Cemazar M, Miklavcic D, Sersa G
Department of Tumor Biology, Institute of Oncology, Ljubljana, Slovenia.
Jpn J Cancer Res. 1998 Mar;89(3):328-33. doi: 10.1111/j.1349-7006.1998.tb00566.x.
Electrochemotherapy (ECT) involves the use of locally applied electric pulses to increase delivery of chemotherapeutic drugs into cells in tissues. ECT with bleomycin (BLM) is a very effective local treatment, but different tumors have different response rates to ECT. The aim of our study was to compare the responsiveness of SA-1 and EAT tumors to BLM and ECT in vitro and in vivo, in order to find possible reasons for the observed difference in response rate. The difference in sensitivity to ECT in vitro between the SA-1 and EAT cells was 10-fold and was the same as the difference in sensitivity to chronic BLM exposure, as measured by tetrazolium-based colorimetric (MTT) assay. This difference in sensitivity between SA-1 and EAT to ECT was also reflected in tumor cure rate. A six-times lower dose of BLM was needed to obtain local tumor control in SA-1 than in EAT tumors. Therefore, we suggest that the difference in sensitivity to BLM and ECT predominantly reflects the difference in intrinsic sensitivity of the cells to BLM.
电化学疗法（ECT）是指利用局部施加的电脉冲来增加化疗药物向组织细胞内的递送。博来霉素（BLM）联合ECT是一种非常有效的局部治疗方法，但不同肿瘤对ECT的反应率不同。我们研究的目的是比较SA-1和EAT肿瘤在体外和体内对BLM和ECT的反应性，以找出观察到的反应率差异的可能原因。通过基于四氮唑的比色法（MTT）测定，SA-1细胞和EAT细胞在体外对ECT的敏感性差异为10倍，与对慢性BLM暴露的敏感性差异相同。SA-1和EAT对ECT的这种敏感性差异也反映在肿瘤治愈率上。与EAT肿瘤相比，SA-1肿瘤获得局部肿瘤控制所需的BLM剂量低6倍。因此，我们认为对BLM和ECT的敏感性差异主要反映了细胞对BLM的内在敏感性差异。
