Abstract
Melanocytes are specialized cells found predominantly in the skin and eyes that form the pigment melanin. Melanocytes are found also in a benign nevus, a common lesion observed in the skin which is a precursor of malignant melanoma.
Sporadic cases of melanoma predominate and can be grouped into four clinical subtypes: acral lentiginous melanoma, nodular melanoma, lentigo maligna and superficial spreading melanoma. About 60-70% of melanomas harbour mutations of the B-RAF gene, while mutations of the N-RAS are present in about 10-25% of all tumors.
Many other genes are deregulated during melanoma progression, mainly antiapoptotic genes and gene which are involved in the invasiveness, migration, and metastasis of melanoma, many of which are regulated by MITF-M (microphthalmia-associated transcription factor), a pivotal transcription factor of the melanocyte lineage.