Breast Cancer, treatment derivatives

Nguyen, A., Marsaud, V., Bouclier, C., Top, S., Vessieres, A., Pigeon, R, Gref, E., Legrand, R, Jaouen, G., and Renoir, J. M. 2008. Nanoparticles loaded with ferrocenyl tamoxifen derivatives for breast cancer treatment. Int. J. Pharmaceut. 347 128-35. 

The answer is d. (Hardman, pp 1275-1276J Tamoxifen is an estrogen antagonist used in the treatment of breast cancer. Postmenopausal women with metastases to soft tissue and whose tumors contain an estrogen receptor are more likely to respond to this agent Little benefit is derived from tamoxifen if the tumor does not have estrogen receptors. 

Tamoxifen, a first-generation SERM, is a nonsteroidal triphenylethylene derivate routinely used in clinical practice for the treatment and prevention of breast cancer in high-risk populations (Robertson 2004). This drug produces an estrogen antagonist effect on the breast and an estrogen agonist effect... 

Goldenberg, M.M., "Trastuzumab, a Recombinant DNA Derived Monoclonal Antibody, a Novel Agent for the Treatment of Metastatic Breast Cancer," Clin. Ther., 21, 309-318 (1999). 

Iressa (ZD 1839) is an orally active tyrosine kinase inhibitor selective for the epidermal growth factor (EGF) receptor tyrosine kinase. Iressa is undergoing clinical trials in the treatment of various solid tumors, including head and neck cancer, breast cancer and non-small cell lung cancer. Its antitumor activity is derived from the fact that the EGF receptor and EGF signaling are... 

It was previously thought that 5-FU inhibits the enzyme by classical competitive inhibition. However, it was found that 5-FU is a transition-state substrate, and it forms a covalent complex with tetrahydrofolate and the enzyme in the same way that the natural substrate does. The reaction, however, will not go to completion, since the fluoro-uridine derived from the antimetabolite remains attached to the enzyme, and the latter becomes irreversibly deactivated. Recovery can occur only through the synthesis of new enzyme. Fluorouracil is used in the treatment of breast cancer and has found limited use in some intestinal carcinomas. Unfortunately, this drug has the side effects usually associated with antimetabolites. Its prodrug, fluorocytosine (8.35, which is also an antifungal agent) is better tolerated. 

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