SFN inhibits cancerous cell growth and induces autophagy inhibition in MDA-MB-231, BT549, and MDA-MB-468 cells. SFN induces autophagy by downregulating HDAC6 expression and increasing acetylation modification and membrane translocation of PTEN. SFN and doxorubicin combination exhibits synergistic inhibition on TNBC cell growth with a greater inhibitory effect on MDA-MB-231 xenograft growth compared to a single treatment. SFN promotes the death of breast cancer cells and prevents their spread to other tissues. This evidence concerns the gene HDAC6 and breast cancer.