To the best of our knowledge, it is the first report that CAF-secreted Activin A has the ability to reduce the sensitivity of cancer cells to ixazomib; the presence of FST reversed this phenomenon, suggesting that targeting Activin A secreted by CAFs is a therapeutic target with which to overcome ixazomib resistance in MCF7 cells, or that ixazomib may be used to treat breast cancer patients with low expression levels of INHBA in CAFs. The gene discussed is INHBA; the disease is breast cancer.