This implies that breast cancer DTCs colonizing the lung adapt their metabolism to utilize pyruvate to establish in the new environment by increasing the production of α-ketoglutarate through mitochondrial alanine aminotransferase 2 (ALT2) conversion, supporting collagen deposition and remodeling [111] and potentiating mTORC1 signaling [169]. This evidence concerns the gene GPT2 and breast cancer.