Rate of (CO2)-C-14 production from variously labeled forms of [C-14]glucose in human breast invasive ductal carcinoma tissues

To establish possible cancerous aggressiveness between the metabolism of va riously labeled [C-14]glucose in the human breast invasive ductal carcinoma (IDC) tissues, ne measured the rates of (CO2)-C-14 production from those t issues by using radiorespirometry expressing the results as initial velocit y (V) in nanomoles of (CO2)-C-14 min(-1) g(-1) of fresh tissues. The Vc dat a were compared with results of the SBR system, which grades up from I to I II. Vc,1 values measured with [1-C-14]glucose increased from 1.99-2.82 for SBR I to 3.90-4.09 for SBR II, finally reaching 4.83-7.04 for SBR III, thus matching clearly the increase of LDC cancerous aggressiveness. Conversely, data obtained from [3,4-C-14]glucose and [6-C-14]glucose decreased with in creasing cancer stage: i.e., with [3,4-C-14]glucose, Vc,3,4 values were 5.7 9-9.34 for SBR I, 4.45-4.84 for SBR II, and 2.35-1.90 for SBR III; with [6- C-14]glucose, the corresponding Vc,6 values were 1.33-1.90, 1.33-1.31, and 0.72-0.79. The Vn,1/Vn,6 ratios were close to unity for normal tissues and for noncancerous tissues surrounding SBRI tumors. For cancerous tissues, ho wever, the Vc,1/Vc,6 ratios were 1.5, 2.9, and 6.1-9.8 in IDC tissues grade d as SBR I, II, and III, respectively. The results suggest the possible use of radiorespirometry as a tool to assess LDC aggressiveness.