Fig. 7: Hyperinsulinemia drives Py230 tumor growth in obese OVX mice.

a Schematic showing design of insulin pump study in NC-fed OVX mice. Py230 cells are orthotopically injected at week 0 then insulin pumps delivering 0.2 U/day are implanted at week 3 and tumors followed to week 7. For the E0771 cells, insulin pumps delivering 0.2 U/day are implanted at day 0 then E0771 cells orthotopically injected on day 13 and tumors followed to day 35. Mice with saline pumps (Sal) are colored magenta and mice with insulin pumps (Ins) are labeled cyan. b Fasting plasma insulin at end of study (number of mice n = 6 for Sal, n = 7 for Ins; two-tailed t test). Mice with saline pumps are shown in magenta, mice with insulin pumps in cyan. c Fasting blood glucose measured weekly in mice on NC following insulin pump implantation (number of mice n = 7 for control, n = 5 for insulin; *p < 0.05, **p < 0.01 by two-way ANOVA with Bonferroni’s multiple comparisons test). d Mean Py230 tumor volume measured weekly with calipers after insulin pump implantation (number of mice n = 8 per group; **p < 0.01, ****p < 0.0001 by two-way ANOVA with Bonferroni’s multiple comparisons test). e Mean individual Py230 tumor weight at end of study (number of tumors n = 30 for Sal, n = 32 for Ins; two-tailed t test). f Mean E0771 tumor volume measured weekly after insulin pump implantation (number of mice n = 10 for saline, n = 8 for insulin; *p < 0.05, ****p < 0.0001 by two-way ANOVA with Bonferroni’s multiple comparisons test). g Mean individual E0771 tumor weight at end of study (number of tumors n = 27 for Sal, n = 24 for Ins; two-tailed t test). h Schematic showing design of insulin pump study in obese OVX mice on HFD. Py230 cells are orthotopically injected at week 0 then pumps delivering 0.6 U/day insulin (Ins, cyan) or saline (Sal, magenta) are implanted at week 3. i Schematic showing design of diazoxide study in obese OVX mice on HFD. Py230 cells are orthotopically injected at week 0, mice are switched to HFD (orange) or HFD + diazoxide diet (DZ, yellow) at week 3, then tumors are followed to week 7. j Fasting plasma insulin at end of study (number of mice n = 8 for Sal, n = 10 for Ins, n = 9 for HFD, n = 12 for DZ, one-way ANOVA with Tukey multiple comparison test). k Mean Py230 tumor volume measured weekly in insulin pump groups (number of mice n = 9 for Saline, n = 10 for Insulin; ****p < 0.0001 by two-way ANOVA with Bonferroni’s multiple comparisons test). l Individual Py230 tumor weight at the end of the pump study (number of tumors n = 36 for Sal, n = 40 for Ins; **p(0.0014) by two-tailed t test). m Mean Py230 tumor volume measured weekly in DZ mice group (number of mice n = 4 for HFD, n = 14 for DZ; **p < 0.01, ****p < 0.0001 by two-way ANOVA with Bonferroni’s multiple comparisons test). n Individual Py230 tumor weight at the end of the diazoxide study (number of tumors n = 16 for HFD, n = 55 for DZ; two-tailed t test). o Schematic of the TRF study with implanted insulin pumps in obese OVX mice. Arrowheads indicate implantation of pumps on weeks 11 and 15. Py230 cells injected at week 13. Mice on NC are shown in blue, mice on AL in orange, mice on TRF in green and mice on TRF with insulin pumps (TRF + I) in cyan. p Py230 individual tumor volume after 10 weeks (number of tumors n = 48 for NC, n = 52 for AL and TRF, n = 24 for TRF + I; ****p(0.0001) by one-way ANOVA with Tukey’s multiple comparisons test). Data presented as mean ± SEM. Asterisks show statistical significance as indicated.