Keywords:
RECEPTOR
;
CANCER
;
CANCER CELLS
;
CELLS
;
EXPRESSION
;
GROWTH
;
GROWTH-FACTOR
;
CELL
;
Germany
;
TISSUE
;
LINES
;
TIME
;
FAMILY
;
INDUCTION
;
TISSUES
;
CONTRAST
;
CELL-LINES
;
DOWN-REGULATION
;
MEMBER
;
MEMBERS
;
PHOSPHORYLATION
;
BREAST-CANCER
;
antibodies
;
antibody
;
immunohistochemistry
;
ASSAY
;
CARCINOMA CELLS
;
CELL-LINE
;
LINE
;
CANCER-CELLS
;
BETA
;
RT-PCR
;
adenocarcinoma
;
p21
;
CELL-SURFACE
;
RECEPTORS
;
DIFFERENTIAL EXPRESSION
;
cell lines
;
pancreatic cancer
;
CELL-GROWTH
;
signaling
;
PANCREATIC-CANCER
;
FAMILIES
;
DUCTAL ADENOCARCINOMA
;
independent growth
;
ENHANCED EXPRESSION
;
TGF-beta 1
;
HEPARAN-SULFATE PROTEOGLYCANS
;
LEVEL
;
pancreatic
;
ASSAYS
;
SULFATE
;
downregulation
;
lymph node
;
LYMPH-NODE
;
correlation
;
VIEW
;
DECREASED SURVIVAL
;
activin
;
bone morphogenic protein
;
CONTROLS CELLULAR-RESPONSES
;
glypican
;
heparan sulfate proteoglycans
;
SMAD PROTEINS
Abstract:
Glypican 1 (GPC1) is a cell surface heparan sulfate proteoglycan that acts as a co-receptor for heparin-binding growth factors as well as for members of the TGF-beta family. GPC1 plays a role in pancreatic cancer by regulating growth factor responsiveness. In view of the importance of members of the TGF-beta family in pancreatic cancer, in the present study, the role of GPC1 in TGF-beta, BMP and activin signaling was analyzed. Quantitative RT-PCR and immunohistochemistry were utilized to analyze GPC1 and TGF-beta, BMP and activin receptor expression levels. Panc-1 and T3M4 pancreatic cancer cells were transfected in a stable manner with a GPC1 antisense expression construct. Anchorage-dependent and -independent growth was determined by MTT and soft agar assays. TGF-beta 1, activin-A and BMP-2 responsiveness was determined by MTT assays and immunoblotting with p21, p-Smad1, and p-Smad2 antibodies. QRT-PCR demonstrated increased GPC1 mRNA levels in pancreatic ductal adenocarcinoma (PDAC) compared to normal pancreatic tissues (NPT), as described previously. There was a significant correlation between GPC1 mRNA levels and T beta RII, act-R1a, act-R1b, act-R2a, BMP-R1a, and BMP-R2 mRNA expression in NPT. In contrast, GPC1 mRNA expression correlated directly with act-R1a and BMP-R1a in NO PDAC cases and with act-R2a and BMP-R1a in lymph node positive cases. Down-regulation of GPC1 resulted in increased doubling time in Panc-1 but not in T3M4 cells, and decreased anchorage-independent growth in both cell lines. GPC1 down-regulation resulted in a slightly altered response towards TGF-beta 1, activin-A and BMP-2 in terms of growth, p21 induction and Smad2 phosphorylation. In conclusion, enhanced GPC1 expression correlates with BMP and activin receptors in pancreatic cancer. GPC1 down-regulation suppresses pancreatic cancer cell growth and slightly modifies signaling of members of the TGF-beta family of growth factors
Type of Publication:
Journal article published
Deep Link:
http://www.dkfz.de/cgi-bin/sel?http://www.dkfz.de/PublicationManager/Show/ShowJournal.aspx%3fpublishedId=3346
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