지금초 추출물에 의한 TRAIL 저항성 인체위암세포의 세포사멸 유도

국문 초록 (Abstract)

본 연구에서는 지금초 열수 추출물(WEEH)의 처리에 의한 TRAIL 저항성 인체 위암세포의 증식 억제와 연관된 apoptosis 유발에 관한 기전 해석을 시도하였다. 이를 위하여 AGS 세포주가 사용되었으며 다음과 같은 결과를 얻었다. 본 연구에서 조사된 범위 내에서의 TRAIL (200 ng/㎖) 및 WEEH (0.04 ㎎/㎖)의 단독 처리에 의한 AGS 세포에 유의적인 세포 독성을 나타내지 않았다. 그러나 TRAIL 및 WEEH의 혼합 처리는 WEEH의 처리 농도의존적으로 AGS세포의 증식을 억제하였으며, 이는 apoptosis 유발에 의한 것임을 MTT assay, 핵의 염색질 응축 및 세포주기 sub-G1기에 속하는 세포빈도의 증가 등으로 확인하였다. TRAIL 및 WEEH 혼합 처리에 의한 apoptosis 유발 기전의 해석을 위하여 다양한 생화학적 분석법에 의하여 조사된 결과에 의하면, TRAIL 및 WEEH 혼합처리에 의한 caspase-8의 활성화에 의한 BID의 truncation화 및 이와 연관된 미토콘드리아 기능의 손상에 따른 caspase-9의 활성화와 연관성이 있었다. 이러한 미토콘드리아 기능 손상 및 caspase-9의 활성화는 Bcl-2, Bcl-xL, XIAP 및 cIAP-2 등과 같은 anti-apoptotic 인자들의 발현 저하와 연관성이 있는 것이며, 이로 인한 caspase-3의 활성화에 의한 PARP 단백질의 단편화 유도로 apoptosis가 일어난 것으로 예측되어 진다. 비록 부가적인 연구들이 요구되어지지만, 본 연구의 결과는 TRAIL 저항성 암세포의 항암전략에 지금초 추출물의 적용 가능성을 보여주는 것으로서 지금초의 항암작용의 규명에 중요한 자료를 제공하여 줄 것으로 생각된다.

다국어 초록 (Multilingual Abstract)

The death ligand tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)/ Apo1L is a cytokine that activates apoptosis through cell surface death receptors. TRAIL has sparked growing interest in oncology due to its reported ability to selectively trigger cancer cell death. Euphorbiae humifusae Wind has been used in traditional Oriental medicine as a folk remedy used for the treatment of cancer. However, the mechanism responsible for the anticancer effects of E. humifusae not clearly understood. Here, we show that treatment with subtoxic doses of water extract of E. humifusae (WEEH) in combination with TRAIL induces apoptosis in TRAIL-resistant human gastric carcinoma AGS cells. Combined treatment with WEEH and TRAIL induced chromatin condensation and sub-G1 phase DNA content. These indicators of apoptosis were correlated with the induction of caspase activity that resulted in the cleavage of poly (ADP-ribose) polymerase. Combined treatment also triggered the loss of mitochondrial membrane potential. Furthermore, co-treatment with WEEH and TRAIL down-regulated the protein levels of the anti-apoptotic proteins such as Bcl-2, Bcl-xL, XIAP and cIAP-1. Although more study will be needed to examine the detailed mechanisms, this combined treatment may offer an attractive strategy for safely treating gastric adenocarcinomas and the results provide important new insights into the possible molecular mechanisms of the anticancer activity of E. humifusae.

목차 (Table of Contents)

• 서론
• 재료 및 방법
• 결과
• 고찰
• 요약
• References

참고문헌 (Reference)

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