An elaborate circuitry of biochemical
reactions mediates the proliferation and differentiation of
We have gained access to this
circuitry through the study of genes implicated in the genesis
of human cancer, "proto-oncogenes", which suffer
genetic damage in cancer cells leading to an unwanted gain
Proto-oncogenes serve as accelerators leading the cell into
relentless cell division. Many of the proteins encoded by
proto-oncogenes serve as relays in the biochemical pathways
that transmit signals from the surface of the cell to the
nucleus. Several of the genes encode protein kinases that
phosphorylate proteins on tyrosine residues.
The understanding of how these molecules participate in various
signal transduction pathways to control such biological processes
as cellular proliferation and differentiation are essential
for us to fully understand the biochemical maladies of cancer.