PHOTODYNAMIC EFFECT OF PHOTOSENSITIZERS TMPyP
AND ClAlPcS2 ON MCF7 CELL LINE IN VITRO
Pízova K.1,2, Langova K.1, Kolarova H.1
1
Department of Medical Biophysics, Faculty of Medicine and Dentistry,
Palacky University, Olomouc, Czech Republic
2
Institute of Molecular and Translational Medicine, Faculty of Medicine and
Dentistry, Palacky University, Olomouc, Czech Republic
Photodynamic therapy (PDT) is based on the tumor-selective accumulation
of photosensitizer followed by irradiation with light of appropriate
wavelength. After irradiation and in the presence of oxygen, sensitizer
induces cellular damage by generating highly reactive oxygen species
(ROS). In our in vitro study we evaluated cell viability (by standard MTT
test), amount and rate of ROS generation (by fluorescence probe CMH2DCFDA and fluorescence kinetic measurement within 10 min after
therapy) on tumour MCF7 cells after PDT with TMPyP and ClAlPcS2 in
concentrations 0, 0.5, 1, 2.5, 5 and 10 μmol/l. Samples were continuously
irradiated by light emitting diodes with excitation wavelength 414 or 660
nm at a total radiant exposure 0, 1, 5 or 10 J/cm2.
As expected, the higher photosensitizer concentration and higher total
radiant exposure led to the higher and faster ROS production and resulted
in lower cell viability. Almost all of tested therapeutic doses showed that
TMPyP induced significantly higher and faster ROS production compared
to ClAlPcS2. The highest differencies between cell viability after TMPyP
and ClAlPcS2 treatment were found in the course of intermediate
therapeutic doses (1 J/cm2 with 5 or 10 µmol/l of PS, and 5 J/cm2 with 0.5
or 1 µmol/l of PS), when TMPyP induced markedly and significantly lower
cell viability compared to ClAlPcS2. Apparently lower therapeutic doses are
not enough for tumour cell eradication in the course of both TMPyP and
ClAlPcS2. Conversely in the case of higher therapeutic doses both PSs
eradicated almost all tumour cells.
In our study we demonstrated that both tested PSs are very effective and
useful for PDT, although it turned out that TMPyP is more efficient
compared to ClAlPcS2. We believe that PDT has a great potential for
tumour treatment and is convenient to be concerned with it.
Supported by grants CZ.1.05/2.1.00/01.0030 and LF_2013_006.