Abstract
Purpose: Of patients with glioblastoma who smoke tobacco, 16 to 28% will continue to smoke following diagnosis. Use of nicotine-containing products may enhance proliferation, migration and radioresistance and detrimentally affect treatment and prognosis of glioblastoma. The aim of this study is to identify effects of a period of nicotine exposure on efficacy of subsequent treatment with temozolomide and radiation therapy on 5 glioblastoma cell lines. We hypothesize that prior and continued nicotine exposure would reduce tumoricidal effects of temozolomide and radiation therapy.
Methods: After 5 glioblastoma cell cultures are exposed to nicotine prior to treatment with temozolomide and /or radiation, proliferation, migration, colony forming assays, and enzymatic expression of matrix metalloproteinases are assessed.
Results: Proliferation is not affected by exposure of physiologically relevant concentrations of nicotine prior to treatment with temozolomide or irradiation. Nicotine exposure has variable effects which include enhancement of migration rate, metalloproteinase expression, and colony formation for some glioblastoma cell lines subsequently treated with temozolomide and /or radiation therapy.
Conclusions: These findings suggest that continued smoking or use of other nicotine-containing products during treatment could result in increased aggressiveness and invasion of residual tumor cells causing a resistance to treatment in some glioblastoma.