CCL2 and lung adenocarcinoma: To understand the pathophysiological relationship between miR‐210‐3p and CCL2 in the hypoxic tumor microenvironment, we established 3D spheroids of noncancerous lung epithelial cells BEAS‐2B or cancerous lung adenocarcinoma cells A549 and NCI‐H460 (Fig. 4A,B) and checked the rate of monocyte (THP‐1) infiltration in 21% oxygen (normoxic) and 1% oxygen (hypoxic) conditions at day 7.