Abstract: | Photodynamic therapy (PDT) is a kind of photochemo therapeutic treatment that exerts its effect mainly through the induction
of cell death. Distinct types of cell death may be elicited by different PDT regimes. In this study, efforts are underway
to optimize PDT protocols for improved efficacy and combination of all three PDT mechanisms involved in the different human
carcinomas cell narcosis. Our in vitro cell culture experiments with 5-aminolevulanic acid (ALA) a clinically approved photiosensitizer
(PS) and 635 nm laser light have yielded promising results, as follow: (1) (human cervical cancer (HeLa) cell line incubated,
for 18 h, with 30 μg/ml of 5-ALA, treated with laser light dose of 50 J/cm2 can produce 85% of cell killing (2) human larynx carcinoma (Hep2c) cell line incubated, for 7 h, with 55 μg/ml of 5-ALA,
treated with laser light dose of 85 J/cm2 can produce 75% of cell killing (3) human liver cancer (HepG2) cell line incubated, for 22–48 h, with 262 μg/ml of 5-ALA,
treated with laser light dose of 120 J/cm2 can produce 95% of cell killing (4) human muscle cancer (RD) cell line incubated, for 47 h, with 250 μg/ml of 5-ALA, treated
with laser light dose of 80 J/cm2 can produce 76% of cell killing (5) Human embryonic kidney (HEK293T) cell line incu-bated, for 18 h, with 400 μg/ml of 5-ALA,
treated with laser light dose of 40 J/cm2 can produce 82% of cell killing confirming the efficacy of photodynamic therapy. |