[Relationship between apoptosis induced by 2-butylamino-2-demethoxy-hypocrellin B in human pancreatic cancer cells Capan-1 and photosensitization of mitochondria].

OBJECTIVE

To explore the possible mechanism of apoptosis induced by photodynamic therapy (PDT) in human pancreatic cancer cells Capan-1 with 2-butylamino-2-demethoxy-hypocrellin B (BAHB) as photosensitizer.

METHODS

The localization of BAHB in Capan-1 cells was studied, apoptosis was determined by DNA gel electrophoresis after PDT. The mitochondria membrane potential (DYm) and cytochrome C release were observed by laser scan confocal microscopy and Western blotting.

RESULTS

The low concentration photosensitizer was mainly localized in mitochondria and also in lysosomes when the concentration is high. DNA ladder analysis showed characteristic of apoptosis. The mitochondria membrane potential (DYm) showed a loss of 30% around, after 6 hours by PDT under laser scan confocal microscopy, which is caused by a sudden increase in the permeability of mitochondria membrane accompanied with apoptosis. In Western blotting, cytochrome C release was observed from the mitochondria into the cytoplasm during BAHB-induced apoptosis.

CONCLUSION

The research suggests that BAHB-induced apoptosis is related to photosensitization of mitochondria.