Related Experiment Video
Updated: Aug 8, 2026

Detection of Inflammasome Activation and Pyroptotic Cell Death in Murine Bone Marrow-derived Macrophages
Published on: May 21, 2018
Proapoptotic activity of NAG-1 is cell type specific and not related to COX-2 expression
Tae Jung Jang1, Nam Ii Kim, Chang Hun Lee
1Department of Pathology, Dongguk University College of Medicine, Suek-jang Dong 707, Kyongju, Kyongbuk 780-714, Korea. taejung@mail.dongguk.ac.kr
Abstract:
Non-steroidal anti-inflammatory drugs (NSAIDs) activated gene (NAG-1) is a newly identified member of the transforming growth factor-beta (TGF-beta) superfamily. Members of the TGF-beta family are multifunctional growth factors, and the nature of their effects depends on the cellular context and cell type. NAG-1 has antitumorigenic and proapoptotic activities in colon and gastric cancer cells lacking endogenous cyclooxgenase-2 (COX-2) expression. In contrast, COX-2 overexpression is related to antiapoptotic activity. The purpose of this study is to evaluate the proapoptotic activity of NAG-1 according to COX-2 expression and cell type. NAG-1 cDNA was transfected in SNU668 cells with endogenous COX-2 expression, SNU601 cells with forced COX-2 expression and Hep3B hepatocellular carcinoma cells. SNU668 cells with ectopic expression of NAG-1 showed markedly elevated subG1 population, induced death receptor-4 (DR-4) and DR-5, and revealed smaller active fragments of caspase-3. Forced COX-2 expression in SNU601 cells did not inhibit apoptosis caused by NAG-1 expression. Sulindac sulfide caused apoptosis, and induced expression of DR-5 and NAG-1 in Hep3B cells. However, Hep3B cells ectopically expressing NAG-1 did not cause apoptosis, and smaller active fragments of caspase-3 and an 85 kDa band of poly ADP-ribose polymerase (PARP) did not appear in the transfected cells, either. This study suggests that proapoptotic activity of NAG-1 is cell type specific and not related to COX-2 expression.
Related Concept Videos
The Intrinsic Apoptotic Pathway
The Extrinsic Apoptotic Pathway
Apoptosis
Caspases
Autophagic Cell Death
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and pro-apoptotic...
Necrosis
Morphological Manifestations of Necrosis
Necrotic cells show different types of morphological appearance depending on the type of tissue and infection. In coagulative necrosis, cells become anucleated and die, but their...

