Table 1

Ligands	Receptors
Ga, In, Fe	Transferrin, Lactoferrin
Tl, K	Na, K ATPase
Glucose, FDG	Direct G-Protein Activation
Substance P	Amino acid
a-methyltyrosine	Estrogen
Estrogen, analogs, tamoxifen	Sigma
Lodobenzamides	Melanocyte
For more detailed information see reference. [23]

Table 1: Selected receptors, and their corresponding ligands that are over expressed in tumour cells.