miR-200c and phospho-AKT as prognostic factors and mediators of osteosarcoma progression and lung metastasis

Functional role of MicroRNA/PI3K/AKT axis in osteosarcoma

Osteosarcoma (OS) is a primary malignant bone tumor that occurs in children and adolescents, and the PI3K/AKT pathway is overactivated in most OS patients. MicroRNAs (miRNAs) are highly conserved endogenous non-protein-coding RNAs that can regulate gene expression by repressing mRNA translation or degrading mRNA. MiRNAs are enriched in the PI3K/AKT pathway, and aberrant PI3K/AKT pathway activation is involved in the development of osteosarcoma. There is increasing evidence that miRNAs can regulate the biological functions of cells by regulating the PI3K/AKT pathway. MiRNA/PI3K/AKT axis can regulate the expression of osteosarcoma-related genes and then regulate cancer progression. MiRNA expression associated with PI3K/AKT pathway is also clearly associated with many clinical features. In addition, PI3K/AKT pathway-associated miRNAs are potential biomarkers for osteosarcoma diagnosis, treatment and prognostic assessment. This article reviews recent research advances on the role and clinical application of PI3K/AKT pathway and miRNA/PI3K/AKT axis in the development of osteosarcoma.

Delineating the tumour-regulatory roles of EYA4

Eyes absent homolog 4 (EYA4) is a protein that regulates many vital cellular processes and organogenesis pathways. It possesses phosphatase, hydrolase, and transcriptional activation functions. Mutations in the Eya4 gene can cause sensorineural hearing loss and heart disease. In most non-nervous system cancers such as those of the gastrointestinal tract (GIT), hematological and respiratory systems, EYA4 acts as a putative tumor suppressor. However, in nervous system tumors such as glioma, astrocytoma, and malignant peripheral nerve sheath tumor (MPNST), it plays a putative tumor-promoting role. EYA4 interacts with various signaling proteins of the PI3K/AKT, JNK/cJUN, Wnt/GSK-3β, and cell cycle pathways to exert its tumor-promoting or tumor-suppressing effect. The tissue expression level and methylation profiles of Eya4 can help predict the prognosis and anti-cancer treatment response among cancer patients. Targeting and altering Eya4 expression and activity could be a potential therapeutic strategy to suppress carcinogenesis. In conclusion, EYA4 may have both putative tumor-promoting and tumor-suppressing roles in different human cancers and has the potential to serve as a prognostic biomarker and therapeutic agent in various cancer types.

The clinical utility of dysregulated microRNA expression in paediatric solid tumours

MicroRNAs (miRNAs) are short, non-protein-coding genes that regulate the expression of numerous protein-coding genes. Their expression is dysregulated in cancer, where they may function as oncogenes or tumour suppressor genes. As miRNAs are highly resistant to degradation, they are ideal biomarker candidates to improve the diagnosis and clinical management of cancer, including prognostication. Furthermore, miRNAs dysregulated in malignancy represent potential therapeutic targets. The use of miRNAs for these purposes is a particularly attractive option to explore for paediatric malignancies, where the mutational burden is typically low, in contrast to cancers affecting adult patients. As childhood cancers are rare, it has taken time to accumulate the necessary body of evidence showing the potential for miRNAs to improve clinical management across this group of tumours. Here, we review the current literature regarding the potential clinical utility of miRNAs in paediatric solid tumours, which is now both timely and justified. Exploring such avenues is warranted to improve the management and outcomes of children affected by cancer.

Cell cycle associated miRNAs as target and therapeutics in lung cancer treatment

Lung cancer is the primary cause of cancer related deaths worldwide. Limited therapeutic options and resistance to existing drugs are the major hindrances to the clinical success of this cancer. In the past decade, several studies showed the role of microRNA (miRNA) driven cell cycle regulation in lung cancer progression. Therefore, these small nucleotide molecules could be utilized as promising tools in lung cancer therapy. In this review, we highlighted the recent advancements in lung cancer therapy using cell cycle linked miRNAs. By highlighting the roles of the specific cell cycle core regulators affiliated miRNAs in lung cancer, we further outlined how these miRNAs can be explored in early diagnosis and treatment strategies to prevent lung cancer. With the provided information from our review, more medical efforts can ensure a potential breakthrough in miRNA-based lung cancer therapy.

Research progress of bone-targeted drug delivery system on metastatic bone tumors

Bone metastases are common in malignant tumors and the effect of conventional treatment is limited. How to effectively inhibit tumor bone metastasis and deliver the drug to the bone has become an urgent issue to be solved. While bone targeting drug delivery systems have obvious advantages in the treatment of bone tumors. The research on bone-targeted anti-tumor therapy has made significant progress in recent years. We introduced the related tumor pathways of bone metastases. The tumor microenvironment plays an important role in metastatic bone tumors. We introduce a drug-loading systems based on different environment-responsive nanocomposites for anti-tumor and anti-metastatic research. According to the process of bone metastases and the structure of bone tissue, we summarized the information on bone-targeting molecules. Bisphosphate has become the first choice of bone-targeted drug delivery carrier because of its affinity with hydroxyapatite in bone. Therefore, we sought to summarize the bone-targeting molecule of bisphosphate to identify the modification effect on bone-targeting. And this paper discusses the relationship between bisphosphate bone targeting molecular structure and drug delivery carriers, to provide some new ideas for the research and development of bone-targeting drug delivery carriers. Targeted therapy will make a more outstanding contribution to the treatment of tumors.

APE1 controls DICER1 expression in NSCLC through miR-33a and miR-130b

Increasing evidence suggests different, not completely understood roles of microRNA biogenesis in the development and progression of lung cancer. The overexpression of the DNA repair protein apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1) is an important cause of poor chemotherapeutic response in lung cancer and its involvement in onco-miRNAs biogenesis has been recently described. Whether APE1 regulates miRNAs acting as prognostic biomarkers of lung cancer has not been investigated, yet. In this study, we analyzed miRNAs differential expression upon APE1 depletion in the A549 lung cancer cell line using high-throughput methods. We defined a signature of 13 miRNAs that strongly correlate with APE1 expression in human lung cancer: miR-1246, miR-4488, miR-24, miR-183, miR-660, miR-130b, miR-543, miR-200c, miR-376c, miR-218, miR-146a, miR-92b and miR-33a. Functional enrichment analysis of this signature revealed its biological relevance in cancer cell proliferation and survival. We validated DICER1 as a direct functional target of the APE1-regulated miRNA-33a-5p and miR-130b-3p. Importantly, IHC analyses of different human tumors confirmed a negative correlation existing between APE1 and Dicer1 protein levels. DICER1 downregulation represents a prognostic marker of cancer development but the mechanisms at the basis of this phenomenon are still completely unknown. Our findings, suggesting that APE1 modulates DICER1 expression via miR-33a and miR-130b, reveal new mechanistic insights on DICER1 regulation, which are of relevance in lung cancer chemoresistance and cancer invasiveness.

