TIMP2 and hereditary pheochromocytoma-paraganglioma: In addition, in hypoxia-injured pheochromocytoma cells, up-regulated MEG3 (maternally expressed gene 3) could recruit methylation proteins DNMT3a, DNMT3b and MBD1 to facilitate TIMP2 promoter methylation, which in turn inhibited the expression of this cell cycle arrest inducer TIMP2.