A non-laser light source for photodynamic therapy: in vitro effects on normal and malignant cells.
OBJECTIVE
Photodynamic therapy (PDT) involves the use of photosensitizing drugs combined with light to treat tumors. Laser systems, the current source of light for PDT, have several inherent drawbacks: the spectrum is essentially monochromatic which may be problematic for second generation photosensitizers, the systems are bulky and nearly impossible to move between hospital locations and require complicated electrical and cooling installations, the cost of a typical system is enormous, and its maintenance and operation require highly trained personnel. We now introduce a new non-laser light system, Versa-Light, which appears to work as effectively and has none of the above drawbacks.


METHODS
A series of in vitro studies were performed using various murine and human normal and cancer cells which underwent PDT using aluminum phthalocyanine (AlPcS4) as a photosensitizer and Versa-Light as the light source.


RESULTS
PDT of cancer cells at light energy levels of 50, 100 and 200 j/cm2 significantly decreased cell viability. PDT also decreased cell viability of normal murine splenocytes and normal human lymphocytes, but to a lesser extent. The observed significant hyperthermia was light dose-dependent.


CONCLUSIONS
We believe that Versa-Light can replace laser systems as an enhanced light source for PDT. Further in vitro and pre-clinical studies are in progress.
Kashtan
Hanoch
H
Department of Surgery A, Tel-Aviv Medical Center, Tel-Aviv, Israel. hkashtan@clalit.org.il
Haddad
Riad
R
Greenberg
Ron
R
Skornick
Yehuda
Y
Kaplan
Ofer
O
D000818:Animals; D003110:Colonic Neoplasms / Q000188:drug therapy; D005260:Female; D005336:Fiber Optic Technology / Q000295:instrumentation; D006801:Humans; D066298:In Vitro Techniques; D007211:Indoles / Q000627:therapeutic use; D020014:K562 Cells; D008027:Light; D008546:Melanoma, Experimental / Q000188:drug therapy; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000188:drug therapy*; D009942:Organometallic Compounds / Q000627:therapeutic use; D010778:Photochemotherapy / Q000295:instrumentation / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use; D014407:Tumor Cells, Cultured; D014978:Xenon
D007211:Indoles; D009942:Organometallic Compounds; D017319:Photosensitizing Agents; C048577:aluminum tetrasulfophthalocyanine; D014978:Xenon