Photodynamic therapy (PDT) uses photosensitizer activation by light of a specific wavelength, and is a promising treatment for various cancers; however, the detailed mechanism of PDT remains unclear. Therefore, we investigated the anticancer effect of PDT using a novel phosphorus tetraphenylporphyrin (Ptpp) in combination with light emitting diodes (Ptpp-PDT) in the NOZ human biliary cancer cell line. Cell viability and apoptosis were examined by MTT assay, flow cytometry and TUNEL assay for 24 hr after Ptpp-PDT. MitoTracker and JC-1 were used as markers of mitochondrial localization and membrane potential. The levels of mitochondrial oxidative phosphorylation (OXPHOS) complexes, Bcl-2 family proteins, cytochrome c and cleaved caspase-3 were examined by western blotting and immunohistochemistry. The results revealed that Ptpp localized to mitochondria, and that Ptpp-PDT efficiently decreased cell viability in a dose- and time-dependent manner. JC-1 and OXPHOS complexes decreased, but apoptotic cells increased from 6 to 24 hr after Ptpp-PDT. A decrease in Bcl-xL and increases in Bax, cytochrome c and cleaved caspase-3 were also found from 6 to 24 hr after Ptpp-PDT. Based on these results, we conclude that Ptpp-PDT induces anticancer effects via the mitochondrial apoptotic pathway by altering the Bax/Bcl-xL ratio, and could be an effective treatment for human biliary cancer.

光动力疗法（PDT）利用特定波长的光激活光敏剂，是治疗各种癌症的有前途的疗法。但是，PDT的详细机制仍不清楚。因此，我们研究了新型磷四苯基卟啉（Ptpp）与发光二极管（Ptpp-PDT）结合使用在NOZ人胆道癌细胞系中对PDT的抗癌作用。在Ptpp-PDT后24小时，通过MTT测定，流式细胞术和TUNEL测定检查细胞活力和凋亡。MitoTracker和JC-1用作线粒体定位和膜电位的标记。通过蛋白质印迹和免疫组织化学检查线粒体氧化磷酸化（OXPHOS）复合物，Bcl-2家族蛋白，细胞色素c和裂解的胱天蛋白酶3的水平。结果表明，Ptpp定位于线粒体，而Ptpp-PDT有效地降低了细胞活力，呈剂量和时间依赖性。在Ptpp-PDT后6至24小时，JC-1和OXPHOS复合物减少，但凋亡细胞增加。在Ptpp-PDT后6到24小时，还发现Bcl-xL降低，Bax，细胞色素c和裂解的caspase-3升高。基于这些结果，我们得出结论，Ptpp-PDT通过改变Bax / Bcl-xL比，通过线粒体凋亡途径诱导抗癌作用，并且可能是治疗人类胆道癌的有效方法。Ptpp-PDT后6至24小时也发现了细胞色素c和裂解的caspase-3。基于这些结果，我们得出结论，Ptpp-PDT通过改变Bax / Bcl-xL比，通过线粒体凋亡途径诱导抗癌作用，并且可能是治疗人类胆道癌的有效方法。Ptpp-PDT后6至24小时也发现了细胞色素c和裂解的caspase-3。基于这些结果，我们得出结论，Ptpp-PDT通过改变Bax / Bcl-xL比，通过线粒体凋亡途径诱导抗癌作用，并且可能是治疗人类胆道癌的有效方法。