The effect of Kanglaite Injection in combination with gefitinib on angiogenesis in mice with Lewis lung cancer

Objective: By observing the effect of Kanglaite (KLT) Injection in combination with gefitinib on angiogenesis in mice with Lewis lung cancer, to explore its possible mechanism. Methods: Lewis lung cancer model was established in C57BL/6 mice. Forty model mice were randomized into 4 groups: control group, KLT treatment group, gefitinib treatment group, and KLT+gefitinib treatment group. Using immunohistochemistry and RT-PCR technology to observe and compare tumor growth and angiogenesis in each treatment group. Results: The average weight of the tumor in KLT+gefitinib treatment group was lower than those in the KLT treatment group and the gefitinib treatment group; the difference was statistically significant (P < 0.01). Judging from the inhibition rate, KLT, gefitinib, and KLT+gefitinib can inhibit the growth of the transplanted tumor, especially for the combination treatment. The microvessel density (MVD)-positive labeling index (LI) in control group, KLT treatment group, gefitinib treatment group and the KLT+gefitinib treatment group were 24.35±1.06, 18.25±1.36, 20.09±1.46 and 14.46±0.98, respectively. The MVD of the KLT+gefitinib treatment group was lower than those of the two single drug groups; the difference was statistically significant (P < 0.01). The expression levels of VEGF and KDR proteins in the KLT treatment group and the gefitinib treatment group were lower than that of the control group (P <0.05) and higher than that of the KLT+gefitinib group (P < 0.05). The expression levels of VEGF and KDR mRNAs in the KLT+gefitinib group was lower than those of the two single drug groups; the difference was statistically significant (P < 0.05). Conclusion: KLT combined with gefitinib treatment may exert synergistic effect on anti-angiogenesis, so as to obtain synergistic anti-tumor effect. Copyright © 2013 by TUMOR.