High throughput circRNA sequencing analysis reveals novel insights into the mechanism of nitidine chloride against hepatocellular carcinoma

Abstract

Nitidine chloride (NC) has been demonstrated to have an anticancer effect in hepatocellular carcinoma (HCC). However, the mechanism of action of NC against HCC remains largely unclear. In this study, three pairs of NC-treated and NC-untreated HCC xenograft tumour tissues were collected for circRNA sequencing analysis. In total, 297 circRNAs were differently expressed between the two groups, with 188 upregulated and 109 downregulated, among which hsa_circ_0088364 and hsa_circ_0090049 were validated by real-time quantitative polymerase chain reaction. The in vitro experiments showed that the two circRNAs inhibited the malignant biological behaviour of HCC, suggesting that they may play important roles in the development of HCC. To elucidate whether the two circRNAs function as “miRNA sponges” in HCC, we identified circRNA-miRNA and miRNA-mRNA interactions by using the CircInteractome and miRwalk, respectively. Subsequently, 857 miRNA-associated differently expressed genes in HCC were selected for weighted gene co-expression network analysis. Module Eigengene turquoise with 423 genes was found to be significantly related to the survival time, pathology grade and TNM stage of HCC patients. Gene functional enrichment analysis showed that the 423 genes mainly functioned in DNA replication- and cell cycle-related biological processes and signalling cascades. Eighteen hubgenes (SMARCD1, CBX1, HCFC1, RBM12B, RCC2, NUP205, ECT2, PRIM2, RBM28, COPS7B, PRRC2A, GPR107, ANKRD52, TUBA1B, ATXN7L3, FUS, MCM8 and RACGAP1) associated with clinical outcomes of HCC patients were then identified. These findings showed that the crosstalk between hsa_circ_0088364 and hsa_circ_0090049 and their competing mRNAs may play important roles in HCC, providing interesting clues into the potential of circRNAs as therapeutic targets of NC in HCC.

The clinical value and potential molecular mechanism of the downregulation of MAOA in hepatocellular carcinoma tissues

“…As demonstrated previously, a decreased MAOA was detected in HCC patients and correlated with poor prognosis. Our previous studies have confirmed the anti‐HCC effect of NC 34,35,37 . In this study, in vivo experiment showed that the tumor volumes were reduced and the MAOA expression level was significantly elevated in the NC‐treated group compared with the control group.…”

“…Our team has been studying the biological function NC has on HCC for a period. Previous in vitro and in vivo studies have verified that TCM NC exhibits a strong anti‐HCC capability by mediating complicated mechanisms, namely TF‐miRNA‐mRNA axis, circRNA‐miRNA‐mRNA network, andJAK1/STAT3 cascade signaling inhibition 34‐38 . Given the role that MAOA plays in HCC, we supposed that NC could exert its anti‐tumor effect partially by influencing the expression of MAOA .…”

“…To date, some mechanisms of the suppressor role of NC in HCC have been proved. Based on in vitro and in vivo studies, TF‐miRNA‐mRNA axis and circRNA‐miRNA‐mRNA network were established to provide clues on the role of NC in HCC 34,35 . Another in vitro and in vivo experiment confirmed that the therapeutic effect of NC on HCC correlated with the upregulation of p53 and Bcl‐2 36 .…”

Circular RNA circSIPA1L1 Contributes to Osteosarcoma Progression via the miR-411-5p/RAB9A Axis

“…As a newly emerging member of the non-coding RNA family, circRNAs have gained extensive attention recently, owing to the advances in bioinformatics approaches and widespread use of transcriptome sequencing (22,23). Accumulating research has suggested that circRNAs are involved in a variety of disease processes owing to their unique characteristics, such as high abundance, structural stability, and conservation across species (24,25).…”

The role of noncoding RNAs in epithelial cancer

“…The research on circRNAs is still in his infancy and their specific functions in several physiological processes and in the pathogenesis of human diseases is still largely unknown. However, recently high-throughput sequencing studies on clinical tumor samples showed a deregulation of circRNAs expression in tumors 138,139 . In particular, their downregulation has been described in proliferative cells across different tumor types, indicating that some circRNAs may have tumor suppressive roles.…”