but aggressive malignancy. Despite previous reports, molecular characterization of this disease is not well understood, and little is known regarding OS in Chinese patients. Herein, we analyzed the genomic signatures of 73 Chinese OS cases. TP53, NCOR1, LRP1B, ATRX, RB1, and TFE3 were the most frequently mutated gene in our OS cohort. In addition, the genomic analysis of Western OS patients was performed. Notably, there were remarkable disparities in mutational landscape, base substitution pattern, and tumor mutational burden between the Chinese and Western OS cohorts. Specific molecular mechanisms, including DNA damage repair (DDR) gene mutations, copy number variation (CNV) presence, aneuploidy, and intratumoral heterogeneity, were associated with disease progression. Additionally, 30.1% of OS patients carried clinically actionable alterations, which were mainly enriched in PI3K, MAPK, DDR, and RTK signaling pathways. A specific molecular subtype incorporating DDR alterations and CNVs was significantly correlated with distant metastasis-free survival and event-free survival, and this correlation was observed in all subgroups with different characteristics. These findings comprehensively elucidated the genomic profile and revealed novel prognostic factors in OS, which would contribute to understanding this disease and promoting precision medicine of this population.

CircUSP48 promotes malignant behavior by regulating CYR61 via miR-365 in osteosarcoma

Even though circular RNAs (circRNAs), a class of non-coding endogenous RNA, play a crucial role in the progression of osteosarcoma (OS), the specific function of hsa_circ_0000028 (circUSP48) remains unclear. This study aims to elucidate the mechanism by which circUSP48 regulates OS. We employed qRT-PCR and western blot techniques to quantify circDOCK1, miR-186, and DNMT3A levels. Cell proliferation was assessed using the cell counting kit-8 (CCK-8), 5-Ethynyl-20-deoxyuridine (EdU) assay, and colony formation assay. Cell migration and invasion were evaluated through Transwell and cell scratch assays. Furthermore, we performed dual-luciferase reporter, RIP, and RNA pull-down assays to investigate the association between circUSP48, miR-365, and CYR61. In addition, an in vivo xenograft model was utilized to assess the functional role of circUSP48. High levels of circUSP48 and CYR61 were observed in OS tissues and cells, while miR-365 levels were low. Knockdown of circUSP48 suppressed the multiplication, motility, and invasion of OS cells, thereby reducing carcinoma growth. Moreover, inhibition of miR-365 reversed the OS cell-suppressive effect caused by circUSP48 knockdown through direct interaction with circUSP48. Additionally, circUSP48 upregulated the expression of CYR61 by sponging miR-365. The findings suggest that circUSP48 promotes malignant behavior in OS by regulating the expression of CYR61 through miR-365, making it a potential therapeutic target for OS.

Cross-sectional and longitudinal associations of serum Cysteine-rich 61 with severity and prognosis among community-acquired pneumonia patients in China

Background

Cysteine-rich 61 (CYR61) is implicated in many pulmonary diseases. However, the relationship between CYR61 and community-acquired pneumonia (CAP) patients was unknown. This research aimed to estimate the correlations of serum CYR61 with severity and prognosis in CAP patients through a prospective cohort study.

Methods

All 541 CAP patients were enrolled in this study. Fasting venous blood was collected. Clinical characteristics and demographic information were obtained. CYR61 and inflammatory cytokines were detected in serum using ELISA.

Results

Serum CYR61 was gradually increased in parallel with severity scores in CAP patients. Correlative analysis indicated that serum CYR61 was strongly associated with many clinical parameters in CAP patients. Moreover, mixed logistic and linear regression models found that there were positive correlations between serum CYR61 and CAP severity scores after adjusted for age, BMI, and respiratory rate. Stratified analyses suggested that age affected the associations between serum CYR61 and severity scores. On admission, higher serum CYR61 levels elevated the risks of mechanical ventilation, vasoactive agent, ICU admission, death, and longer hospital stays during hospitalization. Moreover, serum CYR61 in combination with severity scores upregulated the predictive capacities for severity and death than single serum CYR61 or severity scores in CAP patients.

Conclusion

There are significantly positive dose-response associations of serum CYR61 on admission with the severity and adverse prognostic outcomes, demonstrating that CYR61 is involved in the pathophysiology of CAP. Serum CYR61 may be used as a potential biomarker for the diagnosis and prognosis in CAP patients.

Correlation of vascular endothelial growth factor with survival and pathological characteristics of patients with osteosarcoma: A systematic review and meta-analysis

OBJECTIVE

This study aimed to assess the prognostic role of vascular endothelial growth factor (VEGF) expression in osteosarcoma.

