Expression and subcellular localization of the bromodomain-containing protein 7 is a prognostic biomarker in breast cancer

Tumor- and host-derived heparanase-2 (Hpa2) attenuates tumorigenicity: role of Hpa2 in macrophage polarization and BRD7 nuclear localization

Little attention was given to heparanase 2 (Hpa2) over the last two decades, possibly because it lacks a heparan sulfate (HS)-degrading activity typical of heparanase. Emerging results suggest, nonetheless, that Hpa2 plays a role in human pathologies, including cancer progression where it functions as a tumor suppressor. Here, we examined the role of Hpa2 in cervical carcinoma. We report that high levels of Hpa2 correlate with prolonged survival of cervical carcinoma patients. Strong staining intensity of Hpa2 also correlates with low tumor grade. Overexpression of Hpa2 in SiHa cervical carcinoma cells resulted in tumor xenografts that were two-fold smaller than control tumors. Interestingly, even smaller tumor xenografts were developed by SiHa cells overexpressing the Pro140Arg and Asn543Ile Hpa2 missense mutations that were identified in patients diagnosed with urofacial syndrome (UFS). Utilizing the Ras recruitment system, we identified bromodomain-containing protein 7 (BRD7) to interact with Hpa2 and found that both BRD7 and the Hpa2 mutants are translocated to the cell nucleus in tumors developed by the Pro140Arg and Asn543Ile Hpa2 mutants. Utilizing our newly developed conditional Hpa2-KO mice, we further show that Hpa2 plays a critical role in macrophage polarization; in the absence of Hpa2, macrophages are shifted towards pro-tumorigenic, M2 phenotype. Notably, implanting SiHa cervical carcinoma cells together with Hpa2-KO macrophages promoted tumor growth. These results support, and further expand, the notion that Hpa2 functions as a tumor suppressor, co-operating with another tumor suppressor, BRD7.

PHF20 is a Novel Prognostic Biomarker and Correlated with Immune Status in Breast Cancer

Increasing evidence has demonstrated that enhanced PHF20 expression plays a crucial role in cancer development and progression. However, little is known about the prognostic value of PHF20 expression in breast cancer (BRCA). In this study, we attempted to explore the expression pattern of PHF20 and its associations with prognosis and immune status in BRCA. The gene expression data and clinical information of 1109 BRCA samples were downloaded from TCGA database. The expression level of PHF20 protein was determined using UALCAN and HPA database. Kaplan-Meier method and CIBERSORT algorithm were used to analyze the associations of PHF20 expression with overall survival (OS) and immune microenvironment, respectively. Besides, GSEA analysis was conducted to explore potential biological functions and molecular mechanisms of PHF20 in BRCA. Moreover, starBase database was applied to construct a ceRNA nework. PHF20 was highly expressed in BRCA samples both at the transcriptional and protein level, and was strongly correlated with the OS and immune status. Univariable and multivariate Cox regression analyses identified PHF20 as an independent prognostic factor. Additionally, GSEA analysis showed that high PHF20 expression was closely associated with TGF-β signaling pathway, Wnt signaling pathway, and adherens junction. Furthermore, three ceRNA networks (AC037198.1/hsa-miR-223-3p/PHF20, CBR3-AS1/hsa-miR-223-3p/PHF20, and ZNF561-AS1/hsa-miR-223-3p/PHF20) were identified by starBase analysis. Functional experiments validated that PHF20 knockdown inhibited the cell viability and progression in BRCA cells. PHF20 overexpression was significantly associated with poor prognosis and immune status in BRCA, and could act as a potential novel prognostic biomarker for BRCA.

Upregulation of BRD7 protects podocytes against high glucose-induced apoptosis by enhancing Nrf2 in a GSK-3β-dependent manner

Bromodomain-containing protein 7 (BRD7) is linked to a variety of pathophysiological conditions. However, it is still unclear whether BRD7 is connected with diabetic nephropathy. This research explored the relevance of BRD7 in diabetic nephropathy using high glucose (HG)-stimulated podocytes in vitro. BRD7 expression in podocytes was decreased after HG stimulation. Podocytes with forced BRD7 expression were protected from HG-induced apoptosis, oxidative stress and inflammation. Further data revealed that forced expression of BRD7 led to enhanced nuclear factor erythroid-2-related factor 2 (Nrf2) activation in HG-stimulated podocytes, associated with the upregulation of glycogen synthase kinase-3β (GSK-3β) phosphorylation. Reactivation of GSK-3β diminished BRD7-elicited Nrf2 activation. In addition, restraining of Nrf2 diminished the BRD7 overexpression-induced beneficial effects on HG-induced podocyte damage. Taken together, these data document that BRD7 defends against HG-induced podocyte damage by enhancing Nrf2 via regulation of GSK-3β. Our work indicates that the BRD7/GSK-3β/Nrf2 axis may play a key role in mediating podocyte injury in diabetic nephropathy.