Deleterious effects on MDAMB-231 breast adenocarcinoma cell lineage submitted to Ho-166 radioactive seeds at very low activity

Herein, the deleterious effect of ionizing radiation provided by Ho-166 radioactive seeds at low activity were addressed, based on experimental in vitro assays at the MDA MB231 cell lineage, a breast adenocarcinoma, compared to PBMC - peripheral blood cells. The methodology involves of the MDBMB-231 and PBMC expansion in culture in suitable environment in 30mm well plates and T-25 flasks. Seeds were synthesized with Ho-165 incorporated and characterized previously. Activation was processed at IPR1 reactor at the peripheral table, at 8h exposition. Three groups of seeds were tested: 0,34 mCi, 0,12 mCi activity, and control group. Such seeds were placed on culture and held to a period of 05 half-lives of the radionuclide. The biological responses at these exposure were documented by inverse microscopic photographic in time. Also, MTT essay were performed. A fast response in producing deleterious effects at cancer cell was observed even if for the low activity seeds. Also, a biological response dependent to a radial distance of the seed was observed. At conclusion, viability clonogenic control of MDAMB231 is identified at the exposition to Ho-166 ceramic seeds, even if at low activity of 0,1 to 0,3mCi. (author)