METHODS

Systematic searches of PubMed, Embase, CINAHL, Cochrane Library, ScienceDirect, and Web of Science were conducted. The correlation between VEGF expression and patients' survival was our primary endpoint. The secondary endpoints were the associations between VEGF level and patients' sociodemographic and pathological characteristics. The pooled hazard ratio (HR) or odd ratio (OR) and corresponding 95% confidence intervals (CIs) were obtained to assess the associations between VEGF expression and the target factors. Subgroup and meta-regression analyses were conducted to explore potential factors that associated with VEGF efficacy.

RESULTS

The combined HR suggested that a positive VEGF status has a negative impact on overall survival (OS) (HR = 2.58; 95% CI, 2.09-3.19; P < 0.0001) and disease-free survival (DFS) (HR = 2.54; 95% CI, 1.84-3.50; P < 0.0001) in patients with osteosarcoma. Meta-regression analysis ruled out the influence of cut-off value, disease stage, histological subtype, disease grade, tumour location, geographic area, publication year, and method of HR acquisition on heterogeneity. Results showed that VEGF expression was closely correlated with tumour staging, chemotherapy response, and metastasis.

CONCLUSION

Based on the study results, VEGF could serve as an effective biomarker of prognosis in patients with osteosarcoma. Besides, VEGF was related to increased tumour malignancy, which might help guide clinical decision-making regarding therapy and outcomes.

Targeted Delivery of Chemotherapeutic Agents for Osteosarcoma Treatment

Since osteosarcoma (OS) is an aggressive bone cancer with unknown molecular pathways of etiology and pathophysiology, improving patient survival has long been a challenge. The conventional therapy is a complex multidisciplinary management that include radiotherapy, chemotherapy which followed by surgery and then post-operative adjuvant chemotherapy. However, they have severe side effects because the majority of the medicines used have just a minor selectivity for malignant tissue. As a result, treating tumor cells specifically without damaging healthy tissue is currently a primary goal in OS therapy. The coupling of chemotherapeutic drugs with targeting ligands is a unique therapy method for OS that, by active targeting, can overcome the aforementioned hurdles. This review focuses on advances in ligands and chemotherapeutic agents employed in targeted delivery to improve the capacity of active targeting and provide some insight into future therapeutic research for OS.

The role of vascular endothelial growth factor as a prognostic and clinicopathological marker in osteosarcoma: a systematic review and meta-analysis

BACKGROUND

In recent years, numerous investigations have been conducted to determine the clinical significance and critical functions of vascular endothelial growth factor (VEGF) in various malignant cancers. The purpose of this meta-analysis was to comprehensively evaluate the prognostic and clinicopathological value of VEGF in patients with osteosarcoma.

METHODS

We performed a systematic literature retrieval of available databases. Odds ratios (ORs) or standard mean difference (SMD) for clinicopathological parameters, hazard ratios (HRs) for overall survival and disease-free survival were calculated to assess the correlation between VEGF expression and prognosis in patients with osteosarcoma.

RESULTS

A total of 22 studies with 1144 patients were included in our study. Pooled analyses showed that VEGF overexpression predicted worse overall survival (HR, 2.42; 95% CI, 1.87-3.11, p < 0.001) and disease-free survival (HR, 2.604; 95% CI, 1.698-3.995, p < 0.001), respectively. Furthermore, investigation regarding osteosarcoma clinicopathologic characteristics suggested that high VEGF expression was significantly associated with metastasis (OR, 4.39; 95% CI, 2.77-6.95; p < 0.001), clinical stage (OR, 0.73; 95% CI, 0.62-0.87; p < 0.001), and microvessel density (SMD, 3.33, 95% CI,1.57-5.10, p < 0.001), but not associated with tumor location, gender, age, local recurrence, and chemotherapy response.

CONCLUSION

Our meta-analysis findings suggest that elevated VEGF expression may be a predictive biomarker for poor prognosis and adverse clinicopathological characteristics in patients with osteosarcoma.

The roles of metastasis-related proteins in the development of giant cell tumor of bone, osteosarcoma and Ewing's sarcoma

BACKGROUND:

Giant cell tumor of bone (GC), osteosarcoma (OS) and Ewing’s sarcoma (ES) are three different types of bone cancer with common and specific pathology features.

OBJECTIVE:

The purpose of the study was to examine the relationship and differences of the three bone tumors using clinical samples.

