[Expression and clinical significance of IGF-II mRNA and bcl-2 protein in colorectal adenocarcinomas].
OBJECTIVE
Insulin-like growth factor II (IGF-II) can stimulate cell proliferation; B cell lymphoma 2 (bcl-2) protein can strongly inhabit cell apoptosis. Recently, the overexpression of IGF-II and bcl-2 in colorectal cancer has been found, but the combined detection of them has not been reported. The objective of this study was to investigate the relationship between the expression of IGF-II, bcl-2 and the invasion, metastases of colorectal adenocarcinomas and to analyze the clinical significance of combined detection of these factors.


METHODS
Forty-eight paraffin embedded samples from colorectal adenocarcinomas were selected. IGF-II mRNA was detected by using in situ hybridization. The expression of bcl-2 and PCNA protein were determined immunohistochemically, and TUNEL technique was used to detect apoptosis. Ten normal colorectal tissues were used as controls. The positive cell ratio of cancers was calculated by computer. The specimens with positive cell ratio < or = 30% were defined as negative.


RESULTS
The expressions of IGF-II mRNA and bcl-2 protein were significantly higher in colorectal adenocarcinomas (38.70% +/- 7.80% and 30.97% +/- 7.40%) than in normal colorectal tissues(23.12% +/- 4.07% and 12.69% +/- 1.31%) (P < 0.01) and were related to Dukes' stage and lymph node metastases but were not associated with patient's age, gender, tumor site, tumor size and tumor differentiation. A negative correlation was observed between IGF-II mRNA and bcl-2 protein (P < 0.05). A positive correlation between IGF-II mRNA and PCNA, apoptosis as well as a negative correlation between bcl-2 and apoptosis were observed (P < 0.01). There was no correlation between bcl-2 and PCNA (P > 0.05). The patients with IGF-II mRNA (+) and bcl-2 (-) were regarded as the worst prognosis.


CONCLUSIONS
The overexpression of IGF-II and bcl-2 in colorectal adenocarcinomas play an important role in the pathogenesis, progression, invasion, and metastases of the tumor. Determination of both IGF-II and bcl-2 expression would be helpful for decision making of adjuvant therapy.
Zhang
Ming-sheng
MS
Department of Oncology, Zhongnan Hospital of Wuhan University, Wuhan 430071, P. R. China. zms75@163.com
Yuan
Hong-yin
HY
Xiong
Bin
B
Deng
Qin
Q
Tang
Zhi-jiao
ZJ
Xia
Dong
D
D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D000328:Adult; D000368:Aged; D017209:Apoptosis; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000096:biosynthesis* / Q000235:genetics; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D018809:Proliferating Cell Nuclear Antigen / Q000096:biosynthesis / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D012004:Rectal Neoplasms / Q000378:metabolism* / Q000473:pathology
D018809:Proliferating Cell Nuclear Antigen; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D007335:Insulin-Like Growth Factor II