PKM and cancer: These data highlight a self-sustaining signaling loop between cancer cells and TAM that is centered on aerobic glycolysis and is involved in imparting aggressive properties to cancer cells (Figure 2) [152].Cancer cells (aerobic glycolysis) ⇒ lactate ⇒ macrophages ⇒ TAMs (secreted CCL5 ↑ and TGFβ1 ↑ ⇒ Cancer cells (CCR5 ↑, EMT ↑, HK2 ↑, PKM2 ↑, LDHA ↑) ⇒ lactate (loop)