Effects of VAPs on breast carcinoma cell growth. MCF-7, HCC-1937, KPL-1 and MFM-223 breast carcinoma cells were treated with different concentrations of VAP-Qu (○), VAP-M (△), VAP-P (▽) or VAP-A (□), during 48 hours. Thereafter cell growth was determined using the MTT-colorimetric assay and the data were calculated as described under Methods. The growth of cells kept under comparable experimental conditions but in the absence of VAPs and of MLI (untreated control) was taken as 100 %. Each experiment was repeated at least twice. Data are shown as mean ± S.D.