TCF21 and neoplasm: Our data showing that G and F/R cellsrespond differently to ectopic POD-1 expression emphasize the functional differencesbetween the outer and inner zones of the adrenal cortex, and support the hypothesisthat SF-1 is regulated by POD-1/Tcf21 in normal adrenocortical cellslacking the alterations in cellular physiology found in tumor cells.