Photodynamic effects in vitro in fresh gynecologic tumors analyzed with a bioluminescence method.
Photodynamic therapy (PDT) is a promising alternative method for clinical cancer treatment. In the present study, cells from four breast carcinomas, seven ovarian carcinomas of various stages of differentiation, and ascites from a diffuse metastatic tumor were treated by PDT in vitro. Tetra(m-hydroxyphenyl)-chlorin (m-THPC) was used as the photosensitizer. Surviving cell rate was evaluated by the ATP-Cell-Viability-Assay (ATP-CVA), which measures light production as an interaction of intracellular ATP with the luciferin-luciferase complex. The most effective PDT of the tumor cells was achieved at an m-THPC concentration of 0.2 microgram/ml following incubation of the cells with photosensitizer for 24 hours. PDT toxicity resulted in a cell survival rate of 1% to 42% compared to untreated control cells (survival rate of control = 100%). The inhibitor concentration IC50 of m-THPC was determined both in the dark (dark toxicity) and in combination with laser irradiation. IC50 was defined as the concentration of photosensitizer which caused 50% of cell death. The IC50 values were heterogeneous in all tumor specimens examined. IC50 values for dark toxicity were on average 0.14 microgram m-THPC/ml for primary ovarian carcinoma, 2.16 micrograms m-THPC ml for refractory ovarian carcinoma and 0.3 microgram m-THPC/ml for breast carcinoma. After PDT, average IC50 value for refractory ovarian carcinoma was 0.04 microgram m-THPC/ml, for primary ovarian carcinoma 0.05 microgram m-THPC/ml and for breast carcinoma 0.03 microgram m-THPC/ml. These data might indicate that clinical PDT of gynecological carcinoma requires individual treatment conditions to achieve optimal results.
Schlosser
V
V
Department of Obstetrics and Gynecology, University of Basel, Switzerland.
Koechli
O R
OR
Cattaneo
R
R
Jentsch
B
B
Haller
U
U
Walt
H
H
D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D002470:Cell Survival; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008163:Luminescent Measurements; D008652:Mesoporphyrins / Q000627:therapeutic use*; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000473:pathology; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use*
D008652:Mesoporphyrins; D017319:Photosensitizing Agents; C072269:temoporfin