Objective   To observe the effect of targeted therapy with

131

I-labeled affinity fusion polypeptide VEGF receptor 3 on human ovarian cancer transplanted into nude

mice.    Methods  

131

I-labeled polypeptide and anti-VEGFR-3 MAb were synthesized with Indogen method

cultured in vitro with LEC cells respectively

and their inhibitory effect on growth of LEC cells was detected by MTT. Human ovarian cancer cells were subcutaneously inoculated into 44 nude mice. Two weeks after tumor formation

20 mice were divided into polypeptide group (4.4  g per mouse)，

131

I-polypeptide group (7.4 MBq per mouse)，

131

I-anti-VEGFR-3 MAb (7.4 MBq per mouse)，and control group (0.2 ml saline)

5 mice in each group. The size of tumor was measured once a week for 4 weeks. Single photon emission computed tomography（SPECT）was performed when the tumor diameter reached 1cm in the other 24 mice.    Results   The in vitro inhibition rates of

131

I -polypeptide and

131

I-anti-VEGFR-3 MAb reached their peak in 72 and 96 h after treatment respectively (P0.05). The in vivo tumor volume in the 4 groups was (723±164)

(291±68)

(457±88)

and (792±112)mm

3

respectively，4 weeks after treatment

with a difference in

131

I-polypeptide，

131

I -anti-VEGFR-3 MAb and control groups (P0.05) but no difference in polypeptide group and control group. The average volume of the tumor was significantly smaller in the

131

I -polypeptide and

131

I -VEGFR-3 MAb than in the control group(P0.05).The growth of implanted tumor was inhibited by 63% and 44%

respectively.    Conclusion  

131

I-labeled high affinity fusion polypeptide can significantly inhibit the growth of human ovarian cancer transplanted into mice.