MTOR and melanoma: Melanocytic nevi, a benign proliferation of melanocytes, which can give birth to malignant melanoma, show in many cases elevated PLD2 expression as well as activation of Akt, whereas LKB1 expression is still high in most cases, suppressing aberrant mTOR activation, which occurred only in 25% of the analysed specimen (Fig. 6a’–d’).