Paclitaxel and cisplatin as intravesical agents against non-muscle-invasive bladder cancer.
OBJECTIVE
To investigate the effects of cisplatin and paclitaxel against human bladder cancer cells in vitro, and to obtain both pharmacokinetic and pharmacodynamic data after intravesical administration in mice.


METHODS
Six bladder cancer cell lines (J82, KU7, RT4, SW780, T24, UMUC3) were treated with various combined doses of both drugs and cell proliferation was evaluated 3 days later. In vivo, solutions of cisplatin and micellar paclitaxel were instilled transurethrally in female mice and pharmacokinetic data were acquired using high-performance liquid chromatography-mass spectrometry and atomic absorption methods. To obtain efficacy data, mice with orthotopic KU7-luc tumours were administered cisplatin and/or micellar paclitaxel intravesically, and the tumour burden quantified using bioluminescence imaging.


RESULTS
In vitro, both cisplatin and paclitaxel potently decreased the proliferation of all cell lines tested, and in combination had an additive but not a synergistic effect. After intravesical instillation, mouse serum concentrations of cisplatin and paclitaxel were in the low microgram/millilitre range and bladder tissue concentrations achieved were 82 and 241 microg/g, respectively. Similar drug levels were reached using combined therapy. In vivo, all chemotherapeutic agents significantly inhibited bladder tumour growth, with the best results for combined therapy and micellar paclitaxel alone. However, there was toxicity in the combined treatment arm.


CONCLUSIONS
Both cisplatin and paclitaxel were absorbed at effective amounts into bladder tissues. As intravesical agents, paclitaxel had slightly stronger anticancer potency than cisplatin. Due to increased adverse events, caution should be exercised when combining both cisplatin and paclitaxel intravesically.
Hadaschik
Boris A
BA
The Prostate Centre at Vancouver General Hospital, Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.
ter Borg
Melanie G
MG
Jackson
John
J
Sowery
Richard D
RD
So
Alan I
AI
Burt
Helen M
HM
Gleave
Martin E
ME
D000283:Administration, Intravesical; D000818:Animals; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use*; D045744:Cell Line, Tumor; D002851:Chromatography, High Pressure Liquid; D002945:Cisplatin / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use*; D005260:Female; D051379:Mice; D008819:Mice, Nude; D009361:Neoplasm Invasiveness; D017239:Paclitaxel / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use*; D001749:Urinary Bladder Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology
D017239:Paclitaxel; D002945:Cisplatin