The antitumor activity of [bpyH][VO(nta)(H<sub>2</sub>O)]H<sub>2</sub>O and its phenanthroline analogue, [phenH][VO(nta)(H<sub>2</sub>O)](H<sub>2</sub>O)<sub>0.5</sub>, towards human osteosarcoma cell lines (MG-63 and HOS) has been assessed (the LDH and BrdU tests) and referred to cis-Pt(NH<sub>3</sub>)<sub>2</sub>Cl<sub>2</sub> (used as a positive control).
Although the human osteosarcoma cell lines HOS and MG63 have a wild-type RB gene, SaOS-2 and OSrb (established from retinoblastoma patient) have no active RB gene.
The mRNA and protein levels of ANXA3 in the osteosarcoma cell lines HOS and U2OS were significantly increased compared with osteoblasts, particularly in HOS cells.
We found that Oridonin at sub-toxic concentrations synergistically enhanced Nutlin-3-mediated cell viability inhibition in wild-type p53 U2OS and SJSA-1, but not in p53-mutant MNNG/HOS and in null-p53 Saos-2 osteosarcoma cell lines.
Western analysis suggested that saurolactam treatment resulted in a reduction of Akt/PKB, phospho-Ser473-Akt, c-Myc, and S-phase kinase-associated protein 2 (Skp2) in MG-63 and HOSosteosarcoma cells.
The roles of miR-142-3p in osteosarcoma development were studied using cultured HOS, MG63 and Saos-2 cells and tumor xenograft analyses in nude mice; their target genes were also investigated.
Results showed that KLF6 displayed a significant downregulation in osteosarcoma cell lines (MG63, SaOS-2, U2OS, and HOS) compared with human osteoblastic cell line (hFOB1.19).
Adenoviral mediated overexpression and knockdown of IGFBP5 in the MG63 and MG63.2 cell lines, as well as other OS lines (143B and MNNG/HOS) that are independent of our MG63 lines, were employed to examine the role of IGFBP5.
The 143B-GFP cell line with high metastatic potential and the MNNG/HOS-RFP cell line with low metastatic potential, both derived from the TE85 human osteosarcoma cell line, were either co-transplanted or transplanted alone in the tibia in nude mice.
To confirm the influence of per2 gene on MNNG/HOS human osteosarcoma cells, small interfering (si)RNA against per2 or plasmids containing per2 were transfected into MNNG/HOS cells, and the proliferation, apoptosis and migration were observed.
This peptide specifically was found to bind to the CD105‑positive osteosarcoma MNNG/HOS cell line and the osteosarcoma cells in the histological sections derived from an MNNG/HOS xenograft model and osteosarcoma patients in vitro.
Interestingly, MTT assays in MG-63 and MNNG/HOSosteosarcoma cells exhibited that half-maximal inhibitory concentration (IC<sub>50</sub>) value of RGD-DOX-PM was much lower than its non-targeted counterpart (DOX-PM), implying RGD decorated nanoparticles had enhanced cell targeting ability and led to more effective anti-tumor effect.
We then utilized the CRISPR-Cas9 system to specifically silence CD44 in highly metastatic human osteosarcoma cells (MNNG/HOS and 143B) and further determined the functional effects of CD44 knockout in these cells.
The elevated level of NEAT1 was confirmed in OS cell lines including MG63 and HOS <i>in vitro</i> Knockdown of NEAT1 by two siRNAs induced impaired cell vitalities, promoted the apoptosis, and G<sub>0</sub>/G<sub>1</sub> arrest in two cell lines, which was associated with inhibited anti-apoptosis signals BCL-2 pathway and cell cycle-related cyclin D1 (CCND1) signals.
To examine the antitumor effects of gallic acid (GA) on osteosarcoma, two human osteosarcoma cell lines U-2OS and MNNG/HOS were treated by GA and subjected to cell proliferation and apoptosis assays.
In conclusion, the HOS 58 osteosarcoma cell line represents a differentiated cell line with highly expressed and physiologically regulated AP expression during further differentiation in culture.