13 результати
Defects in apoptosis signaling pathways contribute to tumorigenesis and drug resistance, and these defects are often a cause of failure of chemotherapy. Thus, a major goal in chemotherapy is to find cytotoxic agents that restore the ability of tumor cells to undergo apoptosis. We previously found
Caracasine acid (CA) is an ent-3,4-seco-kaurene isolated from the plant Croton micans. Decreased cancer cell lines viability was reported upon CA treatment. The present study aimed to investigate the mechanism of CA induced cytotoxicity using two human cell lines, Jurkat E6.1 (human cell T lymphoma)
Some antitumor agents, including tumor necrosis factor-alpha (TNF-alpha) and camptothecin (CPT), often cause resistance of tumor cells to antitumor agents through activation of the nuclear factor-kappa B (NF-kappa B) pathway that leads to up-regulation of anti-apoptotic proteins. Therefore,
A novel 14,20-epoxy-ent-kaurene diterpenoid, excisanin H (1), and three new ent-kaurene diterpenoids, 2-4, were isolated from aerial parts of Rabdosia excisa along with eight known ent-kaurene diterpenoids, 5-12. The structural elucidations were made using spectral (HREIMS, IR, (1)H, (13)C, and 2D
Two new ent-kaurene-type and a new rearranged ent-kaurene-type diterpenoids possessing cytotoxicity against a human leukemia cell line have been isolated from the New Zealand liverwort Jungermannia species, together with previously known ent-kaurene-type diterpenoids. Their structures were
We previously reported that ent-11alpha-hydroxy-16-kauren-15-one (KD) induces apoptosis through a caspase-dependent pathway and the induction of apoptosis is dependent on its enone group in human leukemia cells. Here we investigated the abilities of some KD-related compounds with enone group (Fig.
Kaurene-type diterpenes possess various biological activities including antitumor and anti-inflammatory effects. Indeed, we have found that an ent-kaurene diterpene, ent-11alpha-hydroxy-16-kauren-15-one (KD), induced apoptosis via caspase-8 activation in human promyelocytic leukemia HL-60 cells.
Some diterpenoids show various biological activities, including anti-inflammatory, anti-HIV and anti-tumor activity. Previously, we have focused our research on the apoptosis-inducing properties of diterpenoids and found that some ent-kaurene-type diterpenoids induced apoptosis in human leukemia
In this study, we report the functional characterization of a new ent-kaurene diterpenoid termed pharicin A, which was originally isolated from Isodon, a perennial shrub frequently used in Chinese folk medicine for tumor treatment. Pharicin A induces mitotic arrest in leukemia and solid
Ent-11alpha-hydroxy-16-kauren-15-one (1) induced apoptosis in a human leukemia cell line (HL-60 cells), however, the apoptosis-inducing properties of 1 and its related compounds remain to be proved. We examined the involvement of caspases, a family of cysteine aspartic proteases, which play a
1-O-Monoacyl, 12-O-monoacyl, 1-,12-O-diacyl, and 11,12-dehydrated excisanin A 7,14-acetonides were synthesized from excisanin A isolated from Rabdosia excisa. The structure and cytotoxic activity relationships (SAR) of the natural parent ent-kaurene diterpenes and these semisynthetic analogues were
Rabdosia japonica has been historically used in China as a popular folk medicine for the treatment of cancer, hepatitis, and gastricism. Glaucocalyxin A (GLA), an ent-kaurene diterpene isolated from Rabdosia japonica, is one of the main active ingredients showing potent inhibitory All-trans retinoic acid (ATRA), a natural ligand for the retinoic acid receptors (RARs), induces clinical remission in most acute promyelocytic leukemia (APL) patients through the induction of differentiation and/or eradication of leukemia-initiating cells. Here, we identify a novel natural