PMID- 19345744
OWN - NLM
STAT- MEDLINE
DCOM- 20090923
LR  - 20221207
IS  - 0006-3002 (Print)
IS  - 0006-3002 (Linking)
VI  - 1791
IP  - 8
DP  - 2009 Aug
TI  - Downregulation of neutral ceramidase by gemcitabine: Implications for cell cycle 
      regulation.
PG  - 730-9
LID - 10.1016/j.bbalip.2009.03.012 [doi]
AB  - Gemcitabine (GMZ) is a chemotherapeutic agent with well established effects on 
      cell growth arrest and apoptosis. In this study, we investigated the potential 
      roles of bioactive sphingolipids in mediating the growth suppressing effects of 
      GMZ on a polyoma middle T transformed murine endothelial cell line. After 12-hour 
      GMZ (0.6 microM) treatment, cell growth was arrested at the G(0)/G(1) phase as 
      detected by flow cytometric cell cycle analysis and MTT cell viability analysis, 
      and this was accompanied by dephosphorylation of the retinoblastoma protein (Rb). 
      Furthermore, GMZ treatment resulted in increased levels of specifically the very 
      long chain ceramides as determined by mass spectrometry. Mechanistically, GMZ did 
      not appear to affect the activities of many enzymes of ceramide metabolism; 
      however, GMZ caused a selective reduction in the protein levels of neutral 
      ceramidase (NCDase), as indicated by Western blot analysis, with a concomitant 
      decrease in NCDase activity. The significance of NCDase loss on cell cycle 
      regulation was investigated by specific knockdown of the enzyme using small 
      interfering RNA (siRNA). Interestingly, NCDase siRNA transfection was sufficient 
      to induce a cell cycle arrest at G(0)/G(1) and an increase in total ceramide 
      levels, with significant elevation in very long chain ceramides (C(24:1) and 
      C(24:0)). NCDase siRNA also induced Rb dephosphorylation. These data provide 
      evidence for a novel mechanism of action for GMZ and highlight downregulation of 
      NCDase as a critical step in GMZ-mediated ceramide elevation and cell cycle 
      arrest.
FAU - Wu, Bill X
AU  - Wu BX
AD  - Department of Biochemistry and Molecular Biology, Medical University of South 
      Carolina, Charleston, 29425, USA.
FAU - Zeidan, Youssef H
AU  - Zeidan YH
FAU - Hannun, Yusuf A
AU  - Hannun YA
LA  - eng
GR  - GM43825/GM/NIGMS NIH HHS/United States
GR  - R01 GM043825/GM/NIGMS NIH HHS/United States
GR  - P01 CA097132-06/CA/NCI NIH HHS/United States
GR  - R01 CA087584/CA/NCI NIH HHS/United States
GR  - R01 CA087584-09/CA/NCI NIH HHS/United States
GR  - R37 GM043825/GM/NIGMS NIH HHS/United States
GR  - P01 CA097132/CA/NCI NIH HHS/United States
GR  - CA87584/CA/NCI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
DEP - 20090402
PL  - Netherlands
TA  - Biochim Biophys Acta
JT  - Biochimica et biophysica acta
JID - 0217513
RN  - 0 (Ceramides)
RN  - 0 (RNA, Small Interfering)
RN  - 0 (Retinoblastoma Protein)
RN  - 0W860991D6 (Deoxycytidine)
RN  - EC 3.1.4.12 (Sphingomyelin Phosphodiesterase)
RN  - EC 3.5.1.23 (Neutral Ceramidase)
RN  - 0 (Gemcitabine)
SB  - IM
MH  - Animals
MH  - Cell Cycle/*drug effects
MH  - Cell Line
MH  - Ceramides/metabolism
MH  - Deoxycytidine/*analogs & derivatives/pharmacology
MH  - Down-Regulation/*drug effects
MH  - Endothelial Cells/*cytology/drug effects/*enzymology
MH  - Gene Knockdown Techniques
MH  - Mice
MH  - Neutral Ceramidase/*metabolism
MH  - Phosphorylation/drug effects
MH  - RNA, Small Interfering/metabolism
MH  - Retinoblastoma Protein/metabolism
MH  - Sphingomyelin Phosphodiesterase/metabolism
MH  - Gemcitabine
PMC - PMC2788435
MID - NIHMS107510
EDAT- 2009/04/07 09:00
MHDA- 2009/09/24 06:00
PMCR- 2010/08/01
CRDT- 2009/04/07 09:00
PHST- 2008/11/19 00:00 [received]
PHST- 2009/02/24 00:00 [revised]
PHST- 2009/03/17 00:00 [accepted]
PHST- 2009/04/07 09:00 [entrez]
PHST- 2009/04/07 09:00 [pubmed]
PHST- 2009/09/24 06:00 [medline]
PHST- 2010/08/01 00:00 [pmc-release]
AID - S1388-1981(09)00086-9 [pii]
AID - 10.1016/j.bbalip.2009.03.012 [doi]
PST - ppublish
SO  - Biochim Biophys Acta. 2009 Aug;1791(8):730-9. doi: 10.1016/j.bbalip.2009.03.012. 
      Epub 2009 Apr 2.