On the other hand, tumor suppressor promoters are less likely to contain quadruplex-forming sequences.[14] Recent work has documented intracellular quadruplex formation [15, 16] and shown that quadruplex structures “mark” regulatory chromatin.[17] The VEGF quadruplex-forming sequence (VEGFq) is a 36bp G-C-rich region of the VEGF promoter (-85 to -50) which is essential for basal or inducible VEGF transcription. The gene discussed is VEGFA; the disease is neoplasm.