Repeated electroporation enhances the responsiveness to cisplatin-based intra-tumoral chemotherapy in murine breast cancer: revival of the electro-chemotherapy concept

Background and aims: Electroporation demonstrated certain modulable actions on tumoral cell membrane permeability to increase the intracellular bioavailability of chemotherapeutic drugs. The current in vivo study aimed to investigate the synergic effect of concomitant electroporation application to the intratumoral administration of cisplatin on murine invasive ductal adenocarcinoma breast cancer. Methods: The fragments of the extracted tumor were implanted subcutaneously in healthy female Balb/C mice. Having reached the determined tumoral volume, the mice were randomly divided into five groups, including control, intratumoral cisplatin injection, tumoral electroporation application, electrochemotherapy (ECT), and double course ECT. The normalized tumoral volume and the inhibition ratios were calculated during a 30-day follow-up period. The data were tested by ANONA, and a statistically significant level was set at P<0.05. Results: The inhibition ratio was significantly different between the intra-tumoral cisplatin administration and tumoral electroporation application groups compared to the control group (P<0.05). ECT displayed superior results in comparison to the two later groups (P<0.05). The double-course ECT group even represented a significant difference compared to the ECT group (P<0.05). Conclusion: Concomitant ECT to the cisplatin intratumoral administration indicated contributive anti-tumoral impacts in an in vivo murine model of invasive ductal adenocarcinoma breast cancer. ECT promises further applications to overcome the occurrence of therapeutic resistance to chemotherapeutic drugs.