Integrated bioinformatics analysis of miRNA expression in osteosarcoma

Melatonin Increases the Sensitivity of Osteosarcoma Cells to Chemotherapy Drug Cisplatin

Chemotherapy, which is one of the common treatments for osteosarcoma (OS), has many side effects and in some cases has low effectiveness due to chemoresistance, hence it is vital to study new therapies for OS. In this regard, we combined melatonin with cisplatin and evaluate their effect on MG63 OS cells. Since melatonin has anti-cancer properties, we hypothesized that its combination with cisplatin could increase the effectiveness of cisplatin. Firstly, MTT assay was used to evaluate the cell viability and cytotoxicity of cisplatin on MG63 cells and the results showed that melatonin in combination with cisplatin increases the sensitivity of MG63 cells to cisplatin. In addition, qRT-PCR results showed that the expressions of miR-181 and P53, CYLD, CBX7 and BCL2 genes change in MG63 cells after treatment with the combination of cisplatin and melatonin, so that the expression of P53, CYLD and CBX7 increased and the expression of BCL2 and miR-181b decreases significantly. Furthermore, analysis of Annexin V/FITC assay data revealed that the rate of apoptosis in MG63 OS cell line remarkably promoted after treated with cisplatin and melatonin combination. As a result, our findings show that melatonin in combination with cisplatin increases the effectiveness of cisplatin in osteosarcoma cells and this study provides a new therapeutic approach for OS.

The Emerging Role of MicroRNAs in Bone Diseases and Their Therapeutic Potential

MicroRNAs (miRNAs) are a class of small (20-24 nucleotides), highly conserved, non-coding RNA molecules whose main function is the post-transcriptional regulation of gene expression through sequence-specific manners, such as mRNA degradation or translational repression. Since these key regulatory molecules are implicated in several biological processes, their altered expression affects the preservation of cellular homeostasis and leads to the development of a wide range of pathologies. Over the last few years, relevant investigations have elucidated that miRNAs participate in different stages of bone growth and development. Moreover, the abnormal expression of these RNA molecules in bone cells and tissues has been significantly associated with the progression of numerous bone diseases, including osteoporosis, osteosarcoma, osteonecrosis and bone metastasis, among others. In fact, miRNAs regulate multiple pathological mechanisms, including altering either osteogenic or osteoblast differentiation, metastasis, osteosarcoma cell proliferation, and bone loss. Therefore, in this present review, aiming to impulse the research arena of the biological implications of miRNA transcriptome in bone diseases and to explore their potentiality as a theragnostic target, we summarize the recent findings associated with the clinical significance of miRNAs in these ailments.

Bioinformatic Analysis Identified Potentially Prognostic Long Noncoding RNAs and MicroRNAs for Gastric Cancer

Gastric cancer (GC) is the fifth most common malignant tumor in the world. The present study was performed to discover the potential diagnostic and therapeutic long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) of GC. Data used in this study to identify differentially expressed lncRNAs (DElncRNAs) and miRNAs (DEmiRNAs) were obtained from 187 GC tissues and 32 adjacent nontumor tissues. The total clinical data on GC included 187 cases. The above data were from the TCGA database. RStudio/Bioconductor software was used to conduct univariate analysis, the least absolute shrinkage and selection operator (LASSO) Cox, and multivariate Cox proportional risk regression for the DElncRNAs and DEmiRNAs. Clinical information was analyzed through univariate and multivariate Cox analysis. Results: five lncRNAs (AC007785.3, AC079385.3, LINC00392, LINC01729, and U95743.1) and two miRNAs (hsa-miR-3174, hsa-miR-605) were proven to be independent prognostic indicators of GC. Results of the Kaplan-Meier survival analysis showed that AC007785.3, AC079385.3, LINC01729, miR-3174, and miR-605 were significantly correlated with OS of GC. The target genes of AC079385.3, miR-3174, and miR-605 were obtained and clustered mainly on MAPK and cGMP-PKG signaling pathways. The clinical data showed that age and clinicopathologic stage were correlated with the prognosis of GC. Furthermore, AC007785.3 was associated with metastasis of GC, and miR-3174 was associated with the primary tumor condition of GC. We identified three lncRNAs (AC007785.3, AC079385.3, LINC01729), two miRNAs (miR-3174, miR-605), and clinical factors related to the pathogenesis and prognosis of GC. Our predicted results provide a possible entry point for the study of prognostic markers for GC.

