DEAD-Box Helicase 27 Triggers Epithelial to Mesenchymal Transition by Regulating Alternative Splicing of Lipoma-Preferred Partner in Gastric Cancer Metastasis

DEAD-box helicase 27 (DDX27) was previously identified as an important mediator during carcinogenesis, while its role in gastric cancer (GC) is not yet fully elucidated. Here, we aimed to investigate the mechanism and clinical significance of DDX27 in GC. Public datasets were analyzed to determine DDX27 expression profiling. The qRT-PCR, Western blot, and immunohistochemistry analyses were employed to investigate the DDX27 expression in GC cell lines and clinical samples. The role of DDX27 in GC metastasis was explored in vitro and in vivo. Mass spectrometry, RNA-seq, and alternative splicing analysis were conducted to demonstrate the DDX27-mediated molecular mechanisms in GC. We discovered that DDX27 was highly expressed in GCs, and a high level of DDX27 indicated poor prognosis. An increased DDX27 expression could promote GC metastasis, while DDX27 knockdown impaired GC aggressiveness. Mechanically, the LLP expression was significantly altered after DDX27 downregulation, and further results indicated that LPP may be regulated by DDX27 via alternative splicing. In summary, our study indicated that DDX27 contributed to GC malignant progression via a prometastatic DDX27/LPP/EMT regulatory axis.

Automated summary

DDX27 is highly expressed in gastric cancer and is associated with poor prognosis. It promotes gastric cancer metastasis, while knockdown of DDX27 weakens the aggressiveness of gastric cancer. Furthermore, our study suggests that DDX27 may mediate the molecular mechanisms in gastric cancer through regulation of alternative splicing of LPP.