Ca(2+) is an important mediator of nanosecond steep pulse-induced apoptosis in human ovarian cancer SKOV3 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the role of Ca(2+) in nanosecond steep pulse (NSP)-induced apoptosis of human ovarian carcinoma cell line SKOV3 in vitro.</p><p><b>METHODS</b>The early apoptotic rate of SKOV3 cells treated with NSP was detected by Annexin V/PI double staining and flow cytometry. MTT assay was used to detect the viability of the cells pretreated with BAPTA-AM (0, 25, 50 and 100 µmol/L) chelation for 1 h to increase the intracellular free Ca(2+) prior to NSP exposure, and the cell morphological changes and caspase 12 expression were detected using Hoechst 33342 staining and Western blotting, respectively.</p><p><b>RESULTS</b>Flow cytometry showed that NSP induced early apoptosis of SKOV3 cells, and the optimal effect was achieved with the treatment parameter configuration of field strength of 90 kV/cm, pulse width of 100 ns, frequency of 1 Hz, and exposure time of 30 s. The highest early apoptotic rate and necrosis rate was (60.31∓5.67)% and (1.35∓0.39)%, respectively. Pretreatment with BAPTA-AM chelation prior to NSP exposure significantly increased the cell viability (P<0.05), and resulted also in lowered apoptosis rate and decreased expression of caspase 12 (P<0.05).</p><p><b>CONCLUSION</b>NSP can induce apoptosis in SKOV3 cells. Increased intracellular free Ca(2+) functions as an important mediator in NSP-induced cell apoptosis, which may also involve Ca(2+)-mediated endo- plasmic reticulum pathway.</p>

Pathological studies of tissue damage in experimental rabbit liver cancer induced by energy controllable steep pulses / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy of energy controllable steep pulses (ECSP) in the treatment of rabbit VX2 cancer implanted in livers.</p><p><b>METHODS</b>A tumor model was successfully established using 30 rabbits. ECSP were applied to liver cancer in half of these rabbits and the rest were used as controls. After exposure to ECSP, tissues were obtained and subjected by routine HE and transmission electron microscopic (TEM) observation. The survival time of the animals and the statuses of each group were recorded.</p><p><b>RESULTS</b>From pathological observations, ECSP showed effectively destructive action compared with that of the unexposed group. A clear borderline can be seen between necrotic cancer and its surrounding normal tissue. Irreversible cell changes were present under TEM. The survival periods of the experimental and control group were 83.1 days and 39.0 days respectively, and there was a significant difference between the two groups (Z = -2.943, P < 0.01).</p><p><b>CONCLUSION</b>ECSP can effectively treat rabbit VX2 cancer implanted in the liver; also it is safe for its surrounding normal tissues. ECSP can be a useful method for local treatment of liver cancer.</p>