title: Novel development of 5-aminolevurinic acid (ALA) in cancer diagnoses and therapy.
abstract: Early detection and intervention are needed for optimal outcomes in cancer therapy. Improvements in diagnostic technology, including endoscopy, photodynamic diagnosis (PDD), and photodynamic therapy (PDT), have allowed substantial progress in the treatment of cancer. 5-Aminolevulinic acid (ALA) is a natural, delta amino acid biosynthesized by animal and plant mitochondria. ALA is a precursor of porphyrin, heme, and bile pigments, and it is metabolized into protoporphyrin IX (PpIX) in the course of heme synthesis. PpIX preferentially accumulates in tumor cells resulting in a red fluorescence following irradiation with violet light and the formation of singlet oxygen. This reaction, utilized to diagnose and treat cancer, is termed ALA-induced PDD and PDT. In this review, the biological significance of heme metabolites, the mechanism of PpIX accumulation in tumor cells, and the therapeutic potential of ALA-induced PDT alone and combined with hyperthermia and immunotherapy are discussed.
authors.affiliation: SBI ALApromo Co, LTD Roppongi 1-6-1, Minato-ku, Tokyo 106-6019, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ishizuka
authors.forename: Fuminori
authors.initials: F
authors.lastname: Abe
authors.forename: Yuki
authors.initials: Y
authors.lastname: Sano
authors.forename: Kiwamu
authors.initials: K
authors.lastname: Takahashi
authors.forename: Katsushi
authors.initials: K
authors.lastname: Inoue
authors.forename: Motowo
authors.initials: M
authors.lastname: Nakajima
authors.forename: Takeo
authors.initials: T
authors.lastname: Kohda
authors.forename: Naoki
authors.initials: N
authors.lastname: Komatsu
authors.forename: Shun-ichiro
authors.initials: S
authors.lastname: Ogura
authors.forename: Tohru
authors.initials: T
authors.lastname: Tanaka
mesh_terms: D000622:Aminolevulinic Acid / Q000737:chemistry / Q000494:pharmacology*; D006418:Heme / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D015394:Molecular Structure; D009369:Neoplasms / Q000175:diagnosis* / Q000188:drug therapy*; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D017319:Photosensitizing Agents; D006418:Heme; D000622:Aminolevulinic Acid