Regulatory mechanisms and potential medical applications of HNF1A-AS1 in cancers

Long noncoding RNAs (lncRNAs) are defined as a class of non-protein-coding RNAs that are longer than 200 nucleotides. Previous studies have shown that lncRNAs play a vital role in the progression of multiple diseases, which highlights their potential for medical applications. The lncRNA hepatocyte nuclear factor 1 homeobox A (HNF1A) antisense RNA 1 (HNF1A-AS1) is known to be abnormally expressed in multiple cancers. HNF1A-AS1 exerts its oncogenic roles through a variety of molecular mechanisms. Moreover, aberrant HNF1A-AS1 expression is associated with diverse clinical features in cancer patients. Therefore, HNF1A-AS1 is a promising biomarker for tumor diagnosis and prognosis and thus a potential candidate for tumor therapy. This review summarizes current studies on the role and the underlying mechanisms of HNF1A-AS1 various cancer types, including gastric cancer, liver cancer, glioma, lung cancer, colorectal cancer, breast cancer, bladder cancer, osteosarcoma, esophageal adenocarcinoma, hemangioma, oral squamous cell carcinoma, laryngeal squamous cell carcinoma, cervical cancer, as well as gastroenteropancreatic neuroendocrine neoplasms. We also describe the diagnostic, prognostic, and therapeutic value of HNF1A-AS1 for multiple cancer patients.

Osteoclasts differential-related prognostic biomarker for osteosarcoma based on single cell, bulk cell and gene expression datasets

Osteosarcoma (OS) is one of the most common primary bone malignant tumors. Osteoclasts have been shown to have a valuable role in OS. In the present study, we analyzed the differentiation states of osteoclasts in OS and their prognostic significance based on integrated scRNA-seq and bulk RNA-seq data. Osteoclasts in distinct differentiation states were characterized, and 661 osteoclasts differentiation-related genes (ODRGs) were obtained. ORDGs in distinct differentiation states were enriched in distinct functions and pathways. TPM1, S100A13, LOXL1, PSMD10, ST3GAL4, PEF1, SERPINE2, TUBB, FAM207A, TUBA1A, and DCN were identified as the significant survival-predicting ODRGs. We successfully developed a risk score model based on these survival-predicting ODRGs. In addition, we generated a nomogram applicable for clinical with both ODRGs signatures and clinicopathological parameters, and validated in OS cohorts to predict OS patient outcome. This study proposed and verified the important roles of osteoclasts differentiation in the prognosis of patients with OS, suggesting promising therapeutic targets for OS.

Polygonum cuspidatum inhibits the growth of osteosarcoma cells via impeding Akt/ERK/EGFR signaling pathways

Osteosarcoma (OS), the most prevalent bone malignancy, mainly affects children and adolescents. Despite recent advances in multimodal therapy, the overall survival rate for OS patients remains poor. Chinese herb medicine (CHM) is an alternative therapeutic option for multifaceted diseases such as malignant tumors. For centuries in China, polygonum cuspidatum, a classic CHM, has been used to treat several diseases, nevertheless, the mechanisms underlying its therapeutic effects have not been fully elucidated. Through network pharmacology and bioinformatic tools, we evaluated the pharmacological activity of polygonum cuspidatum. We found that it has a potential therapeutic effect on malignant tumors, which was subsequently verified by intragastric administration of polygonum cuspidatum to OS cell xenografted mice models. Next, to establish the action mechanism of polygonum cuspidatum, we built a disease/drug-target PPI network that was made up of 250 core treatment targets against OS using Cytoscape software. Enrichment evaluation for the above targets indicated that polygonum cuspidatum may exert its effects on the cell cycle and apoptosis of OS cells through inhibiting Akt/ERK/EGFR pathways. Finally, the above in silico results were experimentally validated via a series of molecular biological and cell functional analyses. Taken together, the findings show that polygonum cuspidatum has a significant potential for OS treatment, which provides a novel insight into the discovery of CHM-based drug against malignancies.

Periostin promotes the proliferation and metastasis of osteosarcoma by increasing cell survival and activates the PI3K/Akt pathway

Background

Silencing of the periostin gene (POSTN) can inhibit the biological process of several different cancers, and this inhibition may be related to down-regulation of PI3K/AKT signaling. However, the effect of POSTN on the progression, proliferation, and invasion of osteosarcoma (OS) remain unclear.

Methods

We used the Gene Expression Omnibus (GEO) database to screen datasets on in situ OS and lung metastases to identify core genes and potential pathways. We used additional bioinformatics tools to identify protein–protein interactions (PPIs) and gene networks, and selected the top seven genes whose expression had the strongest correlations with other genes.

Results

The results indicated that POSTN was a major hub gene. Subsequent analysis of gene expression profiles showed that POSTN was highly expressed in 262 cases with sarcoma and expression was closely related to poor prognosis. We also performed enrichment analysis to identify differentially expressed genes and used real-time PCR, western blotting, and immunohistochemistry analyses to measure POSTN expression in cells and tissues. Transfection of a POSTN-shRNA plasmid into cultured OS cells (Saos-2) effectively inhibited the proliferation, invasion, and migration of these cells. Taken together, our results suggest that POSTN may play a role in promoting the proliferation and metastasis of OS by activation of the PI3K/Akt signaling pathway.

Conclusions

Our results provide a preliminary characterization of the mechanism by which POSTN may regulate the migration and invasion of OS cells and also provide a theoretical basis for identifying biomarkers that have potential use for the diagnosis and treatment of OS.

Advances in the Biological Functions and Mechanisms of miRNAs in the Development of Osteosarcoma

Osteosarcoma is one of the most common primary malignant bone tumors, mainly occurring in children and adolescents, and is characterized by high morbidity and poor prognosis. MicroRNAs, a class of noncoding RNAs consisting of 19 to 25 nucleotides, are involved in cell proliferation, invasion, metastasis, and apoptosis to regulate the development and progression of osteosarcoma. Studies have found that microRNAs are closely related to the diagnosis, treatment, and prognosis of osteosarcoma patients and have an important role in improving drug resistance in osteosarcoma. This paper reviews the role of microRNAs in the pathogenesis of osteosarcoma and their clinical value, aiming to provide a new research direction for diagnosing and treating osteosarcoma and achieving a better prognosis.

Circle RNA circCSPP1 promotes human osteosarcoma cell proliferation and increases glucose metabolism by suppressing miR-200c maturation

INTRODUCTION

MiR-200c plays a central role in glucose metabolism in cancer cells. However, its upstream regulators in this process are unknown. CircRNA CSPP1 (circCSPP1) was predicted to bind to premature miR-200c, an oncogenic miRNA. Therefore, we explored their interaction in osteosarcoma (OS).

METHODS

Differential circCSPP1 and miR-200c expression in OS was analyzed using RT-qPCR. Glucose metabolism was analyzed by glucose uptake assay. Subcellular circCSPP1 location in OS cells was detected using cellular fractionation assay. The direct interaction between circCSPP1 and miR-200c was explored using RNA-RNA pull-down assay. The role of circCSPP1 in miR-200c maturation was investigated by analyzing both mature and premature miR-200c levels in OS cells with circCSPP1 overexpression.

RESULTS

CircCSPP1 and premature miR-200c levels were increased while mature miR-200c level was decreased in OS. CircCSPP1 was detected in both the nuclear and cytoplasm fractions of OS cells. CircCSPP1 directly interacted with premature miR-200c. CircCSPP1 overexpression increased premature miR-200c level, glucose uptake, and cell proliferation, but decreased mature miR-200c level. MiR-200c overexpression suppressed the role of circCSPP1 in OS cells.

