Fig 2: Reintroduction of URGCP reverses the si-long intergenic nonprotein-coding RNA 00514 (LINC00514)-mediated inhibition of the malignant phenotype of OS cells. (A) URGCP protein expression in HOS and MG-63 cells after pc-URGCP or pcDNA3.1 transfection was detected by western blotting. (B–F) LINC00514-silenced HOS and MG-63 cells were further transfected with pc-URGCP or empty pcDNA3.1 plasmid. Cell proliferation, colony formation, and cell apoptosis and cell cycle status were assessed by Cell Counting Kit-8 assay, colony formation assay, and flow cytometry, respectively. (G, H) The migratory and invasive abilities of the aforementioned cells were assessed by transwell migration and invasion assays. *P < 0.05 and **P < 0.01.

Fig 3: URGCP promotes the malignant phenotype of OS cells in vitro. (A) Western blotting confirmed URGCP silencing in HOS and MG-63 cells after transfection with si-URGCP. (B, C) Proliferation and colony formation of URGCP-silenced HOS and MG-63 cells were determined by Cell Counting Kit-8 and colony formation assays, respectively. (D, E) Flow cytometry analysis was performed to evaluate the effect of URGCP depletion on HOS and MG-63 cell apoptosis and cell cycle distribution. (F, G) Migrated and invasive URGCP-deficient HOS and MG-63 cells were quantified using transwell migration and invasion assays. *P < 0.05 and **P < 0.01.

Fig 4: Long intergenic nonprotein-coding RNA 00514 (LINC00514) positively regulates URGCP in OS cells by sponging microRNA-708 (miR-708). (A, B) Quantitative reverse transcription polymerase chain reaction (RT-qPCR) and western blotting were conducted to measure URGCP mRNA and protein levels, respectively, in LINC00514-depleted HOS and MG-63 cells. (C) URGCP mRNA expression in the 59 pairs of OS and adjacent normal tissue samples was determined by RT-qPCR. (D) Correlation between LINC00514 and URGCP mRNA expressions in OS tissues was analyzed by Spearman’s correlation analysis (r = 0.6105, P < 0.0001). (E) Efficiency of in-miR-708 expression transfection in HOS and MG-63 cells was evaluated by RT-qPCR. (F, G) HOS and MG-63 cells were transfected with si-LINC00514 together with in-miR-708 or in-miR-NC. After transfection, the mRNA and protein levels of URGCP were determined by RT-qPCR and western blotting, respectively. *P < 0.05 and **P < 0.01.