Femtosecond laser induced photodynamic therapy on 5-ALA treated SKMEL-30 cells: an efficient theranostic strategy to combat melanoma.
OBJECTIVE
Photodynamic therapy (PDT) is a type of photo-chemotherapy that is based on the application of photosensitizer and irradiation of the region by laser sources. Photosensitizer and light interaction will develop reactive oxygen radicals ((1)O2) in the cells and elimination of cells by apoptosis or necrosis.


METHODS
Metastatic skin cancer cells SKMEL-30 were treated by 5-ALA in dark and then they were irradiated by 90-femtosecond (fs) laser with different pulse powers for different durations. The effects of 5-ALA mediated photodynamic therapy on the cells were determined by XTT proliferation kit and by flow cytometry measurements of Annexin V, 7-AAD and mitochondrial membrane potential alterations. Fluorescent accumulation of protoporphyrin IX was investigated by fluorometry and confocal laser microscope.


RESULTS
The viability tests for SKMEL-30 cells treated with different 5-ALA doses and femtosecond laser power and durations demonstrated that 635 nm, 45 mW pulse energy at 90 fs laser pulse applications for 60 sec to 1mM 5-ALA exposed cells decreased the cell proliferation by 30%. Flow cytometric measurements exhibit that PDT caused 63% of mitochondria membrane potential alteration, 30% of cell death in the population by apoptosis and 39% of cells by necrosis. There was 1mM 5-ALA exposure that also exhibited about 32% accumulation of fluorescence in the cells.


CONCLUSIONS
The pretreatment of the cells with the precursor 5-ALA lets the imaging due to increased protoporphyrin IX fluorescence. This treatment method may be proposed as an effective theranostic strategy for melanoma because of its rapid and effective anticancer consequences.
Sarayönü Vocational High School, Selçuk University, 42430 Konya, Turkey; Advanced Technology Research and Application Center, Selçuk University, 42075 Konya, Turkey. Electronic address: dmeltem@yahoo.com.
Meltem Demirel
MD
Kars
Advanced Technology Research and Application Center, Selçuk University, 42075 Konya, Turkey.
Reyhan
R
Kara
Department of Physics, Faculty of Science, Selçuk University, 42075 Konya, Turkey.
Yasemin
Y
Gündoğdu
Department of Physics, Faculty of Science, Selçuk University, 42075 Konya, Turkey.
Abdullah
A
Kepceoğlu
Advanced Technology Research and Application Center, Selçuk University, 42075 Konya, Turkey; Department of Physics, Faculty of Science, Selçuk University, 42075 Konya, Turkey.
Hamdi Şükür
HŞ
Kılıç
D000368:Aged; D000622:Aminolevulinic Acid / Q000494:pharmacology / Q000627:therapeutic use*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D005434:Flow Cytometry; D005453:Fluorescence; D006801:Humans; D007834:Lasers; D008297:Male; D008545:Melanoma / Q000188:drug therapy* / Q000473:pathology; D010778:Photochemotherapy; D011524:Protoporphyrins / Q000378:metabolism; D012878:Skin Neoplasms / Q000188:drug therapy* / Q000473:pathology; D013997:Time Factors
D011524:Protoporphyrins; D000622:Aminolevulinic Acid; C028025:protoporphyrin IX
Apoptosis; Femtosecond laser; Melanoma; Mitochondria membrane potential; Photodynamic therapy