PIK3CA and medulloblastoma: We also investigated whether the specific inhibition of p110α was able to resensitize chemoresistant ovarian cancer cells to PTX, because p110α is a major isoform for the signaling and growth of tumors driven by oncogenic RTKs/RAS [28], and targeting PI3K p110α was reported to inhibit tumor cell proliferation, chemoresistance, and migration in medulloblastoma cells [29].