Haloperidol induces demethylation and expression of the dual specificity phosphatase 6 gene in MIA PaCa-2 human pancreatic cancer cells.
OBJECTIVE
The effects of antipsychotics on various gene expressions through change in DNA methylation have been reported. Dual-specificity phosphatase 6 (DUSP6) is an extracellular signal regulated kinase 1/2 (ERK1/2)-selective phosphatase, and its expression can be suppressed by intronic methylation. Antipsychotic agent haloperidol affects ERK1/2 activity and could induce changes in DNA methylation as well as histone acetylation. In this study, we examined the effects of haloperidol on DUSP6 expression related to DNA methylation changes.


METHODS
The effects of haloperidol and 5-azacytidine, a demethylating agent, on expression and methylation of DUSP6 were quantitatively measured in MIA PaCa-2 human pancreatic carcinoma cells, in which DUSP6 expression is suppressed due to intronic hypermethylation. The growth rate of MIA PaCa-2 cells was also examined after treatment with haloperidol or 5-azacytidine.


RESULTS
Haloperidol increased DUSP6 expression in a concentration-dependent manner and inhibited MIA PaCa-2 cell proliferation; effects were comparable to those of 5-azacytidine. However, haloperidol did not induce DUSP6 expression in PANC-1 cells, another pancreatic cancer cell line without transcriptional suppression of DUSP6. Pyrosequencing methylation analysis confirmed the intronic hypermethylation of DUSP6 in MIA PaCa-2 and revealed that haloperidol and 5-azcytidine induced demethylation of CpG sequences in this region.


CONCLUSIONS
Haloperidol induced DUSP6 expression related to intronic demethylation and inhibited MIA PaCa-2 cell proliferation, which suggests demethylating activity and anti-cancer effects of haloperidol. These findings suggest the possible involvement of epigenetic regulatory mechanisms in the action mechanism of haloperidol.
Institute of Human Behavioral Medicine, Medical Research Center, Seoul National University, Seoul, Republic of Korea.
Se Hyun
SH
Kim
Hee Young
HY
Lee
Heesun
H
Yi
Yong Min
YM
Ahn
Yong Sik
YS
Kim
D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001374:Azacitidine / Q000494:pharmacology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D018899:CpG Islands / Q000235:genetics; D019175:DNA Methylation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D054642:Dual Specificity Phosphatase 6 / Q000235:genetics*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D044127:Epigenesis, Genetic; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006220:Haloperidol / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D007438:Introns; D008969:Molecular Sequence Data; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000473:pathology
D014150:Antipsychotic Agents; D004791:Enzyme Inhibitors; C517035:DUSP6 protein, human; D054642:Dual Specificity Phosphatase 6; D006220:Haloperidol; D001374:Azacitidine