RUNX2 and breast cancer: Huang et al. (2018) identified circ-0000144 as a novel oncogene in BC, because its expression is significantly upregulated in BC, compared with adjacent non-tumor tissues, and high levels of circ-0000144 expression are associated with a poor prognosis. Functionally, circ-0000144 knockdown attenuates BC cell proliferation and invasion in vitro, and reduces tumor volumes in vivo. Mechanistically, circ-0000144 is a sponge for miR-217, and RUNX2 is a target of miR-217. circ-0000144 enhances RUNX2 expression by repressing miR-217 and thus exerts oncogenic activities in BC.