[Retracted] MicroRNA­505 is downregulated in human osteosarcoma and regulates cell proliferation, migration and invasion.

Following the publication of this paper, it was drawn to the Editor's attention by a concerned reader that the control GAPDH western blotting bands shown in Fig. 4H on p. 496 were strikingly similar to data that were submitted for publication in advance of this article in different form by different authors at different research institutes [Liu F, Bai C and Guo Z: The prognostic value of osteopontin in limited­stage small cell lung cancer patients and its mechanism. Oncotarget 8: 70084­70096, 2017]. A further independent investigation conducted in the Editorial Office revealed that other western blotting data were likely to have been shared in common, comparing between the two articles. Owing to the fact that the contentious data in the above article had already been submitted for publication prior to the submission of this article to Oncology Reports, the Editor has decided that this paper should be retracted from the Journal. After having been in contact with the authors, it was admitted that the authors Feng Chang, Jian-Na Liu and Jun-Xin Lin did not initially provide their agreement to be authors on this paper; otherwise, the rest of the authors accepted the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [Oncology Reports 39: 491­500, 2018; DOI: 10.3892/or.2017.6142].

MicroRNA-505 is downregulated in human osteosarcoma and regulates cell proliferation, migration and invasion.

Recent studies have demonstrated that microRNAs (miRNAs/miRs) are involved in osteosarcoma tumorigenesis, progression, invasion and metastasis. For example, miR-505 plays important roles in human carcinogenesis; however, its exact function in osteosarcoma remains unclear. MicroRNA profiles of osteosarcoma and normal tissues were obtained by miRNA microarray assays, which were validated by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). Then, high-mobility group box 1 (HMGB1) expression was evaluated by qRT-PCR and western blot analysis. The correlation between miR-505 and HMGB1 was analyzed by Pearson correlation. In vitro, the biological functions of miR-505 were examined by wound healing, MTT and Transwell assays and western blot analysis in MG63 cells transfected with miRNA mimics or empty vector. Luciferase assay was utilized to assess whether HMGB1 is a target of miR-505. miRNA microarrays revealed 26 aberrant miRNAs in osteosarcoma tissues; miR-505 showed the most pronounced decrease (P<0.01), which was significantly associated with TNM stage and metastasis status (P<0.05). In addition, HMGB1 was highly expressed in osteosarcoma tissues (P<0.01), with a significantly negative correlation with miR-505 (r=-0.6679, P<0.001). Furthermore, miR-505 inhibited proliferation, migration and invasion abilities of MG63 cells (P<0.01). Moreover, luciferase activity of the HMGB1-3'-UTR plasmid was suppressed following miR-505 binding (P<0.01). Finally, HMGB1 overexpression partly reversed the effects of miR-505 on MG63 cells. In conclusion, miR-505 levels are decreased in osteosarcoma tissues, and reduced miR-505 expression is significantly associated with poorer clinical prognosis in patients with osteosarcomas. miR-505 inhibits osteosarcoma cell proliferation, migration and invasion by regulating HMGB1.