[Expression and significance of leukemia inhibitory factor in human pancreatic cancer].
OBJECTIVE
To explore the expression of leukemia inhibitory factor (LIF) and its clinicopathological significance in human pancreatic ductal adenocarcinoma (PDAC) and examine its regulatory role of biological behaviors of pancreatic cancer cells.


METHODS
The expression of LIF protein in 53 paired paraffin-embedded PDAC specimens and adjacent non-cancerous pancreatic tissues were detected by immunohistochemistry. The relationship between their expressions and clinicopathological characteristics was analyzed.Western bolt was used to examine the expression of LIF level in 14 paired fresh PDAC specimens and adjacent non-cancerous pancreatic tissues.Furthermore, Western blot and polymerase chain reaction (PCR) were used to detect the LIF-R mRNA and protein level of LIF in 6 pancreatic cancer cell lines (AsPC-1, BxPC-3, PANC-1, SW-1990, Capan-2 and Miapaca-2). And the assays of MTT, invasion and migration were used to detect the effects of LIF in regulating cell proliferation, invasion and migration in pancreatic cancer cell lines.


RESULTS
The expression of LIF increased in 53 cases of PDAC versus paired normal tissues (66.0% vs 35.8%; t = 3.031, P = 0.004). And its positive association with tumor TNM stage (χ² = 3.635, P = 0.057) and invasion depth (χ² = 3.726, P = 0.054) had no statistical significance.Univariate analysis revealed that LIF may be a correlative adverse prognostic indicator for patients with PDAC (χ² = 3.233, P = 0.072). The expression of LIF was much higher in 14 cases of PDAC than that in adjacent normal pancreatic tissues (t = 5.283, P < 0.01). The protein level of LIF was lower in Capan-2 cells than that in other 5 pancreatic cancer cell lines while mRNA level of LIF receptor was higher than that in other 5 cell lines. Also LIF could promote the proliferation, migration and invasion of Capan-2 cell (P < 0.05).


CONCLUSIONS
An over-expression of LIF may contribute to the development and progression of PDAC.LIF can promote the proliferation, migration and invasion in some pancreatic cancer cells.
Department of General Surgery, First Hospital of China Medical University, Shenyang 110001, China.
Fei
F
Peng
Department of General Surgery, First Hospital of China Medical University, Shenyang 110001, China. Email: zjphama@163.com.
Jianping
J
Zhou
Department of General Surgery, First Hospital of China Medical University, Shenyang 110001, China.
Weiwei
W
Sheng
Department of General Surgery, First Hospital of China Medical University, Shenyang 110001, China.
Danhua
D
Zhang
Department of General Surgery, First Hospital of China Medical University, Shenyang 110001, China.
Ming
M
Dong
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D021441:Carcinoma, Pancreatic Ductal / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D053605:Leukemia Inhibitory Factor / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000473:pathology
C507837:LIF protein, human; D053605:Leukemia Inhibitory Factor