METHODS:

Through screening the profiles of clinical samples from GC, OS and ES patients using a humanoncology array, we found 26, 25 and 15 tumorigenesis factors significantly increased in GS, OS and ES tissues compared to normal individuals. eNOS, endostatin, HIF-1α, IL-6, CCL2/MCP-1, CCL8/MCP-2, CCL7/MCP-3, Tie and VEGF directly or indirectly involve in the metastasis Therefore, expression levels of the 6 factors were further determined by Western blot.

RESULTS:

The results showed levels of MCP1, MCP2, MCP3 or IL-6 in the GS, OS and ES significantly increased, and the expression levels of angiogenesis and anti-angiogenesis factors containing eNOS, endostatin, HIF-1α, Tie or VEGF were enhanced.

CONCLUSIONS:

Our results suggest that eNOS, endostatin, HIF-1α, IL-6, CCL2/MCP-1, CCL8/MCP-2, CCL7/MCP-3, Tie and VEGF may play important roles in tumorigenesis, reveal the expression differences of tumor-associated cytokines and angiogenesis related factors, and provide clinical evidence for studying the mechanisms on the metastasis in GC, OS and ES.

CCN proteins in the musculoskeletal system: current understanding and challenges in physiology and pathology

The acronym for the CCN family was recently revised to represent “cellular communication network”. These six, small, cysteine-enriched and evolutionarily conserved proteins are secreted matricellular proteins, that convey and modulate intercellular communication by interacting with structural proteins, signalling factors and cell surface receptors. Their role in the development and physiology of musculoskeletal system, constituted by connective tissues where cells are interspersed in the cellular matrix, has been broadly studied. Previous research has highlighted a crucial balance of CCN proteins in mesenchymal stem cell commitment and a pivotal role for CCN1, CCN2 and their alter ego CCN3 in chondrogenesis and osteogenesis; CCN4 plays a minor role and the role of CCN5 and CCN6 is still unclear. CCN proteins also participate in osteoclastogenesis and myogenesis. In adult life, CCN proteins serve as mechanosensory proteins in the musculoskeletal system providing a steady response to environmental stimuli and participating in fracture healing. Substantial evidence also supports the involvement of CCN proteins in inflammatory pathologies, such as osteoarthritis and rheumatoid arthritis, as well as in cancers affecting the musculoskeletal system and bone metastasis. These matricellular proteins indeed show involvement in inflammation and cancer, thus representing intriguing therapeutic targets. This review discusses the current understanding of CCN proteins in the musculoskeletal system as well as the controversies and challenges associated with their multiple and complex roles, and it aims to link the dispersed knowledge in an effort to stimulate and guide readers to an area that the writers consider to have significant impact and relevant potentialities.

Serum CYR61 as a potential biomarker for the diagnosis of esophagogastric junction tumor

BACKGROUND

Esophagogastric junction tumor (EGJ) is a rare but fatal disease with a rapid rising incidence worldwide in the late 20 years, and it lacks a convenient and safe method for diagnosis. The present study aimed to evaluate the potential of serum CYR61 as a biomarker for the diagnosis of EGJ tumor.

METHODS

Enzyme-linked immunosorbent assay (ELISA) was used to estimate CYR61 levels in sera of 152 EGJ tumor patients and 137 normal controls. Receiver operating characteristics (ROC) was carried out to evaluate the diagnostic accuracy. The Mann-Whitney's U test was used to compare the difference of serum levels of CYR61 between groups. And chi-square tests were employed to estimate the correlation of the positive rate of serum CYR61 between/among subgroups.

RESULTS

Serum CYR61 levels were statistically lower in EGJ tumor and early-stage EGJ tumor patients than those in normal controls (P<0.0001). The sensitivity, specificity and the area under the curve (AUC) of this biomarker in EGJ tumor were 88.2%, 43.8% and 0.691, respectively, and those for early stage of EGJ tumor were 80.0%, 66.4% and 0.722, respectively. Analyses showed that there was no correlation between the clinical data and the levels of CYR61 (P>0.05).

CONCLUSION

The present study showed that CYR61 might be a potential biomarker to assist the diagnosis of EGJ tumor.

Hot and Cold Tumors: Is Endoglin (CD105) a Potential Target for Vessel Normalization?

