lncRNA JPX modulates malignant progress of osteosarcoma through targeting miR-33a-5p and PNMA1 regulatory loop.

Osteosarcoma (OS) is a common type of bone tumor, present worldwide, that has distal metastasis ability. Although continuous development in cancer therapy has taken place, there are still no effective metastasis-curbing strategies for OS available. Hence, a better understanding of the biological characteristics and molecular mechanisms of OS carcinogenesis is urgently needed. Long noncoding RNAs (lncRNAs) have captured great interest among cancer scientists with considerable potential implications for cancer treatment. In this study, we found that lncRNA JPX was up-regulated in OS tissues and cells. We subsequently examined the functional role of JPX in OS cells through knocked-down JPX by using siRNA. JPX down-regulation was observed to suppress OS cell proliferation, migration and invasion. Furthermore, it was verified that JPX acts as a sponge for miR-33a-5p, and that JPX regulated OS cell proliferation, migration and invasion through miR-33a-5p. Moreover, down-regulation of miR-33a-5p in OS contributed to PNMA1 upregulation, and PNMA1 depletion inhibited OS cell proliferation, migration and invasion in vitro. Taken together, our data support an important role of JPX in regulating OS cell proliferation, invasion and migration that highlights JPX may be a potential therapeutic target for OS.