Spontaneous Conventional Osteosarcoma Transformation of a Chondroblastoma: A Case Report and Literature Review

Long non-coding RNA BLACAT1 expedites osteosarcoma cell proliferation, migration and invasion via up-regulating SOX12 through miR-608

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BLACAT1 promotes cell proliferation, migration and invasion, and dampens cell apoptosis in OS.

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BLACAT1 sponges miR-608 in OS.

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SOX12 is the target of miR-608.

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BLACA1 promotes OS cell growth and migration via targeting miR-608/SOX12 axis.

Background

Osteosarcoma is the most common type of bone malignancy. Increasing evidence indicated that long non-coding RNAs (lncRNAs) possess multiple functions in the development of cancer and can be used as indicators of prognosis and diagnosis. LncRNA BLACAT1 has been found to promote the proliferation of breast cancer cells. However, the role of BLACAT1 in osteosarcoma remains largely unknown.

Methods

QRT-PCR analysis was employed to evaluate mRNA expressions. Western blot was performed to measure relevant protein level. Colony formation and EdU assays were conducted to certify proliferative ability. TUNEL assay was finalized to assess apoptotic cells. Wound-healing and transwell assays were utilized for the exploration of migrating and invasive abilities. The subcellular distribution of BLACAT1 was studied by nucleus-cytoplasm separation assay. Relevant mechanical experiments were combined to elucidate molecular relationship between molecules.

Results

BLACAT1 was highly expressed in osteosarcoma. BLACAT1 promoted the proliferation and migration of osteosarcoma cells. BLACAT1 acted as a sponge for miR-608 to augment the expression of Sex determining region Y-box protein 12 (SOX12), the direct target of miR-608. Further, inhibiting miR-608 recovered the repressive effect of silenced BLACAT1 on the malignant behaviors of osteosarcoma cells.

Conclusion

This study highlighted the contribution of BLACAT1/miR-608/SOX12 axis to the progression of osteosarcoma, suggesting novel targets for osteosarcoma therapy.

Positive feedback loop SP1/MIR17HG/miR-130a-3p promotes osteosarcoma proliferation and cisplatin resistance

Long noncoding RNAs (lncRNAs) have been identified to be critical regulator in the osteosarcoma (OS) tumorigenesis. However, the role of lncRNA MIR17HG in the OS proliferation and chemotherapy resistance is still unclear. Here, this research aims to investigate the function of lncRNA MIR17HG in the OS proliferation and cisplatin resistance. Clinically, results revealed that higher MIR17HG expression was associated with shorter overall survival. Functional investigations indicated that MIR17HG promoted the proliferation, invasion and cisplatin resistance of OS cells in vitro, and the MIR17HG knockdown inhibited the growth in vivo. Mechanistically, MIR17HG targeted the miR-130a-3p/SP1 axis, moreover, transcription factor SP1 bind with the MIR17HG promoter region to promote its expression. Taken together, MIR17HG displays the tumor-promotive role in the progression of OS through SP1/MIR17HG/miR-130a-3p/SP1 feedback loop. Our findings might help us to offer novel therapeutic strategies for OS.