Morphological changes of apoptosis in the human cholangiocarcinoma cell line, HuCCA-1, induced by green pit viper venom.

The venom of the green pit viper (Trimeresurus purpureomaculatus) was used to study the effect on bile duct epithelial cancer cell damage, using the human cholangiocarcinoma cell line, HuCCA-1, as a model. After cell treatment by various concentrations of snake venom at different times, alteration of the cellular structure was observed, especially in the apoptosis of cells. Under a light microscope, many patterns of cellular changes were obvious following treatment with 40 ∝g/ml snake venom for six h, while the structure of untreated cells was still unchanged. The number of altered cells was significantly higher than in the control (p<0.05). A transmission electron micrograph showed that venom-treated cells had the characteristic of apoptosis to varying degrees. The cells presented plasma membrane blebs, an increased number of cytoplasmic vacuoles, enlargement or deterioration of organelles, reduced nuclear size, irregular nuclear membrane and clumping of nuclear chromatin. Though snake venom in the Viperidae family causes hemorrhagic symptoms by the function of several components, including phospholipase A2, it was hypothesized that the venom of the green pit viper shared structural similarity with Lys49 phospholipase A2, which lacked a hemolytic activity, but showed an ability to induce cancer cell apoptosis.