FASLG and lip and oral cavity carcinoma: Therefore, to confirm the role of ERK and p38 inhibition in Lico-A-induced FasL expression, KB oral cancer cells were pre-stimulated with pharmacological inhibitors (PD98059 for ERK and SB203580 for p38) for 2 h to turn off each MAPK signaling and then Lico-A was administered for 24 h.