In vitro photodynamic therapy of cervical cancer.

OBJECTIVES

Photodynamic therapy is one of the modern therapeutic techniques, in which cytotoxic effects are induced by light. Currently investigators show that it can be used to eliminate cervical cancer cells.

AIM: In this study we decided to check whether the Low Level Lasers Therapy (LLLT) can induce the phototoxic changes in HeLa cells, after their photosesitization.

MATERIAL AND

METHODS

The studies were performed in vitro on HeLa cervical cancer cell line. Protoporphyrin IX (PpIX) in final concentrations: 0.5, 1.0, 5.0 and 10.0 micromol/l was used as photosensitizer. The cells were preincubated with specific concentrations for 6 and 18 hours. After these defined periods of time the cultures were illuminated for 8 minutes by laser light (635 nm and 30 mW/cm2). The cytotoxic effects were assessed by a colorimetric test XTT, 24 and 48 hours after irradiation.

RESULTS

Significantly augmented cytotoxic changes were found in HeLa cells 18 hours after preincubation and 48 hours after illumination. Moreover, biostimulating laser exposure preceded by preincubation with protoporphyrin IX caused the cytotoxic changes in cervical cancer cells.

CONCLUSION

The obtained results allow us to assume that photodynamic therapy of cervical cancer using biostimulating laser light should be performed 18 hours after the application of protoporphyrin IX.