Our work provide new clues about the role of GSDMB and its isoforms in cancer: a) there is a differential expression of GSDMB isoforms in breast cancer; b) GSDMB-1 and -2 trigger a pro-migratory and pro-invasive program in breast cancer cells; c) silencing of GSDMB reduces the migratory and invasive capacities in HCC1954 breast carcinoma cell line, d) GSDMB-2 plays an active role in tumor growth and metastasis; e) the identification of GSDMB-2 as a new interacting Hsp90 protein. Here, GSDMB is linked to neoplasm.