Abstract
BackgroundThe homobox (HOX) gene family as a transcription factor encoding a specific nuclear protein is essential for embryonic development, differentiation, and homeostasis. The role of HOXB3 protein varies in different tumors. This study aims to explore the role of the HOXB3 gene in breast cancer.MethodDifferentiated expressed genes were screened by analyzing metastatic breast cancer gene chip data in TCGA and GEO database. The function of selected HOXB3 gene was also analyzed by GEPIA, Kaplan-Meier Plotter, Breast Cancer Gene-Expression Miner and metascape. Molecular biology methods such as qRT-PCR, western blot and IF was used to verify bio-informatics findings.ResultsBoth bio-informatics analyses and western blot showed that HOXB3 was lost in breast cancer compared to normal breast tissue. Survival analysis also showed that lower expression of HOXB3 was associated with poor prognosis. Bio-informatics analyses further showed that HOXB3 was positively correlated with hormone receptors. qRT-PCR, immunofluorescence and western blot also confirmed that HOXB3 had the highest expression in the immortalized breast epithelial cell line MCF-10A, lower in luminal breast cancer cell line T47D and the lowest in triple negative breast cancer (TNBC) cell line MDA-MB-231. Metascape for GO analysis of GEO data provided possible mechanism that HOXB3 could positively regulate cell adhesion, inhibit cell proliferation and activate immune response in breast cancer, and considered that HOXB3 might cause cell malignant transformation through the above pathways.ConclusionIn summary, HOXB3 expression was decreased in breast cancer, especially in hormone receptor-negative breast cancer. The lower expression of HOXB3 was associated with poor prognosis. It might become a new biomarker to predict prognosis of breast cancer.
Role of Poly (ADP-Ribose) Polymerase inhibitors beyond BReast CAncer Gene-mutated ovarian tumours: definition of homologous recombination deficiency?
