Chemoprevention with green propolis green propolis extracted in L-lysine versus carcinogenesis promotion with L-lysine in N-Butyl-N-[4-hydroxybutyl] nitrosamine (BBN) induced rat bladder cancer

purpose: to determine the effects of green propolis extracted in l-lysine (wsdp) and of l- lysine for 40 weeks on induced rat bladder carcinogenesis. methods: the animals (groups i, ii, iii, iv, v and vi) received bbn during 14 weeks. group i was treated with propolis 30 days prior received bbn, and then these animals were treated daily with propolis; groups ii and iii was treated with subcutaneous and oral propolis (respectively) concurrently with bbn. the animals of group iv were treated l-lysine; group v received water subcutaneous; and group vi received only to bbn. among the animals not submitted to carcinogenesis induction, group vii received propolis, group viii received l-lysine and group ix received water. results: the carcinoma incidence in group i was lower than that of control (group vi). the carcinoma multiplicity in group iv was greater than in group vi. all animals treated with l-lysine developed carcinomas, and they were also more invasive in group iv than in controls. on the other hand, group viii showed no bladder lesions. conclusion: the wsdp is chemopreventive against rat bladder carcinogenesis, if administered 30 days prior to bbn , and that l-lysine causes promotion of bladder carcinogenesis.