LECTIN-INDUCED ALTERATIONS ON THE PROLIFERATION OF 3 HUMAN PROSTATIC-CANCER CELL-LINES

While lectins are known to influence the cell growth of several types of normal and neoplastic tissues, their roles in the case of prostatic cancer cells remain relatively unexplored. In the present work, we re port the in vitro influence of five lectins, namely peanut (PNA), whea t germ (WGA), Concanavalin A (Con A), Griffonia simplicifolia (GSA-IA( 4)), and Phaseolus vulgaris (PHA-L) agglutinins, on the cell prolifera tion of one androgen-sensitive (LNCaP) and two androgen-insensitive (P C-3 and DU 145) human prostatic cancer cell lines cultured in either 1 0% or 1% fetal bovine serum (FBS)-supplemented media. The cell prolife ration was assessed by means of the colorimetric -(4,5-dimethythiazol- 2-yle)2,5-diphenyltetrazolium bromide. (MTT) assay. Four lectin concen trations were tested (i.e., 0.1, 1, 10, and 100 mu g/ml) at five exper imental states (i.e., 2, 3, 5, 7, and 9 d following the addition of ea ch lectin to the culture media). Our results demonstrated that the fiv e lectins under study had a globally significant dose-dependent toxic effect on prostatic cancer cell proliferation. Nevertheless, low doses of GSA-IA, and PHA-L significantly (P < 0.05 to P < 0.001) increased the cell proliferation of confluent PC-3 cells. Increasing the FBS fro m 1% to 10% in the culture media significantly antagonized lectin-indu ced toxicity in the three prostatic cell lines. In conclusion, the pre sent data strongly suggest that some lectins might influence the proli feration of prostatic carcinoma cells. In addition, because lectins ar e present in our diet, and are able to pass into the systemic circulat ion and thus reach the prostate, the present results suggest that some lectins might exert an influence on prostate cancer growth under clin ical conditions.