Evaluation of molecular mechanisms of tumor-specific protoporphyr in accumulation induced by 5-aminolevulinic acid

5-氨基酮戊酸是最有效的光动力治疗药物之一，因为它诱导肿瘤细胞特异性的光敏剂原卟啉IX(PPIX)在细胞内积聚。然而，5-ALA诱导PPIX积聚的分子机制仍不清楚。在本研究中，为了建立预测光动力疗法治疗癌症的疗效的依据，我们研究了5-ALA诱导不同的人癌细胞系在5-ALA作用下PPIX积聚的分子机制。结果表明，PPIX的积累可能是由PPIX的生物合成、铁络合酶(FECH)活性和PPIX外流决定的。

5-Aminolevulinic acid is one of the most potent photodynamic therapeutic agents, because it induces tumor cell-specific intracellular accumulation of a photosensitizer, protoporphyrin IX (PPIX). However, molecular mechanisms of such 5-ALA-induced PPIX accumulation remain unclear. In the current study, in order to establish a basis to predict efficacy of photodynamic therapy to treat cancer, molecular mechanisms of intracellular accumulation of PPIX induced by 5-ALA were studied in various human cancer cell lines exposed to 5-ALA. Results suggested that PPIX accumulation is likely determined by PPIX biosynthesis, ferrochelatase (FECH) activity and PPIX efflux.