Background
The ORMDL1 gene is known as a crucial negative regulator of sphingolipid biogenesis. However, the ORMDL1 gene has rarely been studied in a tumor-related context. Therefore, its prognostic value and functional significance in colorectal cancer (CRC) remain to be explored.
Conclusion
ORMDL1 is upregulated and may serve as a biomarker to predict favourable outcomes in colorectal cancer.
Methods
TCGA CRC cohort analysis, qRT-PCR, and immunohistochemistry (IHC) were used to examine the ORMDL1 expression level. The association between ORMDL1 expression and various clinical characteristics was analyzed by chi-square tests. The overall survival (OS) of CRC patients was analyzed by Kaplan-Meier analysis. In vitro and in vivo cell-based assays were performed to explore the role of ORMDL1 in cell proliferation, invasion and migration. Transcriptional changes in cells with either ORMDL1 knockdown or overexpression were compared and analyzed.
Results
ORMDL1 was upregulated in CRC tissues in both the TCGA and our cohort. Interestingly, its expression was significantly lower in patients with metastasis than in patients without metastasis, and the high expression group had longer OS than the low expression group. Knockdown of ORMDL1 expression can promote proliferation, colony formation and invasion, while attenuating migration in CRC cell lines. In contrast, forced overexpression of ORMDL1 reduced cell proliferation, colony formation and invasion, while enhancing cell migration. Stable knockdown of ORMDL1 can promote cancer cell proliferation in vivo to some extent. Finally, Rho GTPase activity was influenced by ORMDL1, and the expression of ORMDL1 was enhanced by DTT treatment.