Pituitary Tumor

The pituitary gland is a pea-sized endocrine gland located at the base of the brain. The pituitary gland regulates and controls the secretion of hormones from other endocrine glands, which in turn regulate many bodily processes. These hormones include growth hormone (GH), thyroid stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), and prolactin. The cause of pituitary tumors is not known and most pituitary tumors are located in the anterior pituitary gland and are usually benign (non-cancerous). About 75% of pituitary tumors secrete hormones. When the tumor produces excessive amounts of one or more hormones, gigantism or acromegaly, hyperthyroidism, Cushing's syndrome, and prolactinoma may occur. As pituitary tumors grow, some hormone-secreting cells of the pituitary gland may be destroyed, leading to symptoms associated with inadequate production of the suppressed hormone (hypopituitarism).

Pituitary tumors are not usually cancerous and therefore do not spread to other parts of the body. However, they can put pressure on the brain, which can lead to serious problems. It is important to note that the presence of invasive behavior alone is not enough to define a malignant tumor. Very rare pituitary cancers are characterized by the presence of craniospinal and/or systemic metastases. Despite previous surgery and radiation therapy, a large percentage of invasive pituitary tumors continue to progress and therefore require additional treatment options. Alfa Cytology can help you explore the future of drug treatment for pituitary tumors.

• Epidermal growth factor (EGF)

The EGF system is a family of transmembrane tyrosine kinase receptors known as EGFR, ErB1, or HER that when bound to a ligand, form homodimers and/or heterodimers and deliver intracellular signals via an intrinsic kinase structural domain. In human prolactinomas (PRLomas), EGFR expression is heterogeneous. In preclinical models, EGFR antagonists reduce cell proliferation, block PRL gene expression and reduce PRLomas volume and secretion levels in murine xenografts. Several reports suggest that inhibition of EGFR in dopamine agonist (DA)-resistant and/or aggressive human PRLomas may be an effective therapeutic option.

• Transforming growth factor (TGF)-β signaling pathway

TGF is another well-known cytokine with multiple roles, including the regulation of lactogenic cell proliferation and its hormone secretion. the TGF-β signaling cascade is triggered by the binding of TGFβ1, TGFβ2 or TGFβ3 to type II TGFβ receptors, which in turn recruit and phosphorylate type I TGFβ receptors to form complexes. Subsequently, type I TGFβ receptors lead to the formation of heterodimeric complexes between smad2, smad3, and smad4, which eventually translocate to the nucleus to regulate the expression of various genes. Previous studies have shown that TGFβ1 can inhibit lactogen (PRL) secretion and the proliferation of lactogenic cells like dopamine. The results also suggest that TGFβ1 is at least partially involved in the regulation of dopamine on lactocytes, i.e. inhibiting PRL secretion and controlling lactocyte proliferation. This suggests that restoring local TGFβ1 activity may be an interesting approach to the treatment of PRLomas that are resistant to DA.

• MAPK kinase and Pi3K/AKT/mTOR signaling pathways

The RAF/MEK/ERK and Pi3K/AKT/mTOR signaling pathways play an important role in cell growth and metabolism, as well as in tumorigenesis. In pituitary neuroendocrine tumors, AKT, located at the crossroads of the mTOR pathway, is overexpressed and activated. On the other hand, the expression of MEK1/2 and ERK1/2, phosphorylated forms downstream of the MAPK signaling pathway, is significantly higher in PRLomas than in the normal pituitary. The study suggests that the mTOR signaling pathway may be involved in the response of PRLomas to DA. In addition to the response to DA, the mTOR signaling pathway has recently been identified as a promoter of pituitary tumor development in PRLomas. In vitro experiments have shown that mTOR inhibitors can effectively treat PRL tumor cells.

There is a growing interest in developing drug therapies for the control of pituitary tumor growth and/or hormone overproduction, and Alfa Cytology will help you to better understand the molecular features of pituitary tumor secretion and proliferation mechanisms to provide the best support for research into multiple types of brain tumor disease. We are ready to provide you with a wide range of technical services, so please feel free to open a project contact.