Photodynamic therapy (
PDT) has become a promising option for the treatment of head and neck, and other forms of
cancer. 5-Aminolevulinic
acid (ALA) is one of the popular
photosensitizers used in
PDT. It is a
heme precursor and is converted to a
photosensitizer protoporphyrin IX. In this present study, the combination of anticancer
drug cisplatin (CDDP)- and ALA- mediated
PDT was used to study the cytotoxicity in vitro as well as in vivo. Human
head and neck cancer cells AMC-HN3 were treated with
cisplatin- and ALA-mediated
PDT individually, and also in combination. Several approaches like confocal microscopic study, cytotoxicity assay, etc have been performed to study the intracellular accumulation of protophorphyrin IX in cells and its effectiveness in
PDT, when treated in combination with
chemotherapy drug,
cisplatin (CDDP). The combination of treatments efficacy was also studied in
tumor xenograft model. Compared to the individual treatments, combination of CDDP and
PDT was found to be more cytotoxic in AMC-HN3, and also more effective in reducing the
tumor volume in mice xenograft. Thus, with the combined
therapy, not only the efficacy of treatment can be enhanced, but the doses of the drugs can also be lowered. This in turn can reduce the side effects of the
chemotherapy drugs. Therefore, this study may lead to a potential
drug-
PDT combination that may be a useful treatment modality for human
head and neck cancer.