MAP2K7 and melanoma: Furthermore, excessive levels of ROS, such as those caused by the administration of chemotherapeutic agents, induce the development of resistance mechanisms to the oxidative environment; such resistance has been studied in the human melanoma cell line A375, in which the activation of the mitogen-activated protein kinase (MAPK) pathway (RAS/MEK/ERK) and the transcription factors hypoxia-inducible factor 1 (HIF-1α) and the master regulator of melanocyte differentiation, microphthalmia-associated transcription factor (MITF), were observed.