IN-VITRO INFLUENCE OF PHASEOLUS-VULGARIS, GRIFFONIA-SIMPLICIFOLIA, CONCANAVALIN-A, WHEAT-GERM, AND PEANUT AGGLUTININS ON HCT-15, LOVO, AND SW837 HUMAN COLORECTAL-CANCER CELL-GROWTH

Background/Aims-Compared with normal colonic mucosa, lectin receptor e xpression is increased in hyperplastic and neoplastic tissues; some le ctins have been shown to influence human colonic epithelial cell proli feration. The aim was to assess further the influence lectins (Phaseol us vulgaris Griffonia simplicifolia (GSA), concanavalin A (Con A), whe at germ (WGA), and peanut (PHA-L) agglutinins) on cellular growth in t hree human colorectal cancer cell lines (LoVo, HCT-15 and SW837). Meth ods-Cells were cultured in four lectin concenrations (0.1, 1.0, 10, an d 100 mu g/ml) and growth assessed at days 2, 3, 5, and 7. The experim ents were performed in media supplemented with either 1% or 10% fetal calf serum (FCS). Growth was assessed using the MTT (3-(4,5)-dimethylt hiazol-2-yl)-2,5-diphenyl tetrazolium bromide) colorimetric assay. Res ults-Growth in each cell line was greatly affected by at least two of the lectins tested. There was some variation in the effect of a given lectin on different cell lines. Lectin effects showed a dose-response and the greatest effects generally resulted from the highest concenrat ions at the longest culture time. WGA and Con A induced large effects in all cell lines; the effects of Con A were partly blocked by the hig her concentration of FCS. PNA had modest and uniform stimulatory effec ts overall. The effects of GSA and PHA-L varied between cell lines. Co nclusions-The lectins studied all have the potential to affect colonic cancer growth in vitro. Many dietary lectins are resistant to digesti on and may have important effects in vitro but the definition of their role in human colonic cancer biology must take into account the varia bility in lectin response.