BREAST CANCER BASE

One, on the progress of endocrine therapy

1, estrogen receptors (estrogen recepter ER)

Molecular biology of gene theory that the steroid hormone (estrogen) can induce a large number of nucleic acid biosynthesis and related enzymes and protein expression, which stimulate gene transcription strictly dependent on receptor and ligand combination. ER as a trans-acting factor, with the estrogen response elements (estrogen responsive elements, ERE) combine to stimulate transcription. The gene expression, the transcription initiation is the key, and the transcription initiation site is the promoter, it is DNA and RNA polymerase of specific binding sites. Promoter activity determines the speed of transcription process. ERE which have greatly enhanced the activity of the promoter role. Thus, estrogen-response system ER in breast cancer occurrence and development plays an important role in estrogen directly to the ER with breast cancer cells, cancer cells regulate the expression of genes and phenotypic characteristics. ER and as trans-acting factor and at the genome or both sides of the specific cis-acting elements interact to regulate cancer cell gene transcription translation.

Aromatase inhibitors (ve class — AI) is the study of endocrine therapy for breast cancer the most active part. With the third generation of AI research and development and in-depth applications, tamoxifen (TAM) in the treatment of breast cancer endocrine status of the standards being challenged, Femara (letrozole) in the most clinical research system, the conclusion most certainly against recurrence of the metastases second-line treatment of the rescue good results in ammonia Mian-guided energy (AR/BC2 pilot) and megestrol acetate (AR/BC3 test); femara frontline rescue therapy (025 tests) and preoperative new secondary treatment (024 tests), they are significantly better than TAM; Although TAM compared with the postoperative adjuvant treatment, a million people the largest group of international clinical trials (MA17 NCIC CTG and BIG1-98 pilot) also ongoing, but is expected to get better results.