Low doses of methylnaltrexone inhibits head and neck squamous cell carcinoma growth in vitro and in vivo by acting on the mu-opioid receptor. - Gorur A; Patiño M; Shi T; Corrales G; Takahashi H; Rangel R; Gleber-Netto FO; Pickering C; Myers JN; Cata JP (Journal of cellular physiology, 2021)