Expression Profiling in Prognosis

00:00 Now, how do we currently go about treating cancers? It has been up until fairly recently sort of a shot in the dark with our relationship of chemotherapies and surgeries and radiation therapies.

00:20 It would be nice if we could get things to be a little bit more targeted, so specific to the cancer.

00:27 It turns out with the advent of so many great technologies, we really can start to target therapies.

00:35 Expression profiling is one of the means that we can use to discover what the breast cancer is manifesting itself as. You’ll recall earlier in the lecture, I brought up the idea that each of the cells within the tumor itself could be quite heterogeneous or different from each other. Although the first cell may have had the driver mutation, the next cells may have acquired additional mutations.

01:07 So, they’ll often have very distinct profiles. One person’s tumor might have a very distinct profile than another person’s tumor. So with the advent of expression profiling, we can kind of line up, as you can see here on the left and right, different sort of profiles of gene expression. I’m not going to go into the detail of the microarray technique because that’s something again we covered under the biotechnology section of a previous lecture. So, we can see distinctly that there’s a difference in expression. We can use these techniques to decide on a prognosis and develop targeted therapies for that particular, let’s say, brand of cancer. As an example of expression profiling, I’d like to bring up the idea of breast cancers. You’re probably all familiar that there are a multitude of different forms of breast cancer, each of them expressing different expression profiles.

02:16 Different genes are expressed. So, they may or may not express estrogen or progesterone sensitivity or we may see amplification of certain oncogenes. It may or may not have metastasized.

02:30 Now, all of this information is really important when we decide on targeted therapies.

02:36 Now, we don’t need to expose a patient to necessarily all of the treatments that are available to us.

02:43 In summary, this lecture, I provided you a recap of some of the genes that could be involved in cancer development. In short, all of that is about broken cell cycle controls.

02:58 Thank you so much for listening.