On the opposite, p-MEK levels remained low during the kinetic in RET/PTC3 cells reflecting multiple negative feedback mechanisms upstream of MEK and accordingly, p-MEK levels were further induced after treatment with the MEK kinase inhibitor as well as in BRAF wild-type human thyroid cancer cells (release of negative feedback loop from ERK). The gene discussed is NCOA4; the disease is thyroid gland carcinoma.