Tumors are complex masses formed by malignant but also by normal cells. The interaction between these cells via cytokines, chemokines, growth factors, and enzymes that remodel the extracellular matrix (ECM) constitutes the tumor microenvironment (TME). This TME can be determinant in the prognosis and the response to some treatments such as immunotherapy. Depending on their TME, two types of tumors can be defined: hot tumors, characterized by an immunosupportive TME and a good response to immunotherapy; and cold tumors, which respond poorly to this therapy and are characterized by an immunosuppressive TME. A therapeutic strategy that has been shown to be useful for the conversion of cold tumors into hot tumors is vascular normalization. In this review we propose that endoglin (CD105) may be a useful target of this strategy since it is involved in the three main processes involved in the generation of the TME: angiogenesis, inflammation, and cancer-associated fibroblast (CAF) accumulation. Moreover, the analysis of endoglin expression in tumors, which is already used in the clinic to study the microvascular density and that is associated with worse prognosis, could be used to predict a patient's response to immunotherapy.

Prognostic and Therapeutic Utility of Variably Expressed Cell Surface Receptors in Osteosarcoma

Background

Six cell surface receptors, human epidermal growth factor receptor-2 (Her-2), platelet-derived growth factor receptor-β (PDGFR-β), insulin-like growth factor-1 receptor (IGF-1R), insulin receptor (IR), c-Met, and vascular endothelial growth factor receptor-3 (VEGFR-3), previously demonstrated variable expression across varying patient-derived and standard osteosarcoma (OS) cell lines. The current study sought to validate previous expression patterns and evaluate whether these receptors offer prognostic and/or therapeutic value.

Methods

Patient-derived OS cell lines (n = 52) were labeled with antibodies to Her-2, PDGFR-β, IGF-1R, IR, c-Met, and VEGFR-3. Expression was characterized using flow cytometry. The difference in geometric mean fluorescent intensity (geoMFI_diff = geoMFI_positive - geoMFI_negative) was calculated for each receptor across all cell lines. Receptor expression was categorized as low (Q1), intermediate (Q2, Q3), or high (Q4). The event-free survival (EFS) and overall survival for the six cell surface receptors were estimated by the Kaplan-Meier method. Differences in hazard for EFS event and overall survival event for patients in each of the three expression levels in each of the six cell surface receptors were assessed using the log-rank test.

Results

All 6 receptors were variably expressed in the majority of cell lines. IR and PDGFR-β expressions were found to be significant predictors for EFS amongst patients with nonmetastatic disease (p=0.02 and 0.01, respectively). The hazard ratio for EFS was significantly higher between high IR and intermediate IR expression (HR = 2.66, p=0.02), as well as between high PDGFR-β and intermediate PDGFR-β expression (HR = 5.68, p=0.002). Her-2, c-Met, IGF-1R, and VEGFR-3 were not found to be significant predictors for either EFS or overall survival.

Conclusion

The six cell surface receptors demonstrated variable expression across the majority of patient-derived OS cell lines tested. Limited prognostic value was offered by IR and PDGFR-β expression within nonmetastatic patients. The remaining receptors do not provide clear prognostic utility. Nevertheless, their consistent, albeit variable, surface expression across a large panel of patient-derived OS cell lines maintains their potential use as future therapeutic targets.

Novel application of single-cell next-generation sequencing for determination of intratumoral heterogeneity of canine osteosarcoma cell lines

Osteosarcoma (OSA) is a highly aggressive and metastatic neoplasm of both the canine and human patient and is the leading form of osseous neoplasia in both species worldwide. To gain deeper insight into the heterogeneous and genetically chaotic nature of OSA, we applied single-cell transcriptome (scRNA-seq) analysis to 4 canine OSA cell lines. This novel application of scRNA-seq technology to the canine genome required uploading the CanFam3.1 reference genome into an analysis pipeline (10X Genomics Cell Ranger); this methodology has not been reported previously in the canine species, to our knowledge. The scRNA-seq outputs were validated by comparing them to cDNA expression from reverse-transcription PCR (RT-PCR) and Sanger sequencing bulk analysis of 4 canine OSA cell lines (COS31, DOUG, POS, and HMPOS) for 11 genes implicated in the pathogenesis of canine OSA. The scRNA-seq outputs revealed the significant heterogeneity of gene transcription expression patterns within the cell lines investigated (COS31 and DOUG). The scRNA-seq data showed 10 distinct clusters of similarly shared transcriptomic expression patterns in COS31; 12 clusters were identified in DOUG. In addition, cRNA-seq analysis provided data for integration into the Qiagen Ingenuity Pathway Analysis software for canonical pathway analysis. Of the 81 distinct pathways identified within the clusters, 33 had been implicated in the pathogenesis of OSA, of which 18 had not been reported previously in canine OSA.

