Background : Homeobox B4 (HOXB4) is correlated with poor prognosis of various cancer types.

Background: Homeobox B4 (HOXB4) is associated with the poor prognosis of various cancer types. However, how HOXB4 promotes ovarian cancer (OV) progression remains to be determined. Methods：The Cancer Genome Atlas (TCGA) database indicated that high level of HOXB4 in OV was correlated with poor prognosis. The biological functions of HOXB4 were confirmed through a colony formation, migration, and invasion assay. The effect of HOXB4 on the expression of EMT and cancer stem cell markers was detected. The transcriptional target of HOXB4 was DHDDS, which was detected by a ChIP assay. A xenograft tumor model was performed in nude mice to detect the role of HOXB4 in tumor proliferation and metastasis. Results：Results showed that the expression of HOXB4 was higher in OV tissues than in normal tissues and correlated with the poor prognosis of OV. HOXB4 knockdown suppressed the proliferation and invasion ability of OV cells in vitro. Conversely, these effects were enhanced by the up-regulation of HOXB4 in OV cells. The binding of two DNA motifs through HOXB4 regulated DHDDS expression and contributed to the malignant progression of OV. The role of HOXB4 in promoting tumor proliferation and metastasis was verified in mice. Further investigation revealed that HOXB4 triggered Snail and Zeb1 expression. Conclusion: Overall, HOXB4 overexpression was remarkably correlated with the poor prognosis of OV. HOXB4 up-regulated DHDDS, which co-contributed to the enhancer proliferation and invasion of OV cells, thus accelerating the malignant progression of OV.

Background : Homeobox B4 (HOXB4) is correlated with poor prognosis of various cancer types. However, how HOXB4 promotes ovarian cancer (OV) progression remains unclear. Methods : The Cancer Genome Atlas (TCGA) database indicated that a high level of HOXB4 in OV was correlated with poor prognosis. The biological functions of HOXB4 were confirmed by colony formation, migration, and invasion assays. The effect of HOXB4 on the expression of EMT cell markers was determined. The transcriptional target of HOXB4 was DHDDS, which was detected by a ChIP assay. A xenograft tumor model was generated in nude mice to detect the role of HOXB4 in tumor proliferation and metastasis. Results : The results showed that HOXB4 protein levels were higher in OV tissues than in normal tissues and correlated with poor prognosis of OV. HOXB4 reduction inhibited the proliferation and invasion ability of OV cells in vitro. Conversely, these effects were enhanced by the upregulation of HOXB4 in OV cells. The binding of HOXB4 to two DNA motifs regulated DHDDS expression and contributed to the malignant progression of OV. The role of HOXB4 in contributing to tumor development in vivo was verified in mice. Further results indicated that HOXB4 induced Snail and Zeb1 expression. Conclusion : Overall, HOXB4 overexpression was remarkably correlated with poor prognosis of OV. Mechanistically, HOXB4 enhances the proliferation and invasion of tumor cells by activating DHDDS, thereby promoting the malignant progression of OV.