SI
SI
discoversearch

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor.  We ask that you disable ad blocking while on Silicon Investor in the best interests of our community.  If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.
Biotech / Medical : MGI Pharma MOGN New patents, anti cancer

 Public ReplyPrvt ReplyMark as Last ReadFilePrevious 10Next 10PreviousNext  
To: Icebrg who wrote (1523)10/7/2004 3:06:53 AM
From: Icebrg  Read Replies (1) of 1826
 
Cell Cycle Effects and Induction of Premitotic Apoptosis by Irofulven in Synchronized Cancer Cells.

Cancer Biol Ther. 2004 11 9; 3(11):
Woynarowski JM, Woynarowska BA, Trevino AV, Salinas R, Herman TS, Waters SJ, Macdonald JR

Unlike postmitotic cell death, direct premitotic apoptosis diminishes the risk of clonal selection and allows for the elimination of slowly growing cancer cells. This study characterized the ability to induce premitotic apoptosis by irofulven (hydroxymethylacylfulvene), a novel alkylating drug which targets cellular DNA and proteins. Irofulven effects were examined in HeLa-derived BH2 cancer cells with conditional overexpression of antiapoptotic Bcl-2. Cells were synchronized in either early S or in G(1). Following 12 h exposure to irofulven, cells that were originally in early S accumulated in late S or remained in early S phase (at 0.5 and 2.5 M drug, respectively). Drug treatment of cells in the G(1) cohort prevented their entry into the S phase. Significant apoptosis was detected based on the appearance of sub-G(1) particles and cells with DNA strand breaks in both G(1) and S cohorts. Apoptotic cells were mostly recruited from the G(1)/S border ("G(1)" cohort) and from the S phase ("early S" cohort). All the cell cycle and apoptotic effects were only marginally affected by Bcl-2 overexpression. Similar results were obtained with irofulven-treated synchronized cultures of leukemic CEM cells. Collectively, these observations indicate that irofulven-treated cells become committed to death early. Neither active DNA replication nor traverse through mitosis are necessary for irofulven-induced cell death. The ability to promote direct premitotic apoptosis is likely to play a role in the consistently potent apoptotic effects of irofulven and its ability to cause tumor regression in vivo.
Report TOU ViolationShare This Post
 Public ReplyPrvt ReplyMark as Last ReadFilePrevious 10Next 10PreviousNext