In detail, proteasome for the regulation of protein expression, melanoma and non-small cell lung cancer for their neuroendocrine nature and phosphatidylinositol signalling system since phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) activation triggered by RET has been observed in MTC [28]. Here, AKT1 is linked to medullary thyroid gland carcinoma.