TFRC and cancer: AFt is preferentially internalized by cells following TfR1-mediated endocytosis,25 hence AFt encapsulation of active agent provides a tool for their selective uptake by cells expressing TfR1, hence decreasing possible side effects.34 Cellular TfR-1 protein was detected in lysates of HCT-116 and MiaPaCa-2 cancer cells, and was below detectable levels in non-tumorigenic fibroblast MRC-5 cells (Fig. 2a).