Moreover, IL-17 recruits M2 tumour-associated macrophages (TAMs) into the microenvironment of lung tumours [51] and not only does high IL-17 expression in the microenvironment of lung tumours recruit TAMs, but it also upregulates cyclooxygenase 2 (COX2) expression in lung cancer cells. Here, PTGS2 is linked to lung carcinoma.