[Expression of Snail and E-cadherin in pancreatic carcinoma and clinical significance thereof].
OBJECTIVE
To investigate the expression of Snail, a newly discovered inhibitory transcription factor, and E-cadherin in pancreatic carcinoma (PC) and clinical significance thereof.


METHODS
Immunohistochemistry was used to examine the expression of Snail and E-cadherin in 56 specimens of PC obtained during operation. PC cells of the line of Panc-1 and transfected with pCMV-Tag2B-Snail, a eucaryotic expression vector coding Snail, so as to obtain a stable clone named Panc-1-Snail. RT-PCR was used to detect the mRNA expression of Snail gene in the Panc-1-Snail cells. Immunofluorescence technique and Western blotting were used to detect the expression of E-cadherin in the Pan-1-Snail cells. Transwell cell culture chamber method was used to examine the invasion ability of the Panc-1-and Panc-1-Snail cells.


RESULTS
Twenty of the 56 PC specimens (36%) were positive in Snail, mainly located in the nuclei. Seventeen of the 20 Snail-positive PC specimens were with and 3 without lymph node metastasis (P = 0.006); and 7 of the 8 PC specimens with lymph node metastasis were Snail-positive and only 1 was Snail-negative (P = 0.001). Twenty-six PC specimens showed low expression of E-cadherin with remarkable heterogeneity. Of the 20 Snail-positive PC specimens 13 showed low expression of E-cadherin and only 7 showed normal expression of E-cadherin; and 13 of the 36 Snail-negative PC specimens showed low expression of E-cadherin (P = 0.038). RT-PCR showed strong Snail mRNA expression in the Pan-1 cells. Both Western blotting and immunofluorescence technique showed the depression of E-cadherin expression. The Transwell chamber test showed that the number of penetrating Pan-1-Snail cells after 24-hour incubation was (174 +/- 8)/200X field of view, significantly greater than that of the Pan-1 cells [(96 +/- 4)/200X field of view, P < 0.01].


CONCLUSIONS
Re-expressed in PC and accelerating the invasion of PC through depressing E-cadherin expression, Snail may present a new marker for predicting the aggressiveness of PC.
Yin
Tao
T
Centre of Pancreas Surgery, Union Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan 430022, China.
Wang
Chun-you
CY
Liu
Tao
T
Zhao
Gang
G
Zha
Yun-hong
YH
D015153:Blotting, Western; D015820:Cadherins / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D005455:Fluorescent Antibody Technique; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014162:Transfection
D015820:Cadherins; D012333:RNA, Messenger; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors