Let's say I had a network of enzymes that are all interconnected that may be involved in cancer progression. Each enzyme produces a chemical product that might be used by some other member in this network, but each enzyme might produce a product at different rates. Is there a way I could possibly use graph theory to model this network, along with the rate traffic through this enzyme network, in order to make some predictions on the final "product" of this network (the final product of which assists in cancer)? I've had some graph theory before, but is there some way to incorporate the "rate of traffic" parameter into such a graph? So not just figuring the number of possible ways it might be possible to synthesize a final product, but how much and how fast we expect it to happen? What are some topics I can look up to point me in the right direction with regards to graph theory?