| Traditional therapy for cancer including surgical operation, chemotherapy and radiotherapy. These treatments were used single or combinally. But the recurrent rate and modality rate are more higher, and the patients suffer from the severe side effects caused by the therapy. Targeted toxins represent a new approach to specific therapy. Being a new type of anti-tumor reagent, chimeric toxin have specific cytotoxin on some kinds of carcinoma cells, without cytotoxin on normal cell. With the rapid progress in biotechnology , biotechnological drug therapy has became the forth treatment after surgical operation , Chemotherapy and Radiotherapy. LHRH-PE40 are a kind of chimeric toxin constructed by fusing PE40 with LHRH.There are more LHRH receptors on the membrane of some kinds of carcinoma cells than normal tissue,so chimeric toxin were targeted to the carcinoma by LHRH and kill them without demage to normal tissue.The aim of the study is to observe the effect of LHRH-PE40 on the growth of cervical carcinoma and the binding capacity of LHRH-PE40 to different pathological cervical carcinoma. So the target of LHRH-PE40 can be identified .The effect of LHRH-PE40 were investigated to provide the foundation for clinical application in future. 1, At first, the effect of LHRH-PE40 injection on cervical carcinoma were observed by cultivation of cell in vitro.Cytotoxin analysis showed that LHRH-PE40 could inhibit the growth of Hela cell.The inhibiting effect depended on the time and dosage.Judging from the dose-response profile and time-response profile,the mix effective dosage of LHRH-PE40 is 0.625 μg/ml,the optimal treating time is 48～72h,The IC50 of LHRH is 0.969μg/ml.The effect of LHRH-PE40 on proliferation and apoptosis of Hela cell were observed.The results showed the percentage of Ki-67 positive cell and Bcl-2 positive cell were declined,and the ratio of apoptosis cell increased.It suggested that LHRH-PE40 inhibited the proliferation of carcinoma ,and promoted the apoptosis of carcinoma.The cell cycle change analysed by flow cytometer showed the same result.With the concentration 2.2 μg/ml, Only fragments of cell were represented under flow cytometer, although cells with normal apperance represented under light microscopic. With the concentration of 1.0 μg/ml,the ratio of G0/G1 phase cell increased while the percentage of S phase cell decreased.These result suggested that LHRH-PE40 inhibited the conversion of cell from S phase to G2/M phase.2, No LHRH-PE40 were found to bind to normal cervix connective tissue, Squamous epithelium,but LHRH-PE40 were found on endometrium and endothelium of fallopian tube and myometrium.It showed that there were LHRH receptor on these tissue.The expression of fluorescence on cervical carcinoma were 92%.Among weak positive and negative cases, well differentiated squamous cell carcinoma accounted for 75%,while middle and poor differentiated squamous cell carcinoma accounted for 25%,significant differences were found between them(P<0.05). Among middle positive cases, well differentiated squamous cell carcinoma accounted for 14% only, while middle and poor differentiated squamous cell carcinoma accounted for 86%,and significant differences also were found between them(P<0.05).All of the three strong positive cases were well differentiated adenocarcinoma.It suggested that well differentiated squamous cell carcinoma were not sensitive to LHRH-PE40, while middle and poor differentiated squamous cell carcinoma were much more sensitive.The most sensitive cases to LHRH were cervical adenocarcinoma.3, The cytotoxin became lesser and lesser with the ratio of LHRH and LHRH-PE40 increasing from 100:1,250:1,500:1 to 750:1. LHRH receptors on the surface of the carcinoma were satured when the ratio of LHRH and LHRH-PE40 attached to 500:1,the value of OD were stable even if more LHRH were added. The fluorescence became weak when LHRH competed the receptor with LHRH-PE40.It is suggested that LHRH-PE40 worked by binding to LHRH receptor on the membrane of carc...
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