Synuclein gamma predicts poor clinical outcome in colon cancer with normal levels of carcinoembryonic antigen.
BACKGROUND
Synuclein gamma (SNCG), initially identified as a breast cancer specific gene, is aberrantly expressed in many different malignant tumors but rarely expressed in matched nonneoplastic adjacent tissues. In this study, we investigated the prognostic potential of SNCG in colon cancer particularly in the patients with normal carcinoembryonic antigen (CEA) levels.


METHODS
SNCG levels were assessed immunohistochemically in cancer tissues from 229 colon adenocarcinoma patients with a mean follow-up of 44 months. Correlations between SNCG levels and clinicopathologic features, preoperative serum CEA level, and clinical outcome were analyzed statistically using SPSS.


RESULTS
SNCG levels in colon adenocarcinoma were closely associated with intravascular embolus and tumor recurrence but independent of preoperative serum CEA levels. SNCG expression was an independent prognostic factor of a shorter disease-free survival (DFS) and overall survival (OS) (P < 0.0001). Multivariate analysis revealed that both tissue SNCG and serum CEA were independent prognostic factors of DFS (P = 0.001, <0.0001, respectively) for 170 patients with colon adenocarcinomas. Importantly, SNCG remained a prognostic determinant of DFS and OS (P = 0.001, 0.002) for 97 patients with normal preoperative serum CEA level.


CONCLUSIONS
Our results suggest for the first time that SNCG is a new independent predicator for poor prognosis in patients with colon adenocarcinoma, including those with normal CEA levels. Combination of CEA with SNCG improves prognostic evaluation for patients with colon adenocarcinoma.
Liu
Caiyun
C
Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University School of Oncology, 52 Fucheng Road, Haidian District, Beijing 100142, China.
Dong
Bin
B
Lu
Aiping
A
Qu
Like
L
Xing
Xiaofang
X
Meng
Lin
L
Wu
Jian
J
Eric Shi
Y
Y
Shou
Chengchao
C
D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002272:Carcinoembryonic Antigen / Q000378:metabolism*; D003106:Colon / Q000378:metabolism / Q000473:pathology; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000378:metabolism*; D009364:Neoplasm Recurrence, Local / Q000378:metabolism* / Q000473:pathology; D009367:Neoplasm Staging; D011379:Prognosis; D015996:Survival Rate; D055815:Young Adult; D051845:gamma-Synuclein / Q000378:metabolism*
D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D009363:Neoplasm Proteins; C104249:SNCG protein, human; D051845:gamma-Synuclein