Our results systematically present the regulation of steroid-converting enzymes and their roles in modulating the intratumoral steroid-hormone levels in BC with a vivid 3D-schema, supporting novel therapy targeting the reductive 17β-HSD7 and proposing a new combined therapy targeting 11β-HSD2 and 17β-HSD7.
These results strongly support that the inhibition of 17β-HSD7 constitutes the basis of breast cancer cell proliferation decreasing that led to the shrinkage of xenograft ER + breast tumor mice model.
Our data showed 17β-HSD7 is amplified in primary and progressive breast cancer, inhibition of 17β-HSD7 in MCF-7 cells modulated 104 proteins primarily involved in cell death/survival, cell growth and DNA processing.
We also demonstrated the central role of 17β-HSD7 in sex-hormone conversion and regulation, supporting it as a novel target for estrogen-dependent (ER+) BC.
In conclusion, genetic variants of 17β-HSD2 and 17β-HSD7 may affect intra-tumour gene expression as well as breast cancer E2 levels in postmenopausal women.
To verify the relevance of 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) activity in controlling breast-cancer cell growth, we have evaluated the correlation of 11beta-HSD2 expression and antiproliferative effects of glucocorticosteroids (GCs) on breast cancer cell proliferation.