[Effect of irradiation on matrix metalloproteinases, vascular endothelial growth factor and microvessel density of mice bearing Lewis lung cancer].
OBJECTIVE
To investigate the effect of irradiation on matrix metalloproteinases (MMPs), vascular endothelial growth factor (VEGF) and microvessel density (MVD), which influence on tumor growth and metastases of mice bearing Lewis lung cancer (LLC).


METHODS
C57BL/6 mice bearing LLC were randomized into two groups to receive radiation and no-radiation, respectively. When tumor reached about 190 mm3 in volume on the fourteenth day after inoculation, the radiation group was irradiated to the primary tumor (6MV-X, 5 Gy/day, d14, 16, 18, 20). On the eighth day after irradiation, animals were killed to examine primary tumors, normal tissue near tumors. MMP-2, MMP-9, VEGF and MVD were checked by immunohistochemical means.


RESULTS
Immunohistochemical examination demonstrated an increased expression of MMP2, MMP9, VEGF and MVD in the tumor tissue of the radiation group (P<0.05). Additionally, the expression levels of MMP2 and MMP9 in the tumor tissue were higher than those in the normal tissue near tumor (P<0.05).


CONCLUSIONS
This study showed that irradiation might increased MMP2, MMP9, VEGF and MVD expression in the tumor tissue of mice bearing Lewis lung cancer. Our finding supports a potential way to overcome tumor metastasis induced by radiation if MMP inhibitor and anti-vascularization are combined to irradiation clinically.
Ai
Ping
P
Department of Head and Neck and Breast, Cancer Therapy Centre, West China Hospital, Sichuan University, Chengdu 610041, China.
Ren
Zhi-Gang
ZG
Wang
Xin
X
Wang
Shi-Chao
SC
Li
Ping
P
D000818:Animals; D018827:Carcinoma, Lewis Lung / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000528:radiation effects; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D051379:Mice; D008810:Mice, Inbred C57BL; D009368:Neoplasm Transplantation; D009389:Neovascularization, Pathologic / Q000473:pathology* / Q000532:radiotherapy; D014407:Tumor Cells, Cultured; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects
D042461:Vascular Endothelial Growth Factor A; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9