Clinical MEN-1 Among a Large Cohort of Patients With Acromegaly
JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM
Authors: Nachtigall, Lisa B.; Guarda, Francisco J.; Lines, Kate E.; Ghajar, Alireza; Dichtel, Laura; Mumbach, Giselle; Zhao, Wenxiu; Zhang, Xun; Tritos, Nicholas A.; Swearingen, Brooke; Miller, Karen K.; Thakker, Rajesh, V
Abstract
Context: Clinical multiple endocrine neoplasia type 1 (MEN-1) is diagnosed by the presence of at least 2 MEN-1-associated tumors. Many patients with acromegaly and clinical MEN-1 yield negative testing for MEN1 mutations. While cases of acromegaly and primary hyperparathyroidism (PHP) with negative genetic testing have been reported, its prevalence among patients with acromegaly is undetermined, and the clinical presentation has not been well characterized. Objectives: The main goals of this study are: (1) To determine the prevalence of clinical MEN-1 with PHP in patients with acromegaly and characterize their clinical features; and (2) to evaluate the genetic basis for the coexistence of acromegaly and PHP. Design: Retrospective record review and genetic analysis. Setting: Clinical Research Centers. Participants: 414 patients with acromegaly. Interventions: Clinical evaluation and DNA sequencing for MEN1, CDKN1A, CDKN1B, CDKN2B, CDKN2C, and A/P genes. Main outcome measurements: Clinical and genetic analysis. Results: Among patients with acromegaly, clinical MEN-1, as defined by the presence of at least one other MEN-1-associated tumor, was present in 6.6%. PHP occurred in 6.1%; more than half had parathyroid hyperplasia. DNA sequencing was unrevealing for genetic mutations, except for 1 case of a CDC73 mutation. Acromegaly was diagnosed at an older age with a higher prevalence of malignancies (specifically breast and thyroid) in patients with coexisting PHP than those with isolated acromegaly. Conclusions: A distinct phenotype is described in patients with clinical MEN-1 and negative genetic testing for mutations previously associated with this syndrome. Further studies are needed to identify other genes that may explain the association between PHP and acromegaly.
Expression and DNA methylation profiles of EZH2-target genes in plasma exosomes and matched primary tumor tissues of the patients with diffuse large B-cell lymphoma
CLINICAL & TRANSLATIONAL ONCOLOGY
Authors: Baris, I. C.; Hacioglu, S.; Turk, N. S.; Cetin, G. O.; Zencir, S.; Bagci, G.; Caner, V.
Abstract
Aims Diffuse large B-cell lymphoma (DLBCL) is the most common type of aggressive lymphoma. This study was designed to compare epigenetic alterations observed in Enhancer of Zeste Homolog 2 (EZH2)-target genes between plasma-derived exosomes and primary tumors in DLBCL patients. Main methods Exosomes were isolated from plasma of 21 DLBCL patients and 21 controls. We analyzed the methylation status of the target genes using methylation-specific PCR. We also examined whether the exosomes and the tumor samples contained transcripts of the target genes. Key findings We found that CDKN2A and CDKN2B were methylated in both plasma exosomes and primary tumor tissue samples. None of the transcripts were found in the exosomes except CDKN1B which was expressed in 8 (38%) of the exosome samples. Significance This study showed that plasma exosomes might preferably package certain target molecules from primary tumors and the exosomes containing dual methylated DNAs of CDKN2A and CDKN2B, or CDKN1B transcript may contribute to DLBCL pathogenesis.