Dr. ERIC WEINER (Dana Farber Cancer Institute): And I think it really speaks to the underlying nature and behavior of hormone receptor positive breast cancer.

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Sometimes it is a normal gene that directs the production of a hormone, such as insulin, or of the cell machinery which that hormone stimulates, such as the insulin receptor.

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The issues relate to an oestrogen receptor test, which detects whether patients would benefit from hormone treatment.

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First, by using radioactive tracers to track the behavior of hormones, Lekfowitz was able to identify and extract unique receptor molecules protein assemblies on the surface of cells including the receptor for the well-known fight-or-flight hormone, adrenaline.

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