Related Experiment Video
Updated: Sep 17, 2025
Employing Digital Droplet PCR to Detect BRAF V600E Mutations in Formalin-fixed Paraffin-embedded Reference Standard Cell Lines
Published on: October 8, 2015
DICER1 mutations in Bethesda category II, III, and IV thyroid nodules: A mutually exclusive relationship with
Yulian Wang1,2, Guangqi Li3, Weimao Kong3
1Department of Pathology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, China.
Background:
This study aimed to investigate the prevalence and cytological features of Dicer 1, Ribonuclease III (DICER)-mutant fine-needle aspiration (FNA) specimens in thyroid nodules classified as Bethesda II, III, and IV categories. The authors also sought to explore the relationship between DICER1 and BRAFV600E mutations in Bethesda III thyroid nodules.
Methods:
The authors collected a series of consecutive FNA cases diagnosed as Bethesda category II, III, and IV from a medical center over the course of 1 year. DICER1 exons 24 and 25 and TERT promoter mutations were detected by Sanger sequencing in all cases, and BRAFV600E mutations were detected by amplification refractory mutation system PCR in Bethesda III and IV cases.
Results:
A total of 899 patients were included in the study. DICER1 mutations were identified in 52 patients: 20 in Bethesda category II (6.2%, 20 of 322), 25 in Bethesda category III (4.9%, 25 of 510), and seven in Bethesda category IV (10.4%, 7 of 67). Among the 510 Bethesda III FNA samples, 76 harbored the BRAFV600E mutation and 25 harbored DICER1 mutations. BRAFV600E and DICER1 mutations were mutually exclusive. In Bethesda category II and III cases, patients with DICER1-mutant nodules were younger and had larger nodule volumes compared to those without DICER1 mutations. All DICER1-mutant Bethesda III FNAs were classified as atypia of undetermined significance (AUS)-other. TERT promoter mutations (c. -118G>T and c. -144 C>T) were identified in two FNA samples.
Conclusion:
The findings of this study suggest that DICER1-mutant nodules are unlikely to be BRAF-mutant carcinomas. Further study of the molecular characteristics of DICER1-mutant FNAs will contribute to more accurate cytological diagnosis.
Related Concept Videos
02:23Abnormal Proliferation
01:20The Retinoblastoma Gene
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
01:05Cancer-Critical Genes II: Tumor Suppressor Genes
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
02:38The Ras Gene
Ras is a...
02:15M-Cdk Drives Transition Into Mitosis
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
02:21Cancers Originate from Somatic Mutations in a Single Cell