Question

why would aromsin compete with testostreone the precursor of estrogen.

Answer 1

Estrogen and progesterone, both are steroid hormones by nature. Structurally, these hoemones are synthesized from cholestrol as the main precursor which is sequentially converted to give rise to dehydroepiandrosterone or DHEA which in turn results in the formation of estrogen and progesterone. Thus, this states that the primary precursor for both these steroid hormones remains same.

The structural and functional similarities among these two hormones have suggested that a common inhibitor (for initial or final stages of bio-synthesis) would function to eliminate the physiological relevance of these hormones. This is why aromasin or different types of aromatase inhibitors are generally used to delinate or halt the biological function of these hormones. Such therapeutic effects are generally utilized in anti-cancer therapies such as cervical cancer, ovarian cancer, breast cancer, prostate cancer etc.