c-Jun N-terminal kinase is required for thermotherapy-induced apoptosis in human gastric cancer cells

Figure 1 Cell cycle change in SGC-7901 cells following thermotherapy for various time periods. A-C: Cell cycle distribution in SGC-7901 cells following thermotherapy for 0 h, 1 h, 2 h respectively. Thermotherapy increased the number of SGC-790l cells in G0/G1 phase, but reduced the number in S phase (P < 0.05) at 1 h and 2 h, compared with that at 0 h.

Figure 2 Apoptotic rate of SGC7901 cells with or without SP600125 treatment following thermotherapy for various time periods. A1, B1, C1, D1, E1: Apoptotic rate of SGC-7901 cells without SP600125 treatment, significantly increased after thermotherapy for 0.5, 1, 2 and 3 h, compared to that at 0 h (P < 0.01); A2, B2, C2, D2, E2: Apoptotic rate of SGC-7901 cells with SP600125 treatment, significantly inhibited cellular apoptosis induced by thermotherapy at 0.5, 1, 2 and 3 h (P < 0.01), compared to that at the same time points in the control groups. PI: Propidium iodine; FITC: Fluoresceine isothiocyanate.

Figure 3 Apoptosis of SGC-7901 cells with or without SP600125 treatment following thermotherapy for various time periods (×400). Apoptotic cells showing yellow fluorescence. A1, B1, C1, D1, E1: Apoptosis of SGC-7901 cells without SP600125 treatment, significantly increased after thermotherapy for 0.5, 1, 2 and 3 h, compared to that at 0 h (P < 0.01); A2, B2, C2, D2, E2: Apoptosis with SP600125 treatment, significantly inhibited cellular apoptosis induced by thermotherapy at 0.5, 1, 2 and 3 h (P < 0.01), compared to that at the same time points in the control groups.

Figure 4 Expression of p-c-Jun N-terminal kinase, Bax, caspase-3 and Bcl-2 proteins in SGC-7901 cells with or without SP600125 treatment following thermotherapy for various time periods. A1, B2, C1, D1: Expression of p-JNK, Bax, caspase-3 and Bcl-2 proteins in SGC-7901 cells without SP600125 treatment; A2, B2, C2, D2: Expression of p-JNK, Bax, caspase-3 and Bcl-2 proteins in SGC-7901 cells with SP600125 treatment; A3, B3, C3, D3: Comparison of p-JNK, Bax, caspase-3 and Bcl-2 proteins in SGC-7901 cells with or without SP600125 treatment; Expression of p-JNK, Bax, caspase-3 proteins in SGC-7901 cells with SP600125 treatment was significantly inhibited compared with that in SGC-7901 cells without SP600125 treatment (^bP < 0.01); Bcl-2 protein did not show an obvious change in SGC-7901 cells with or without SP600125 treatment (P > 0.05). JNK: c-Jun N-terminal kinase.

Figure 5 Expression of c-Jun N-terminal kinase at the mRNA level in SGC-7901 cells with or without SP600125 treatment following thermotherapy for various time periods. A: Expression of c-Jun N-terminal kinase (JNK) at the mRNA level in SGC-7901 cells without SP600125 treatment; B: Expression of JNK at the mRNA level in SGC-7901 cells with SP600125 treatment; C: Comparison of JNK at the mRNA level in SGC-7901 cells with or without SP600125 treatment; Expression of JNK at the mRNA level in SGC-7901 cells with SP600125 treatment was significantly inhibited compared with that in SGC7-901 cells without SP600125 treatment (^bP < 0.01).