Study On The Effect Of Arsenic Trioxide Combined With Gemcitabine On Mice T-cell Lymphoma In Vitro And In Vivo

Objective:It was detected by arsenic trioxide(ATO) and gemcitabine(GEM) monotherapy orcombination therapy for murine T cell lymphoma line EL-4cell proliferation in vitroinhibition by MTT assay.Construction of C57BL/6mice T-cell lymphoma subcutaneoustransplantation tumor animal models,arsenic trioxide and gemcitabine monotherapy orcombination therapy inhibit the mice lymphoma model on growth effects and discuss thepossible mechanism of action for the treatment of T-cell lymphoma model experimentalbasis and scientific evidence.Methods:(1) Determined by MTT method is used respectively to detect the ATO and GEMmonotherapy or combination of mouse T cell lymphoma cell line EL-4cell line proliferation;(2) The establishment of C57BL/6mice T-cell lymphoma xenograft models,were randomlydivided into the ATO monotherapy group,the GEM monotherapy group and the ATO andGEM combination group.Monotherapy groups were chosen the high-dose and the low doseof both drugs concentration,and set physiological saline as a negative control group,andkilled in the eighth and15th days.The survival status of each group was observed duringadministration and measuring body weight of mice.After the mice were sacrificed,weighedtumor tissue and calculate the inhibitory rate.Stripped tumor tissue,lymph nodes,liver andspleen,and made of pathological slices.Tumor tissue of CD3immunohistochemical stainingto verify the tumor is T-cell lymphoma.Then HE staining, observed the pathologicalmorphology under the action of drugs and if there are pathological liver,spleen,lymph nodemetastasis,and detect cell apoptosis by TUNEL method to tumor tissue.Result：(1) Effects of ATO and GEM monotherapy or combination therapy on EL-4cells: ATO monotherapy in2.5μmol/L~40μmol/L concentration range,with the increase of drug concentration,cell proliferation inhibition was significantly enhanced.When ATOconcentration higher than20μmol/L,the inhibition of cell was gradually increased withtime. GEM monotherapy in0.78125ug/L~50ug/L concentration range,inhibition of cellproliferation was enhanced with the drug concentration increased.In addition,in GEM1.5625ug/L~50ug/L concentration range,the inhibitory effect was enhanced gradually withthe prolonged duration of drugs action on cells. ATO and GEM combination therapyshowed,the inhibition rate in the same concentration of ATO and same action time,the GEM1.5625ug/L combined group was more significantly enhanced than the GEM0.78125ug/Lcombined treatment group.In addition,the inhibition rate was gradually increased with theextension of time.The inhibition rate of combination groups were higher than the ATO andGEM monotherapy groups.④The effect of ATO combined GEM was calculated by theformula in cell experiments is synergistic.(2)Drug ATO and GEM monotherapy orcombination therapy for mice T-cell lymphoma in vivo: Construction of EL-4cells intumor-burdened C57BL/6mice xenograft model.Tumor tissues CD3immunohistochemicalstaining showed diffuse membrane CD3strong positive reaction to verify tumor T-celllymphoma.The rate of tumorigenicity was100%. The strongest inhibition effectexperimental group is ATO and GEM combination group which executed on8th days,theinhibition rate was49.65%,better than ATO low-dose group and GEM low dose group whichexecuted on8th days.Additionally,the inhibition rate of the experimental group which miceexecuted on8th days higher than the15th days.The effect of ATO combined GEM wascalculated by the formula in in vivo experiments is additive effects. Tumor tissue, lymphnodes, liver, spleen HE staining showed that all the experimental groups present upperextremity lymph node metastasis in mice, but there are some differences about lower limblymph node metastasis,transfer rate of executed by15th day is significantly higher than8thday.④The apoptosis index of ATO high dose group were executed by8th day is highest andthe saline control group is lowest.Apoptosis index from high to low in turn is ATO high dosegroup, the ATO low-dose group, the GEM high dose group, the GEM low dose group,andtheATO/GEM combination group. Conclusion:(1)Within a certain range of concentrations,arsenic trioxide and gemcitabinemonotherapy inhibite EL-4cell proliferation.(2)Under experimental conditions,EL-4cellproliferation were significantly inhibited by arsenic trioxide combination withgemcitabine,and its cell inhibition rate is higher than the two drugs with single drug at thesame concentration,and combination therapy have a synergistic effect in cellexperiments.(3)Arsenic trioxide and gemcitabine monotherapy can inhibit T-cell lymphomain C57BL/6mice subcutaneously transplanted tumor growth,and the tumor suppressioneffect by gemcitabine is better than that of arsenic trioxide.(4)Under the experimentalconditions,arsenic trioxide combined with gemcitabine can inhibit T-cell lymphoma inC57BL/6mice subcutaneous transplantation tumor growth,the joint inhibitory rate higherthan the two drugs with single drug at the same concentration,and the combination therapyhas additive effect in vivo experiments.(5)Arsenic trioxide can promote apoptosis of Tlymphoma cells by the tumor-bearing mice.