A Novel Predictive Model Associated with Osteosarcoma Metastasis

Purpose

Long non-coding RNAs (lncRNAs) have diverse roles in modulating gene expression on both transcriptional and translational levels, but their involvement in osteosarcoma (OS) metastasis remains unknown.

Patients and Methods

Transcriptional and clinical data were downloaded from TARGET datasets. A total of seven lncRNAs screened by univariate cox regression, lasso regression, and multivariate cox regression analysis were used to establish the OS metastasis model. The area under the receiver operating characteristic curve (AUC) was used to evaluate the model.

Results

The established model showed exceptional predictive performance (1 year: AUC = 0.92, 95% Cl = 0.83-0.99; 3 years: AUC = 0.87, 95% Cl = 0.79-0.96; 5 years: AUC = 0.86, 95% Cl = 0.76-0.96). Patients in the high group had a poor survival outcome than those in the low group (p < 0.0001). GSEA analysis revealed that "NOTCH_SIGNALING" and "WNT_BETA_CATENIN_SIGNALING" were significantly enriched and that resting dendritic cells were associated with AL512422.1, AL357507.1, and AC006033.2 (p < 0.05).

Conclusion

Based on seven prognosis-related lncRNAs, we constructed a novel model with high reliability and accuracy for predicting metastasis in OS patients.

Osteosarcoma Cell-Derived Small Extracellular Vesicles Enhance Osteoclastogenesis and Bone Resorption Through Transferring MicroRNA-19a-3p

Osteosarcoma (OS) is the most common primary bone cancer characterized by an aggressive phenotype with bone destruction. The prognosis of OS patients remains unoptimistic with the current treatment strategy. Recently, osteoclasts are believed to play a crucial role in cancer bone metastasis. Thus, osteoclast could be a target both in bone destruction and cancer progression in OS. However, mechanisms governing osteoclastogenesis in OS remain poorly understood. miRNA delivered by small extracellular vesicles (sEVs) could mediate cellular communications. In this study, we investigated the effects of sEVs on osteoclastogenesis and osteoclast function, also clarified the underlying mechanism. We herein found that sEVs promoted pre-osteoclast migration, osteoclastogenesis and resorption by exposing RAW264.7 cells to sEVs derived from OS cells. Bioinformatics analysis showed that phosphatase tension homologue (PTEN), and miR-19a-3p were involved in OS progression. Overexpression of miR-19a-3p or sEVs’ miR-19a-3p promoted osteoclast formation and function through PTEN/PI3K/AKT signaling pathway, while inhibition of miR-19a-3p showed the contrary results. The bone marrow macrophages (BMMs) were used to verify the results. OS mice, which were established by subcutaneous injection of OS cells, exhibited increased levels of sEVs’ miR-19a-3p in blood. Moreover, micro-computed tomography (CT) and histomorphometry analysis demonstrated that OS mice exhibited osteopenia with increased number of osteoclasts. In conclusion, miR-19a-3p delivery via OS cell-derived sEVs promotes osteoclast differentiation and bone destruction through PTEN/phosphatidylinositol 3 -kinase (PI3K)/protein kinase B (AKT) signaling pathway. These findings highlight sEVs packaging of miR-19a-3p as a potential target for prevention and treatment of bone destruction and cancer progression in OS patients. And this finding provides a novel potentially therapeutic target for the bone metastasis.

