The Effects Of Dexamethasone On The Growth And Apoptosis In The Naked Mouse Cervical Cancer

PART ONETHE EFFECTS OF DEXAMETHASONE ON THE GROWTH IN THE NAKED MOUSE CERVICAL CANCERObjectives:To investigate the effects of dexamethasone injected at different times and different doses on the growth of cervical cancer induced by Hela cells in naked mouse model. Materials and methods:Hela cells were inoculated subcutaneously into BALB / c mice. (1)The same doses of dexamethasone were injected into peritoneum from the sixth or the sixteenth day after tumor inoculation for 10 days continuously.(2)The different doses of dexamethasone were injected into peritoneum from the sixteenth day after tumor inoculation for 10 days continuously. Diameters of tumor were measured every two or three days.The volumes and the inhibit rates of tumor were calculated.Results:(1)Dexamethasone suppressed cervical cancer growths at different injection times. The tumor sizes in different groups treated by dexamethasone at different time were significantly smaller than these in the control group(P<0.01).(2)There was difference in tumor volume between different time injection (P <0.01). The inhibition rate of tumor in early injection was higher(94.36%). The inhibition rate of tumor in late injection was lower(53.57%).(3) The tumor sizes in different groups treated by different doses of dexamethasone were significantly smaller than this in the control group(P<0.001). The inhibition rates of tumor is 53.57%～73.99% .(4) In vivo, different doses had different influence on the tumor. 1)When doses of dexamethasone were less than 62.5 mg?kg–1?d–1, the effects increased with the doses accordingly. The volumes of tumor reduced gradually. There were obviously different in each group (P<0.01). 2)62.5 mg?kg–1?d–1～125 mg?kg–1?d–1 had the best result, At that dose, the volumes of tumor was the smallest (0.38 cm3±0.04 cm3～0.40 cm3±0.01 cm3,the control group is 1.47 cm3±0.03 cm3), 3)When doses were more than 125 mg?kg–1?d–1, with the doses increased, the effects of treatment were depressed, the volumes of tumors were increased (P<0.001), but they were smaller in size than the control group(P<0.001).Conclusions:(1)Dexamethasone injected at different times and different doses can repress cervical tumor growth.(2)The effects of dexamethasone injected at different times on tumor growth are different, and these effects have some time-dependence .(3) These effects of dexamethasone injected in different doses on tumor growth are concerned with its doses. PART TWOTHE EFFECTS OF DEXAMETHASONE ON THE APOPTOSIS IN THE NAKED MOUSE CERVICAL CANCERObjectives:To investigate the effects of dexamethasone injected at different times and different doses on the cell apoptotic of cervical cancer induced by Hela cells in naked mouse model. Materials and methods:After PART ONE, the tissues of tumor were obtained, and apoptotic bodies were observed by transmission electron microscopy and counted by TUNEL.Results:(1)Dexamethasone injected at different times and different doses induced tumor cell apoptosis compared with control group (P<0.001);.(2)There was difference in tumor apoptotic bodies between different time injection (P <0.01). In early injection, there was obvious apoptotic body under EM and the number of apoptotic body was much more by TUNEL inspection than those of group injected lately.(3) In vivo, dexamethasone in different doses significantly induced tumor apoptosis compared with control group (P<0.001);but different doses had different influence on the tumor:1)When doses of dexamethasone were less than 62.5 mg?kg–1?d–1, the effects increased with the doses accordingly. The apoptotic bodies increased gradually. They were obviously different in each group (P<0.01).2)62.5 mg?kg–1?d–1～125 mg?kg–1?d–1 had the best result. The apoptotic bodies are clearest under EM and number of TUNEL under LM is biggest(413±87.26～400±100.71,the control group is 160±101.35).3)When doses were more than 125 mg?kg–1?d–1, with the doses increased, the effects of treatment were depressed, the apoptotic bodies also reduced (P<0.001), but the number of TUNEL bodies were larger than the control group(P<0.001).Conclusions:(1)Dexamethasone injected at different times and in different doses can induce tumor cell apoptosis in vivo.(2)The effects of dexamethasone injected at different times are difference. These effects have some time-.dependence(3)In vivo, the effects of dexamethasone on tumor cell apoptosis are concerned with its doses.