ABSTRACTS – ORAL PRESENTATIONS - AMCA, spol. s r.o.

was harmful neither alone nor in combination to normal cells, which can be a possible
rationale for future clinical trials.
Acknowledgements
This work was supported by MŠMT grant CZ.1.07/2.3.00/30.0030, by MZD grant
NT13573-4/2012; by the AVCR grant AV0Z50040702, and by the project FNUSA-ICRC
CZ.1.05/1.1.00/02.0123 from the European Regional Development Fund.
References
Guzi, T.J., et al.: Targeting the replication checkpoint using SCH 900776, a potent and
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P33. THE EFFECTS TO MOLECULAR BIOMEMBRANE TRANSPORT HYPERFORIN OR
ARISTOFORIN IN COLON ADENOCARCINOMA CELLS
Martina Šemeláková, Rastislav Jendželovský, Jaromír Mikeš, Peter Fedoročko
Institute of Biology and Ecology, Faculty of Sciences, P.J. Šafárik University in Košice,
Slovak Republic; martina.semelakova@upjs.sk
Photodynamic therapy is an anti-cancer approach for the treatment of various types
of non-malignant as well as malignant diseases. Hypericin (HY), a naturally-occuring
photosenzitive compound synthesized by Hypericum sp. (St. John’s wort), posses
properties suitable for PDT and demonstrates photocytotoxic activity both in vitro and
in vivo (Agostinis et al., 2000). Hyperforin is a phloroglucin-derivative that has emerged
as a key player not only in the antidepressant activity of the plant’s extract but also as
a suppressor of bacteria, lymphocyte and tumor cell proliferation (Erdelmeier, 1998),
and as an inhibitor of matrix proteinases. Aristoforin, however, one of hyperforin’s
synthetically prepared derivatives, has proved to be more soluble and even stable in
aqueous solution. Importantly, it retains the antitumor properties of the parental
compound without inducing toxicity in experimental animals. These data strongly
suggest that AR has even greater potential as an anticancer drug (Gartner et al., 2005).
Our previous results (Semelakova et al., 2012) showed that hypericin (HY)-mediated
photodynamic therapy (HY-PDT) in sub-optimal dose with hyperforin (HP) (both bioactive
compounds naturally occuring in plants of Hypericum sp.), or its stable derivative
aristoforin (AR) were able to stimulate mechanisms leading to significant antitumor
activity. Both, HP or AR were used at relatively low concentrations up to 5 μM. Significant
accumulation of HY in cells after 16 h of incubation with drugs was described.
Generally, the therapeutic efficacy of various chemotherapeutics is severely limited by
drug resistance that is related to overexpression of drug efflux transporters in tumour
cells. Therefore the impact of HY, HP or AR on cell’s ATP-binding cassette membrane
transporter system, namely multidrug resistance-associated protein 1 (MRP1/ABCC1)
and 2 (MRP2/ABCC2), breast cancer resistance protein (BCRP), P-glycoprotein (P-gp/
MDR1) and cytochrome P450 monooxygenase, was subsequently evaluated by Western
blot analysis of proteins, mRNA expression by qRT-PCR and flowcytometric analysis of
126 Analytical Cytometry VII