LINC01128 regulates the development of osteosarcoma by sponging miR-299-3p to mediate MMP2 expression and activating Wnt/β-catenin signalling pathway.

Osteosarcoma (OS) is one of the most common metastatic bone cancers, which results in significant morbidity and mortality. The important role of long non-coding RNAs (lncRNAs) in the biological processes of OS has been demonstrated through several studies. In the current study, we evaluated the role of the lncRNA, LINC01128, in OS. We analysed the expression of LINC01128 in three OS gene expression omnibus (GEO) data sets GSE21257, GSE36001 and GSE42352. The expression of LINC01128 in OS tissues and matched non-tumour tissues obtained from 50 OS patients was detected using qRT-PCR. The association between LINC01128 expression and overall survival of OS patients was evaluated using the Kaplan-Meier method. The effects of LINC01128 knockdown and overexpression were evaluated through in vitro and in vivo assays. The LINC01128/miR-299-3p/ MMP2 axis was verified using dual-luciferase reporter assay and qRT-PCR assays. GEO data sets analysis revealed that the expression of LINC01128 was increased in OS. Elevated LINC01128 expression was accompanied by shorter overall survival in OS patients. Functional studies revealed that LINC01128 knockdown reduced the proliferation, migration and invasion of OS cells both in vitro and in vivo. Mechanistically, LINC01128 sponged miR-299-3p to increase MMP2 expression. Rescue assays determined the role of the LINC01128/miR-299-3p/MMP2 axis in the proliferation, migration and invasion of OS cells. Additionally, the Wnt/β-catenin signalling pathway was activated by LINC01128 and MMP2 in OS cell lines. In summary, this study demonstrates that LINC01128 facilitates OS by functioning as a sponge of miR-299-3p, thus promoting MMP2 expression and activating the Wnt/β-catenin signalling pathway.

Yao Q ，Chen T 《-》

LncRNA AWPPH promotes osteosarcoma progression via activation of Wnt/β-catenin pathway through modulating miR-93-3p/FZD7 axis.

Long noncoding RNAs (lncRNAs) have important regulatory roles in osteosarcoma (OS) progression. Recent researches have shown lncRNA AWPPH promotes lung cancer progression and bladder cancer development. Yet, the function of AWPPH in OS is unknown. In this research, results indicated AWPPH levels were increased in OS tissues in contrast to paracancerous controls. Up-regulated AWPPH was associated with advanced stage, tumor size and metastasis. Besides, AWPPH up-regulation indicated a low survival rate in OS patients. Silencing of AWPPH suppressed proliferation, migration and invasion of OS cells. Mechanistically, AWPPH was demonstrated to sponge miR-93-3p and promote FZD7 expression, causing activation of Wnt/β-catenin. Inhibition of miR-93-3p effectively reversed the effects of AWPPH knockdown on OS cells. Collectively, our findings suggested AWPPH may be a prognostic biomarker and potential therapeutic target. AWPPH enhances FZD7-mediated activation of Wnt/β-catenin by sponging miR-93-3p to promote OS progression.

Li C ，Wang F ，Wei B ，Wang L ，Kong D ... -  《-》

microRNA-377-3p inhibits osteosarcoma progression by targeting CUL1 and regulating Wnt/β-catenin signaling pathway.

Emerging studies highlight the crucial effects of microRNAs on cancer initiation and malignant progression of various tumors. This study focused on the biological effect of miR-377-3p on CUL1 and epithelial-mesenchymal transition (EMT) and Wnt/β-catenin pathways in osteosarcoma (OS). We performed quantitative real-time polymerase chain reaction (qRT-PCR) to analyze miR-377-3p and CUL1 expression levels in OS tissues and MG-63 cells. Then, cell counting kit (CCK)-8 and Transwell assay were used to examine the functions of miR-377-3p in OS cell growth and metastasis abilities. Meanwhile, luciferase reporter assay was used to validate CUL1 as direct target of miR-377-3p. qRT-PCR and Western blot were then carried out to detect the impact of miR-377-3p on EMT and Wnt/β-catenin pathways. Tumor xenograft models were established to further examine the effects of miR-377-3p on OS tumorigenesis in vivo. miR-377-3p downregulation was frequently identified in OS tissues and cells, which was associated with worse prognosis of OS patients. Functional experiments showed miR-377-3p restoration could dramatically repress OS cell growth and migration by regulation of EMT and Wnt/β-catenin pathways. Moreover, luciferase reporter assay revealed that CUL1 acted as a functional target of miR-377-3p. Additionally, the elevated CUL1 expressions in OS tissues also indicated poor prognosis of OS patients. Furthermore, the OS tumor growth was also obviously inhibited by miR-377-3p overexpression in vivo. Collectively, all the above findings revealed that miR-377-3p exerted anti-OS functions via CUL1 and EMT and Wnt/β-catenin pathways. These results may contribute to the development of clinical OS treatment.

