A report showed that under hypoxic conditions, renal cell carcinoma cell lines induced the TNF-α signalling pathway via GM-CSF, CXCL2, CXCL3 and PTGS2.34 Interestingly, these signalling factors were also observed to be upregulated in the cytokine array after anti-VEGF treatment in this study. The gene discussed is PTGS2; the disease is hereditary clear cell renal cell carcinoma.