Screening Possible Substrates of E3 Ligase RNF19A by Immunofluorescence Staining

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer and one of the most common and deadly cancers in women. The incidence of TNBC is high globally, but there are few treatment options, and chemotherapy remains the primary treatment method for TNBC patients. Research found that ubiquitination is a potential target that can help provide better treatment to multiple cancers including TNBC. However the role of ubiquitinationin cancer is not very clear. Thus, more in-depth research is needed to create better treatment for TNBC patients. An bioinformatics analysis was conducted to identify potential substrates for the E3 ligase RNF19A. Immunofluorescence staining was utilized to compare the co-localization of RNF19A with these potential substrates in A549 and MDA-MB-231 cell lines. Then TP53 activator PRIMA-1 and the SOD1 inhibitor ATN-224 to was added to observe the fluorescence intensity of RNF19A. The findings revealed the RNF19A can affect the fluorescence intensity of subcellular localization of TP53 in MDA-MB-231 cells. The differential effects were also noted in A549cells. In contrast, treatment with the SOD1 inhibitor resulted in decreased fluorescence in A549 cells, indicating a specific pathway involvement in non-small cell lung cancer (NSCLC) rather than TNBC. This study demonstrates that fluorescence intensity of RNF19A is impacted by the addition of the activator and the inhibitor of TP53. The RNF19A can potentially contribute to the understanding of its function in cancer-related cellular processes. These findings provide a foundational basis for exploring RNF19A as a potential therapeutic target in conditions like TNBC, marked by aberrant protein localization and function