News Finding: Gambhir's team appears to have found a way to force any of numerous tumor types to produce a biomarker whose presence in the blood of mice unambiguously signifies cancer, because none of the rodents' tissues -- cancerous or otherwise -- would normally be making it.
Paper Finding: (B) ROC analysis revealed a significant ability of the tumor-activatable MC system to differentiate tumor-bearing from healthy subjects by measuring and computing plasma SEAP AUC.
News Context: Or a tumor -- especially a small one -- simply may not secrete enough of the trademark substance to be detectable. Gambhir's team appears to have found a way to force any of numerous tumor types to produce a biomarker whose presence in the blood of mice unambiguously signifies cancer, because none of the rodents' tissues -- cancerous or otherwise -- would normally be making it. The particular promoter Gambhir and his colleagues snapped into the minicircle ahead of the SEAP gene normally regulates a gene called survivin that, in adults, is only "on" in cancer cells.
Paper Context: (A) AUC analysis of plasma SEAP measurements over 2 wk revealed significant differences between tumor-bearing mice receiving MCs (n = 7) and healthy mice receiving either MCs (n = 7) or 5% glucose (n = 5) (*P < 0.05; **P < 0.01). (B) ROC analysis revealed a significant ability of the tumor-activatable MC system to differentiate tumor-bearing from healthy subjects by measuring and computing plasma SEAP AUC. Across six mice a significant (P < 0.05) positive correlation was noted between these two measures, showing the ability of this tool to assess tumor burden provided that the tumor is in one location.