Study On The Effect Of Recombinant Human GM-CSF In Chemotherapy-induced Oral Mucosa Lesions And Its Mechanism

In order to overcome chemotherapy-induced severe oral lesions on malignant tumors,we established the mice model of oral mucosa lesions by methotrexate(MTX)． We observed the effect of recombinant human GM-CSF(rhGM-CSF)on oral mucosa lesions,and evaluated the effect of rhGM-CSF in the treatment of chemotherapy-induced oral ulcers in clinic trial,and explored the mechanism by which rhGM-CSF promotes the recovery of oral mucosa lesions in this model．MethodsAnimal experiments:According to the random principle,a total of 501mice were randomly divided into eight groups as following:①control,②low-dose MTX,③intermediate-dose MTX(IDMTX),④high-dose MTX,⑤IDMTX+GM0,⑥IDMTX+GM2,⑦MTX40+Calcium Folinat(cF)and⑧MTX40+CF+GM0．The physiological saline solution (0.5ml)was i．P．injected into mice in control group．Various doses of MTX(0．5ml)were i．p．injected into mice in other groups only once．RhGM-CSF(0．3ml,5gg／kg．d)was injected s．C．into the same mice at the same time as the administration of MTX in groups⑤and⑧,or CF(0．5ml,15mg／m2．d)was administrated i．P．12 hours later in the same mice in group⑦and⑧,or rhGM-CSF was administrated two days later in the same mice in group⑥．CF and rhGM-CSF were injected during five days(once per day)．During 10 consecutive days afteradministration of MTX,2 to 6 mice were killed in each day in all the groupsand the pathological changes of oral mucosa were observed under the opticalmicroscope． Clinical trial: A total of 79 inpatients were randomly divided into twogroups．RhGM-CSF pasting-slices were locally applied in oral ulcers in the treated group(three times per day)．RhGM-CSF-free pasting slices were locally applied in the control group instead．Routine observations were done before and after treatment． In vitro experiment:The cultured normal fibroblasts of fetal oral mucosa were researched in vitro．The effects of dif．ferent rhGM-CSF concentrations on proliferation and DNA synthesis of fibroblasts were observed by cell number measurement and the method Of 3H-TdR incorporation on 2nd,4th,6th days.Statistical analyses:The statistical analyses were performed using theSPMR software． Results1．The incidence(63．0％)and the integral rate(19.4～56％)of mice oral mucosa lesions in the group of IDMTX were significantly higher than that in other groups．The death rate(<5％)in group of IDMTX was lqwer than that in other groups．2．The incidence(30．53％and 30．99％)and the integral rate(19．47％and 17．25％)of mice oral mucosa lesions in groups of IDMTX+GM0 and IDMTX+GM2 were significantly lower than that in group IDMTX(55．56％and 36．31％)．The severe degree of ulcers in the former two groups was lighter than that in the latter．The difference of the former two groups and the latter was statistically significant(P<0．01)．The death rate(2．11％)of the group IDMTX+GM0 was the lowest among the three groups．The incidence(33．33％ and 36．11％) and the integral rate(25．69％and 26．39％)of mice oral mucosa lesions in groups of MTX40～GM0+CF and MTX40+CF were significantly lower than that in the group MTX40(63．04％ and 55．98％)．The severe degree of ulcers in the former two groups was lighter than that in the latter．The difference of the former two groups and the latter was statistically significant(P<0．01)． 3．After three days treatments,the total efficiency rate(89．7％)of thetreated group was significantly higher than that in control group(32．5％)．The difference of the two groups was statistically significant(P<0．001)． 4．The proliferation and DNA synthesis of fibroblasts of fetal oral mucosa was stimulated by different rhGM-CSF concentrations．The optimal concentration of rhGM-CSF was 80～100ng／ml at which the proliferation of the fibroblasts achieved the best state．When the concentration was higher than 100ng／ml,the stimulating effect decreased gradually． Conclusions 1．The higher lesion rate and lower death rate of mice oral...