The study aims to characterize the
circular RNA (
circRNA) expression profile that is functionally related with the invasiveness of
papillary thyroid microcarcinoma (PTMC).A total of 13 pairs of female patients with non-invasive PTMC or
lymph node metastasis PTMC (PTMC (L)) were included and the serum
RNA was obtained.
CircRNA microarray was performed to identify the
circRNA expression profile. Real time-PCR was used to verify
circRNA expression. Bioinformatic approaches were adopted to annotate the function of differentially expressed
circRNAs and construct the
circRNA-
miRNA-
mRNA network.In total, 400 significantly upregulated and 290 significantly downregulated
circRNAs were identified in PTMC (L) compared with PTMC. Among them, 10
circRNAs were selected and validated by real time-PCR. Putative
microRNAs (
miRNAs) that could bind to the differentially expressed
circRNAs were predicted. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses of target genes of the differentially expressed
circRNAs revealed that these
circRNAs may play an important role in
lymph node metastasis. Finally,
circRNA targeted
miRNAs were predicted and a
circRNA-
miRNA-
mRNA network was constructed for hsa_
circRNA_404686.Our results showed that several
circRNAs, such as hsa_
circRNA_404686, may serve as promising diagnostic marker for PTMC (L) in female.