Effects of bafilomycin A1, a vacuolar type H⁺ ATPase inhibitor, on the thermosensitivity of a human pancreatic cancer cell line

Figures & data

Figure 1. The pHi of AsPC-1 cells incubated with bafilomycin A1 and/or EIPA at 37°C, 60 min. Shows the pHi in pHe 6.8 medium. Each data point is the mean ± 1 SE from 10 measurement. The pHi in the combination of the two drugs and in the pHe 6.8 medium was lower than any other experimental value and it was statistically significant (C; control, EI; 10 µM EIPA, BA; 1 µM bafilomycin A1, BA+ EI; 1 µM bafilomycin A1+ 10 µM EIPA).

Figure 2. Effect of bafilomycin A1 and/or EIPA on the thermosensitivity of AsPC-1 cells at pHe 7.4. (a) The bafilomycin A1 and/or EIPA effect at 37°C and (b) the drug effect after heating at 44°C. The data shown are mean from 15 measurements. The viability with/without the drugs or the heating in pHe 7.4 medium did not differ significantly from the control (C; control, EI; 10 µM EIPA, BA; 1 µM bafilomycin A1, BA+ EI; 1 µM bafilomycin A1+ 10 µM EIPA).

Figure 3. Effect of bafilomycin A1 and/or EIPA on the thermosensitivity of AsPC-1 cells at pHe 6.8. (a) The bafilomycin A1 and/or EIPA effect after incubation at 37°C and (b) the drug effect after heating at 44°C. The data shown are mean from 15 measurements. The viability of heated cells in the combination of the two drugs was lower than any other viability (p < 0.05) (C; control, EI; 10 µM EIPA, BA; 1 µM bafilomycin A1, BA+ EI; 1 µM bafilomycin A1+ 10 µM EIPA).

Figure 4. Effect of bafilomycin A1 and/or EIPA on the growth of AsPC-1 tumours. (a) The mean tumour volume of the non-heated group and (b) the mean tumour volume of the heated group. The mean value of eight tumours/groups are shown. Only heating after an injection of both bafilomycin A1 and EIPA ± 1 SE inhibited the tumour growth significantly, compared with controls (p = 0.0071) (C; control, EI; 3.0 mg kg⁻¹ EIPA, BA; 1.0 mg kg⁻¹ bafilomycin A1, BA+ EI; 1.0 mg kg⁻¹ bafilomycin A1+ 3.0 mg kg⁻¹ EIPA).