Figure 2From: Possible role of membrane gamma-glutamyltransferase activity in the facilitation of transferrin-dependent and -independent iron uptake by cancer cells.Correlation between membrane GGT activity of 4 human tumor cell lines and the corresponding GGT-stimulatable uptake of transferrin-bound iron. Data shown are means ± SEM of 3–5 experiments. The logarithmic correlation curve shown is statistically significant (r = 0.99).Back to article page