CONCLUSIONS

CircCSPP1 promotes OS cell proliferation and increases glucose metabolism by suppressing miR-200c maturation.

miR-877-3p inhibits tumor growth and angiogenesis of osteosarcoma through Fibroblast Growth Factor 2 signaling

Osteosarcoma (OS) is the most common high-grade malignant bone tumor in teenagers. MicroRNAs can function as posttranscriptional regulators of gene expression, playing critical roles in cancer dev-877-3p in OS. Quantitative real-time RT-PCR was carried out for detecting miR-877-3p expression in OS. The effects of miR-877-3p on proliferation was analyzed via MTT, colony formation, and flow cytometry assays. Angiogenesis of endothelial cells were investigated by wound healing and tube formation assay. Gene profiling based on PCR array and luciferase reporter assay were conducted to determine target genes of miR-877-3p. In-vivo study was used to determine the effects of miR-877-3p on the tumor growth. The expression of miR-877-3p was markedly downregulated in OS tissues and cell lines. Low expression of miR-877-3p predicts poor prognosis of OS patients. miR-877-3p overexpression was found to inhibit the proliferation of OS cell lines. The angiogenesis assays showed that miR-877-3p attenuated the angiogenesis. Further mechanism studies showed that miR-877-3p can reduce (Fibroblast Growth Factor 2) FGF2 expression in OS cells by binding to the 3’UTR end of FGF2. Moreover, increased expression of miR-877-3p was responsible for the inhibition of tumor growth and angiogenesis. Taken together, our findings indicated that miR-877-3p might exhibit tumor suppressive role by targeting FGF2 signaling, which may serve as potential target for OS.

Differential gene expression analysis for osteosarcoma lung metastases

PURPOSE

To explore the exact molecular mechanisms underline osteosarcoma (OS) patients with lung metastases.

METHODS

The differentially expressed gene (DEG) as well as differentially expressed miRNAs (DEMs) for OS lung metastases were deeply investigated with two independent sources of databases (GEO dataset and clinical participants); The enriched biological processes and signaling pathways were explored; the miRNAs-mRNAs network was constructed; the functions of potential DEGs and DEMs were also verified with external analysis.

RESULTS

The OS patients with lung metastases displayed 323 DEGs as C-C motif chemokine ligand 3 (CCL3), sorting nexin 10 (SNX10), alpha-2-macroglobulin (A2M), carboxypeptidase E (CPE), Rap guanine nucleotide exchange factor 4 (RAPGEF4), PDZ domain containing 2 (PDZD2), calpain 10 (CAPN10), four and a half LIM domains 2 (FHL2), alkaline phosphatase, biomineralization associated (ALPL), interleukin 6 (IL6), solute carrier family 26 member 1 (SLC26A1) as well as smoothened, frizzled class receptor (SMO) were significant differentially expressed. At the same time, 21 DEMs were potential for the progress of OS lung metastasis with hsa-miR-638, hsa-miR-451, hsa-miR-486-5p, hsa-miR-134 and hsa-miR-648 were significant distinct. It could been shown that hsa-miR-638 manipulated the largest number of target genes. The functions of hsa-miR-638 and target mRNAs for the development of lung metastasis in OS could be confirmed by quantitative Real-time PCR analysis.

CONCLUSION

This integrated study hypothesized several miRNA dependent signaling pathway for OS patients with lung metastases and initiated a potential strategy for better understanding the lung metastases in clinic.

Unraveling the roles of miRNAs in regulating epithelial-to-mesenchymal transition (EMT) in osteosarcoma

Osteosarcoma is one of the most prevalent primary bone tumors with a high metastatic and recurrence rate with poor prognosis. MiRNAs are short and non-coding RNAs that could regulate various cellular activities and one of them is the epithelial-to-mesenchymal transition (EMT). Osteosarcoma cells that have undergone EMT would lose their cellular polarity and acquire invasive and metastatic characteristics. Our literature search showed that many pre-clinical and clinical studies have reported the roles of miRNAs in modulating the EMT process in osteosarcoma and compared to other cancers like breast cancer, there is a lack of review article which effectively summarizes the various roles of EMT-regulating miRNAs in osteosarcoma. This review, therefore, was aimed to discuss and summarize the EMT-promoting and EMT-suppressing roles of different miRNAs in osteosarcoma. The review would begin with the discussion on the concepts and principles of EMT, followed by the exploration of the diverse roles of EMT-regulating miRNAs in osteosarcoma. Subsequently, the potential use of miRNAs as prognostic biomarkers in osteosarcoma to predict the likelihood of metastases and as therapeutic agents would be discussed.

Research models and mesenchymal/epithelial plasticity of osteosarcoma

Most osteosarcomas (OSs) develop from mesenchymal cells at the bone with abnormal growth in young patients. OS has an annual incidence of 3.4 per million people and a 60-70% 5-year surviving rate. About 20% of OS patients have metastasis at diagnosis, and only 27% of patients with metastatic OS survive longer than 5 years. Mutation of tumor suppressors RB1, TP53, REQL4 and INK4a and/or deregulation of PI3K/mTOR, TGFβ, RANKL/NF-κB and IGF pathways have been linked to OS development. However, the agents targeting these pathways have yielded disappointing clinical outcomes. Surgery and chemotherapy remain the main treatments of OS. Recurrent and metastatic OSs are commonly resistant to these therapies. Spontaneous canine models, carcinogen-induced rodent models, transgenic mouse models, human patient-derived xenograft models, and cell lines from animal and human OSs have been developed for studying the initiation, growth and progression of OS and testing candidate drugs of OS. The cell plasticity regulated by epithelial-to-mesenchymal transition transcription factors (EMT-TFs) such as TWIST1, SNAIL, SLUG, ZEB1 and ZEB2 plays an important role in maintenance of the mesenchymal status and promotion of cell invasion and metastasis of OS cells. Multiple microRNAs including miR-30/9/23b/29c/194/200, proteins including SYT-SSX1/2 fusion proteins and OVOL2, and other factors that inhibit AMF/PGI and LRP5 can suppress either the expression or activity of EMT-TFs to increase epithelial features and inhibit OS metastasis. Further understanding of the molecular mechanisms that regulate OS cell plasticity should provide potential targets and therapeutic strategies for improving OS treatment.

Non-coding RNAs in Wilms' tumor: biological function, mechanism, and clinical implications

Non-coding RNAs are involved with maintenance and regulation of physiological mechanisms and are involved in pathological processes, such as cancer. Among the small ncRNAs, miRNAs are the most explored in tumorigenesis, metastasis development, and resistance to chemotherapy. These small molecules of ~ 22 nucleotides are modulated during early renal development, involved in the regulation of gene expression and Wilms' tumor progression. Wilms' tumors are embryonic tumors with few mutations and complex epigenetic dysregulation. In recent years, the small ncRNAs have been explored as potentially related both in physiological development and in the tumorigenesis of several types of cancer. Besides, genes regulated by miRNAs are related to biological pathways as PI3K, Wnt, TGF-β, and Hippo signaling pathways, among others, which may be involved with the underlying mechanisms of resistance to chemotherapy, and in this way, it has emerged as potential targets for cancer therapies, including for Wilms' tumors.

Bio-analytical Identification of Key Genes that Could Contribute to the Progression and Metastasis of Osteosarcoma

Background:

Osteosarcoma (OS) is one of the most common primary malignant bone tumors in children and adolescents. OS metastasis has been a challenge in the treatment of OS. The present study screened progression related genes in OS by analyzing a public dataset GSE42352, and identified 691 up-regulated and 945 down-regulated genes in advanced stage OS compared to early-stage OS samples.

