Table 2. The miRNA involvement in bone metastasis and osteosarcoma.
| Tumor seeding | Activity | Validated targets | Model | Reference |
|---|---|---|---|---|
| Let-7g | Inhibits migration, bone metastasis | HMGA2 | Human breast cancer cell lines, intracardiac injected bone metastasis in mice | 58 |
| miR-17 | Enhances migration and metastasis | Human breast cancer cell lines, spontaneous bone metastasis in mice | 59 | |
| miR-335 | Inhibits invasion, bone metastasis | Sox4, Tenascin C | Human breast cancer cell lines, intracardiac injected bone metastasis in mice | 60,61 |
| miR-206 | Inhibits invasion, dissemination | Human breast cancer cell lines, intracardiac injected bone metastasis in mice | 60 | |
| miR-203 | Inhibits bone metastasis | Zeb2, Bmi, Survivn, Runx2 | Human prostate cancer cell lines, intracardiac injected bone metastasis in mice | 67 |
| miR-16 | Inhibits bone metastasis | Human prostate cancer cell lines, systemic miR-16 inhibits bone metastasis | 68 | |
| miR-146a | Inhibits proliferation and adhesion to endothelial cells, | ROCK | Human prostate cancer PC3 cells in vitro | 69 |
| miR-145 | Inhibits migration, seeding | HEF1 | Human prostate cancer PC3 cells in vitro | 70,71 |
| Bone marrow microenvironment | ||||
| miR-218 | Osteomimicry in breast cancer cells | SOST, DKK2, SFRP2 | Human breast cancer cells in vitro | 62 |
| miR-126 | Knockdown enhances bone metastasis, inhibits endothelial cell recruitment in lung | IGFBP2, PITPNC1, MERTK | Human breast cancer cell lines, intracardiac injected bone metastasis in mice | 65 |
| miR-31 | Regression of established metastasis | ITGA5, RDX, RhoA | Human breast cancer cell lines, intracardiac injected bone metastasis in mice | 66 |
| miR-33a, miR-133a, miR-141, miR-190, miR-219 | Inhibits osteoclast differentiation in vitro and in vivo | Mmp14, Mitf, Calcr, Traf6 | Human breast cancer cell lines, intracardiac injected bone metastasis in mice | 72 |
| miR-33a | Inhibits lung cancer induced osteoclastogenesis | PTHrP | Human lung cancer cell lines in vitro | 73 |
| Let-7 | Inhibits IL-6 in tumor-associated MSCs | IL-6 | Human prostate cancer PC3 cells in vitro | 74 |
| Osteosarcoma | ||||
| miR-16 | Tumor suppressor | Human osteosarcoma cells in vivo injected in mice | 40 | |
| miR-126 | Inhibits invasion, induces apoptosis | Sox2 | Human osteosarcoma cells in vitro | 41 |
| miR-183 | Inhibits migration/invasion, | Ezrin | Human osteosarcoma cells in vitro | 42 |
| miR-143 | Inhibits migration/invasion, suppresses lung metastasis | MMP13 | Human osteosarcoma cells inoculated in knee, intravenous injection of miR-143 | 43 |
| miR-27a | Enhances migration, bone metastasis | Human osteosarcoma cells in vivo injected in mice | 40 | |
| miR-21 | Enhances migration/invasion | RECK | Human osteosarcoma cells in vitro | 44 |
| miR-140 | Chemoresistance to methotrexate and 5-fluorouracil | HDAC4 | Human osteosarcoma cells in vitro | 46 |
| miR-215 | Chemoresistance to methotrexate and Tomudex | DHFR, TS | Human osteosarcoma cells in vitro | 45 |
Abbreviations: IL-6, interleukin-6; MSC, mesenchymal stem cell.