Introduction: DEAD-box helicase 27 (DDX27) belongs to DEAD-Box nucleic acid helicase family. The function of DDX27 in hepatocellular carcinoma (HCC) remain enigmatic. In light of this, we tried to investigate the regulatory role and underlying mechanism of DDX27 in HCC. Materials and methods: DDX27 expression levels were detected by qRT-PCR, Western blot and immunohistochemistry assays in HCC tissues and cells. Colony formation, CCK-8, growth curve, wound healing and transwell assays were conducted to investigate the effect of DDX27 on the proliferation and metastasis of HCC cells. RNA-sequencing was performed to detect the effect of DDX27 on downstream signaling pathway. The effect of DDX27 on HCC progression was evaluated using in vivo murine xenograft model. Results: we found an increased expression of DDX27 in HCC tissues with comparison to its para-tumor tissues. The high expression levels of DDX27 were associated with poor prognosis in HCC patients. DDX27 upregulation promoted cell metastasis. Mechanistic studies suggested that DDX27 overexpression induces the major vault protein (MVP) expression and enhances the phosphorylation levels of ERK1/2. Inhibition of ERK pathway impaired the cellular metastastic abilities induced by DDX27. The induction of DDX27 in HCC progression was further confirmed from tumors in mouse model. Conclusion: our results disclose a novel mechanism by which DDX27 enhances ERK signaling during HCC progression. DDX27 might be used in targeted therapy for HCC patients.

Tyrosine phosphatase receptor type N (PTPRN) plays an important role in the regulation of the secretion pathways of various neuroendocrine cells. Moreover, PTPRN was demonstrated to play a crucial role in the initiation and progression of the signalling cascade regulating cell function. In this study, fifty-seven glioma patients were enrolled for clinical and prognostic analyses. The cell phenotype was determined by cell proliferation and migration assays. RNA-seq, co-IP and mass spectrometry were used to study the molecular mechanism of the effects of PTPRN on cell proliferation and metastasis. The result showed that High expression of PTPRN indicated a poor prognosis of high-grade glioma. PTPRN downregulation reduced the proliferation and migration of glioma cells, and PTPRN overexpression induced the proliferation and migration of glioma cells. PTPRN knockdown decreased tumor growth in a mouse xenograft model. Effect of PTPRN knockdown on the transcriptome was studied in U87 glioma cells. PTPRN activated the PI3K/AKT pathway by interacting with HSP90AA1. In conclusion, PTPRN is an important proliferation- and metastasis-promoting factor. Reducing the expression of PTPRN in glioma cells can be used as a potential therapeutic strategy.