Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.22.62 (caspase-9)
 7,507 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Matrine is a major component of Sophora Flavescens and has been reported to stimulate differentiation of erythroleukemia cells. Here we show that matrine inhibits cell proliferation or induces apoptosis in a cell type-specific manner. The latter effect was investigated in more detail in the p53 deficient erythroleukemia cell line, K562. Matrine exposure induced apoptosis in a time- and dose-dependent manner in these cells. Interestingly, co-treatment with etoposide potentiated apoptosis. Further analysis of matrine-induced apoptotic changes revealed that E2F-1 and Apaf-1 were upregulated, whereas Rb was downregulated after 24 h of exposure. This was followed by Bax translocation, cytochrome c release, and caspase-9 and -3 activation. These results demonstrate that matrine triggers apoptosis of K562 cells primarily through the mitochondrial pathway and that matrine is a potential anti-tumor drug.
 ...
PMID:Matrine upregulates the cell cycle protein E2F-1 and triggers apoptosis via the mitochondrial pathway in K562 cells. 1729 88

Diosgenin is a plant steroid which is able to induce megakaryocytic differentiation of human erythroleukemia (HEL) cells followed by apoptosis at a later stage. Apoptosis markers and phospho-kinases involved during the subsequent apoptosis of megakaryocytes after diosgenin-induced differentiation in these cells were detected using a proteomic approach. In mature megakaryocytes undergoing apoptosis, we observed increased expression of intrinsic apoptosis markers such as Bax/Bcl-2 ratio and cleaved caspase-9 as well as extrinsic apoptosis markers including cell death receptors and cleaved caspase-8. Furthermore, we demonstrated the link between both apoptotic pathways by Bid cleavage and confirmed the executive phase of apoptosis by caspase-3 cleavage. For the first time, we examined kinase activation and showed that kinases including Src, Tor, Akt, CREB, RSK and Chk2 may be implicated in signalling of subsequent apoptosis of mature megakaryocytes after diosgenin-induced differentiation of HEL cells.
 ...
PMID:A proteomic approach to the identification of molecular targets in subsequent apoptosis of HEL cells after diosgenin-induced megakaryocytic differentiation. 1941 84

We examined whether betulin, a naturally abundant compound, has anticancer functions in human cancer cells. The results showed that betulin significantly inhibited cell viability in cervix carcinoma HeLa cells, hepatoma HepG2 cells, lung adenocarcinoma A549 cells, and breast cancer MCF-7 cells with IC(50) values ranging from 10 to 15 microg/mL. While betulin exhibited only moderate anticancer activity in other human cancer cells such as hepatoma SK-HEP-1 cells, prostate carcinoma PC-3, and lung carcinoma NCI-H460, with IC(50) values ranging from 20 to 60 microg/mL, it showed minor growth inhibition in human erythroleukemia K562 cells (IC(50) > 100 microg/mL). We further investigated the mechanism of anticancer activity by betulin, using HeLa cells as an experimental model. Betulin (10 microg/mL) induces apoptotic cell death, as evidenced by morphological characteristics such as membrane phosphatidylserine translocation, nuclear condensation/fragmentation, and apoptotic body formation. A kinetics analysis showed that the depolarization of mitochondrial membrane potential and the release of mitochondrial cytochrome c occurred as early as 30 min after treatment with betulin. Betulin, unlike its chemical derivative betulinic acid, did not directly trigger mitochondrial cytochrome c release in isolated mitochondria. Importantly, Bax and Bak were rapidly translocated to the mitochondria 30 min after betulin treatment. The sequential activation of caspase-9 and caspase-3/-7 and the cleavage of poly(ADP-ribose) polymerase (PARP) were observed behind those mitochondrial events. Furthermore, specific downregulation of either caspase-9, Bax, or Bak by siRNA effectively reduced PARP cleavage and caspase-3 activation. Taken together, the lines of evidence demonstrate that betulin triggers apoptosis of human cancer cells through the intrinsic apoptotic pathway.
 ...
PMID:Betulin induces mitochondrial cytochrome c release associated apoptosis in human cancer cells. 2056 40