SF188 Cells

The SF188 cell line is a human glioblastoma multiforme (GBM) model established from a pediatric patient. It is used extensively to study the mechanisms of chemotherapeutic resistance, particularly to alkylating agents such as 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). Compared to other glioma-derived cell lines such as SF126, SF188 exhibits significantly higher resistance to BCNU-induced cytotoxicity and genotoxicity. Specifically, SF188 shows approximately threefold greater resistance in survival assays and 14-fold lower susceptibility to BCNU-induced sister chromatid exchange (SCE), indicating a robust DNA damage tolerance phenotype.

The resistance in SF188 is attributed to enhanced DNA repair capacity, especially the rapid and efficient removal of O6-alkylguanine adducts. Upon exposure to methylating agents like N-methyl-N-nitrosourea, SF188 cells demonstrate marked removal of O6-methylguanine lesions, whereas more sensitive cell lines show minimal repair activity. This efficient lesion repair likely prevents the formation of interstrand crosslinks, thereby maintaining genomic integrity and increasing cell survival. Importantly, SF188 also exhibits a high chromosomal count (modal number 91) and lacks expression of glial fibrillary acidic protein (GFAP), confirming its poorly differentiated glioma origin and making it an excellent model for studying the interplay between DNA repair and chemoresistance in high-grade gliomas.