TTR and meningioma: [130] tested loss of the potential meningioma tumor suppressor receptor-like density-enhanced phosphatase-1 (DEP-1) [99], encoded by PTPRJ. They showed no TTR in PTPRJ−/− transgenic mice alone but raised TTRs ranging from 6% (0–27%) in their Nf2Flox2/Flox2 to 25% (13–40%) in Nf2(flox2/flox2);Ptprj(−/−), all over the same time period of one year for typical meningiomas with whorls and psammoma bodies, thus suggesting an interaction between the two genes in meningioma development.