Abstract
The spen-nine analogue N-1,N-11-diethylnorspermine (DENSPM) efficiently depletes the cellular pools of putrescine, spermidine and spermine by down-regulating the activity of the polyamine biosynthetic enzymes and up-regulating the activity of the catabolic enzyme spermidine/spermine N-1-acetyltransferase (SSAT). In the breast cancer cell line L56Br-Cl. treatment with 10 muM DENSPM induced SSAT activity 60 and 240-fold at 24 and 48 h after seeding. respectively, which resulted in polyamine depletion. Cell proliferation appeared to be totally inhibited and within 48 h of treatment, there was an extensive apoptotic response. Fifty percent of the cells were found in the sub-G(1) region, as determined by flow cytometry, and the presence of apoptotic nuclei was morphologically assessed by fluorescence microscopy. Caspase-3 and caspase-9 activities were significantly elevated 24 h after seeding, At 48 h after seeding, caspase-3 and caspase-9 activities were further elevated and at this time point a significant activation of caspase-8 was also found. The DENSPM-induced cell death was dependent on the activation of the caspases as it was inhibited by the general caspase inhibitor Z-Val-Ala-Asp fluoromethyl ketone. The results are discussed in the fight of the L56Br-Cl cells containing mutated BRCA1 and p53, two genes involved in DNA repair.
Original language | English |
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Pages (from-to) | 1033-1039 |
Journal | European Journal of Biochemistry |
Volume | 269 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2002 |
Subject classification (UKÄ)
- Cancer and Oncology
Free keywords
- N-11-diethylnorspermine
- N-1
- DNA fragmentation
- caspase
- apoptosis
- breast cancer cells