The Target MicroRNAs and Potential Underlying Mechanisms of Yiqi-Bushen-Tiaozhi Recipe against-Non-Alcoholic Steatohepatitis

MicroRNAs (miRNAs) have emerged as potential therapeutic targets for non-alcoholic fatty liver disease/non-alcoholic steatohepatitis (NAFLD/NASH). Traditional Chineses Medicine (TCM) plays an important role in the prevention or treatment of NAFLD/NASH. However, miRNA targets of TCM against NASH still remain largely unknown. Here, we showed that Yiqi-Bushen-Tiaozhi (YBT) recipe effectively attenuated diet-induced NASH in C57BL/6 mice. To identify the miRNA targets of YBT and understand the potential underlying mechanisms, we performed network pharmacology using miRNA and mRNA deep sequencing data combined with Ingenuity Pathway Analysis (IPA). Mmu-let-7a-5p, mmu-let-7b-5p, mmu-let-7g-3p and mmu-miR-106b-3p were screened as the main targets of YBT. Our results suggested that YBT might alleviate NASH by regulating the expression of these miRNAs that potentially modulate inflammation/immunity and oxidative stress. This study provides useful information for guiding future studies on the mechanism of YBT against NASH by regulating miRNAs.

Dysregulated microRNAs in laryngeal cancer: a comprehensive meta-analysis using a robust rank aggregation approach

We need a reasonable method of compiling data from different studies regarding the expression of microRNA (miRNA) in laryngeal squamous cell carcinoma (LSCC). The robust rank aggregation method was used to integrate the rank lists of miRNAs from 11 studies. The enrichment analysis was performed on target genes of meta-signature miRNAs. The Cancer Genome Atlas database was used to confirm the results of meta-analysis. Three meta-signature miRNAs (miR-21-5p, miR-196a-5p and miR-145-5p) were obtained. All three miRNAs could be prognostic for LSCC. The enrichment analysis showed that these miRNAs were associated significantly with multiple cancer-related signaling pathways. The robust rank aggregation approach is an effective way to identify important miRNAs from different studies. All identified miRNAs could be candidates for LSCC diagnostic and prognostic biomarkers.

Circular RNA hsa_circ_0002052 promotes osteosarcoma via modulating miR-382/STX6 axis

Circular RNAs (circRNAs) exert pivotal effects on regulating the progression of osteosarcoma (OS). It was found through microarray analysis that circ-0002052 is abnormally expressed in OS, but the role of circ-0002052 in OS remains obscure. The results of this research manifested that relative to that in non-tumor controls, circ-0002052 level was raised in OS tissues. Up-regulated circ-0002052 was associated with advanced stage, tumor size, and metastasis. Additionally, circ-0002052 elevation indicated a low survival rate in OS patients and silencing of circ-0002052 suppressed proliferation, migration, and invasion of OS cells. It was proved that circ-0002052 sponged miR-382 and stimulated STX6 expression, thus activating Wnt/β-catenin. The function of circ-0002052 reduction in OS cells was effectively reversed by miR-382 suppression. To sum up, it can be concluded that circ-0002052, functioning as a sponge for miR-382, enhances the activation of Wnt/β-catenin mediated by STX6 to stimulate the progression of OS, and circ-0002052 may be an underlying treatment target and a biomarker for prognosis of osteosarcoma.

Elevated Expression of miR-629 Predicts a Poor Prognosis and Promotes Cell Proliferation, Migration, and Invasion of Osteosarcoma

Purpose

Osteosarcoma (OS) is an invasive bone tumor that primarily affects children and adolescents. MicroRNA-629 (miR-629) acts as an oncogene involved in the development of various cancers. This study aims to reveal the clinical significance and biological function of miR-629 in OS.

Patients and Methods

The levels of miR-629 expression in tissues and cells were detected through quantitative real-time polymerase chain reaction (qRT-PCR). Chi-square test was used to evaluate the relationship between miR-621 expression and clinical parameters in patients with OS. Survival analysis was performed by the Kaplan-Meier method. Cox regression analysis of the effect of miR-629 expression on the prognosis of OS patients. CCK-8 and Transwell experiments were used to demonstrate the effect of miR-629 on OS cell function.

Results

Compared with the controls, miR-629 levels were significantly elevated in patients with OS (P < 0.001), Furthermore, miR-629 upregulation showed significantly associated with clinical stage (P = 0.011), distant metastasis (P = 0.003) and poor survival (log rank test, P = 0.013) in OS patients. miR-629 might be a potential prognostic biomarker for OS (HR = 2.890, 95% CI = 1.126-7.416, P = 0.027). Cell function experiments proved that the high expression of miR-629 promoted cell proliferation, migration, and invasion of OS.

