KOREASCHOLAR

Apoptos is s ignal- regulating kinase 1 (ASKl) is a rnitogen-activated protein kinase kinase kinase(MAP3K) 떼 th proapoptotic functlOn 1'he kinase activity of ASKl is stimulated by a variety of death signals , including 1'NFα • Fas ligation, reactive oxygen species, and antineoplastic agents, ASKl promotes cell death by activating the c- Jun N-termina l kinase/stress-activated protein kinase MKK4/MKK7-JNK/SAPK pathway and MKK3/ 1\αCK6-p38 pathway‘ ASKl activity is highly controlled in cells by multiple mechanisms, including phosphorylation, oligome ri zation, and protein- protein ll1 teractlOns Epigallocatechin-3-galla te(EGCG) is the major bioactive polyphenol present in green tea, It possesses anti-oxida nt , a nti - mutagenic‘ a n ti - prote이 ytic ， and anti-proliferative activity, In addition. it has been shown to inhibit cyclin activity, and inhibit cell cycle progression 1n the present study, we exarnined the effect of EGCG on ASKl- overexpressed cells , We expected that EGCG contributes to cell a poptos is by activating ASKl functlOn However, EGCG showed no suppressive effect on cell s urvival of ASKl-overexpressed cells and seemed to promote cell survlval Importantly, the EGCG treatment in creased Akt activity when cells expressed enough amount of ASKl protein, These results s uggest that the presence of ASKl may modify the inhibitory effect of EGCG on cell survival through Akt pathway,

• Kyung Ah Kim(Department of Oral & Maxillofacial Pathology,school of Dentistry, Pusan National University)
• Voki Woo(Department of Oral & Maxillofacial Pathology,school of Dentistry, Pusan National University)
• Hae Ryoun Park(Department of Oral & Maxillofacial Pathology,school of Dentistry, Pusan National University)