Specifically, an inactivating mutation (V170fs)—in the absence of BRAF mutation—was documented in the pi3kip1 gene, whose product in humans binds to the p110 catalytic subunit of PI3K, downregulating indirectly its activity, thus underscoring the putative role of PI3K cooperation with MAPK deregulation in human melanoma [52] (Figure 3). Here, BRAF is linked to melanoma.