Table 2.

IncRNAs involved in Bone Metabolism.

LncRNA	Function	Expression	Effects
HOTAIR	Protein recruiter	Adipogenic. Upregulated in osteosarcoma	Recruits EZH2 and SUZ12 to the HoxD cluster and silences the locus. β-catenin represses HOTAIR
DANCR	miRNA sponge	Adipogenic ↓	May promote cell proliferation and differentiation toward the chondrocyte lineage
H19	miRNA sponge miRNA precursor	Osteogenic ↑ Adipogenic ↓	Functions downstream of SOX9. H19 is processed into miR-675 that subsequently upregulates COL2A1. H19 is processed into miR-675, which targets TGFβ1 for degradation. H19 acts as a ceRNA, binding to miR-141 and miR-22, blocking binding
MEG3	Protein recruiter	Osteogenic ↑ Adipogenic ↓	Upregulates BMP4 by disrupting the interaction between the SOX2 and BMP4 promoter

↑upregulation; ↓downregulation.

Abbreviations: HOTAIR, HOX Transcript Antisense RNA; DANCR, Differentiation Antagonizing Non-Protein Coding RNA; MEG3, maternally expressed 3; EZH2, Enhancer of zeste homolog 2; SUZ12, Suppressor Of Zeste 12 Protein Homolog; SOX9, sex determining region Y)-box 9; miR, microRNA; TGFβ1, tumor growth factor β-1; BMP4, bone morphogenetic protein 4.