Methods:

Protein-protein interaction (PPI) networks were further employed to reveal the interaction among these genes. Bioinformatics analysis showed that progression related differently expressed genes (DEGs) were significantly associated with the regulation of cell proliferation and metabolisms.

Results:

This study revealed that progression related DEGs were dysregulated in metastatic OS compared to non-metastatic OS samples. Further analysis showed CSF1R, CASP1, CD163, AP1B1, LAPTM5, PEX19, SLA, STAB1, YWHAH, PLCB2, and GPR84 were associated with the metastasis-free survival time in patients with OS.

Conclusions:

These findings provided novel information for us to understand the mechanisms underlying the progression and metastasis of OS.

Study on Targeting Relationship Between miR-320b and FGD5-AS1 and Its Effect on Biological Function of Osteosarcoma Cells

Objective

To probe into the expression of FGD5-AS1 in osteosarcoma and its relationship with miR-320b.

Methods

The tissue and serum samples of 97 patients with osteosarcoma were collected, and the serum samples of 100 healthy subjects who concurrently underwent physical examination were selected as the control. FGD5-AS1 expression in tissues and serum was detected, and osteosarcoma cells were transfected to measure cell behaviors such as proliferation, invasion and apoptosis.

Results

FGD5-AS1 was highly expressed in osteosarcoma, and its elevated expression indicated poor survival of patients. Serum FGD5-AS1 was related to tumor size and clinical stage and could be used for the diagnosis of osteosarcoma. The study of osteosarcoma cell lines U2OS and SaOS-2 showed that after inhibiting FGD5-AS1, the viability and invasion capacity of osteosarcoma cells decreased statistically compared with the control group (CG), while the apoptosis ability could be improved by further regulating apoptotic proteins (P<0.05). Detection of EMT-related proteins identified that E-cadherin increased while N-cadherin decreased significantly after FGD5-AS1 inhibition (P<0.05). Correlation analysis revealed a negative correlation between miR-320b and FGD5-AS1 (r = −0.410, P<0.001). Overexpression of miR-320b significantly inhibited cell viability, invasion and EMT ability, and increased the apoptosis rate, while inhibiting miR-320b expression produced the opposite results. The targeting relationship between miR-320b and FGD5-AS1 was confirmed through the biological prediction website, luciferase assay and RNA binding protein immunoprecipitation (RIP) assay. Inhibition of miR-320b could reverse the regulatory effect of FGD5-AS1 knockdown on osteosarcoma cells.

Conclusion

FGD5-AS1 is highly expressed in osteosarcoma and is involved in the biological procession of osteosarcoma by targeting miR-320b.

CONUT Score or/and Peripheral Blood CD4+/CD8+ Ratio-Based Web Dynamic Nomograms to Predict the Individualized Survival of Patients with Advanced Osteosarcoma

Background

Nutritional and immune status is paramount for the overall survival (OS) of patients with advanced osteosarcoma. Comprehensive prognostic predictors based on the two indices are scarce. This study aimed to construct and validate individualized web dynamic nomograms based on CONUT score or/and peripheral blood CD4+/CD8+ ratio for OS in patients with advanced osteosarcoma.

Materials and Methods

The clinical data of 376 advanced osteosarcoma patients from January 2000 to December 2019 were retrospectively collected. Data from the 301 patients (diagnosed in the first 15 years) were used as the development set and data from the remaining 75 patients were assigned as the validation set. Multivariate Cox regression analyses were conducted and three prediction models were constructed, namely, CD4+/CD8+ ratio univariate model (model 1), CONUT score univariate model (model 2), and CD4+/CD8+ ratio plus CONUT score (model 3). These models were visualized by conventional nomograms and individualized web dynamic nomograms, and their performances were further evaluated by C-index, calibration curve, receiver operating characteristic (ROC) curve, and decision curve analysis (DCA), respectively.

Results

In multivariate Cox analysis, age, metastasis, ALP, CD4+/CD8+ ratio, chemotherapy, and CONUT score were identified as independent prognostic factors for OS. The calibration curves of the three models all showed good agreement between the actual observation and nomogram prediction for 1-year overall survival. In the development set, the C-index and area under the curve (AUC) of model 3 (0.837, 0.848) were higher than that of model 1 (0.765, 0.773) and model 2 (0.712, 0.749). Similar trends were observed in the validation set. The net benefits of model 3 were better than the other two models within the threshold probability of 36–80% in DCA.

Conclusion

CONUT score and peripheral CD4+/CD8+ ratio are easily available, reliable, and economical prognostic predictors for survival prediction and stratification in patients with advanced osteosarcoma, but the two predictors combined can establish a better prognosis prediction model.

Identification Of Actionable Genetic Targets In Primary Cardiac Sarcomas

BACKGROUND

Primary cardiac tumors are extremely rare; most are myxomas with a benign prognosis. However, primary sarcomas are highly aggressive and treatment options are limited. Radical surgery is often not feasible and conventional therapies provide only modest results. Due to the rare nature of primary cardiac tumors, there are no proper randomized studies to guide treatment. Their complexity requires alternative approaches in order to improve treatment efficacy.

METHODS

We isolated DNA from 5 primary cardiac sarcomas; the quality of DNA from 3 of them was sufficient to perform high-resolution single nucleotide polymorphism (SNP) array analysis.

RESULTS

In the present study, molecular karyotyping revealed numerous segmental chromosomal alterations and amplifications affecting actionable genes that may be involved in disease initiation and/or progression. These include chromosomal break flanking AKT2 in undifferentiated pleomorphic rhabdomyosarcoma, chromosomal break in promoter of TERT, and gain of CDK4 and amplification of MDM2 in inflammatory myofibroblastic tumor. We detected segmental break flanking MOS in high-grade myxofibrosarcoma. In addition, the high number of chromosomal aberrations in high-grade myxofibrosarcoma may cause multiple tumor-specific epitopes, supporting the study of immunotherapy treatment in this type of aggressive tumor.

CONCLUSION

Our results provide a genetic rationale that supports an alternative, personalized therapeutic management of primary cardiac sarcomas.

Protein Kinase B and Extracellular Signal-Regulated Kinase Inactivation is Associated with Regorafenib-Induced Inhibition of Osteosarcoma Progression In Vitro and In Vivo

Osteosarcoma is the most common type of bone cancer. Multimodality treatment involving chemotherapy, radiotherapy and surgery is not effective enough to control osteosarcoma. Regorafenib, the oral multi-kinase inhibitor, has been shown to have positive efficacy on disease progression delay in chemotherapy resistant osteosarcoma patients. However anti-cancer effect and mechanism of regorafenib in osteosarcoma is ambiguous. Thus, the aim of this study is to investigate the efficacy and molecular mechanism of regorafenib on osteosarcoma in vitro and in vivo. Human osteosarcomas U-2 OS or MG-63 were treated with regorafenib, miltefosine (protein kinase B (AKT) inhibitor), or PD98059 (mitogen-activated protein/extracellular signal-regulated kinase (MEK) pathway inhibitor) for 24 or 48 h. Cell viability, apoptotic signaling transduction, tumor invasion, expression of tumor progression-associated proteins and tumor growth after regorafenib treatment were assayed by MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, flow cytometry, transwell assay, Western blotting assay and in vivo animal experiment, respectively. In these studies, we also indicated that regorafenib suppressed cell growth by prompting apoptosis of osteosarcoma cells, which is mediated through inactivation of ERK and AKT signaling pathways. After regorafenib treatment, downregulation of related genes in invasion (vascular endothelial growth factor (VEGF) and matrix metallopeptidase 9 (MMP-9)), proliferation (CyclinD1) and anti-apoptosis (X-linked inhibitor of apoptosis protein (XIAP), myeloid cell leukemia-1 (MCL-1), and cellular FLICE (FADD-like IL-1β-converting enzyme)-inhibitory protein (C-FLIP)) were found. Moreover, upregulation of caspase-3 and caspase-8 cleavage were also observed. In sum, we suggest that regorafenib has potential to suppress osteosarcoma progression via inactivation of AKT and ERK mediated signaling pathway.

