[Etiology and pathogenesis of primary hyperparathyroidism.]

Area of Science:

• Endocrinology
• Genetics
• Calcium Metabolism

Background:

• Primary hyperparathyroidism (pHPT) is a common endocrine disorder characterized by hypercalcemia due to impaired calcium regulation.
• The primary causes of pHPT include parathyroid adenoma (most common), hyperplasia, and carcinoma.
• While often sporadic, pHPT can also be familial (FHPT), linked to specific gene mutations.

Purpose of the Study:

• To review the genetic underpinnings and contributing factors in the etiology and pathogenesis of primary hyperparathyroidism.
• To highlight the role of specific signaling pathways and molecular defects in pHPT development.
• To underscore the impact of vitamin D status and calcium-sensing receptor (CaSR) function on pHPT.

Main Methods:

• Literature review of genetic factors and molecular pathways involved in pHPT.
• Analysis of the roles of CCND1, MEN1, and CaSR signaling pathways.
• Examination of the influence of vitamin D insufficiency and CaSR dysfunction.

Main Results:

• Gene abnormalities in cyclin D1 signaling (CCND1, CDC73, CDKN1B), Wnt/β-catenin signaling (MEN1), and calcium-sensing receptor signaling (CaSR, GNA11, AP2S1) are implicated in pHPT.
• Vitamin D insufficiency/deficiency and CaSR dysfunction contribute to the severity of pHPT.
• Adenomas are the most frequent cause (80%), followed by hyperplasia (15%) and cancer (1-5%).

Conclusions:

• Understanding the genetic basis and contributing factors of pHPT is crucial for advancing treatment strategies.
• Further research into the etiology and pathogenesis of pHPT will enhance our comprehension of calcium regulation.
• Elucidation of these mechanisms may lead to novel therapeutic interventions for hypercalcemia and related disorders.