The overexpression of endophilin A1 in breast cancer cells is associated with its phosphorylation and translocation to mitochondria; it also enhances mitochondrial fusion and the expression of both mitochondrial fusion and biogenesis-associated proteins, such as Mitofusin 2 (MFN2) and PGC-1α. The gene discussed is SH3GL2; the disease is breast carcinoma.