TY - JOUR
T1 - Effects of photodynamic therapy on glioma spheroids
AU - Terzis, A. J.A.
AU - Dietze, A.
AU - Bjerkvig, R.
AU - Arnold, H.
N1 - Funding Information:
This work was supported by grants from the Depart-mentofNeurosurgery,LuÈ beck,theNorwegianCan-cer Society, and the Norwegian Research Coun- cil. Technical assistance from Ms E. Pawlak is greatly appreciated.
PY - 1997
Y1 - 1997
N2 - The present study describes the sensitivity of glioma cells to a haematoporphyrin derivative (Photosan-3® under laser activation (argon-pumped dye laser). The effects of photodynamic therapy (PDT) on cell growth, directional migration and cell invasion were investigated on two human glioma cell lines (GaMg and U-251Mg). The directional cell migration and spheroid growth was determined for both cell lines exposed to increasing laser energy output (15-35J/cm2) with concentrations of 5 and 7 μg/ml of Photosan-3®. Both cell lines showed a dose-dependent migratory response to increasing laser irradiation, that was more prominent in the 7 μg/ml treatment group. This effect occurred during the first 4 days after drug exposure. Also, spheroids from both cell lines showed a drug and laser output energy dose-dependent inhibition of growth which became apparent after a lag period of 6 days. The lag period was characterized by a decreased growth rate as compared with the control group. During this period the outer cell layers of the spheroids fell apart. The remaining spheroid tissue was not able to migrate and to regrow when exposed to the highest laser energy outputs (30-35J/cm2, 5 and 7 μg/ml Photosan-3®). These spheroids showed, however, the ability for invasion when confronted with normal brain cell aggregated in vitro. Light microscopic observations of co-cultures between tumour tissue and brain cell aggregates revealed a normal tumour morphology. This indicates that the remaining tumour cells were not dead and could be stimulated to invade the normal tissue when exposed to a normal brain microenvironment.
AB - The present study describes the sensitivity of glioma cells to a haematoporphyrin derivative (Photosan-3® under laser activation (argon-pumped dye laser). The effects of photodynamic therapy (PDT) on cell growth, directional migration and cell invasion were investigated on two human glioma cell lines (GaMg and U-251Mg). The directional cell migration and spheroid growth was determined for both cell lines exposed to increasing laser energy output (15-35J/cm2) with concentrations of 5 and 7 μg/ml of Photosan-3®. Both cell lines showed a dose-dependent migratory response to increasing laser irradiation, that was more prominent in the 7 μg/ml treatment group. This effect occurred during the first 4 days after drug exposure. Also, spheroids from both cell lines showed a drug and laser output energy dose-dependent inhibition of growth which became apparent after a lag period of 6 days. The lag period was characterized by a decreased growth rate as compared with the control group. During this period the outer cell layers of the spheroids fell apart. The remaining spheroid tissue was not able to migrate and to regrow when exposed to the highest laser energy outputs (30-35J/cm2, 5 and 7 μg/ml Photosan-3®). These spheroids showed, however, the ability for invasion when confronted with normal brain cell aggregated in vitro. Light microscopic observations of co-cultures between tumour tissue and brain cell aggregates revealed a normal tumour morphology. This indicates that the remaining tumour cells were not dead and could be stimulated to invade the normal tissue when exposed to a normal brain microenvironment.
KW - Glioma
KW - Haematoporphyrin derivative
KW - Invasiveness
KW - Photodynamic therapy
KW - Three-dimensional culture
UR - http://www.scopus.com/inward/record.url?scp=0030989846&partnerID=8YFLogxK
U2 - 10.1080/02688699746249
DO - 10.1080/02688699746249
M3 - Article
C2 - 9231006
AN - SCOPUS:0030989846
SN - 0268-8697
VL - 11
SP - 196
EP - 205
JO - British Journal of Neurosurgery
JF - British Journal of Neurosurgery
IS - 3
ER -