Apoptosis in glioma cells treated with PDT.
BACKGROUND
Despite significant advances in neurosurgical techniques, the median survival time of patients with glioblastoma has improved little over the past 50 years and remains less than one year. Photodynamic therapy (PDT) is presently established as a widely accepted modality for the treatment of a variety of solid tumors.


OBJECTIVE
This study evaluated the effect of PDT-Photogem(®) on five glioma cell lines (U87, U138, U251, U343, and T98G).


METHODS
The experiments were carried out in 25-cm(3) flasks with different groups of cells seeded at a density of 1 × 10(5) cells per flask. After 3 h, the medium was removed, and the cells were incubated for 4 h with Photogem (5 μg/mL). After the incubation time, the photosensitizer-containing medium was removed and the cells were irradiated with LED (630 nm, 25 mW/cm(2), 25 J/cm(2)) devices for 17 min. For the final steps of the PDT, the cells were returned to the incubator and kept at 37°C with 5% CO(2) for 24 h, the cell viability assay was assessed using the trypan blue method, and the expression of Caspase 3 mRNA levels was assessed by real-time quantitative PCR.


RESULTS
Upon PDT-Photogem(®) treatment, viable cells, as evaluated by the trypan blue dye-exclusion method, decreased in two cell lines (U87 and U138) but not in the other three. Apoptosis, as assessed by the expression of caspase-3 mRNA levels, was at least partly involved in the death mechanism of the cell lines.


CONCLUSIONS
Collectively, our results indicated that PDT-Photogem(®) can act in glioma cells, thus encouraging new experiments in this field.
Department of Surgery and Anatomy, University of São Paulo (USP), Brazil.
Luis Fernando
LF
Tirapelli
Marcelo
M
Morgueti
Daniela Pretti
DP
da Cunha Tirapelli
Vanderlei Salvador
VS
Bagnato
Juliana
J
Ferreira
Fermino Sanches Lizarte
FS
Neto
Fernanda Maris
FM
Peria
Harley Francisco
HF
Oliveira
Carlos Gilberto Carlotti
CG
Junior
D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D018929:Cell Culture Techniques; D045744:Cell Line, Tumor / Q000187:drug effects / Q000528:radiation effects; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D005910:Glioma / Q000188:drug therapy / Q000473:pathology* / Q000532:radiotherapy; D006801:Humans; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000494:pharmacology* / Q000627:therapeutic use
D017319:Photosensitizing Agents