MORPHOLOGICAL TRANSFORMATION-INDUCED BY GLASS-FIBERS IN BALB C-3T3 CELLS/

Studies were conducted to determine whether 1) glass fibers can induce morphological transformation in BALB/c-3T3 cells, 2) the transforming activity of glass fibers is related to fiber size, and 3) transformed cells induced by glass fibers pos sess neoplastic properties. In the transformation assay, BALB/c-3T3 cells were treated with three differe nt types of glass fibers: Manville code 100 (JM-100, Manville Corp., D enver, CO), Owens-Coming AAA-10 (AAA-10, Owens-Coming Corp., Toledo, O H), and Owens-Coming general building insulation (ISL, Owens-Coming Co rp.) fibers. The neoplastic properties were investigated using the sof t agar cloning and gene transfection methods. All three different glas s fibers were cytotoxic at high concentrations and induced dose-relate d increases in morphological transformation. The transforming activity was inversely related to fiber size, with AAA-10 showing higher activ ity than JM-100 and JM-100 showing higher activity than ISL fiber. Tra nsformed cells induced by glass fibers exerted anchorage-independent g rowth (90%) and DNA transfection-mediated transformation (100%). These results indicate that glass fibers are capable of transforming mammal ian (BALB/c-3T3) cells in vitro as a function of their physical proper ties and that glass fiber-induced transformed cells possess preneoplas tic characteristics. (C) 1995 Wiley-Liss, Inc.