Circulating Exosomal miR-141-3p and miR-375 in Metastatic Progression of Rectal Cancer

As many as 30% to 40% of locally advanced rectal cancer (LARC) patients experience metastatic progression of the disease. Recognizing the potential of the genetic cargo in tumor-derived exosomes, we hypothesized that plasma exosomal microRNA (miRNA) may reflect biological aggressiveness in LARC and provide new markers for rectal cancer aggressiveness and risk stratification. In a prospective LARC cohort (NCT01816607), plasma samples were collected from 29 patients at the time of diagnosis, before neoadjuvant therapy and surgery. Exosomes, precipitated from plasma using a commercial kit, were verified by cryo-electron microscopy, nanoparticle tracking analysis, and western blotting. Expression of exosomal miRNAs was profiled using a miRCURY LNA miRNA microarray and validation of six miRNAs associated with pathological and clinical end-points was undertaken in plasma collected at the time of diagnosis from 64 patients in an independent prospective LARC cohort (NCT00278694). In both cohorts, exosomal miR-141-3p and miR-375 were higher in patients with synchronous liver metastasis than in those without (P = .010 and P = .017 respectively in the investigative cohort, and P < .001 for both in the validation cohort). Further, high exosomal miR-141-3p was associated with post-operative metastatic liver progression in the investigative cohort (P = .034). Because both miRNAs are associated with tumor angiogenesis and immune modulation, we propose that these miRNAs in circulating exosomes may reflect rectal cancer aggressiveness and accordingly be candidate biomarkers for further investigations.

MicroRNA-200c-3p/ZEB2 loop plays a crucial role in the tumor progression of prostate carcinoma

Background

The microRNA (miRNA) miR-200c-3p is involved in the tumorigenesis and progression of a variety of cancers. However, the underlying regulatory role of miR-200c-3p in prostate cancer (PCa) remains unclear.

Methods

Online databases including Oncomine, Linkedomics and StarBase were used to investigate the clinical significance of miR-200c-3p, along with associated gene targets. PCa tissues and adjacent normal tissues were used for the detection of miR-200c-3p expression. A lentivirus overexpressing miR-200c-3p was constructed and transfected into PC3 and DU145 cells. Cell formation of proliferation, migration, and invasion were determined by cell viability and colony-formation assay, wound healing assay, and Matrigel invasion assay, respectively. Epithelial-mesenchymal transition (EMT)-associated markers were determined by qRT-PCR and Western blot. A luciferase reporter assay was performed to determine the direct relationship of miR-200c-3p and ZEB2. The tumor-suppressive role of miR-200c-3p was further confirmed by a xenograft tumor model and immunohistochemical (IHC) staining.

Results

Online database analyses showed that miR-200c-3p was associated with pathologic T and N stage in PCa, and miR-200c-3p was downregulated in PCa tissues. Overexpression of miR-200c-3p was considered a tumor suppressor and was found to significantly suppress the formation of migration and invasion in PCa cells via repression of E-cadherin-induced EMT. The bioinformatic database indicated that ZEB2 has a significant correlation with miR-200c-3p and was upregulated in PCa tissues. Further, ZEB2 expression was suppressed by the upregulation of miR-200c-3p and was identified as a direct target of miR-200c-3p. In addition, repression of ZEB2 could restore the levels of miR-200c-3p in PCa cells in turn, suggesting a potential negative loop between miR-200c-3p and ZEB2. miR-200c-3p also had an antitumor effect by negatively regulating ZEB2 in a xenograft mouse model.

Conclusions

Taken together, the results of our study demonstrated the novel regulatory loop of miR-200c-3/ZEB2 in PCa progression, providing effective therapeutic strategies for PCa in the future.

The proliferation and invasion of osteosarcoma are inhibited by miR-101 via targetting ZEB2

Having a better grasp of the molecular mechanisms underlying carcinogenesis and progression in osteosarcoma would be helpful to find novel therapeutic targets. Different types of cancers have presented abnormal expression of miRNA-101 (miR-101). Nevertheless, we still could not figure out what expression of miR-101 in human osteosarcoma is and its biological function. Thus, we conducted the present study to identify its expression, function, and molecular mechanism in osteosarcoma. We detected the expression of miR-101 in osteosarcoma samples and cell lines. The effects of miR-101 on osteosarcoma cells’ proliferation and invasion were evaluated. Luciferase reporter assay was applied to identify the direct target of miR-101. Compared with adjacent normal specimens and normal bone cell line by using qPCR, the expression levels of miR-101 in osteosarcoma specimens and human osteosarcoma cell lines distinctly decreased. According to function assays, we found that overexpression of miR-101 significantly inhibited the cell proliferation and invasion in osteosarcoma cells. Moreover, we confirmed that zinc finger E-box binding homeobox 2 (ZEB2) was a direct target of miR-101. In addition, overexpression of ZEB2 could rescue the inhibition effect of proliferation and invasion induced by miR-101 in osteosarcoma cells. MiR-101 has been proved to be down-regulated in osteosarcoma and has the ability to suppress osteosarcoma cell proliferation and invasion by directly targetting ZEB2.

Effect of lncRNA ANRIL knockdown on proliferation and cisplatin chemoresistance of osteosarcoma cells in vitro

Chemoresistance is a major obstacle in treating cancer, including osteosarcoma. LncRNA ANRIL (ANRIL) is involved in the growth and metastasis of osteosarcoma cells, however, its role in chemoresistance remains unclear. In this study, ANRIL shRNA was used to knock down its endogenous expression in U2-OS and Saos-2 osteosarcoma cell lines. Our data showed that ANRIL-silenced cells were more sensitive to cisplatin: apoptotic ratio was increased and cleaved caspase-3 level was upregulated. Furthermore, the expression level of miR-125a-5p, a microRNA that can bind to ANRIL, was elevated in ANRIL-silenced cells. MiR-125a-5p inhibitor attenuated ANRIL knockdown-induced chemosensitivity to cisplatin. In addition, ANRIL knockdown resulted in a reduction in STAT3, a target of miR-125a-5p, in osteosarcoma cells. Forced overexpression of STAT3 weakened the chemosensitivity of ANRIL-silenced cells to cisplatin. In conclusion, our study demonstrates that ANRIL knockdown sensitizes osteosarcoma cells to cisplatin-induced cytotoxicity, suggesting ANRIL as a therapeutic target for osteosarcoma chemotherapy.

