兔肝VX_2瘤射频消融后不同区带PCNA mRNA和VEGF表达

Effect of radiofrequency ablation on PCNA mRNA and VEGF expression in rabbit liver VX_2 tumor models

目的研究兔肝VX2瘤射频消融(RFA)后不同区带增殖细胞核抗原(PCNA)mRNA和血管内皮生长因子(VEGF)表达,观察其对凋亡和增殖的影响。方法将48只实验兔制成VX2肝移植肿瘤模型,分成RFA组(42只)及对照组(6只),分别于RFA后即刻、1 d、2 d、1周、2周、3周后处死,对肝移植肿瘤组织通过HE染色、Annexin V-FITC/PI标记、PCNA mRNA及VEGF检测来观察不同时期不同区带的肿瘤细胞凋亡及增殖。结果对照组VX2肿瘤呈浸润性生长。RFA组术后中央消融区呈大片坏死,边界区见炎性反应细胞及残留癌细胞;RFA组术后中央消融区内即刻出现大量坏死细胞,以针道区为主,坏死百分率约(45.16±4.44)%;3周后针道区坏死率仍明显高于热凝固区及边界区(F=142.089,P=0.000),此时,各区带内肿瘤细胞凋亡率均明显下降,接近术前水平;针道区在1 d后PCNA mRNA一直维持低表达水平;热凝固区在3周后PCNA mRNA表达恢复到术前对照水平(P=0.159);边界区的PCNA mRNA表达在2周时较1周时明显升高(P=0.000),但仍低于术前对照组(P=0.001),3周后边界区PCNA mRNA的表达则高于术前对照组(P=0.031);RFA后边界区VEGF表达水平明显高于针道区及热凝固区(P<0.05)。结论 RFA对针道细胞可以达到完全杀灭,但对于边界区的残留,RFA可能促进其复发及转移,仍需要进一步治疗。

Objective To study the expression of proliferating cell nuclear antigen （PCNA） mRNA and vascular endothelial growth factor （VEGF） of different zones after radiofrequency ablation （RFA） was performed on rabbit liver VX2 tumor models, in order to observe RFA＇s effect on cells＇ apoptosis and proliferation. Methods The tumor models were divided into two groups. One was radiofrequency ablation （RFA） group, which consisted of 42 rabbits liver VX2 tumor models. The other was the control group, which consisted of 6 rabbits liver VX2 tumor mod- els. All the models were observed immediately, 1 d, 2 d, 1 w, 2 w, 3 w separately after RFA. By HE staining, Annexin V-FITC/PI mark, PCNA mRNA and VEGF tests, we observed the apoptosis and proliferation of the cells in different periods and different zones after RFA. Results In the control group, tumor showed infiltrative growth. In the RFA group, after RFA, large areas of necrosis were found in the central ablation zone, while inflammatory cells and residual tumor cells were found in the boundary zone. After RFA, a large number of necrotic cells were found in the target areas immediately, especially in the needle tract zone, and the necrosis rate was about （45.16 ± 4.44） % ; necrosis rate in the needle tract zone 3 weeks after RFA was still significantly higher than thermal co- agulation zone and the boundary zone （ F = 142. 089, P = 0. 000）. Simultaneously, 3 week after RFA, apoptosis rate of tumor cells in every zone was significantly decreased, approaching pre-RFA levels; the PCNA mRNA ex- pression level of needle tract zone remained low 1 d after RFA, and the PCNA mRNA expression level of thermal coagulation zone 3 weeks after RFA returned to the level of pre-RFA （ P = 0. 159）, and PCNA mRNA expression level of the boundary zone 2 week after RFA was significantly higher compared to that 1 week after RFA （ P = 0. 000）. But still lower than the control group pre-RFA （P =0. 001）. But 3 weeks after RFA, PCNA mRNA ex- pression level was higher than the control group pre-RFA in the boundary zone （P =0. 031 ） ; VEGF expression of boundary zone of RFA group was significantly higher than the needle tract zone and thermal coagulation zone （P 〈 0.05）. Conclusion Cells in needle tract zone after RFA can be completely killed, but for the residual of border zone, RFA may contribute to the recurrence and metastasis, which still need further treatment.