ISL1 is upregulated in breast cancer and promotes cell proliferation, invasion, and angiogenesis.

ISL1 plays a key role in several cancers, including pheochromocytoma, gastrointestinal, pancreatic, and lung tumors and bile duct carcinoma. In order to elucidate the role of ISL1 in breast cancer, we performed quantitative real-time polymerase chain reaction and Western blotting analysis, and we found that ISL1 was upregulated in breast cancer cells and tissues. Moreover, high expression of ISL1 was correlated with tumor size, metastasis, and poor prognosis. Colony formation analysis and CCK-8 analysis revealed that ISL1 facilitated breast cancer cell proliferation. In addition, wound healing analysis and transwell invasion analysis demonstrated that ISL1 played a role in cell migration and invasion. Interestingly, the expression of ISL1 was also associated with the expression of vascular endothelial growth factor (VEGF) in breast cancer, and ISL1 promoted angiogenesis in breast cancer. In conclusion, reducing the expression of ISL1 suppresses proliferation, migration, invasion, and angiogenesis in breast cancer, suggesting that ISL1 might serve as a novel molecular therapy target in breast cancer.