SLC2A1 and breast carcinoma: Under normoxic conditions, ascorbate treatment at the individual IC50 concentrations decreased GLUT-1 expression in 30 of the 60 cell lines, with the most pronounced effects in melanoma, non-small cell lung cancer and breast cancer cell lines (Fig. 6), while in 22 of the 60 cell lines, an increased GLUT-1 expression was measured (most pronounced effect in ovarian and leukaemia cancer cell lines).