What is a pathway? Can you give an example of a pathway?

[Music] what are pathways when a cell starts functioning and it it is being instructed to divide or to produce a protein or produce things it oftentimes does it in these pathways not unlike the idea of going from minneapolis to chicago there is a path of roads that you follow to go in that direction and every one of those turns you make you could look at as being an individual gene and a gene product so let's imagine a cell that has a signal out on its surface and a growth hormone comes along and says i'm going to activate this cell to grow and what the cell will do is it will say okay i'm going to activate the ras gene that gene is going to activate other proteins those proteins are going to activate other proteins and then all of those proteins are going to go in the nucleus and instruct the cell to generate all the machinery to divide and grow one gene can't do that it takes lots of products and oftentimes those products are all part of the pathway to get to the end point of producing a protein or producing a function like proliferation or division you can imagine for a cell to grow and divide lots of things have to happen you have to create two daughter cells lots of things have to happen and all of those things happen by a set of pathways that are activated and in myeloma oftentimes there are pathways that are activated what's interesting about that therapeutically is that if i understand the pathway all i have to do is block one step of the pathway and i can block all the downstream events so there may be 10 events that have to happen i don't have to block all 10. i can just block one of them and everything from then on will stop so a lot of the therapeutics now are directed at understanding key driver pathways that if i interfere with that pathway i will stop the cell from dividing there's a potential problem there and that is if i interfere with a pathway in a tumor cell what do i do to interfere with pathways in normal cells and that's where you get the toxic side effects so sometimes the side effects of a therapy is the good news is i'm killing the tumor cell the bad news is i'm starting to kill normal cells too causing some of the toxic side effects so again the research is saying how do i target the critical pathways that will only impact the tumor cell without destroying normal cells and that's part of the research that's going on as well