PMID- 22972540
OWN - NLM
STAT- MEDLINE
DCOM- 20130514
LR  - 20171116
IS  - 1536-3694 (Electronic)
IS  - 0163-4356 (Linking)
VI  - 34
IP  - 5
DP  - 2012 Oct
TI  - Establishment of thiopurine S-methyltransferase gene knockdown in jurkat 
      T-lymphocytes: an in vitro model of TPMT polymorphism.
PG  - 584-92
LID - 10.1097/FTD.0b013e31826ec4b4 [doi]
AB  - BACKGROUND: Thiopurine S-methyltransferase (TPMT) is an excellent example of an 
      enzyme whose pharmacogenetic polymorphisms affect efficacy and toxicity of a 
      drug. The association between TPMT activity and thiopurine-related 
      myelosuppression is well recognized. To study the significance of TPMT deficiency 
      in thiopurine metabolism and immunosuppressive activity in vitro, we established 
      RNA interference-based TPMT knockdown (kd) in a Jurkat cell line. RESULTS: In 
      Jurkat TPMT kd cells, TPMT expression was reduced to 73% at the RNA level and 83% 
      at the protein level. TPMT kd cells were more sensitive to 6-mercaptopurine 
      (6-MP) (10 mumol/L) and 6-thioguanine (6-TG) (8 mumol/L) than wild-type (wt) cells, 
      (32% versus 20%) and (18% versus 9%), respectively. Both Jurkat wt and kd cells 
      were more sensitive to 6-TG-induced apoptosis than to 6-MP. 6-TG activity was 
      also more affected by TPMT levels than was 6-MP as reflected by IC60, 
      concentrations that is, 6-MP [4.6 mumol/L (wt) and 4.7 mumol/L (kd)], 6-TG [2.7 
      mumol/L (wt) and 0.8 mumol/L (kd)]. IC60 concentrations induced significant 
      apoptosis in both Jurkat wt and kd cells (257%, versus 314%) with 6-MP and (323% 
      versus 306%) with 6-TG, respectively. At IC60 (6-MP) 6-thioguanine nucleotides 
      (6-TGN) accumulation in cells was 518 versus 447 pmol/million cells in wt and kd 
      cells, respectively. On the other hand 6-TGN accumulation at IC60 (6-TG) was 477 
      versus 570 pmol/million cells in wt and kd cells, respectively. 6-Methylated 
      mercaptopurine (6-MeMP) concentrations were more affected than 6-TGN by TPMT kd 
      (194 versus 10 pmol/million cells) in wt and kd cells, respectively. CONCLUSION: 
      We conclude that TPMT kd cells are an appropriate in vitro model to investigate 
      the significance of TPMT deficiency with thiopurine therapy and could be helpful 
      in understanding possible clinical consequences of TPMT polymorphism.
FAU - Misdaq, Misbah
AU  - Misdaq M
AD  - Department of Clinical Chemistry, University Medical Centre Goettingen, 
      Goettingen, Germany.
FAU - Andag, Reiner
AU  - Andag R
FAU - Oellerich, Michael
AU  - Oellerich M
FAU - Asif, Abdul R
AU  - Asif AR
FAU - von Ahsen, Nicolas
AU  - von Ahsen N
LA  - eng
PT  - Journal Article
PL  - United States
TA  - Ther Drug Monit
JT  - Therapeutic drug monitoring
JID - 7909660
RN  - 0 (Guanine Nucleotides)
RN  - 0 (Thionucleotides)
RN  - 15867-02-4 (6-thioguanylic acid)
RN  - E7WED276I5 (Mercaptopurine)
RN  - EC 2.1.1.- (Methyltransferases)
RN  - EC 2.1.1.67 (thiopurine methyltransferase)
RN  - FTK8U1GZNX (Thioguanine)
RN  - Thiopurine S methyltranferase deficiency
SB  - IM
MH  - Apoptosis/drug effects/genetics
MH  - Cell Line, Tumor
MH  - Drug Hypersensitivity/*enzymology/*genetics
MH  - Gene Knockdown Techniques/methods
MH  - Guanine Nucleotides/genetics/metabolism
MH  - Humans
MH  - Immune Tolerance
MH  - Jurkat Cells
MH  - Mercaptopurine/metabolism/pharmacology
MH  - Methyltransferases/*deficiency/*genetics
MH  - Polymorphism, Genetic/drug effects
MH  - Purine-Pyrimidine Metabolism, Inborn Errors/*enzymology/*genetics
MH  - T-Lymphocytes/drug effects/*enzymology
MH  - Thioguanine/metabolism/pharmacology
MH  - Thionucleotides/genetics/metabolism
EDAT- 2012/09/14 06:00
MHDA- 2013/05/15 06:00
CRDT- 2012/09/14 06:00
PHST- 2012/09/14 06:00 [entrez]
PHST- 2012/09/14 06:00 [pubmed]
PHST- 2013/05/15 06:00 [medline]
AID - 00007691-201210000-00016 [pii]
AID - 10.1097/FTD.0b013e31826ec4b4 [doi]
PST - ppublish
SO  - Ther Drug Monit. 2012 Oct;34(5):584-92. doi: 10.1097/FTD.0b013e31826ec4b4.