Dr. Joseph Schlessinger is one of the pioneers of the field of Signal Transduction, which is integral for cancer treatment, and numerous other fields as well.
Signal transduction refers processes by which a cell alter a type of signal. Most signal transduction processes either include sequences which are ordered of biochemical reactions within the cell. These are then carried out by enzymes, activated by second messengers. The final result is a signal transduction pathway. This usually happens extremely quickly, normally in milliseconds (such as the case of ion flux). Conversely this can take minutes for the activation of lipid-mediated and protein kinase cascades. That being said, some such reactions can take several hours, days and even more. This is determined by necessity of the gene expression completion.
The number of molecules and proteins participating in the scenarios with regards to signal transduction grows as the process emanates from the beginning stimulus, resulting in a “signal cascade,” beginning with a relatively tiny stimulus that causes a greater response. This is referred to as amplification of the signal.
In single-cell organisms as well as bacteria, the variety of process of signal transduction of which the cell is capable of affects the number of ways it can respond to its environment. In more complex organisms, a myriad multitude of various signal transduction processes are necessary for the coordination of the behavior and function of the comprising individual cells. This is both understandable and necessary so the whole organism can properly function. As you could expect, more complex organisms have a larger number of signal transduction processes. Consequentially, getting any sensory input from the outside environment at the cellular level relies on signal transduction.
This is why countless diseases including cancer, diabetes, heart disease and many more are involved with signal transduction and are a result of a flaw of the signal transduction pathways. This work is still far from being finished and additional support are needed for the better of us all.