Association between β-arrestin-2 and filamin-A gene variations with medical treatment response in acromegaly patients

BACKGROUND: Acromegaly is a disease that occurs as a result of excessive growth hormone caused by pituitary adenomas. Some acromegaly patients show resistance to somatostatin analog (SSA) treatment. Filamin-A (FLNA) and β-arrestins are thought to play a role in the response to SSAs. We aimed to investigate the relationship between FLNA-rs782079491 and β-arrestin-2-rs34230287 single-nucleotide polymorphisms and disease risk, as well as treatment response in patients with acromegaly in the Turkish population. METHODS: The genotypes of 110 acromegaly patients and 99 controls were determined by real-time PCR. The genotype distributions were compared with clinical data on the disease. RESULTS: There was no association between the β-arrestin-2 gene polymorphism and the response to SSA treatment in acromegaly patients. For responder patients to SSAs, the β-arrestin-2-rs34230287 CT+TT genotype was associated with higher microadenoma as compared with the CC genotype (P=0.017). The FLNA polymorphism was not observed in the study group. CONCLUSIONS: We showed that there was no association between the polymorphic genotypes of FLNA and β-arrestin-2 genes with acromegaly disease and SSAs response in the Turkish population. However, there was a relationship between β-arrestin-2 and some of the clinical characteristics. Furthermore, the CC genotype and the C allele are risk factors associated with tumor growth rate in acromegaly patients.