Over-expression 5-aminolevulinic acid synthase 2 in nonerythroid cell may causes protoporphyrin IX accumulation

Protoporphyrin IX (PpIX) has been used as an efficient sensitizer in photodynamic diagnose, photodynamic therapy, and sonodynamic therapy. The level of PpIX is very important for diagnose or therapy effects. 5-aminolevulinic acid synthase 2 (ALAS2) is the key enzyme upstream of PpIX synthesis. To increase PpIXaccumulation, ALAS2 overexppression transgenic mice were generated. Plasmid containing alas2 gene was transfected in colonic carcinoma cell lines. Both in tissues of transgenic mice and in colonic carcinoma cells, the amount of PpIXaccumulation did increased. At the meanwhile, level of heme, which down stream of PpIX had not been changed. Overexpression ALAS2 in nonerythriod cells may become a novel approach to cause PpIX accumulation.