A comparative study of the inhibiting effects of mitomycin C and polyphenolic catechins on tumor cell implantation/growth in a rat bladder tumor model.

PURPOSE

Mitomycin C (Novaplus®) is often instilled intravesically in the postoperative period to prevent tumor cell implantation/regrowth after transurethral tumor resection. In an earlier study EGCG prevented tumor cell implantation/growth in an experimental bladder tumor model simulating clinical transurethral bladder resection. We compared the efficacy of EGCG (Polyphenon E®) to that of mitomycin C to prevent tumor cell implantation/growth in this model.

MATERIALS AND METHODS

Mitomycin C and EGCG were studied for their in vitro and in vivo effects. The AY-27 rat urothelial tumor cell line was used for in vitro and in vivo studies. In vitro cell viability studies included trypan blue exclusion, MTT proliferation assay and clonal growth assay. Fischer 344 female rats were used for intravesical tumor implantation/growth assay using an electrocautery injury model. Tumor growth in vivo was assessed in controls treated with phosphate buffered saline and in bladders treated with mitomycin C or EGCG by standard histological techniques using hematoxylin and eosin 4 weeks after injury.

RESULTS

Mitomycin C and EGCG showed cytotoxicity on all in vitro assays. They were equivalent for preventing intravesical tumor growth.

CONCLUSIONS

EGCG prevents intravesical tumor growth with efficacy equivalent to that of mitomycin C in this experimental model.