Interstitial migration is further directed by chemotactic gradients, including CXCL8-CXCR2, CXCL2-CXCR2, and CCL21-CCR7 chemokine signalling (Lam and Huttenlocher, 2013), whereas amoeboid cancer cell chemotaxis is reliant on CXCL12-CXCR4 (Wyse et al., 2017) and CCL25-CCR9 (Zhang et al., 2011), while CCL2-CCR2 activates MEK-ROCK2-myosin II axis (Wong et al., 2020). The gene discussed is CXCL12; the disease is cancer.