| Electrical impulse chemotherapy (EIC) is a regional physical approach in the treatment of neoplasm, the mechanism is that reversible electroporation on the reginal cell membrane is aroused in vitro by the use of electric pulse (EP), which selectly improves the passage of chemical medication into cells, to kill the tumor cells. Recently, good effect has been obtained in the I,II clinic trials. However no report regarding the therapeutic mechanism of the malignant tumor by only using EP has been published. In this study, the tumor models in vivo and vitro were treated by energy-controllable steep pulse(ECSP), to disscuss the effectivity,possibility and security of ECSP in treatment of malignant tumor. The main results are as follows:1,To investigate the influence of the energy controllable steep pulses (ECSPs) on the biological activities of human ovarian carcinoma cell in vitro. After action by different intensities of steep pulses, the acute and delayed effects on human ovarian carcinoma cell line SKOV3 were investigated by measuring the cell growth curves and 3-(4,5-dimethylthiazol-z-yl)- 2,5 -dipheny tertrazolium blue (MTT) colorimetric assay. Cell cycle was detected by flow cytometry (FCM), morphological changes were observed by inverted light and electron microscope. The results were: ⑴ MTT assay demonstrated that there was an accordant dose-response relationship with the action of steep pulses on SKOV3 cells, the kill probability was increased along with dose which indicated that the acute injury of tumor cells was induced by the highest dose; ⑵ The cell growth curve showed that the cell proliferation ability was distinctly inhibited along with the increase of dose; ⑶ Analysis of cell cycle by FCM indicated that cells in periodof S and G2/M decreased, and in G0/G1 increased, which presenting a dose-dependent trend; ⑷ The morphological dynamic changes of SKOV3 cell in the pulse fields were observed by micrography, which showed that tumor cells moved to anode and might have negative charges; ⑸ By observation with electron microscope, irreversible electrical breakdown (IREB) of cell was seemed to be caused by steep pulses , leading to dissolving necrosis. ⑹ The chemical character of cultrural liquid could be changed by the steep pulse filed. With the change of PH value between the two platinum electrodes (Pt electrodes) needles by electrolysis of steep pulse filed, the survival circumstances of tumor cells were altered. These results indicate that ECSP not only can kill the human ovarian carcinoma cell by acute and delayed injuring, but also can change the normal living circumstances of the cells by the effects of electrolysis which resulting in death of cells finally. 2, To investigate the killed effects of ECSP and the survival status for U14 cervical cancer in mice. 40 female BALB/C mice were inoculated with the solution of U14 cervical cancer cells line. Then, the histomorphological changes, suppressive curves and the survival effects were examined and compared between experimental and control group. The results were: ⑴ the histological and antitumor assay studies showed that steep pulses electrical field could injury tumor cells and inhibit cell proliferation ability. After treatment, pyknosis, karyoclasis and karyolysis of tumor cells were observed by light and electron mircroscope. Serious changes appeared more time later. ⑵ the tumor volumes were measured and the responses to treatment were evaluated 31 days after the treatment between these two groups. In 20 mice of experimental group, complete responses (CR) were 9(45%), progressive diseases (PD) were 11(55%), in which 4 died (mortality was 20%); but in control group, all 20 mice were PD(100%), in which 9 died (mortality was 45%). There was a significant difference in the constitution of these two groups(P﹤0.01). ⑶ The survival period of experimental group and control group was averagely 52.05 days and 33.05 days. There was a significant difference in survival curve(P﹤0.01). These results indicated that energy con...
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