Conclusion

All experimental results demonstrated that miR-629 as an oncogene promotes the tumor cell growth, migration and invasion of OS, and miR-629 may act as a novel prognostic biomarker and therapeutic target for patients with this malignant tumor.

miR-451a Inhibits the Growth and Invasion of Osteosarcoma via Targeting TRIM66

The importance of microRNAs in regulating osteosarcoma development has been studied in recent years. However, the function of microRNA-451a in osteosarcoma growth is rarely investigated. Here, we explored the expression of microRNA-451a in osteosarcoma cell lines. Bioinformatic software, luciferase activity reporter assay, and Western blot were conducted to determine the association between microRNA-451a and tripartite motif-containing 66. Cell Counting Kit-8 assay and transwell assay were used to explore the regulatory effects of microRNA-451a on osteosarcoma cells. Moreover, we explored whether microRNA-451a modulates osteosarcoma cell biological activity by regulating tripartite motif-containing 66. The expression of microRNA-451a was found to be downregulated in osteosarcoma and negatively regulated the expression of tripartite motif-containing 66. Tripartite motif-containing 66 was further validated as a target of microRNA-451a. MicroRNA-451a inhibits the growth and invasion of osteosarcoma cell lines through targeting tripartite motif-containing 66. The miR-451a targets tripartite motif-containing 66 may provide novel therapeutic targets for the treatment of osteosarcoma.

Extracellular nanovesicles-transmitted circular RNA has_circ_0000190 suppresses osteosarcoma progression

Under the microenvironment, tumour progression is substantially affected by cell-cell communication. In spite of the mediating effect of extracellular nanovesicles (EVs) on cell-cell communication by packaging into circRNAs, the effect of EVs circRNA hsa_circ_0000190 (circ-0000190) in osteosarcoma is still not clear. Circ-0000190 expressions in tissues and EVs from plasma were compared between osteosarcoma patients and controls. Thereafter, receiver operating characteristic (ROC) curve was drawn and area under the curve was calculated to examine whether the diagnostic results were accurate, and the effect of EVs circ-0000190 was dug out via the determination of cell phenotypes and animal assays. Results showed circ-0000190 exhibited an obvious reduction in EVs and tissues of osteosarcoma patients (P < .05). It was also discovered that EVs encapsulated the majority of circ-0000190, and EVs-encapsulated circ-0000190 could be applied to make a distinction between osteosarcoma patients and controls. Besides, EVs circ-0000190 in osteosarcoma cells transported from normal cells weakened the capacities of osteosarcoma cells to migrate, proliferate and invade, so as to block their biological malignant behaviours (P < .05). In addition, under the action of EVs circ-0000190, tumour growth was impeded and the expression of TET1 was inhibited via the competitive binding to miR-767-5p. In all, EVs circ-0000190 has a good prospect as it can be regarded as a new biomarker for detecting osteosarcoma. EVs circ-0000190 transported from normal cells to osteosarcoma cells impeded the in vitro and in vivo development of osteosarcoma, implying that EVs circ-0000190 exerts an effect on communication between normal cells and osteosarcoma cells in the carcinogenesis process of osteosarcoma.

MiR-421 promotes the development of osteosarcoma by regulating MCPIP1 expression

Despite improvements in surgical resection and adjuvant chemotherapy, the prognosis and outcomes of patients with osteosarcoma remains poor due to the occurrence of metastasis or relapse. Monocyte chemoattractant protein-1-induced protein-1 (MCPIP1), a zinc-finger RNA-binding protein, is known to regulate inflammatory responses and repress breast cancer growth. However, the regulation of MCPIP1 by microRNAs has not been clearly elucidated in osteosarcoma. In this study, we found that miR-421 expression was upregulated and MCPIP1 expression was downregulated in the osteosarcoma specimens from patients. Moreover, MCPIP1 expression was inversely correlated with miR-421 expression in the clinical samples. Furthermore, the upregulation of miR-421 and downregulation of MCPIP1 resulted in poor overall survival and severe disease progression, respectively, in the patients with osteosarcoma. Bioinformatics analysis and luciferase reporter gene assays confirmed that miR-421 specifically targets and binds to the 3'-UTR of MCPIP1. The overexpression of miR-421 induced cell proliferation, invasion, and migration, and the release of pro-inflammatory IL-6 in cultured human osteosarcoma cells. Additionally, the administration of miR-421 to tumor-bearing mice facilitated osteosarcoma growth by downregulating MCPIP1 expression. Taken together, these findings indicate that miR-421 is able to promote the development of osteosarcoma by regulating MCPIP1 expression, and can be a potential therapeutic target for osteosarcoma.