Roles of miR-200 family members in lung cancer: more than tumor suppressors

miRNAs are a class of single-stranded noncoding RNAs, which have no coding potential, but modulate many molecular mechanisms including cancer pathogenesis. miRNAs participate in cell proliferation, differentiation, apoptosis, as well as carcinogenesis or cancer progression, and their involvement in lung cancer has been recently shown. They are suggested to have bidirectional functions on important cancer-related genes so as to enhance or attenuate tumor genesis. Epithelial-mesenchymal transition (EMT) is a fundamental process which contributes to integrity of organogenesis and tissue differentiation as well as tissue repair, organ fibrosis and the progression of carcinoma, and several miRNAs were suggested to form the network regulating EMT in lung cancer, among which, miR-200 family members (miR-200a, miR-200b, miR-200c, miR-429 and miR-141) play crucial roles in the suppression of EMT.

Prognostic significance of cyclooxygenase 2 and phosphorylated Akt1 overexpression in primary nonmetastatic and metastatic cutaneous melanomas

Cyclooxygenase 2 (COX-2) and phosphorylated Akt1 (p-Akt1) are associated with tumor spreading, cell proliferation, high metabolism, and angiogenesis in solid tumors. This study aimed to investigate COX-2 and p-Akt1 expression in primary and metastatic melanomas by correlating with the cellular proliferation index (as revealed by minichromosome maintenance 2 expression) and the outcome of patients with malignant melanomas. Seventy-seven biopsies of malignant melanomas, including 42 primary nonmetastatic melanomas (PNMMs), 12 primary metastatic melanomas (PMMs), and 23 metastatic melanomas (MMs), were retrospectively selected. Tissue microarrays were developed and submitted for immunohistochemical staining for COX-2, p-Akt1, and minichromosome maintenance 2. Increased COX-2 cytoplasmic staining patterns were observed in PMM and MM when compared with PNMM (P=0.0011). Higher nuclear and cytoplasmic expression of p-Akt1 was more closely associated with PMM than with MM and PNMM (P<0.00001). Coexpression of these biomarkers was closely correlated with lower overall survival rates in melanomas. Furthermore, we observed a statistically significant positive correlation between the mitosis index and increased COX-2 expression (P=0.0135) and between p-Akt1 (P=0.0038) and the cellular proliferation index (P=0.0060). Taken together, our findings demonstrate that COX-2 and p-Akt1 play an important combined role during melanoma progression and are associated with highly metastatic tumors and survival rates in patients with MM. In addition, these biomarkers can be used to predict melanoma prognosis independently of metastatic status. However, further studies are required to elucidate the biological role of these biomarkers during the progression of MM events.

TIMP3 Overexpression Improves the Sensitivity of Osteosarcoma to Cisplatin by Reducing IL-6 Production

Osteosarcoma is the most common bone cancer in children and adolescents. Tissue inhibitors of metalloproteinases (TIMPs)-3 inhibit matrix metalloproteinases to limit extracellular matrix degradation. Cisplatin is a widely used chemotherapeutic drug used to cure osteosarcoma. Interleukin (IL)-6 and TIMP3 play important roles in the drug resistance of osteosarcoma; however, their relationship in this process remains unclear. This study aimed to explore the role of TIMP3 in the cisplatin sensitivity of osteosarcoma and its underlying molecular mechanisms in vitro and in vivo. We compared TIMP3 expression levels between patients with cisplatin-sensitive and -insensitive osteosarcoma. TIMP3 was overexpressed or knocked down in the Saos2-lung cell line, which is a Saos2 subtype isolated from pulmonary metastases that has higher cisplatin chemoresistance than Saos2 cells. IL-6 expression, cell proliferation, sensitivity to cisplatin, migration, and invasion after TIMP3 overexpression or knockdown were determined. The same experiments were performed using MG63 and U2OS cells. Subsequently, luciferase-labeled Saos2-lung cells overexpressing TIMP3 were injected into the tibiae of nude mice treated with cisplatin. The results showed that IL-6 inhibited TIMP3 expression in Saos2 and Saos2-lung cells via signal transducer and activator of transcription 3 (STAT3) activation. STAT3 knockdown reversed the effect of IL-6. The expression of TIMP3 was higher in patients with cisplatin-sensitive osteosarcoma than in those with insensitive osteosarcoma. IL-6 expression was downregulated upon TIMP3 overexpression, and upregulated by TIMP3 knockdown. TIMP3 overexpression suppressed cell proliferation and enhanced cisplatin sensitivity by activating apoptosis-related signal pathways and inhibiting IL-6 expression in vitro and in vivo. In conclusion, cisplatin sensitivity correlated positively with TIMP3 expression, which is regulated by the IL-6/TIMP3/caspase pathway. The TIMP3 pathway could represent a target for new therapies to treat osteosarcoma.

miR-223-3p Inhibits Human Osteosarcoma Metastasis and Progression by Directly Targeting CDH6

Cadherin-6 (CDH6) is aberrantly expressed in cancer and closely associated with tumor progression. However, the functions of CDH6 in human osteosarcoma and the molecular mechanisms underlying CDH6 in osteosarcoma oncogenesis remain poorly understood. In this work, we assessed the role of CDH6 in human osteosarcoma and identified that the expression of CDH6 was closely related with the overall survival and poor prognosis of osteosarcoma patients. MicroRNAs (miRNAs) have been implicated as important epigenetic regulators during the progression of osteosarcoma. Using dual-luciferase reporter assays, we showed that miR-223-3p suppresses CDH6 expression by directly binding to the 3' UTR of CDH6. miR-223-3p overexpression significantly inhibited cell invasion, migration, growth, and proliferation by suppressing the CDH6 expression in vivo and in vitro. Besides, CDH6 overexpression in the miR-223-3p-transfected osteosarcoma cells effectively rescued the inhibition of cell invasion, migration, growth, and proliferation mediated by miR-223-3p. Additionally, Kaplan-Meier analysis suggests that the expression of miR-223-3p predicts favorable clinical outcomes for osteosarcoma patients. Moreover, the expression of miR-223-3p was downregulated in osteosarcoma patients and was negatively associated with the expression of CDH6. Collectively, these data highlight that miR-223-3p/CDH6 axis is an important novel pleiotropic regulator and could early predict the metastatic potential in human osteosarcoma treatments.

MicroRNA-200c Inhibits Epithelial-Mesenchymal Transition by Targeting the BMI-1 Gene Through the Phospho-AKT Pathway in Endometrial Carcinoma Cells In Vitro

Background

MicroRNA-200c (miR-200c) is a short non-coding RNA that has a role in tumorigenesis and cancer progression. The aims of this study were to investigate the role of miR-200c in cell migration and epithelial-mesenchymal transition (EMT) in endometrial carcinoma cells in vitro.

Material/Methods

Potential direct targets of miR-200c were identified through the TargetScan database. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used study the expression of miR-200c in the endometrial carcinoma cell lines, Ishikawa and JEC, in vitro. Cell migration was studied using transwell assays. Expression of the mesenchymal marker, N-cadherin, the epithelial marker, E-cadherin, the transcription factor, Slug, the BMI-1 protein, AKT, and p-AKT were measured using Western blot. Small interfering RNA (siRNA) was used to silence the BMI-1 gene to study the targeting effect.

