We scored metabolic plasticity based on the metabolic enzyme expression (six metabolic protein markers) of human breast cancers with previously applied metabolic protein immunostainings (p-S6, Rictor, LDHA—lactate dehydrogenase A, GLS—glutaminase, CPT1A—carnitine palmitoyltransferase 1A, and FASN—fatty acid synthase) [38]. Here, GLS is linked to breast cancer.