MicroRNA-506-3p inhibits osteosarcoma cell proliferation and metastasis by suppressing RAB3D expression

Osteosarcoma is an aggressive bone tumor primarily affecting children and adolescents. Its cause is not yet fully understood, and there is an urgent need for more effective treatment. In the present study we identified several miRNAs whose expression is altered in osteosarcoma compared to adjacent normal tissue. Moreover, expression levels of one of those miRNAs, miR-506-3p, correlated negatively with expression of RAB3D (a Ras-related protein). Suppression of miR-506-3p in osteosarcoma led to increased expression of RAB3D, which in turn led to increased CDK4 (cyclin-dependent kinase 4) and MMP9 (matrix metalloprotein 9) activities. Our results suggest that miR-506-3p acts as a tumor suppressor in osteosarcoma and that its downregulation leads to tumor cell proliferation and metastasis due to upregulation of RAB3D- and CDK4-mediated signaling. miR-506-3p thus appears be a potentially useful target for adjuvant therapy in osteosarcoma patients.

miR-627-3p inhibits osteosarcoma cell proliferation and metastasis by targeting PTN

Dysregulation of microRNA (miRNA) has been observed in several types of tumors, including osteosarcoma. Biochip analysis was used to identify miRNAs differentially expressed in osteosarcoma tissues. The targeting sites of miR-627-3p were analyzed using miRDB software and fluorescein reporter gene. MTT and Transwell assays were used to analyze the effects of miR-627-3p on the growth and migration of osteosarcoma cells. Western blotting and real-time PCR were used to detect the effects of miR-627-3p on related proteins. In vivo experiments were conducted to verify the effect of miR-627-3p on osteosarcoma. We focused on miR-627-3p because it was the most significantly downregulated miRNA in our screening study. Through luciferase reporter assays, western blotting and real-time PCR we found that miR-627-3p directly targets PTN, and that expression levels of miR-627-3p and PTN are negatively correlated in osteosarcoma cells. Downregulation of miR-627-3p promoted osteosarcoma cell proliferation and metastasis, while its overexpression had the opposite effect. By targeting PTN, miR-627-3p also suppressed expression of Cyclin D1 and MMP2. MiR-627-3p inhibited osteosarcoma metastasis in vivo. Thus, miR-627-3p may be a useful therapeutic target for the treatment osteosarcoma or prevention of metastasis.

MiR-30a-5p frequently downregulated in prostate cancer inhibits cell proliferation via targeting PCLAF

MicroRNAs (miRNAs) have vastly expanded our view of RNA world in intracellular signal regulating networks. Here, we functionally characterized a normally highly expressed miRNA, miR-30a-5p (MIMAT0000087), which exhibits downregulated expression profiles in prostate cancer samples. MiR-30a-5p knockdown and overexpression in PC-3 cell line alters cell proliferation supporting a tumour suppressor role. We also discovered that PCLAF is the direct target of miR-30a-5p. Notably, PC-3 cell proliferation is inhibited by miR-30a-5p/PCLAF axis. miR-30a-5p represents a novel molecule of functionally important miRNAs which may shed light on the novel therapeutic targets for prostate cancer.

