A search in clinicaltrial.gov with breast cancer and HDAC inhibitor showed 45 such trials including the same categories mentioned above.Targeted therapies against histone methylation: Till date, clinical trials on breast cancer using targeted histone methylation therapy has not yet been reported as per our knowledge but quite a significant number of trials are either ongoing or completed in leukemia, lymphoma, endometrial cancer, prostrate cancer, melanoma among others. This evidence concerns the gene HDAC9 and breast carcinoma.