Photodynamic therapy sensitizes bladder cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) mediated apoptosis
Article published in Urologia Polska 2008/61/Supl. 1.

authors

Ewelina Szliszka, Zenon Czuba, Aleksandra Kawczyk, Aleksander Sieroń, Wojciech Król

Katedra i Zakład Mikrobiologii i Immunologii w Zabrzu, Śląski Uniwersytet Medyczny w Katowicach

summary

Introduction.

Photodynamic therapy (PDT) is currently being used as an alternative treatment modality for superficial bladder tumors. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor super family capable of inducing apoptosis preferentially in cancer cells. However, not all cancer cells are susceptible to TRAIL. TRAIL-resistant cancer cells can be sensitized to TRAIL induced apoptosis by anticancer agents, for example PDT.

Objectives.

We investigated the combined cytotoxic effect of TRAIL and PDT with photofrin on bladder cancer cells.

Materials and methods.

Three human transitional bladder cancer cell (TCC) lines: SW780, 647V, T24 were initially tested for TRAIL sensitivity. Our results revealed that SW780 cells were relatively sensitive, 647V and T24 were resistant to TRAIL. We therefore examined the cytotoxic and apoptotic effect of low dose PDT with photofrin in

combination with TRAIL on TCC cell lines. Cytotoxicity was determined by microculture tetrazolium (MTT) assay. Apoptosis was quantificated by microscopic fluorescence method using Apoptotic Cells Quantification Kit.

Results.

Treatment of bladder cancer cells with photofrin-PDT significantly augmented TRAIL induced cytotoxicity in bladder cancer cells. We reported that photodynamic therapy overcomes TRAIL-resistance in TCC cell line. PDT sensitizes bladder cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) mediated apoptosis.

Conclusions.

The obtained results indicate that combined effect of TRAIL and photofrin-PDT may provide the basis for a new therapeutic approach to induce cancer killing in superficial bladder tumor.