In a previous study focused on squamous cell carcinoma of the head and neck (SCCHN), it was observed CD56+ γδT cells, isolated from peripheral blood mononuclear cells (PBMCs) expanded under the stimulation of isopentenyl pyrophosphate (IPP) and IL-2, could effectively destroy SCCHN cell lines in a dose-dependent manner, in contrast to CD56- γδT cells (64). This evidence concerns the gene IL2 and head and neck squamous cell carcinoma.