Although its role in epithelium-originated cancer and its potential as a diagnostic biomarker has been reported in non-small cell lung cancer patients [57], the present study is the first to report that integrin α11 may be a prognostic biomarker for drug-resistant breast cancer patients and an excellent therapeutic target for them, showing the results of cancer patient TCGA dataset analysis and ITGA11 siRNA therapy in animal models of drug-resistant breast cancer. The gene discussed is ITGA11; the disease is breast cancer.