Use of Antiangiogenic Therapies in Pediatric Solid Tumors

Cancer is an important cause of death in childhood. In recent years, scientists have made an important effort to achieve greater precision and more personalized treatments against cancer. But since only a few pediatric patients have identifiable therapeutic targets, other ways to stop the neoplastic cell proliferation and dissemination are needed. Therefore, the inhibition of general processes involved in the growth and behavior of tumors can be a relevant strategy for the development of new cancer therapies. In the case of solid tumors, one of these processes is angiogenesis, essential for tumor growth and generation of metastases. This review summarizes the results obtained with the use of antiangiogenic drugs in the main pediatric malignant solid tumors and also an overview of clinical trials currently underway. It should be noted that due to the rarity and heterogeneity of the different types of pediatric cancer, most studies on antiangiogenic drugs include only a small number of patients or isolated clinical cases, so they are not conclusive and further studies are needed.

Clinical significance and in vitro cellular regulation of hypoxia mimicry on HIF-1α and downstream genes in canine appendicular osteosarcoma

Cellular adaptation to a hypoxic microenvironment is essential for tumour progression and is largely mediated by HIF-1α and hypoxia-regulated factors, including CXCR4, VEGF-A and GLUT-1. In human osteosarcoma, hypoxia is associated with resistance to chemotherapy as well as with metastasis and poor survival, whereas little is known about its role in canine osteosarcoma (cOSA). This study aimed primarily to evaluate the prognostic value of several known hypoxic markers in cOSA. Immunohistochemical analysis for HIF-1α, CXCR4, VEGF-A and GLUT-1 was performed on 56 appendicular OSA samples; correlations with clinicopathological features and outcome was investigated. The second aim was to investigate the in vitro regulation of markers under chemically induced hypoxia (CoCl₂). Two primary canine osteosarcoma cell lines were selected, and Western blotting, immunofluorescence and qRT-PCR were used to study protein and gene expression. Dogs with high-grade OSA (35.7%) were more susceptible to the development of metastases (P = 0.047) and showed high HIF-1α protein expression (P = 0.007). Moreover, HIF-1α overexpression (56%) was correlated with a shorter disease-free interval (DFI; P = 0.01), indicating that it is a reliable negative prognostic marker. The in vitro experiments identified an accumulation of HIF-1α in cOSA cells after chemically induced hypoxia, leading to a significant increase in GLUT-1 transcript (P = 0.02). HIF-1α might be a promising prognostic marker, highlighting opportunities for the use of therapeutic strategies targeting the hypoxic microenvironment in cOSA. These results reinforce the role of the dog as a comparative animal model since similar hypoxic mechanisms are reported in human osteosarcoma.

LAIR-1 overexpression inhibits epithelial-mesenchymal transition in osteosarcoma via GLUT1-related energy metabolism

Background

Leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is a collagen receptor belonging to the immunoglobulin superfamily. Although previous studies have evaluated the biological role of LAIR in solid tumors, the precise mechanisms underlying the functions of LAIR-1 as a regulator of tumor biological functions remain unclear.

Methods

LAIR-1 expression was evaluated by immunohistochemical analysis using an osteosarcoma (OS) tissue microarray. Wound healing and transwell migration assays were performed to evaluate tumor cell migration. Quantitative real-time polymerase chain reaction (qPCR) and western blotting were conducted to detect the expression of epithelial–mesenchymal transition (EMT)-related molecules. RNA-sequencing (RNA-seq) was conducted to evaluate the mRNA expression profiles after overexpressing LAIR-1 in OS cells. Glucose transporter (Glut)1 expression in OS cells was evaluated by western blotting.

Results

LAIR-1 expression was significantly different between the T1 and T2 stages of OS tumors, and it inhibited OS cell migration. LAIR-1 expression was inversely correlated with the expression of Twist1, an EMT-associated transcription factor, via the Forkhead box O1 signal transduction pathway. Furthermore, RNA-seq and qPCR demonstrated that the expression of EMT energy metabolism-related molecules was significantly reduced after LAIR-1 overexpression.

Conclusions

LAIR-1 overexpression decreased the expression of Glut1 and inhibited the expression of EMT-related molecules in OS cells. These findings provide new insights into the molecular mechanism underlying OS progression.

