Prof. Joseph Schlessinger is one of the first investigators of the sub-field of Signal Transduction, which is paramount for cancer treatment, and numerous other fields as well.
Signal transduction refers to any process by which a cell transform one kind of signal. Most signal transduction processes either involve sequences which are ordered of biochemical reactions inside the cell. These are then carried out by enzymes, activated by second messengers. The overall 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 a few hours, days and even more. This is determined by necessity of the gene expression completion.
The amount of molecules and proteins participating in the events with regards to signal transduction grows as the process emanates from the primary stimulus, and the result is a “signal cascade,” beginning with a relatively tiny stimulus that elicits a much greater response. This is referred to as amplification of the signal.
In single cell organisms as well as bacteria, the myriad of process of signal transduction of which the cell is capable of affects the number of ways it can respond to its environment. In multicellular organisms, a variety 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 greater number of signal transduction processes. In addition, getting any stimulus from the outside environment at the cellular level depends 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 defect of the signal transduction pathways. This work is still far from being finished and more financial support are needed for the better of us all.