Relationships between local and systemic expression of interleukin-12 and plasma levels of vascular endothelial growth factor in patients with gastric cancer.
BACKGROUND
Interleukin 12 (IL-12) is a heterodimeric cytokine that exhibits potent anti-tumor and anti-metastatic activities. Very few studies have investigated the expression of IL-12 in patients with gastric cancer. The purpose of the present study was to evaluate the immunohistochemical expression and serum levels of IL-12, and plasma levels of vascular endothelial growth factor (VEGF) in patients with gastric cancer.


METHODS
IL-12 was immunohistochemically stained using monoclonal anti-human IL-12 antibody (1-1A4) in surgical specimens of 27 gastric cancer patients. IL-12-positive cells were counted and positive cell density was calculated. Blood was obtained before surgery. Serum levels of IL-12 and plasma levels of VEGF were assessed using the quantitative sandwich enzyme immunoassay technique. The relationships of IL-12-positive cell density, serum levels of IL-12, plasma levels of vascular endothelial growth factor (VEGF) and clinicopathological factors were evaluated.


RESULTS
Although IL-12-positive cell density was not associated with serum levels of IL-12, the IL-12-positive cell density tended to increase in patients with serum levels of IL-12 higher than the mean level (p=0.0518). IL-12-positive cell density significantly decreased in the patients with CEA positive or differentiated type. Moreover, IL-12-positive cell density tended to be inversely correlated with plasma levels of VEGF (p=0.0801, r=-0.343).


CONCLUSIONS
These results suggest that the immune efficiency in patients with gastric cancer may be reflected by IL-12-positive cell density and serum levels of IL-12. Thus, patients with low IL-12-positive cell density or serum levels of IL-12 in gastric cancer may require additional immunochemotherapy after surgery.
Nakayama
Yoshifumi
Y
Department of Surgery 1, University of Occupational and Environmental Health, Kita-Kyushu 807-8555, Japan.
Inoue
Yuzuru
Y
Nagashima
Nobuo
N
Katsuki
Takefumi
T
Matsumoto
Kentarou
K
Shibao
Kazunori
K
Tsurudome
Keisuke
K
Hirata
Keiji
K
Sako
Tatsuhiko
T
Nagata
Naoki
N
Itoh
Hideaki
H
D000368:Aged; D000369:Aged, 80 and over; D002452:Cell Count; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D018664:Interleukin-12 / Q000097:blood / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D013274:Stomach Neoplasms / Q000097:blood / Q000378:metabolism* / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000097:blood*
C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D018664:Interleukin-12