Nicotine Synergizes with High-Fat Diet to Induce an Anti-Inflammatory Microenvironment to Promote Breast Tumor Growth

Figure 1

Coexposure to NIC plus HFD contributes to larger xenograft growth when compared to NIC or HFD alone. AA TN breast cancer cells HCC70 and HCC1806 (2×10⁶) were implanted subcutaneously in nude mice prefed (two weeks) HFD (rodent diet with 60 kcal % fat) and/or NIC (intraperitoneal injection twice/day, 0.75 mg/kg/mice/injection). The xenografts were allowed to grow for 8 weeks in the mice continued on HFD, NIC, or NIC plus HFD, after which the mice were euthanized and tumors excised. (a) Representative HCC70 tumors from control saline, NIC, or HFD alone or in combination (NIC+HFD) at 8 weeks (). (b) Weekly analysis of HCC70 tumor volume in various treatment groups. (c) Representative HCC1806 tumors from control saline, NIC, or HFD alone or in combination (NIC+HFD) at 8 weeks (). (d) Weekly analysis of HCC1806 tumor volume in various treatment groups. (e) Quantitative gene expression analysis of Aldh1, Sox2, Cd68, and Cd163 in HCC70 xenografts from various treatment groups, using human- (left panel) and mouse- (right panel) specific primer sets. (f) Quantitative gene expression analysis of Aldh1, Sox2, Cd68, and Cd163 in HCC1806 xenografts from various treatment groups, using human- (left panel) and mouse- (right panel) specific primer sets. (g) Western blot analysis of xenografts for various macrophage and mammary cancer stem cell markers. andcompared to saline orandcompared to the NIC group alone ().

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