Modeling the Tumor Microenvironment and Pathogenic Signaling in Bone Sarcoma

Investigations of cancer biology and screening of potential therapeutics for efficacy and safety begin in the preclinical laboratory setting. A staple of most basic research in cancer involves the use of tissue culture plates, on which immortalized cell lines are grown in monolayers. However, this practice has been in use for over six decades and does not account for vital elements of the tumor microenvironment that are thought to aid in initiation, propagation, and ultimately, metastasis of cancer. Furthermore, information gleaned from these techniques does not always translate to animal models or, more crucially, clinical trials in cancer patients. Osteosarcoma (OS) and Ewing sarcoma (ES) are the most common primary tumors of bone, but outcomes for patients with metastatic or recurrent disease have stagnated in recent decades. The unique elements of the bone tumor microenvironment have been shown to play critical roles in the pathogenesis of these tumors and thus should be incorporated in the preclinical models of these diseases. In recent years, the field of tissue engineering has leveraged techniques used in designing scaffolds for regenerative medicine to engineer preclinical tumor models that incorporate spatiotemporal control of physical and biological elements. We herein review the clinical aspects of OS and ES, critical elements present in the sarcoma microenvironment, and engineering approaches to model the bone tumor microenvironment. Impact statement The current paradigm of cancer biology investigation and therapeutic testing relies heavily on monolayer, monoculture methods developed over half a century ago. However, these methods often lack essential hallmarks of the cancer microenvironment that contribute to tumor pathogenesis. Tissue engineers incorporate scaffolds, mechanical forces, cells, and bioactive signals into biological environments to drive cell phenotype. Investigators of bone sarcomas, aggressive tumors that often rob patients of decades of life, have begun to use tissue engineering techniques to devise in vitro models for these diseases. Their efforts highlight how critical elements of the cancer microenvironment directly affect tumor signaling and pathogenesis.

The anti-neoplastic effect of doxycycline in osteosarcoma as a metalloproteinase (MMP) inhibitor: a systematic review

Background

Osteosarcoma is a very aggressive primary bone tumour, affecting mainly young populations. Most cases diagnosed have distant macro- and micro-metastases at the time of diagnosis. Surgical resection with neoadjuvant and adjuvant therapies improves the overall and disease-free survival of patients. Doxycycline, a synthetic tetracycline, has been found to act either as an antibiotic drug or as a chemotherapeutic agent. Its anti-neoplastic role has been found to be significant, in vitro and in vivo laboratory trials, in various types of cancer, such as prostate, intestinal, central neural system cancers and osteosarcoma. Inhibition of metalloproteinases (MMPs) in different stages of tumour expansion is the most well-understood mechanism. MMPs are secreted molecules from various normal cells, such as fibroblasts, leucocytes and vascular smooth muscles, as well as from cells with high proliferative potential, such as tumour cells. In osteosarcoma, MMPs have been found to be overexpressed. MMPs help osteosarcoma cells survive, grow and produce metastases in distant sites, mainly in the lungs. Doxycycline blocks extracellular matrix and basic membrane degradation by suppressing MMP function. As a consequence, osteosarcoma cells lose their ability to invade and metastasize. Additionally, doxycycline eliminates the secretion of vascular endothelial growth factor (VEGF) and deprives the supply of circulating nutrients by its anti-angiogenesis action. The aim of this review is to evaluate doxycycline’s action against osteosarcoma cells as an MMP-inhibitor and interpret its usage as a chemotherapeutic agent.

Methods

We checked PubMed and Google Scholar for recently published data, on the tumour-supportive role of MMPs and VEGF in osteosarcoma cells. We further studied published experimental trials on the role of doxycycline as a tumour-suppressive agent via MMPs and VEGF inhibition.

Results

MMPs and VEGF have been found to play a fundamental role in osteosarcoma cells survival and high aggressiveness by in vitro, in vivo and clinical trials. Nevertheless, doxycycline has proved its tumour-suppressive effect by in vivo experimental trials in various cancers but not yet in osteosarcoma.

Conclusion

Doxycycline remains a promising chemotherapeutic agent against osteosarcoma via MMP inhibition, showing the need for further in vivo and clinical trials to be carried out in the future.

Surface engineering of nanoparticles with ligands for targeted delivery to osteosarcoma

Osteosarcoma is one of the most common malignant bone tumors which affect adolescents. Neoadjuvant chemotherapy followed by operation has become recommended for osteosarcoma treatment. Whereas, the effects of conventional chemotherapy are unsatisfactory because of multidrug resistance, fast clearance rate, nontargeted delivery, side effects and so on. Accordingly, Nanoparticle-mediated targeted drug delivery system (NTDDS) is recommended to be a novel treatment strategy for osteosarcoma. NTDDS can overcome the above obstacles by enhanced permeability and retention effect and active targeting. The active targeting of the delivery system is mainly based on ligands. In this study, we investigate and summarize the most common ligands used in the latest NTDDS for osteosarcoma. It might provide new insights into nanomedicine for osteosarcoma treatment.

