GSE183008
Regulation of P53 signaling in breast cancer by the E3 ubiquitin ligase RNF187
The tumor suppressor P53 plays critical roles in prohibiting cancer. P53 is rarely mutated and still functional in luminal types of breast cancer. According to current knowledge, wild type P53 function is tightly controlled by post-translational modification, such as ubiquitination. Several ubiquitin ligases were shown to regulate P53 ubiquitination and protein stability. Here, we report RNF187, a RING family ubiquitin ligase, facilitates breast cancer growth and inhibits apoptosis via modulating P53 signaling. RNF187 is elevated in breast cancer and correlates with breast cancer survival only in P53 wild type groups. The bio-informatics analysis shows that RNF187 negatively correlates P53 target gene expression, such as IGFBP3 and FAS in breast cancer. RNF187 depletion inhibits breast cancer growth and facilitates cell death. RNA sequencing analysis indicates that RNF187 could be an important modifier for P53 signaling. Further experiments show that RNF187 interacts with P53 and promotes P53 degradation via facilitating P53 poly-ubiquitination in breast cancer cells. Interesting, the in vitro ubiquitin assay shows that RNF187 could directly ubiquitinate P53, which is independent of MDM2. These finding reveals a novel direct P53 regulator and a potential therapeutic target for breast cancer. Overall design: Breast cancer cell mRNA samples were summarized in six samples, divided into two groups, siControl and siRNF187