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Parathyroid carcinoma (PCa) is a rare endocrine neoplasia that typically has unfavourable outcomes. The contribution of long non-coding RNAs (lncRNAs) to the development of malignant and benign parathyroid tumours remains largely unknown. In this study, we explored transcriptomic profiling of lncRNA and mRNA expression in 6 PCa, 6 parathyroid adenoma (PAd) and 4 normal parathyroid (PaN) tissues. In total, 2641 lncRNA transcripts and 2165 mRNA transcripts were differentially expressed between PCa and PAd. Enrichment analysis demonstrated that dysregulated transcripts were involved mainly in the extracellular matrix (ECM)–receptor interaction and energy metabolism pathways. Bioinformatics analysis suggested that ATF3, ID1, FOXM1, EZH2 and MITF may be crucial to parathyroid carcinogenesis. Series test of cluster analysis segregated differentially expressed lncRNAs and mRNAs into several expression profile models, among which the ‘plateau’ profile representing components specific to parathyroid carcinogenesis was selected to build a co-expression network. Seven lncRNAs and three mRNAs were selected for quantitative RT-PCR validation in 16 PCa, 41 PAd and 4 PaN samples. Receiver-operator characteristic curves analysis showed that lncRNA PVT1 and GLIS2-AS1 yielded the area under the curve values of 0.871 and 0.860, respectively. Higher hybridization signals were observed in PCa for PVT1 and PAd for GLIS2-AS1. In conclusion, the current evidence indicates that PAd and PCa partially share common signalling molecules and pathways, but have independent transcriptional events. Differentially expressed lncRNAs and mRNAs have intricate interactions and are involved in parathyroid tumourigenesis. The lncRNA PVT1 and GLIS2-AS1 may be new potential markers for the diagnosis of PCa.

Circular RNAs (circRNAs) are a new class of RNA involved in multiple human malignancies. However, limited information exists regarding the involvement of circRNAs in gastric carcinoma (GC). Therefore, we sought to identify novel circRNAs, their functions and mechanisms in gastric carcinogenesis. We analyzed next-generation RNA sequencing data from GC tissues and cell lines, identifying 75,201 candidate circRNAs. Among these, we focused on one novel circRNA, circNF1 , which was upregulated in GC tissues and cell lines. Loss- and gain-of-function studies demonstrated that circNF1 significantly promotes cell proliferation. Furthermore, luciferase reporter assays showed that circNF1 binds to miR-16, thereby derepressing its downstream target mRNAs, MAP7 and AKT3. Targeted silencing or overexpression of circNF1 had no effect on levels of its linear RNA counterpart, NF1. Taken together, these results suggest that circNF1 acts as a novel oncogenic circRNA in GC by functioning as a miR-16 sponge.

Docetaxel (DTX)-based chemotherapy significantly eliminates rest cancerous cells and decreases the risk of death, thus remaining the mainstay of treatment for operable breast cancer (BCa). However, resistance or incomplete response to DTX occurs frequently, resulting in disease recurrence and poor prognosis. There is an urgent need to identify and understand the key factors and corresponding molecular bases driving this complicated pathogenesis. Herein, both data mining and profiling analysis using clinical BCa biopsies showed that expression levels of the nuclear receptor subfamily 2, group F, member 6 (NR2F6), a recently characterized central transcription factor for cancer immune surveillance, were significantly downregulated in DTX-resistant BCa. This downregulation, possibly regulated by leptin signaling, predicted a poor postoperative chemotherapy survival in DTX-resistant BCa. In both genetically engineered cell models and patient-derived xenograft models, we provided evidence that BCa cells with insufficient NR2F6 expression were less responsive to DTX treatment. Mechanistically, NR2F6 functioned as a potent corepressor of platelet-derived growth factor B receptor gene (PDGFRB) transcription by recruiting HDAC2 onto the PDGFRB promoter. Stable PDGFRB inhibition ameliorated NR2F6 deficiency-impaired response to DTX in BCa cells, indicating that NR2F6’s effect on DTX response is mediated, at least in part, through transcriptional repression of PDGFRB. Collectively, our findings define NR2F6 as an negative regulator of cell survival and DTX resistance, probably by serving as a convergent point linking leptin signaling and PDGF-B/PDGFRβ axis, in BCa cells.