RESUMO
Objective To investigate the influencing factors involved in the establishment of a C57BL/6 J model of metastatic melanoma in the lung,including the way of tumor inoculation,the number of inoculated cells and the time of tumor formation. Methods Mouse melanoma B16F10 cells were cultured in vitro. 1)Eighteen healthy male C57BL/6 J mice were randomly divided into three groups. Mice in each group received 100 μL cell suspension(including 3 ×106 melanoma cells)via intravenous,intraperitoneal and subcutaneous injection,respectively. After two weeks,the mice were killed and dissected,and the tumor growth and metastasis were observed. 2)Eighteen male mice were randomly divided into three groups. Mice in each group were injected with 3 ×106cells,1 ×106cells, and 3 ×105cells through the tail vein,respectively. After two weeks,mice were killed and dissected,and the tumor growth and metastasis were observed. 3)Eighteen male mice were randomly divided into three groups. Mice in each group were injected with 1×106cells though the tail vein. Mice were killed and dissected after one week, two weeks and three weeks, respectively. The growth and metastasis of tumor were observed. Results 1)The success rate of lung metastasis was 100% in the mice with intravenous injection,but not in mice receiving intraperitoneal injection and subcutaneous injection. 2)The size of metastatic melanoma nodules were moderate in mice inoculated by 1 ×106cells. The number of melanoma metastatic foci was too high in the mice inoculated with 3 ×106cells,but too low in the mice inoculated with 3 ×105cells. 3)Significant metastatic melanoma foci were observed in the mice killed and dissected after two weeks with no death. The number of melanoma foci in the lung was too high in the mice killed after three weeks,while was too low in the mice killed at one week after tumor cell inoculation. Conclusions Intravenous injection of 1×106mouse melanoma cells into C57BL/6 J mice and killed after two weeks is an optimal method for establishment of a mouse model of metastatic melanoma in the lung, and is worth of recommendation.
RESUMO
DNA polymerase iota (Polt),as well as Revl,Polκ and Polη,are all Y family DNA polymerases,which are able to replicate damaged DNA via translesion synthesis pathway.However,Pol(t) has the lowest fidelity among all DNA polymerases in both correct and inaccurate DNA templates.Also Pol(t) can bypass certain DNA damages and accumulate mutations.Recent studies show that the aberrant expression of Pol(t) is observed in human uveal melanoma,breast cancer,bladder cancer,lung cancer and esophageal cancer,which may contribute to the tumorigenesis and progression of tumor.The special role of Pol(t) in replicating damaged DNA may contribute to the resistance in oncotherapy.
RESUMO
Objective To investigate the effect of heme oxygenase-1 ( HO-1 ) on the acute radiation-induced skin injury by gene transfer.Methods Thirty-three male SD rats were randomly divided into three groups as PBS-injected group,Ad-EGFP-injeeted group and Ad-HO-1-injected group ( n =11 ).In each group,three rats were used for determining the expression of target gene and the other rats were irradiated on the buttock skin with 40 Gy electron beam generated by a linear accelerator.Immediately after irradiation,rats were administered with a subcutaneous injection of PBS,Ad-EGFP or Ad-HO-1,respectively.Subsequently,the skin reactions were measured twice a week using the semi-quantitative skin injury scale.Results The strong positive expression of HO-1 was observed in subcutaneous dermal tissue after injection of Ad-HO-1.Compared to the PBS-injected group or the Ad-EGFP-injected group,a significant mitigation of skin injury was observed in Ad-HO-1-injected mice 14 d after irradiation (q =0.000-0.030,P ＜ 0.05 ).Conclusions HO-1 could significantly mitigate radiation-induced acute skin injury and Ad-HO-1 could be used to treat radiation-induced skin injury.