PIK3CA and osteosarcoma: Recent studies found that miR-26a (Figure 4G) and miR-29a-3p were lowly expressed in osteosarcoma and negatively correlated with IGF-1 expression, and further studies revealed that overexpression of miR-26a and miR-29a-3p could target IGF-1 to inhibit the IGF-1R/PI3K/AKT pathway to affect apoptosis and autophagy in OS cells, as evidenced by a significant attenuation of invasion (138, 210).