The nucleoside analogue gemcitabine (2', 2-difluorideoxycytide) is potential against a wide variety of solid tumors and considered to be one of the most active drugs in the treatment of non-small cell lung cancer (NSCLC). In this study, we investigated the signals of gemcitabine-induced apoptosis, especially in point of caspase pathway in A549. We exposed A549 cells to gemcitabine for dose/time dependent manner and the results showed that gemcitabine induced apoptotic cell death in a time/dose-dependent manner. We also treated to gemcitabine and Z-VAD-fmk as a pan-caspase inhibitor for 24 hours.

Much of the interest on the chemopreventive properties of herbs and plants has been raised, whereas little is regarding to anti-tumor effect of farming and aquatic products. In the present study, the anti-tumor effect of hot-water extract of a seaweed, BLC (Sargassum fulvellum) and BLC/HEN egg was investigated using MCF-7 cells in vitro and in vivo systems. We found that the BLC extract and BLC/HEN egg inhibited cell proliferation in a dose-dependent manner, which might be mediated through up-regulation of p53. Furthermore, this test compound can directly induce apoptosis in MCF-7 cells, which might be mediated through up-regulation of a pro-apoptotic Bax protein and down-regulation of a anti-apoptotic Bcl-2 protein, not by immune system.

In the present study, we expected the anti-tumor effect by combined treatment of arsenic trioxide and interferon (IFN)-α on murine Lewis lung carcinoma (LL2) cells through in vivo study. As a experimental model, LL2 cells (1×10∨6/mouse) were injected subcutaneously into the back region of mice. When the tumor volume reached 100 ㎣, mice were treated with 1 mg/kg arsenic trioxide, 50000 IU IFN-α, or arsenic trioxide and IFN-α. The development of tumor cells was significantly inhibited by combined treatment with arsenic trioxide and IFN-α. In arsenic trioxide and IFN-α treated group, apoptotic index was reached a peak valve at 48 hr after the treatment and it was restored to approximately the control level at 8 days.

The irradiation of radioactive γ-ray induces apoptosis of radiosensitive organs for homeostasis. In this study, we investigated the repair mechanisms for homeostasis in the small intestine after cell damage by ∨60Co γ-ray irradiation. The apoptosis was most frequently observed in the crypt cells of the small intestine after four and six hours by radioactive γ-ray irradiation, and the frequency of apoptosis was proportional to the amount of irradiation. Also, the number of apototic cells was coincident with expression pattern of p53.

A cDNA clone encoding a prohibitin-like protein (Toprh) was isolated from a piroplasm cDNA library of Theileria orientalis and its nucleotide sequence was determined. An open reading frame, encoding a polypeptide of 278 amino acid residues, was found in Toprh cDNA sequence. An intron of 89 bp was identified when this cDNA clone was compared with the Toprh gene in the genome of T. orientalis. The deduced amino acid sequence of Toprh shares 93.8, 93.1 and 69.1% identities with the prohibitins of T. parva (from chromosome 1), T. annulata (from chromosome 1), and Plasmodium falciparum, (from chromosome 10), respectively. By Western blot analysis, Toprh was found to be expressed in the piroplasm stage of the parasites.