Figure 4.

BCAAs metabolism in metastases. (A) In lung, although BCAAs are essential in supporting the proliferation and growth of various cancer, high level of BCAA may not promote formation of lung metastases, but on the contrary, high BCAA can inhibit lung metastasis of breast cancer by activating the tumor infiltrating-NK cells. (B) In bone, increased BCAT1 transcription can enhance BCAA catabolism to promote bone metastasis through remedy of α-KG depletion in lung cancer cells. (C) In brain, BCAAs are ingested in large quantities, and then transaminated to glutamate or oxidated for energy supply.