Studies in B16F10 mouse melanoma cells have provided evidence to suggest that LTA isolated from Lactobacillus plantarum can prevent melanogenesis by inhibiting the expression of melanogenic enzymes and cellular activity of tyrosinase, while activating the PI3K/Akt pathway and ERK.32 A very recent study has demonstrated that exposure of a cell-free extract of Enterococcus faecium L-15 to mouse skin-derived precursor cells (SKPs) could result in improvement of self-renewal and proliferation of SKPs by activation of the PI3K/Akt signaling pathway. The gene discussed is AKT1; the disease is melanoma.