NDUFS6 and breast neoplasm: Therefore, we analysed the expression of 6 genes from the OXPHOS signature (AIFM1, NDUFV1, NDUFAB1, NDUFA7, NDUFS6 and MRPS12) among the most enriched in metastatic samples, by RT-PCR in specimens of 503 breast tumours patients with a follow-up of 20 years.