Nanomedicine in osteosarcoma therapy: Micelleplexes for delivery of nucleic acids and drugs toward osteosarcoma-targeted therapies

Osteosarcoma(OS) represents the main cancer affecting bone tissue, and one of the most frequent in children. In this review we discuss the major pathological hallmarks of this pathology, its current therapeutics, new active biomolecules, as well as the nanotechnology outbreak applied to the development of innovative strategies for selective OS targeting. Small RNA molecules play a role as key-regulator molecules capable of orchestrate different responses in what concerns cancer initiation, proliferation, migration and invasiveness. Frequently associated with lung metastasis, new strategies are urgent to upgrade the therapeutic outcomes and the life-expectancy prospects. Hence, the prominent rise of micelleplexes as multifaceted and efficient structures for nucleic acid delivery and selective drug targeting is revisited here with special emphasis on ligand-mediated active targeting. Future landmarks toward the development of novel nanostrategies for both OS diagnosis and OS therapy improvements are also discussed.

[Angiotensin Ⅱ induces apoptosis of HEK293T cells by up-regulating Cyr61 expression]

OBJECTIVE

To investigate the role of Cyr61 in angiotensin Ⅱ (AngⅡ)-induced functional changes in HEK293 cells and explore the mechanism.

METHODS

Cyr61 knockdown in cultured HEK293T cells was achieved by transfection of the cells with CRISPR/Cas9 KO plasmid. The changes in apoptosis and expression levels of Cyr61 and Bcl-2 in the cells with or without Cyr61 knockdown in response to treatment with 10^-7 mol/L AngⅡ for 48 h were analyzed using flow cytometry, qRT-PCR and Western blotting.

RESULTS

The cells with Cyr61 knockdown showed significantly decreased expression of Cyr61 protein as compared with the control cells (P &lt; 0.05). AngⅡ treatment for 48 h significantly increased the expression of Cyr61 and lowers the expression of Bcl-2 at both the protein and mRNA levels in HEK293T cells. In HEK293T cells with Cyr61 knockdown, AngⅡ treatment resulted in significantly increased expression of Bcl-2 in HEK293T cells as compared with that of the control group (P &lt; 0.05). AngⅡ treatment caused significantly increased apoptotic rate in HEK293T cells as compared with the cells with Cyr61 knockdown [(26.94 ± 3.73)% vs (3.87 ± 0.83)%, P &lt; 0.05), and the apoptosis rate was significantly lowered to (15.76 ± 1.31)% in HEK293T cells with Cyr61 knockdown following AngⅡ treatment (P &lt; 0.05).

CONCLUSIONS

The up-regulation of Cyr61 expression is related with AngⅡ-induced injury in HEK293T cells, and down-regulating Cyr61 expression can effectively protect HEK293T cells against AngⅡ-induced injury.

Extracellular Nanovesicles Secreted by Human Osteosarcoma Cells Promote Angiogenesis

Angiogenesis involves a number of different players among which extracellular nanovesicles (EVs) have recently been proposed as an efficient cargo of pro-angiogenic mediators. Angiogenesis plays a key role in osteosarcoma (OS) development and progression. Acidity is a hallmark of malignancy in a variety of cancers, including sarcomas, as a result of an increased energetic metabolism. The aim of this study was to investigate the role of EVs derived from osteosarcoma cells on angiogenesis and whether extracellular acidity, generated by tumor metabolism, could influence EVs activity. For this purpose, we purified and characterized EVs from OS cells maintained at either acidic or neutral pH. The ability of EVs to induce angiogenesis was assessed in vitro by endothelial cell tube formation and in vivo using chicken chorioallantoic membrane. Our findings demonstrated that EVs derived from osteosarcoma cells maintained either in acidic or neutral conditions induced angiogenesis. The results showed that miRNA and protein content of EVs cargo are correlated with pro-angiogenic activity and this activity is increased by the acidity of tumor microenvironment. This study provides evidence that EVs released by human osteosarcoma cells act as carriers of active angiogenic stimuli that are able to promote endothelial cell functions relevant to angiogenesis.

Identification of the Transcriptional Networks and the Involvement in Angiotensin II-Induced Injury after CRISPR/Cas9-Mediated Knockdown of Cyr61 in HEK293T Cells

Background

The transcriptional networks of Cyr61 and its function in cell injury are poorly understood. The present study depicted the lncRNA and mRNA profiles and the involvement in angiotensin II-induced injury after Cyr61 knockdown mediated by CRISPR/Cas9 in HEK293T cells.