RETRACTED: miR-27b Targets HOXB8 to Inhibit Malignant Behaviors of Osteosarcoma

MicroRNAs function as either tumor suppressor or oncogene in human cancers. This study aimed to explore the role of miR-27b in osteosarcoma. Expression of miR-27b or homeobox B8 in osteosarcoma cell lines was analyzed by quantitative real-time polymerase chain reaction and Western blot, respectively. Luciferase activity reporter assay and Western blot were conducted to explore the association between miR-27b and homeobox B8. Cell Counting Kit-8, colony formation assay, and wound-healing assay were performed to investigate the role of miR-27b or homeobox B8 on cell proliferation, colony formation, and cell migration. Expression of miR-27b was significantly reduced, while homeobox B8 was increased in osteosarcoma cell lines. In addition, homeobox B8 was validated as a direct target of homeobox B8. Moreover, miR-27b regulates osteosarcoma cell proliferation, colony formation, and migration through targeting homeobox B8. Taken together, our study provides novel insight into the progression of osteosarcoma, and the miR-27b–homeobox B8 axis identified may be developed as therapeutic targets against hepatocellular carcinoma in the future.

Bioinformatics prediction of miR-30a targets and its inhibition of cell proliferation of osteosarcoma by up-regulating the expression of PTEN

BACKGROUND

MiRNAs are frequently abnormally expressed in the progression of human osteosarcoma. Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) is one of the tumor suppressors in various types of human cancer. In the present study, we detected how hsa-miR-30a-3p regulated PTEN and further tested the role of hsa-miR-30a-3p in the cell proliferation of osteosarcoma cells.

METHODS

The levels of miR-30a were determined by real time PCR. The expression of PTEN was tested by western blotting analysis. Cell distribution of PTEN was observed with confocal laser scanning microscope. Cell viability was determined by MTT assay.

RESULTS

The expression of miR-30a and PTEN was obviously decreased in MG-63, 143B and Saos-2 cells compared with primary osteoblasts. TargetScan analysis data showed miR-30a might bind with position 30-57 of 3'UTR of PTEN. Transfection with miR-30a-3p increased the level of PTEN in MG-63 cells, while transfection with miR-30a-3p inhibitor significantly decreased the expression of PTEN in osteosarcoma cells. Transfection with miR-30a-3p significantly inhibited cell proliferation of osteosarcoma cells, while miR-30a inhibitor obviously promoted cell viability of MG63 cells and Saos-2 cells. Inhibition of PTEN eliminated the proliferation inhibitory effect of miR-30a-3p.

CONCLUSION

Thus, all these findings revealed the anti-tumor effects of miR-30a in human osteosarcoma cells, which could be mediated by regulating the level of PTEN.

MiR-199a targeting ROCK1 to affect kidney cell proliferation, invasion and apoptosis

Renal cell carcinoma (RCC) is one of the three most common cancers of urinary tract cancer, accounting for 2-3% of all systemic cancers. Recent studies have found that miR-199a is lowly expressed in RCC, may act as a tumour suppressor gene to induce the occurrence of kidney cancer. In the present study, we investigated the role of miR-199a in the progression and metastasis of RCC. The results showed that miR-199a significantly downregulated in RCC and cell lines. Overexpression of miR-199a in RCC cell lines significantly inhibited cell proliferation, migration and invasion. Furthermore, the qRT-PCR and western blot results showed that miR-199a overexpression significantly downregulated ROCK-1 mRNA and protein levels. ROCK1 was identified as a target of miR-199a, and ectopic expression of miR-199a downregulated ROCK1 by direct binding to its 3' untranslated region. Together, these findings indicate that miR-199a acts as a tumour suppressor and its downregulation in tumour tissues may contribute to the progression and metastasis of RCC through a mechanism involving ROCK1, suggesting miR-199a as a potential new diagnostic and therapeutic target for the treatment of RCC.

Silencing of BACH1 inhibits invasion and migration of prostate cancer cells by altering metastasis-related gene expression

BACKGROUND

Cancer lethality is mainly caused by metastasis. Therefore, understanding the nature of the genes involved in this process has become a priority. BACH1, a basic leucine zipper transcription factor, has been shown to transcriptionally regulate expression of a range of genes that are associated with breast cancer metastasis. However, the exact role and the underlying molecular mechanism of BACH1 in prostate cancer remain unclear. This study aims to explore the expression of BACH1 in prostate cancer tissues and the effect of BACH1 suppression on prostate cancer cell behavior.

