This blog entry is a response to an article in the New York Times, “How Bright Promise in Cancer Treatment Fell Apart”, published July 8th. The original article can be read through the link in the text below.
To truly identify a personalized treatment for a cancer patient, we need to understand not just the biology of the tumor itself, but also the host environment in which the tumor grows. This includes not only the tumor’s blood supply, but also the individual’s immune system. The details of how blood is supplied to the tumor (angiogenesis) are now much better understood, and several drugs are currently available that help reduce the blood supply to the tumor (ie., Avastin). But the science behind the immune system and its role in tumor growth is much less understood. Without understanding the variation in our immune systems (both the initial state and changes that it undergoes as the tumor takes its course), we can poke holes all we want at the tumor itself, but the tumor will likely outsmart the target without “treating” or taking into consideration the host’s individual immune response.
A recent NY Times article calls into question the value of genomic profiling, but most of the supporting evidence was really challenging the integrity of the data reporting. Genomic profiling will be hard to ignore in the future, and we can work to fix the issues pertaining to data generation. There is no question that genetic data will be increasingly important, and there are many examples of cancer drugs that have hit the right target and been wildly successful (Gleevec being the first). But even with Gleevec, some patients still relapse, either because they build resistance to the drug or because their tumor finds a way to mutate. In either case, it’s not sufficient to profile only the tumor itself. We also need to better understand and/or alter the immune system in order to undercover ways to maintain the response. We need tools like Adaptive’s next generation high-throughput immune sequencing assays to unveil the intricacies of each person’s immune system and ultimately help bring novel “targeted” immunomodulators to market.