Methods

HEK293T cells were cultured, and Cyr61 knockdown was achieved by transfection of the CRISPR/Cas9 KO plasmid. lncRNA and mRNA microarrays were used to identify differentially expressed genes (DEGs). Gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to determine biofunctions and signaling pathways. RT-PCR was used to validate the microarray results. Cells were divided into four groups: control, Cyr61 knockdown, angiotensin II (Ang II) without Cyr61 knockdown, and Ang II with Cyr61 knockdown. CCK8, western blotting, and flow cytometry analysis were carried out to dissect cellular function.

Results

A total of 23184 lncRNAs and 28264 mRNAs were normalized. 26 lncRNAs and 212 mRNAs were upregulated, and 74 lncRNAs and 233 mRNAs were downregulated after Cyr61 knockdown. Analysis of cellular components, molecular functions, biological processes, and regulatory pathways associated with the differentially expressed mRNAs revealed downstream mechanisms of the Cyr61 gene. The differentially expressed genes were affected for small cell lung cancer, axon guidance, Fc gamma R-mediated phagocytosis, MAPK signaling pathway, focal adhesion, insulin resistance, and metabolic pathways. In addition, Cyr61 expression was increased in accordance with induction of cell cycle arrest and apoptosis and inhibition of cell proliferation induced by Ang II. Knockdown of Cyr61 in HEK293T cells promoted cell cycle procession, decreased apoptosis, and promoted cell proliferation.

Conclusions

The Cyr61 gene is involved in Ang II-induced injury in HEK293T cells. Functional mechanisms of the differentially expressed lncRNAs and mRNAs as well as identification of metabolic pathways will provide new therapeutic targets for Cyr61-realated diseases.

Proliferation inhibition and apoptosis promotion by dual silencing of VEGF and Survivin in human osteosarcoma

Simultaneous silencing of multiple upregulated genes is an attractive and viable treatment strategy for many incurable diseases including cancer. Herein we used a dual gene-targeted siRNA conjugate composed of VEGF and Survivin siRNA sequences in the same backbone to inhibit proliferation and angiogenesis in two human osteosarcoma cell lines. We synthesized siRNA sequences targeting the VEGF and Survivin genes individually (VEGF siRNA and Survivin siRNA) or simultaneously (one-chain-double-target siRNA: dual siRNA). VEGF and Survivin mRNA and protein expression levels in human osteosarcoma MG-63 and Saos-2 cells were detected by qRT-PCR and western blot analysis. VEGF and Survivin protein location and expression were evaluated by immunohistochemistry and immunofluorescence staining. MG-63 and Saos-2 cell migration, proliferation, apoptosis, and angiogenesis were detected by scratch test, MTT assay, flow cytometry, and capillary tube assay respectively. The dual siRNA induced similar downregulation of VEGF and Survivin mRNA and protein levels, compared with VEGF siRNA or Survivin siRNA alone. The dual siRNA caused greater suppression of MG-63 and Saos-2 cell migration, proliferation and angiogenesis, and promoted more cell apoptosis than VEGF siRNA or Survivin siRNA alone, suggesting that the effects of the dual siRNA on inhibiting cell proliferation, migration, and angiogenesis and promoting apoptosis were superior to those of the single-target siRNAs. Simultaneous silencing of VEGF and Survivin using the dual siRNA may be an advantageous alternative for the development of therapeutic strategies against human osteosarcoma.

Oncogenic role of SFRP2 in p53-mutant osteosarcoma development via autocrine and paracrine mechanism

Osteosarcoma (OS), the most common primary bone tumor, is highly metastatic with high chemotherapeutic resistance and poor survival rates. Using induced pluripotent stem cells (iPSCs) generated from Li-Fraumeni syndrome (LFS) patients, we investigate an oncogenic role of secreted frizzled-related protein 2 (SFRP2) in p53 mutation-associated OS development. Interestingly, we find that high SFRP2 expression in OS patient samples correlates with poor survival. Systems-level analyses identified that expression of SFRP2 increases during LFS OS development and can induce angiogenesis. Ectopic SFRP2 overexpression in normal osteoblast precursors is sufficient to suppress normal osteoblast differentiation and to promote OS phenotypes through induction of oncogenic molecules such as FOXM1 and CYR61 in a β-catenin-independent manner. Conversely, inhibition of SFRP2, FOXM1, or CYR61 represses the tumorigenic potential. In summary, these findings demonstrate the oncogenic role of SFRP2 in the development of p53 mutation-associated OS and that inhibition of SFRP2 is a potential therapeutic strategy.