IRF1 transcriptionally activates ALOX15B to enhance ferroptosis sensitivity in triple-negative breast cancer

Abstract

This study focused on the transcriptional activation of arachidonate 15-lipoxygenase type B (ALOX15B) by interferon regulatory factor 1 (IRF1) to promote ferroptosis in triple-negative breast cancer (TNBC) cells. In this study, TNBC and adjacent non-cancerous tissues were collected to detect ALOX15B expression. Functional studies were conducted by overexpressing or knocking down ALOX15B in TNBC cells treated with erastin (a ferroptosis inducer). The role of IRF1 as a potential transcriptional regulator of ALOX15B was explored using bioinformatics tools, dual-luciferase reporter gene assays, electrophoretic mobility shift assays (EMSA), and chromatin immunoprecipitation (ChIP) followed by quantitative polymerase chain reaction (qPCR). Our results revealed that ALOX15B expression was significantly lower in TNBC tissues compared to adjacent non-cancerous tissues. Functionally, ALOX15B overexpression inhibited ferroptosis-related proteins SLC7A11 and GPX4, decreased cell viability and glutathione levels, and increased malondialdehyde levels, reactive oxygen species levels, and lipid oxidation. Conversely, knocking down ALOX15B had the opposite effect. Bioinformatics analysis predicted IRF1 as a potential transcriptional regulator of ALOX15B, which was confirmed using dual-luciferase reporter gene assays, EMSA, and ChIP-qPCR. IRF1 overexpression increased ALOX15B expression and promoted ferroptosis in TNBC cells, while IRF1 knockdown had the opposite effect. Importantly, knocking down IRF1 and overexpressing ALOX15B simultaneously demonstrated that IRF1 enhanced TNBC cell ferroptosis sensitivity by promoting ALOX15B expression. Collectively, our study suggests that IRF1 transcriptionally activates ALOX15B to enhance ferroptosis sensitivity in TNBC cells. These findings provide new insights into the molecular mechanisms underlying TNBC progression and suggest potential therapeutic targets for TNBC treatment.