[Expression and significance of DARPP-32 in gastric carcinoma].
OBJECTIVE
To investigate the significance of DARPP-32 protein expression in gastric carcinoma tissue and cell lines.


METHODS
The expression of DARPP-32 protein in normal gastric mucosa and gastric carcinoma tissue was evaluated by immunohistochemical staining using streptavidin-biotin complex technique. The expression in gastric carcinoma tissue and cell lines was evaluated by Western blotting.


RESULTS
The expression rate of DARPP-32 protein in gastric adenocarcinoma tissue (92.7%) was significantly higher than that in normal gastric mucosa (52.6%, P < 0.05). There was no significant association between DARPP-32 protein expression and degree of tumor differentiation, local invasion and distant metastasis. As compared with adjacent non-carcinomatous gastric mucosa, both DARPP-32 and its truncated isoform t-DARPP were overexpressed in gastric adenocarcinoma tissue (t = 2.45, P = 0.015); and t-DARPP overexpression was more frequently seen. Expression of DARPP-32 and t-DARPP could also be detected in human gastric cancer cell lines. The expression of DARPP-32 protein was obviously reduced in SGC7901 drug-resistant cell strains.


CONCLUSIONS
DARPP-32 is overexpressed in gastric carcinoma. It may play an important role in gastric carcinogenesis. The underlying signal pathways in neoplastic gastric epithelium may also be related to the multi-drug resistance property of gastric cancer cells.
Wang
Jin
J
Institute of Digestive Disease, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
Pan
Yang-lin
YL
Liu
Na
N
Guo
Chang-cun
CC
Hong
Liu
L
Fan
Dai-ming
DM
D000230:Adenocarcinoma / Q000378:metabolism*; D000368:Aged; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D045744:Cell Line, Tumor; D051937:Dopamine and cAMP-Regulated Phosphoprotein 32; D004317:Doxorubicin / Q000494:pharmacology; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000378:metabolism*; D014750:Vincristine / Q000494:pharmacology
D000903:Antibiotics, Antineoplastic; D000972:Antineoplastic Agents, Phytogenic; D051937:Dopamine and cAMP-Regulated Phosphoprotein 32; D009419:Nerve Tissue Proteins; D010750:Phosphoproteins; D014750:Vincristine; D004317:Doxorubicin