Expression of regenerating gene I in gastric adenocarcinomas: correlation with tumor differentiation status and patient survival.
BACKGROUND
Regenerating gene I (REG) was identified as a growth factor for pancreatic islet beta cells. Enhanced REG expression was observed during the healing of gastric mucosa. REG expression was observed in various tumors including gastric carcinoma, but to the authors' knowledge, the correlation between REG expression and clinicopathologic characteristics and patient prognosis have not been evaluated.


METHODS
The REG messenger RNA level was analyzed by Northern blot analysis and localization was performed by in situ hybridization and immunohistochemistry in gastric adenocarcinoma specimens. The correlations between REG expression and clinicopathologic features and survival of the patients were analyzed.


RESULTS
Of the 68 patients studied, 24 (35%) were positive for REG. There was a significant consistency in the intensity and localization of REG transcript and protein expressions. REG expression was enhanced in advanced T classification tumors and in tumors that were not well differentiated. A significant number of metastatic lymph nodes were present in REG-positive tumors. Overall and disease-free survival were found to be poor for patients with REG-positive tumors. REG expression was reported to be an independent predictor of overall patient survival.


CONCLUSIONS
Determination of REG expression may help to identify aggressive gastric tumors and to tailor appropriate therapy for patients with REG-positive tumors.
Dhar
Dipok Kumar
DK
Second Department of Surgery, Shimane Medical University, Izumo, Japan. nigeka33@shimane-med.ac.jp
Udagawa
Jun
J
Ishihara
Shunji
S
Otani
Hiroki
H
Kinoshita
Yoshikazu
Y
Takasawa
Shin
S
Okamoto
Hiroshi
H
Kubota
Hirofumi
H
Fujii
Toshiyuki
T
Tachibana
Mitsuo
M
Nagasue
Naofumi
N
D000230:Adenocarcinoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology*; D000328:Adult; D000368:Aged; D015152:Blotting, Northern; D002135:Calcium-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051847:Lithostathine; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009419:Nerve Tissue Proteins; D011379:Prognosis; D012333:RNA, Messenger / Q000032:analysis; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology*
D002135:Calcium-Binding Proteins; D051847:Lithostathine; D009419:Nerve Tissue Proteins; C497617:REG1A protein, human; D012333:RNA, Messenger