Aim Circular RNAs (circRNAs) are a novel class of noncoding RNAs and are conserved in various species. Although numerous circRNAs have been identified, their role in cancer remains unclear. Methods The expression of circTMEM181 in 90 paired human hepatocellular carcinoma (HCC) and adjacent nontumor tissues were detected using quantitative reverse transcription–polymerase chain reaction. Transwell assay was performed for functional analysis of HCC cell migration and invasion. Luciferase reporter assay was used to verify the combination of circTMEM181 and miR‐519a‐5p. Results In this study, we identified a novel circRNA, named circTMEM181, was downregulated in HCC tissues. Decreased expression of circTMEM181 was associated with shorter overall survival of patients with HCC. CircTMEM181 overexpression reduced HCC cell migration and invasion abilities, while circTMEM181 knockdown increased cell motility. Mechanically, circTMEM181 could directly bind to miR‐519a‐5p and subsequently upregulate ARHGAP29 protein expression. Conclusion These data provide the first evidence of clinical significance and function of circTMEM181, and suggest the circTMEM181/miR‐519a‐5p/ARHGAP29 axis in HCC development.

Background Esophageal squamous cell carcinoma (ESCC) is a highly heterogeneous cancer that lacks comprehensive understanding and effective treatment. Although multi-omics study has revealed features and underlying drivers of advanced ESCC, research on molecular characteristics of the early stage ESCC is quite limited. Materials and methods We presented characteristics of genomics and transcriptomics in 10 matched pairs of tumor and normal tissues of early ESCC patients in the China region. Results We identified the specific patterns of cancer gene mutations and copy number variations. We also found a dramatic change in the transcriptome, with more than 4,000 genes upregulated in cancer. Among them, more than one-third of HOX family genes were specifically and highly expressed in early ESCC samples of China and validated by RT-qPCR. Gene regulation network analysis indicated that alteration of Hox family genes promoted the proliferation and metabolism remodeling of early ESCC. Conclusions We characterized the genomic and transcriptomic landscape of 10 paired normal adjacent and early ESCC tissues in the China region, and provided a new perspective to understand the development of ESCC and insight into potential prevention and diagnostic targets for the management of early ESCC in China.

Better biomarkers are needed to improve the efficacy of immune checkpoint inhibitors in lung adenocarcinoma (LUAD) treatment. We investigated the plasma extracellular vesicle (EV)-derived long RNAs (exLRs) in unresectable/advanced LUAD to explore biomarkers for immunochemotherapy. Seventy-four LUAD patients without targetable mutations receiving first-line anti-programmed cell death 1 (PD-1) immunochemotherapy were enrolled. Their exLRs were profiled through plasma EV transcriptome sequencing. Biomarkers were analyzed against response rate and survival using pre-and post-treatment samples in the retrospective cohort (n = 36) and prospective cohort (n = 38). The results showed that LUAD patients demonstrated a distinct exLR profile from the healthy individuals (n = 56), and T-cell activation-related pathways were enriched in responders. Among T-cell activation exLRs, CD160 exhibited a strong correlation with survival. In the retrospective cohort, the high baseline EV-derived CD160 level correlated with prolonged progression-free survival (PFS) (P < 0.001) and overall survival (OS) (P = 0.005), with an area under the curve (AUC) of 0.784 for differentiating responders from non-responders. In the prospective cohort, the CD160-high patients also showed prolonged PFS (P = 0.003) and OS (P = 0.014) and a promising AUC of 0.648. The predictive value of CD160 expression was validated by real-time quantitative PCR. We also identified the dynamics of EV-derived CD160 for monitoring therapeutic response. The elevated baseline CD160 reflected a