Hence, given palbociclib’s CDK inhibitory actions and its ability to suppress signaling molecule expression and/or activation, we hypothesize that palbociclib administered at a low-cytotoxicity dose may exert anti-IgE-mediated allergy effects by down-regulating of MAPK and/or NF-κB signaling downstream of CDK6 inhibition via FcεRI, whose activation may be modulated by the Src family kinase Lyn [30]. Here, LYN is linked to Allergy.