Results

Over-expression of miR-200c in Ishikawa and JEC cells resulted in reduced cell migration and proliferation. Western blot showed that overexpression of miR-200c downregulated the expression of the BMI-1 protein, p-AKT, N-cadherin and Slug, and the expression E-cadherin was upregulated; silencing miR-200c reversed these results. Silencing the BMI-1 gene inhibited EMT and suppressed p-AKT in miR-200c-inhibited endometrial carcinoma cells by increasing E-cadherin expression, reducing the expression of N-cadherin and the EMT-associated transcription factor, Slug.

Conclusions

In endometrial carcinoma cells in vitro, miR-200c inhibited EMT by targeting the BMI-1 gene through the p-AKT pathway.

The role of p53-microRNA 200-Moesin axis in invasion and drug resistance of breast cancer cells

This study aimed to analyze the expression of microRNAs in relation to p53 status in breast cancer cells and to delineate the role of Moesin in this axis. We used three isogenic breast carcinoma cell lines MCF7 (with wild-type p53), 1001 (MCF7 with mutated p53), and MCF7-E6 (MCF7 in which p53 function was disrupted). MicroRNA expression was analyzed using microarray analysis and confirmed by real-time polymerase chain reaction. The 1001 clone with mutant p53 showed 22 upregulated and 25 downregulated microRNAs. The predicted targets of these 47 microRNAs were >700 human genes belonging to interesting functional groups such as stem cell development and maintenance. The most significantly downregulated microRNAs in the p53-mutant cell line were from the miR-200 family. We focused on miR-200c which targets many transcripts involved in epithelial-to-mesenchymal transition including Moesin. We found that Moesin was expressed in 1001 but not in its p53 wild-type parental MCF7 consistent with the observed mesenchymal features in the 1001, such as vimentin positivity, E-cadherin negativity, and ZEB1 positivity in addition to the morphological changes. After Moesin silencing, the p53-mutant cells 1001 reverted from mesenchymal-to-epithelial phenotype and showed subtle reduction in migration and invasion and loss of ZEB1 and SNAIL expression. Interestingly, Moesin silencing restored the 1001 sensitivity to Doxorubicin. These results indicate that loss of miR-200c, as a consequence of p53 mutation, can upregulate Moesin oncogene and thus promote carcinogenesis. Moesin may play a role in metastasis and drug resistance of breast cancer.

RhoGDIβ promotes Sp1/MMP-2 expression and bladder cancer invasion through perturbing miR-200c-targeted JNK2 protein translation

Our most recent studies demonstrate that RhoGDIβ is able to promote human bladder cancer (BC) invasion and metastasis in an X‐link inhibitor of apoptosis protein‐dependent fashion accompanied by increased levels of matrix metalloproteinase (MMP)‐2 protein expression. We also found that RhoGDIβ and MMP‐2 protein expressions are consistently upregulated in both invasive BC tissues and cell lines. In the present study, we show that knockdown of RhoGDIβ inhibited MMP‐2 protein expression accompanied by a reduction of invasion in human BC cells, whereas ectopic expression of RhoGDIβ upregulated MMP‐2 protein expression and promoted invasion as well. The mechanistic studies indicated that MMP‐2 was upregulated by RhoGDIβ at the transcriptional level by increased specific binding of the transcription factor Sp1 to the mmp‐2 promoter region. Further investigation revealed that RhoGDIβ overexpression led to downregulation of miR‐200c, whereas miR‐200c was able directly to target 3′‐UTR of jnk2mRNA and attenuated JNK2 protein translation, which resulted in attenuation of Sp1mRNA and protein expression in turn, inhibiting Sp1‐dependent mmp‐2 transcription. Collectively, our studies demonstrate that RhoGDIβ overexpression inhibits miR‐200c abundance, which consequently results in increases of JNK2 protein translation, Sp1 expression, mmp‐2 transcription, and BC invasion. These findings, together with our previous results showing X‐link inhibitor of apoptosis protein mediating mRNA stabilization of both RhoGDIβ and mmp‐2, reveal the nature of the MMP‐2 regulatory network, which leads to MMP‐2 overexpression and BC invasion.

LncRNA SNHG15 contributes to proliferation, invasion and autophagy in osteosarcoma cells by sponging miR-141

Background

LncRNA small nucleolar RNA host gene 15 (SNHG15) was reported to play an oncogenic role in tumors. However, the role of SNHG15 and its molecular mechanism in osteosarcoma (OS) cells are largely unknown.

Methods

qRT-PCR was performed to evaluate the expression levels of SNHG15 and miR-141 in OS tissues and cells. Cell transfection with different siRNAs, miRNAs or pcDNAs into U2OS and MG63 cells were carried out by Lipofectamine 2000. The effects of SNHG15 and miR-141 on OS cell proliferation, invasion and the levels of autophagy-related proteins were analyzed by MTT assay, Transwell invasion/migration assay and western blot, respectively. Luciferase reporter assay was used to confirm whether SNHG15 could directly interact with miR-141.

Results

We found that up-regulation of SNHG15 was inversely correlated with miR-141 expression in OS tissues. SNHG15 knockdown and miR-141 overexpression significantly suppressed cell proliferation, invasion, migration and autophagy while SNHG15 overexpression and miR-141 repression exhibited the opposite effects on OS cells. Besides, SNHG15 could directly interact with miR-141 and regulate its expression. Furthermore, miR-141 suppressing significantly overturned the inhibition on proliferation, invasion, migration and autophagy mediated by SNHG15 knockdown while miR-141 overexpression remarkably attenuated SNHG15 overexpression-induced proliferation, invasion, migration and autophagy in OS cells.

Conclusion

Our data showed that SNHG15 contributes to proliferation, invasion, migration and autophagy in OS by negatively regulating miR-141, providing a new potential target and prognostic biomarker for the treatment of OS.

Anti-proliferative, pro-apoptotic and anti-invasive effect of EC/EV system in human osteosarcoma

Osteosarcoma is the most common and aggressive bone tumor in children. The Endocannabinoid/Endovanilloid system has been proposed as anticancer target in tumor of different origins. This system is composed of two receptors (CB1 and CB2), the Transient Potential Vanilloid 1 (TRPV1) channel and their ligands and enzymes. CB1 is expressed mainly in central nervous system while CB2 predominantly on immune and peripheral cells. We investigated the effects of JWH-133 (CB2 agonist) and RTX (TRPV1 agonist) in six human Osteosarcoma cell lines: MG-63, U-2OS, MNNG/HOS, Saos-2, KHOS/NP, Hs888Lu, by Apoptosis and Migration-Assay. We also compared the effects of these compounds on Caspase-3, AKT, MMP-2 and Notch-1 regulation by Q-PCR and Western Blotting.

We observed an anti-proliferative, pro-apoptotic, anti-invasive effect. Our results show that both CB2 stimulation and TRPV1 activation, in different Osteosarcoma cell lines, can act on the same pathways to obtain the same effect, indicating the Endocannabinoid/Endovanilloid system as a new therapeutic target in Osteosarcoma.

