Over-expressed and truncated midkines promote proliferation of BGC823 cells in vitro and tumor growth in vivo.
OBJECTIVE
To determine whether midkine (MK) and its truncated form (tMK) contribute to gastric tumorigenesis using in vitro and in vivo models.


METHODS
Human MK and tMK plasmids were constructed and expressed in BGC823 (a gastric adenocarcinoma cell line) to investigate the effect of over-expressed MK or tMK on cell growth and turmorigenesis in nude mice.


RESULTS
The growth of MK-transfected or tMK-transfected cells was significantly increased compared with that of the control cells, and tMK-transfected cells grew more rapidly than MK-transfected cells. The number of colony formation of the cells transfected with MK or tMK gene was larger than the control cells. In nude mice injected with MK-transfected or tMK-transfected cells, visible tumor was observed earlier and the tumor tissues were larger in size and weight than in control animals that were injected with cells without the transfection of either genes.


CONCLUSIONS
Over-expressed MK or tMK can promote human gastric cancer cell growth in vitro and in vivo, and tMK has greater effect than MK. tMK may be a more promising gene therapeutic target compared with MK for treatment of malignant tumors.
Wang
Qing-Ling
QL
Immunology and Reproductive Biology Lab, Medical School and State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, Jiangsu Province, China.
Wang
Hui
H
Zhao
Shu-Li
SL
Huang
Ya-Hong
YH
Hou
Ya-Yi
YY
D000818:Animals; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D000078792:Midkine; D013274:Stomach Neoplasms / Q000378:metabolism / Q000473:pathology*
D016207:Cytokines; D000078792:Midkine