Transcriptional control of tight junction proteins via a protein kinase C signal pathway in human telomerase reverse transcriptase-transfected human pancreatic duct epithelial cells.
In human pancreatic cancer, integral membrane proteins of tight junction claudins are abnormally regulated, making these proteins promising molecular diagnostic and therapeutic targets. However, the regulation of claudin-based tight junctions remains unknown not only in the pancreatic cancer cells but also in normal human pancreatic duct epithelial (HPDE) cells. To investigate the regulation of tight junction molecules including claudins in normal HPDE cells, we introduced the human telomerase reverse transcriptase (hTERT) gene into HPDE cells in primary culture. The hTERT-transfected HPDE (hTERT-HPDE) cells were positive for the pancreatic duct epithelial markers such as CK7, CK19, and carbonic anhydrase isozyme 2 and expressed epithelial tight junction molecules claudin-1, -4, -7 and, -18, occludin, JAM-A, ZO-1, ZO-2, and tricellulin. By treatment with fetal bovine serum or 12-O-tetradecanoylphorbol 13-acetate (TPA), the tight junction molecules were up-regulated at the transcriptional level via a protein kinase C (PKC) signal pathway. A PKC-alpha inhibitor, Gö6976, prevented up-regulation of claudin-4 by TPA. Furthermore, a PKC-delta inhibitor, rottlerin, prevented up-regulation of claudin-7, occludin, ZO-1, and ZO-2 by TPA. By GeneChip analysis, up-regulation of the transcription factor ELF3 was observed in both fetal bovine serum- and TPA-treated cells. Treatment with small interfering RNAs of ELF3 prevented up-regulation of claudin-7 by TPA. These data suggest that tight junctions of normal HPDE cells were at least in part regulated via a PKC signal pathway by transcriptional control.
Yamaguchi
Hiroshi
H
Department of Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
Kojima
Takashi
T
Ito
Tatsuya
T
Kimura
Yasutoshi
Y
Imamura
Masafumi
M
Son
Seiichi
S
Koizumi
Jun-ichi
J
Murata
Masaki
M
Nagayama
Minoru
M
Nobuoka
Takayuki
T
Tanaka
Satoshi
S
Hirata
Koichi
K
Sawada
Norimasa
N
D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D057167:Claudins / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology / Q000502:physiology*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D010183:Pancreatic Ducts / Q000166:cytology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D050783:Proto-Oncogene Proteins c-ets; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D019098:Telomerase / Q000235:genetics / Q000378:metabolism*; D019108:Tight Junctions / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
D057167:Claudins; D004268:DNA-Binding Proteins; C105529:ELF3 protein, human; D008565:Membrane Proteins; D011518:Proto-Oncogene Proteins; D050783:Proto-Oncogene Proteins c-ets; D034741:RNA, Small Interfering; D014157:Transcription Factors; D011493:Protein Kinase C; C509186:TERT protein, human; D019098:Telomerase