Question

From a strictly mechanistic point of view (i.e., ignoring practicalities, FDA approval, etc), what drugs might be most appropriate for a breast cancer patient with the following known mutations? Explain with signaling diagrams.

(e) ERBB2

(f) PTEN

Answer 1

Singling involved both of the molecules are shown below in attached image

ERBB2 is a tyrosine kinase receptor, it binds to growths factors and stimulate the pathway which supports cell growth and prevent all the signals which cause cell cycle stop or apoptosis.

Whole pTEN is a tumor supressor protein, this cause conversion of PIP3 in to PIP2 thus prevent AKT pathway.  

If we want to block one pathway, among the pathway. It is better to target ERBB2 pathway. So it will prevent a the down stream pathway. And help in preventing abnormal cell growth.

So its better to use blocking antibody against ERBB2 receptor which prevent binding if the growth factor and prevent downstream signaling.