In a study reported in Clinical Cancer Research, Rossmann and colleagues found that induction of oxidative stress via O3/O2 pneumoperitoneum treatment in the papillomavirus-associated rabbit auricular VX2 carcinoma model of head and neck cancer resulted in a tumoricidal immune response that could be adoptively transferred.
Auricular VX2 tumors that regressed after O3/O2 pneumoperitoneum treatment exhibited increased levels of CD3-positive tumor infiltrating lymphocytes, as well as increased expression of genes encoding receptors involved in pattern recognition, molecules required for antigen presentation and T-cell activation, and inflammatory mediators. Adoptive cell transfer of peripheral blood lymphocytes from rabbits with regressing tumors to rabbits with newly implanted VX2 tumors resulted in acquired resistance to tumor growth and produced tumor regression.
The investigators concluded: “Intraperitoneal oxidative stress effectively converts the immune response against the papillomavirus-associated rabbit VX2 carcinoma from tumor permissive to tumoricidal and leads to a sustainable, adoptively transferable oncolytic immune response.” ■
Rossmann A, et al: Clin Cancer Res 20:4289-4301, 2014.