Safety Assessment Of B Ladder Cancer Specific Oncolytic Adenovirus

Objective: Surgery,Radiotherapy and Chemotherapy are still given priority for the treatment of bladder cancer. In addition, adjuvant chemotherapy to improve the effect of tumor treatment is also recommended. However, the recurrence of bladder cancer is still very high. New bladder cancer specific oncolytic adenovirus has become a hot study for bladder cancer biological treatment. It can duplicate specially in bladder cancer cell and kill them. This meas targeted therapy for cancer make a big improvement. Now, the curative effect of oncolytic adenovirus has been demonstrated, but its toxicity and safety have still been controversial. Several studies reported oncolytic adenovirus toxicity, but most focused on the acute toxicity and long-term toxicity experiment. But no one reported the adenovirus reproductive toxicity research. So this studies will test the bladder cancer specially oncolyt ic adenovirus(Ad-PSCAE- UPII-E1A- AR) genneral reproductive toxicity and teratogenic toxicity exper iments. we will evaluate whether AdPSCAE-UPII-E1A- AR could disturb fetal rats bone structure and observe the first filialgeneration development in body weight and visceral tissue. This study would provided meaning data for the safety of oncolytic adenovirus.Methods: we entrusted Beijing Five Jiahe Company amplified, purif ied and identified our lab constructing bladder cancer specific oncolytic adenovirus(Ad-PSCAE- UPII-E1A- AR). The mice were obtained from Gansu Collegen of trational Chinese Medicine Animal Center. This study can devided into three parts: acute toxicity experiment, genneral reproductive toxicity experiment, teratogenic toxicity experiment. The method of acute toxicity experiment is that oncolytic adenovirus was injected abdominal cavity of the mice by one time and observing the changes of mice behavior and weight during 14 days. we collect the peripheral blood of mice in anesthesia to test blood cells and blood biochemistry. Then, the mice was euthanized and anatomy. The tissue organ were taken out and performed the pathological slice and heamatoxylin and eosin staining. We observed whether oncolytic adenovirus could cause the change of organ tissue in microscopic. In general reproductive toxicity experment, male mice were first administration. They are injected oncolytic adenovirus for 28 days by intramuscular injection on the other day. After the 14 days, female mice began to be adminisstrated for 14 days by intramuscular injection on the other day. Then,male and female mice were in one cage. The pregnant mice divided into two parts. One part was euthansia after 16 days, and taken out the fetal rats, removing the internal argans and skin, performing skeletal stain and observing the bone change. The other was natural childbirth. the first filial generationg(F1) are feeding for 30 days,and evaluate the variat ion of body weight. when the mice were was euthanized, the organ were performed pathological slices, observing the changes of tissue in microscope. In the teratogenic toxicity experiment, the pregnant mice was administrated at sixth day. Then they devide into two groups. One was euthanized at sixteenth day, took out the fetal rats, Then, observing the changes of embryonic bone structure. the other was natural childbirth. F1 are feeding and natural growth for 30 days, assessing the variation in the growth progress and development. After the mice were killed, the organ tissue were performed pathological slices and HE stain, the observing the changes in microscope.Result: In the experiment of acute toxicity,the experimental mice show the twist behavior, which means abdominal pain. There was a significant difference between two group in body weight. During the progress of automy, abdominal cavity appear severe ascires.the liver present a serious tissue necrosis and normal lobulate were broken. However, other organ had not shown serious change. In general reproductive toxicity study, comparing control group with low dose group,middle dose group,high dose group, there was no signif icant difference in fetal rats nest weigh and placental weight. Body length and tail length of fetal rats show no statistical difference. The fetal mice skeletal stain ing was also normal. During the development process of the filial generation, there was satistic al difference in weight comparing with control group, but the curve of body weight changes show that this difference is not obvious. This may be due to individual difference and discepancy of the pregnant mice. In the process of teratogenic toxicity test, comparing with control group, there was no significant difference in the placenta and weight of fetal rats. During the development process of F1, the changes of mice weight show statistical signif icance. Howerer, in the progress of growth curve, this difference is not very obvious, so this maybe due to the different time of pregnant and the weight of female. Depend on the curve of growth, we do not think this variation was cause by oncolytic adenovirus.Conclusion: In actue toxicity, the bladder cancer specific oncolytic andenovirus( AdPSCAE-UPII-E1A- AR) may cause severe liver toxicity. So the liver may be the adenovirus target organ. In addition, after about 100 fold of treatment dose adminstration, no mice was dead, So the safety of oncolytic adenovirus is worth confirming. In general reproductive toxicity test and teratogenic toxicity experim ents, there was no sinif icant difference in nest weigh,placental weight, Body length, tail length, and F1 development between several groups. So, our constructed oncolytic adenovirus has no obvious effects on reproductive system in mice. It is a relat ively safe bioloical biological agents for tumor gene therapy. So, this oncolytic adenivirus has litt le effect for pregnant and medical staff in fertility and teratogenicity.