Fig 1.
Temperature profile of the incubator during heat-up phase to 42°C steady-state hyperthermia.
Dots represent temperature read off the incubator display over three independent runs, and lines represent the temperature recorded by a sensor placed in the culture dish, immersed in medium during those same runs.
Fig 2.
Effect of thermoradiotherapy treatment on clonogenic cell survival of cancer cells.
Clonogenic cell survival curves of human (A, B) and canine (C-H) cancer cell lines. The corresponding LQ parameters along with their enhancement factors are given in a Table (I). Unpaired t-test. Mean of at least three independent experiments ±SEM is shown.
Fig 3.
Different conditions of hyperthermia pre-treatment affect radiation-sensitivity of A549 cells.
Effect of the time gap between hyperthermia and radiation on clonogenic cell survival (A). Influence of the hyperthermia temperature of 41, 42 and 43°C in combination with radiation on A549 clonogenic cell survival (B). Treatment with hyperthermia (42°C, 1 h) first versus radiation first affects clonogenic cell survival of A549 cells (C). One-way ANOVA with Dunnett’s multiple comparison test. Mean of at least three independent experiments ±SEM is shown.
Fig 4.
Analysis of DNA damage and apoptosis/necrosis in hyperthermia, radiation and combined thermoradiotherapy-treated A549 cells.
DNA damage (tail intensity analyzed by Comet assay) in A549 cells (A). Apoptosis (B) and necrosis (C) in A549 cells 48 h after treatment. Luminescent/fluorescent signal intensity values were normalized by the number of cells (coupled luminescence assay) in each well. Mixed model ANOVA with Tukey’s multiple comparison test. Mean of three independent experiments ±SEM is shown.
Fig 5.
Levels of HSP70 and Rad51 in control and thermoradiotherapy-treated human and canine cancer cell lines.
Cell lysates analyzed by immunoblotting for HSP70 and Rad51 and β-actin in control (-) and thermoradiotherapy (+; (42°C, heat-up plus 1 h) followed by ionizing radiation (6 Gy))-treated cells (A). Representative experiment of three experiments performed independently is shown. Quantification of HSP70 and Rad51 immunoblot signal normalized to β-actin (B). Mean of three independent experiments ±SEM is shown.
Fig 6.
HSP70 knockdown in A549 cells.
Efficiency of HSP70 downregulation 48 h after transfection in A549 cells; immunoblot (upper panel) and relative quantification of HSP70 normalized to β-actin (lower panel) and normalized to non-transfected cells, mean of three independent experiments ±SEM is shown (A). Effect of HSP70 knockdown on clonogenic cell survival of A549 cells treated with radiation or combined thermoradiotherapy (B). A control siRNA (siCtrl) was used versus HSP70-KD cells. The corresponding LQ parameters along with their enhancement factors are given in a table (lower panel). Unpaired t-test.