Tumour growth and resistance to gemcitabine of pancreatic cancer cells are decreased by AP-2alpha overexpression.
BACKGROUND
Activator protein-2alpha (AP-2alpha) is a transcription factor that belongs to the family of AP-2 proteins that have essential roles in tumorigenesis. Indeed, AP-2alpha is considered as a tumour-suppressor gene in different tissues such as colonic, prostatic or breast epithelial cells. Moreover, AP-2alpha also participates in the control of colon and breast cancer cells sensitivity towards chemotherapeutic drugs. Despite its potential interest, very few data are available regarding the roles of AP-2alpha in pancreatic cancer.


METHODS
We have developed a stable pancreatic CAPAN-1 cell line overexpressing AP-2alpha. Consequences of overexpression were studied in terms of in vivo cell growth, gene expression, migration capacity and chemosensitivity.


RESULTS
In vivo tumour growth of CAPAN-1 cells overexpressing AP-2alpha was significantly decreased by comparison to control cells. An altered expression pattern of cell cycle-controlling factors (CDK-4, CDK-6, cyclin-G1, p27(kip1) and p57(kip2)) was observed in AP-2alpha-overexpressing clones by microarrays and western blot analysis. Promoter activity and ChIP analysis indicated that AP-2alpha induces p27(kip1) protein levels by direct binding to and transactivation of its promoter. Moreover, AP-2alpha overexpression increased the chemosensitivity of CAPAN-1 cells to low doses of gemcitabine and reduced their in vitro migration capacity.


CONCLUSIONS
Our data suggested that AP-2alpha overexpression could be exploited to decrease in vivo tumour growth of pancreatic cancer cells and to increase their sensitivity to gemcitabine.
Jonckheere
N
N
INSERM, U837, Université de Lille 2, Centre de Recherche Jean-Pierre Aubert, Place de Verdun, 59045 Lille cedex, France.
Fauquette
V
V
Stechly
L
L
Saint-Laurent
N
N
Aubert
S
S
Susini
C
C
Huet
G
G
Porchet
N
N
Van Seuningen
I
I
Pigny
P
P
D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D015153:Blotting, Western; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation / Q000187:drug effects; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D015870:Gene Expression; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D018613:Microscopy, Confocal; D020411:Oligonucleotide Array Sequence Analysis; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000378:metabolism; D050656:Transcription Factor AP-2 / Q000235:genetics* / Q000378:metabolism; D014162:Transfection; D023041:Xenograft Model Antitumor Assays; D000093542:Gemcitabine
D000964:Antimetabolites, Antineoplastic; D050656:Transcription Factor AP-2; D003841:Deoxycytidine; D000093542:Gemcitabine