In this study, we report the expression of the ErbB family of receptors and the endogenous production of EGFR ligand mRNA by two human lung SCC cell lines, RWGT2 and HARA, that have been reported previously to produce hypercalcaemia in athymic mice (Guise et al, 1993; Iguchi et al, 1996). Here, EGFR is linked to Hypercalcemia.