MATERIALS AND METHODS

In this study, we used quantitative real-time PCR (qRT-PCR) to measure BACH1 expression in prostate adenocarcinoma tissues and two metastasis-derived prostate cancer cell lines, DU145 and LNCaP. We also used immunohistochemical (IHC) staining to measure BACH1 protein expression in prostate adenocarcinoma and matched normal tissue samples. In the following BACH1 expression was silenced in DU145 cells using siRNA as well. Knockdown was confirmed by qRT-PCR and Western blotting. The cytotoxic effects of BACH1-siRNA on DU145 cells were determined using an MTT assay. The migration and invasive capacity of DU145 cells were examined by scratch wound healing assay and matrigel invasion assay, respectively. We also used qRT-PCR to study the effect of BACH1 silencing on the expression levels of metastasis-related genes.

RESULTS

We find that the expression of BACH1 mRNA and protein in prostate cancer tissues is significantly higher than in matched normal prostate tissues (p < .05). In addition, DU145 and LNCaP cells exhibited 4.25-fold and 3.45-fold higher levels of BACH1 compared to HFF cell line. BACH1-siRNA significantly reduced both mRNA and protein expression levels in DU145 cells. More importantly, we show that BACH1 promotes key features of metastasis, as BACH1-siRNA treatment significantly reduced cell invasion and migration by changing the expression levels of a number of metastasis-related genes in vitro.

CONCLUSIONS

BACH1 is overexpressed in prostate cancer. Because this promotes invasion and migration, it may facilitate metastasis of prostate cancer. Thus, BACH1 is a potential therapeutic target for metastatic prostate cancer. BACH1 silencing therapy can be considered as a novel and effective adjuvant in prostate cancer targeted therapies.

USP17 is upregulated in osteosarcoma and promotes cell proliferation, metastasis, and epithelial–mesenchymal transition through stabilizing SMAD4

USP17 is upregulated in several cancers, indicating that USP17 might play essential functions in tumor development. However, the function of USP17 in osteosarcoma is still unknown. Our work aimed to investigate the function of USP17 in osteosarcoma. We found that the expression of USP17 was upregulated in osteosarcoma tissues and cell lines, including MG-63 and U2OS. Several functional experiments, such as colony formation analysis, Cell Counting Kit-8 assay, wound healing analysis, and transwell assay, showed that USP17 promoted cell proliferation, migration, and invasion. Moreover, we found that USP17 facilitated migration and invasion through promoting epithelial–mesenchymal transition. SMAD4 has been found to regulate epithelial–mesenchymal transition, co-immunopurification, and glutathione S-transferase pull-down analysis demonstrated that USP17 interacted with SMAD4. Furthermore, USP17 stabilized SMAD4 through its deubiquitinase activity. In conclusion, this study shows that USP17 enhances osteosarcoma cell proliferation and invasion through stabilizing SMAD4.

miR-486 suppresses the development of osteosarcoma by regulating PKC-δ pathway

Osteosarcoma is one of the most highly malignant types of cancer in adolescents and young adults with a high mortality rate. Despite advances in surgery, radiation therapy and chemotherapy, the prognosis for patients with osteosarcoma has not significantly improved over the past several decades. It is necessary to find new indicators of prognosis and therapeutic targets of osteosarcoma. Through the analysis of 40 osteosarcoma tissues, we found that the expression of miR‑486 was low and the expression of PKC‑δ was high in osteosarcoma. Median survival of patients with low expression of miR-486 (30 months) was shorter than the patients with higher expression of miR‑486 (40 months). We further found that miR-486 can inhibit the targeting of PKC‑δ signaling pathways, and this inhibition can inhibit the growth and invasion of osteosarcoma cells. After transfection of miR‑486 for 24 h, the proliferation of osteosarcoma cells was inhibited by ~20%, and the migration was inhibited by ~15%. In the present investigation, we demonstrated that miR‑486 is negatively associated with the expression of PKC-δ and could regulate the development of osteosarcoma. miR-486 may be a potential target for the treatment of osteosarcoma.