Liang K ，Liao L ，Liu Q ，Ouyang Q ，Jia L ，Wu G ... -  《-》

miR-485-3p regulated by MALAT1 inhibits osteosarcoma glycolysis and metastasis by directly suppressing c-MET and AKT3/mTOR signalling.

Osteosarcoma (OS) is an extremely malignant bone cancer with high incidence and rapid progression. This study aims to investigate the role and underlying mechanisms of MALAT1 and miR-485-3p in OS. qRT-PCR and Western blotting were utilized to measure the levels of miR-485-3p, MALAT1, c-MET, AKT3, p-mTOR, mTOR, glycolysis-related proteins or migration-related proteins. Colony formation and transwell assay were used to test the roles of miR-485-3p, MALAT1, c-MET and AKT3 in cancer cell proliferation, migration and invasion. Dual luciferase assay was used to validate the interactions of miR-485-3p/c-MET, miR-485-3p/AKT3, and MALAT1/miR-485-3p. Glucose uptake assay and measurement of lactate production were employed to determine the glycolysis process. Mouse tumour xenograft model was used to determine the effect of shMALAT1 and miR-485-3p mimics on tumour growth and metastasis in vivo. miR-485-3p was decreased while c-MET, AKT3, and MALAT1 were increased in human OS tissues and cells. miR-485-3p bound directly to c-MET and AKT3 mRNAs and repressed OS cell glycolysis, proliferation, migration, and invasion through decreasing glycolysis-related proteins and migration-related proteins via inhibiting c-MET and AKT3/mTOR pathway. In addition, MALAT1 interacted with miR-485-3p and disinhibited c-MET and AKT3/mTOR signalling. Knockdown MALAT1 or overexpression of miR-485-3p restrained OS tumour growth and lung metastasis in vivo. miR-485-3p suppresses OS glycolysis, proliferation, and metastasis via inhibiting c-MET and AKT3/mTOR signalling and MALAT1 acts as a sponge of miR-485-3p. MALAT1 and miR-485-3p may be the key regulators in OS progression, and potential molecular targets for future OS therapy.

Wang Q ，Liu MJ ，Bu J ，Deng JL ，Jiang BY ，Jiang LD ，He XJ ... -  《-》

LncRNA ODRUL regulates progression of osteosarcoma by regulating IL-6 via sponging miR-6874-3p.

Accumulating evidence has shown that many long non-coding RNAs (lncRNA) participate in the tumorigenesis, including osteosarcoma (OS). Of them, lncRNA ODRUL was previously reported to act as a possible oncogene in OS doxorubicin resistance. However, the underlying molecular mechanism of ODRUL involved in the progression of OS still remains to be thoroughly investigated. In the current study, we reported another mechanism by which ODRUL regulates OS progression. QRT-PCR and WB were conducted to detect ODRUL, miR-6874-3p and IL-6 expression in OS tissues and cells. The Kaplan-Meier was used to assess the relevance between the expression level of miR-6874-3p and the overall survival of OS patients. Wound healing assays and Transwell assays were used to evaluate the invasion and migration of OS cells. Furthermore, the binding sites of ODRUL and IL-6 to miR-6874-3p were predicted by bioinformatics and verified by dual-luciferase reporter gene assays. ODRUL and IL-6 were highly expressed in OS cells and tissues, while miR-6874-3p was expressed at low levels. The overall survival of high miR-6874-3p expression of OS patients was longer than that of low miR-6874-3p expression of OS patients. MiR-6874-3p overexpression markedly inhibited the progression of OS cells. Both ODRUL and IL-6 could bind to miR-6874-3p at the predicted binding sites which were authenticated by dual-luciferase reporter gene assay. MiR-6874-3p could inhibit OS cell proliferation and metastasis and ODRUL could reverse the suppression induced by miR-6874-3p in vivo. In conclusion, ODRUL could effectively sponge miR-6874-3p to upregulate the expression of IL-6 in OS progression.

Zhan T ，Zhu K ，Hu J ，Ma X ，Zhu Y ，Zhang C ... -  《-》