title: Synergistic effects of nanosecond pulsed electric fields combined with low concentration of gemcitabine on human oral squamous cell carcinoma in vitro.
abstract: Treatment of cancer often involves uses of multiple therapeutic strategies with different mechanisms of action. In this study we investigated combinations of nanosecond pulsed electric fields (nsPEF) with low concentrations of gemcitabine on human oral cancer cells. Cells (Cal-27) were treated with pulse parameters (20 pulses, 100 ns in duration, intensities of 10, 30 and 60 kV/cm) and then cultured in medium with 0.01 µg/ml gemcitabine. Proliferation, apoptosis/necrosis, invasion and morphology of those cells were examined using MTT, flow cytometry, clonogenics, transwell migration and TEM assay. Results show that combination treatments of gemcitabine and nsPEFs exhibited significant synergistic activities versus individual treatments for inhibiting oral cancer cell proliferation and inducing apoptosis and necrosis. However, there was no apparent synergism for cell invasion. By this we demonstrated synergistic inhibition of Cal-27 cells in vitro by nsPEFs and gemcitabine. Synergistic behavior indicates that these two treatments have different sites of action and combination treatment allows reduced doses of gemcitabine and lower nsPEF conditions, which may provide better treatment for patients than either treatment alone while reducing systemic toxicities.
authors.affiliation: Department of Oral Medicine, School of Stomatology, Lanzhou University, Lanzhou Gansu, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Jinsong
authors.initials: J
authors.lastname: Guo
authors.forename: Shan
authors.initials: S
authors.lastname: Wu
authors.forename: Hongqing
authors.initials: H
authors.lastname: Feng
authors.forename: Shujun
authors.initials: S
authors.lastname: Sun
authors.forename: Jie
authors.initials: J
authors.lastname: Pan
authors.forename: Jue
authors.initials: J
authors.lastname: Zhang
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Beebe
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000473:pathology* / Q000628:therapy; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D004599:Electric Stimulation Therapy / Q000379:methods*; D006801:Humans; D009062:Mouth Neoplasms / Q000188:drug therapy / Q000473:pathology* / Q000628:therapy; D009336:Necrosis / Q000139:chemically induced; D009361:Neoplasm Invasiveness; D013997:Time Factors; D000093542:Gemcitabine
chemical_list: D000970:Antineoplastic Agents; D003841:Deoxycytidine; D000093542:Gemcitabine