CNOT1 cooperates with LMNA to aggravate osteosarcoma tumorigenesis through the Hedgehog signaling pathway

While treatments for childhood osteosarcoma have improved, the overall survival for this common type of bone cancer has not changed for three decades, and thus, new targets for therapeutic development are needed. To identify tumor-related proteins in osteosarcoma, we used isobaric tags in a relative and absolute quantitation proteomic approach to analyze the differentially expressed proteins between osteosarcoma cells and human osteoblastic cells. Through clinical screening and functional evaluation, CCR4-NOT transcription complex subunit 1 (CNOT1) correlated with the growth of osteosarcoma cells. To date, the mechanisms and regulatory roles of CNOT1 in tumors, including osteosarcoma, remain largely elusive. Here, we present evidence that knockdown of CNOT1 inhibits the growth of osteosarcoma in vitro and in vivo. Mechanistically, we observed that CNOT1 interacted with LMNA (lamin A) and functioned as a positive regulator of this intermediate filament protein. The RNA-seq analysis revealed that CNOT1 depletion inhibited the Hedgehog signaling pathway in osteosarcoma cells. A rescue study showed that the decreased growth of osteosarcoma cells and inhibition of the Hedgehog signaling pathway by CNOT1 depletion were reversed by LMNA overexpression, indicating that the activity of CNOT1 was LMNA dependent. Notably, the CNOT1 expression was significantly associated with tumor recurrence, Enneking stage, and poor survival in patients with osteosarcoma. Examination of clinical samples confirmed that CNOT1 expression positively correlated with LMNA protein expression. Taken together, these results suggest that the CNOT1-LMNA-Hedgehog signaling pathway axis exerts an oncogenic role in osteosarcoma progression, which could be a potential target for gene therapy.

miR-211-5p Suppresses Metastatic Behavior by Targeting SNAI1 in Renal Cancer

The Snail family transcriptional repressor 1 (SNAI1) is known to promote metastatic phenotypes in renal cell carcinoma (RCC). However, the mechanism by which SNAI1 promotes RCC metastasis remains largely unexplored. Here, bioinformatics and quantitative validation revealed that miR-211-5p was downregulated in metastatic RCC clinical specimens compared with nonmetastatic RCC tissues. Overexpression of miR-211-5p suppressed RCC cell migration and invasion via downregulation of SNAI1 expression. Luciferase reporter assays demonstrated that miR-211-5p directly targeted 3'-UTR of SNAI1. Furthermore, miR-211-5p decreased xenograft tumor weight and reduced in vivo tumor metastasis in mice. These findings indicate that miR-211-5p-mediated inhibition of SNAIL1 expression contributes to the suppression of RCC progression.Implications: Targeting the miR-211-5p/SNAI1 signaling pathway may be a novel therapeutic approach for the treatment of RCC metastasis. Mol Cancer Res; 15(4); 448-56. ©2017 AACR.

MicroRNA-373 Promotes Growth and Cellular Invasion in Osteosarcoma Cells by Activation of the PI3K/AKT-Rac1-JNK Pathway: The Potential Role in Spinal Osteosarcoma

Spinal osteosarcoma (OS) has been proven to be more difficult to treat owing to potently malignant metastasis. The present study aimed to explore the functional role of microRNA (miR)-373 in cell growth and invasion of OS cells, as well as its underlying mechanism. The expression of miR-373 was analyzed in spinal OS tissues and cell lines. MG-63 cells were transfected with the miR-373 mimic or inhibitor and/or treated with the phosphoinositide 3-kinase (PI3K) (LY294002) inhibitor or Ras-related C3 botulinum toxin substrate 1 (Rac) guanosine triphosphate (GTPase) (NSC23766) inhibitor, and then the impact of miR-373 aberrant expression on cell growth and invasion was measured, along with the impact of overexpressing miR-373 on the expression of p53 and PI3K/AKT pathway-related proteins. We found that miR-373 was specifically upregulated in spinal OS tissues (p < 0.01) and OS cell lines (p < 0.01 or p < 0.001). Moreover, miR-373 expression was significantly associated with TNM stage (p = 0.035) and tumor size (p = 0.002). Overexpression of miR-373 promoted MG-63 cell viability, migration, invasion, and colony formation (all p < 0.05), while silencing of miR-373 and LY294002 exerted the opposite effects. Additionally, miR-373 overexpression downregulated p53 as well as its downstream targeted genes and orderly activated the PI3K/AKT-Rac1-JNK signaling pathway. In conclusion, miR-373 promotes growth and cellular invasion in OS cells by activating the PI3K/AKT-Rac1-JNK pathway. Therefore, miR-373 might be a candidate for molecular targeted therapy of spinal OS.

miR-125b and miR-100 Are Predictive Biomarkers of Response to Induction Chemotherapy in Osteosarcoma

Osteosarcoma is the most common primary malignancy in bone. Patients who respond poorly to induction chemotherapy are at higher risk of adverse prognosis. The molecular basis for such poor prognosis remains unclear. We investigated miRNA expression in eight open biopsy samples to identify miRNAs predictive of response to induction chemotherapy and thus maybe used for risk stratification therapy. The samples were obtained from four patients with inferior necrosis (Huvos I/II) and four patients with superior necrosis (Huvos III/IV) following induction chemotherapy. We found six miRNAs, including miR-125b and miR-100, that were differentially expressed > 2-fold (p < 0.05) in patients who respond poorly to treatment. The association between poor prognosis and the abundance of miR-125b and miR-100 was confirmed by quantitative reverse transcriptase-polymerase chain reaction in 20 additional osteosarcoma patients. Accordingly, overexpression of miR-125b and miR-100 in three osteosarcoma cell lines enhanced cell proliferation, invasiveness, and resistance to chemotherapeutic drugs such as methotrexate, doxorubicin, and cisplatin. In addition, overexpression of miR-125b blocked the ability of these chemotherapy agents to induce apoptosis. As open biopsy is routinely performed to diagnose osteosarcoma, levels of miR-125b and miR-100 in these samples may be used as basis for risk stratification therapy.

miR-200c and phospho-AKT as prognostic factors and mediators of osteosarcoma progression and lung metastasis

Lung metastasis is the major cause of death in osteosarcoma patients. However, molecular mechanisms underlying this metastasis remain poorly understood. To identify key molecules related with pulmonary metastasis of pediatric osteosarcomas, we analyzed high-throughput miRNA expression in a cohort of 11 primary tumors and 15 lung metastases. Results were further validated with an independent cohort of 10 primary tumors and 6 metastases. In parallel, we performed immunohistochemical analysis of activated signaling pathways in 36 primary osteosarcomas. Only phospho-AKT associated with lower overall survival in primary tumors, supporting its role in osteosarcoma progression. CTNNB1 expression also associated with lower overall survival but was not strong enough to be considered an independent variable. Interestingly, miR-200c was overexpressed in lung metastases, implicating an inhibitory feed-back loop to PI3K-AKT. Moreover, transfection of miR200c-mimic in U2-OS cells reduced phospho-AKT levels but increased cellular migration and proliferation. Notably, miR-200c expression strongly correlated with miR-141 and with the osteogenic inhibitor miR-375, all implicated in epithelial to mesenchymal transition. These findings contrast epithelial tumors where reduced miR-200c expression promotes metastasis. Indeed, we noted that osteosarcoma cells in the lung also expressed the epithelial marker CDH1, revealing a change in their mesenchymal phenotype. We propose that miR-200c upregulation occurs late in osteosarcoma progression to provide cells with an epithelial phenotype that facilitates their integration in the metastatic lung niche. Thus, our findings identify phospho-AKT in the primary tumor and miR-200c later during tumor progression as prognostic molecules and potential therapeutic targets to prevent progression and metastasis of pediatric osteosarcomas.