Figure 7. Synergistic effect when cultured in hypoxia.

Two pancreatic cancer cell lines (AsPc1, MiaPaCa2) were cultured in either normoxic (21% O₂) or hypoxic (2% O₂) conditions with different drug combinations for 48 hr. (A) Cell viability was measured by MTT assays. Drugs tested were bortezomib (B1: 1.6 nM; B2: 16 nM; B3: 166 nM) and toyocamycin (T1: 25 nM; T2: 250 nM; T3: 2500 nM). (B) Combination index (CI) was calculated as described in Materials and Methods. CI <1 indicates synergism between two drugs. Fa: affected fraction. Data point 1: 1.6 nM bortezomib, 25 nM toyocamycin); Data point 2: 16 nM bortezomib, 250 nM toyocamycin.