• The Korean Journal of Nuclear Medicine
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• v.38 no.2
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• pp.190-197
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• 2004

Apoptosis plays a role in the pathophysiology of many kinds of diseases and in the response of treatment. Compared to the necrosis, the apoptosis is a genetically controlled and energy-dependent process which removes the unwanted cells from the body; programmed cell death or cell suicide. During the apoptosis, phosphatidylserine is expressed in the cytoplasmic outer membrane in the early phase. Annexin V, an endogenous human protein (MW=35 kD), has an affinity of about $10^{-9}\;M$ for the phosphatidylserine exposed on the outer membrane of apoptotic cells. Annexin V can be radiolabeled with $^{99m}Tc$ by HYNIC or EC chelators, which can be used as an radiotracer for the in vivo imaging of apoptosis. In this article, we reviewed the apoptosis, radiolabeling of annexin V, and the experimental and clinical data using annexin V imaging.

• Journal of Nutrition and Health
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• v.36 no.4
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• pp.382-388
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• 2003

(-)-Epigallocatechin-3-gallate (EGCG) is a polyphenolic compound found in peen tea leaves, and has been known to be one of the most potent catechin species which inhibits cell growth most possibly through an apoptotic cell death. We investigated the apoptotic activity of (-)-EGCG on the human myeloid leukemia cell line, HL-60. Our results of MTT test indicated that (-)-EGCG had a significant antiproliferation effect in HL-60 cells with $IC_{50}$/ (50% inhibition concentration) value of 65 $\mu$M. Giemsa statining of HL-60 cells treated with (-)-EGCG (100 $\mu$M) for 6hrs showed a typical apoptosis-specific morphological change including shrinkage of the cytoplasm, membrane blobbing and compaction of the nuclear chromatin. The DNA fragmentation was observed from the agarose gel electrophoresis of cells treated with (-)-EGCG for 3hrs or longer, and was progressed to a greater degree as treatment time increases. Treatment of the cells with (-)-EGCG (100 $\mu$M) resulted in a rapid release of mitochondrial cytochrome c into the cytosol, and a subsequent cleavage of caspase-3 to an active form in a treatment-time dependent manner. (-)-EGCG (100 $\mu$M) also stimulated proteolytic cleavage of poly-(ADP-ribose) polymerase (PARP) to an active form in HL-60 cells. Tlken together, (-)-EGCG appears to induce the apoptosis in human myeloid leukemia cells via a caspase-dependent pathway. These results suggest the possible application of (-)-EGCG, the major active compound in green tea, as an antiproliferative agent for cancer prevention.

• Journal of Acupuncture Research
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• v.20 no.5
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• pp.93-106
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• 2003

Objective : To investigate the possible molecular mechanism(s) of melittin as a candidate of anti-cancer drug, we examined the effects of the compound on the growth of human lung carcinoma cell line A549. Methods: MTT, morphological changes, DAPI staining, Western blot, RT-PCR and in vitro prostaglandin E2 (PGE2) accumulation assays were performed. Results: The anti-proliferative effect by melittin treatment in A549 cells was associated with morphological changes such as membrane shrinking and cell rounding up. Melittin induced apoptotic cell death in a concentration-dependent manner, which was associated with inhibition or degradation of apoptotic target proteins such as ${\beta}$-catenin, poly(ADP-ribose) polymerase(PARP) and phospholipase $C-{\gamma}1(PLC-{\gamma}1)$. Melittin treatment inhibited the expression of cyclooxygenase-2(COX-2) and accumulation of PGE2 in aconcentration-dependent fashion. In addition, Melittin treatment induced the down-regulation of telomerase reverse transcriptase(hTERT) and proto-oncogene c-myc expression of A549 cells. Conclusions: Taken together, these findings suggest that melittin-induced inhibition of human lung cancer cell proliferation is associated with the induction of apoptotic cell death via regulation of several major growth regulatory gene products, and melittin may have therapeutic potential in human lung cancer.