OBJECTIVE: To present a novel treatment approach for urinary bladder cancer, protodynamic therapy, which comprises inhibition of cancer cell proliferation by intracellular acidification; cis-urocanic acid (cis-UCA) was investigated as a protodynamic drug in bladder cancer cell cultures and compared with conventional chemotherapeutic agents. MATERIALS AND METHODS: The moderately differentiated cell line 5637 and the poorly differentiated T24 cell line were exposed to cis-UCA for 0.25-2 h, and to epirubicin, doxorubicin, cisplatin and paclitaxel for 2 h, to simulate drug exposure on intravesical instillation. The combination of cis-UCA and chemotherapeutic agents was also studied. Cell viability was measured with a colorimetric assay. RESULTS: cis-UCA inhibited proliferation and suppressed the survival of cells at an extracellular pH <or= pK(a2) of 6.65 but to a lesser degree at pH > pK(a2), as suggested by the protodynamic theory. cis-UCA caused dose-dependent, irreversible termination of cell proliferation. The number of viable surviving BC cells decreased by >85% with 2%cis-UCA (P < 0.001). Viable cells disappeared completely with 4% and 6%cis-UCA after a 2-h treatment, and by 90% with 6%cis-UCA within a 15-min exposure. These effects were associated with distinct morphological changes. The other drugs tested had a clearly lower effect on cell survival. Interestingly, when combined, cis-UCA markedly enhanced the cytotoxic effect of epirubicin. CONCLUSION: cis-UCA is a potent antiproliferative agent in bladder cancer cell cultures. As our previous non-clinical studies showed that cis-UCA is locally and systemically well tolerated, protodynamic therapy with cis-UCA is a promising intravesical treatment for bladder cancer.
OBJECTIVE: To present a novel treatment approach for urinary bladder cancer, protodynamic therapy, which comprises inhibition of cancer cell proliferation by intracellular acidification; cis-urocanic acid (cis-UCA) was investigated as a protodynamic drug in bladder cancer cell cultures and compared with conventional chemotherapeutic agents. MATERIALS AND METHODS: The moderately differentiated cell line 5637 and the poorly differentiated T24 cell line were exposed to cis-UCA for 0.25-2 h, and to epirubicin, doxorubicin, cisplatin and paclitaxel for 2 h, to simulate drug exposure on intravesical instillation. The combination of cis-UCA and chemotherapeutic agents was also studied. Cell viability was measured with a colorimetric assay. RESULTS:cis-UCA inhibited proliferation and suppressed the survival of cells at an extracellular pH <or= pK(a2) of 6.65 but to a lesser degree at pH > pK(a2), as suggested by the protodynamic theory. cis-UCA caused dose-dependent, irreversible termination of cell proliferation. The number of viable surviving BC cells decreased by >85% with 2%cis-UCA (P < 0.001). Viable cells disappeared completely with 4% and 6%cis-UCA after a 2-h treatment, and by 90% with 6%cis-UCA within a 15-min exposure. These effects were associated with distinct morphological changes. The other drugs tested had a clearly lower effect on cell survival. Interestingly, when combined, cis-UCA markedly enhanced the cytotoxic effect of epirubicin. CONCLUSION:cis-UCA is a potent antiproliferative agent in bladder cancer cell cultures. As our previous non-clinical studies showed that cis-UCA is locally and systemically well tolerated, protodynamic therapy with cis-UCA is a promising intravesical treatment for bladder cancer.
Authors: J Viiri; H M Jauhonen; A Kauppinen; T Ryhänen; T Paimela; J Hyttinen; I Sorri; J K Laihia; L Leino; K Kaarniranta Journal: Mol Vis Date: 2009-09-08 Impact factor: 2.367