Effects of heat shock and apoptosis induction on antitumor responses.
(A) 12B1-D1 cells (5 × 105) were incubated for 6 hours with 40 nM AP20187 or heat shocked for 1 hour at 42°C (HS), incubated with AP20187 for 6 hours, and then injected SC into BALB/c mice. Mice were followed for tumor development. Shown are pooled data from 3 experiments (n = 20 mice per group); P < .01 from day 13 onward. (B) 12B1-D1 cells were treated as in (A) and injected into SCID mice (n = 8 mice per group); P = not significant. (C) 12B1-D1 cells (2 × 104) were untreated or heat shocked for 1 hour at 42°C and immediately injected into BALB/c mice, 12B1-D1 + HS (A); or heat shocked for 1 hour at 42°C, incubated at 37°C for 6 hours, and then injected, 12B1-D1 + HS (B) (n = 8 mice per group); P = not significant. (D) Heat-stressed or nonstressed AP20187-treated 12B1-D1 cells (5 × 105) were frozen and thawed for 6 cycles to yield a necrotic lysate and coinjected with 2 × 104 live 12B1-D1 cells (n = 8 mice per group); P = not significant. Panels B, C, and D show representative data from a total of 6 experiments performed.
