Interestingly, while syndromic conditions are associated with genes involved in cell-cycle and/or transcription, isolated pituitary adenomas and sporadic cases are mainly correlated with genes involved in calcium and cAMP signaling [50], such as the aforementioned AIP (Aryl Hydrocarbon Receptor Interacting Protein), GPR101 (G Protein-Coupled Receptor 101), PRKAR1A (Protein Kinase CAMP-Dependent Type I Regulatory Subunit Alpha), or GNAS (α subunit of the stimulatory G protein) specifically in growth hormone (GH) PitNETs. Here, GPR101 is linked to pituitary gland adenoma.