In a very early study by Bjurholm et al., SP (and NPY) was not able to induce a cAMP response in rat osteosarcoma cell lines UMR-101-01 and ROS 17/2.8, the human osteosarcoma cell line Saos-2, a mouse calvarial pre-osteoblastic cell line, MC3T3-E1, and in primary mouse neonatal calvarial bone cells, indicating a minor role for SP in osteoblast function regulation [85]. The gene discussed is TFF2; the disease is osteosarcoma.