The Gene Chip: The Future of ... Video Transcript

Participants

, Margaret Shipp MD, Donna Shu

Summary

As with any disease, the accurate diagnosis of Lymphoma is crucial to providing the best, most effective treatment for each individual patient. So while new medications and treatment strategies get a lot of attention, advances in diagnostic technologies are also exciting and important. At the 42nd annual meeting of the American Society of Hematology in December, there was a lot of talk about something called a gene chip -- or DNA microarray analysis -- which has recently been used to diagnose Diffuse Large B-Cell Lymphoma. What is a gene chip and how does it work? How will it lead to more effective treatments? Our panel of experts will include Margaret Shipp, MD, who presented on this topic at the conference.

Webcast Transcript

WAYNE FREEDMAN: Hi, I'm Wayne Freedman. Thanks for joining us on this webcast. Lymphoma's like any other disease in that doctors need an accurate diagnosis to give the best and most effective treatment for each patient. So while we spend a lot of time talking about new medications and new treatments, we don't want to overlook diagnostic advances. They are exciting, and they're important, and they didn't get overlooked here in San Francisco when the American Society of Hematology held its annual meeting.

Among the hot topics, something called DNA microarray analysis, which researchers have developed to diagnose large B cell lymphoma. Microarray analysis. That sounds complicated. So what is it? Well, that's why have guests, thank goodness. Here is Dr. Margaret Shipp. She is an associate professor of medicine at the Dana-Farber Cancer Institute at Harvard University. She directs the lymphoma program there. And we have Donna Shu, the president of the Lymphoma Research Foundation of America. Ladies, thank you for joining us.

Doctor, what is a gene chip?

MARGARET SHIPP, MD: A gene chip is a way of being able to understand the message system of a cell. If you think about the way that a cell knows how it should behave, there is basic genetic information encoded in DNA. DNA is then turned into RNA, and RNA is made into protein, and the protein in a cell is actually what makes a cell do -- it's the instructions -- makes a cell do what it should do. What a gene chip allows you to do is to examine those genetic instructions for many of the different genes in the body with a single approach. So the way that this works is that you make from a type of cell that you're interesting in evaluating RNA, and then you have a platform, which is the chip, and that platform has on it representations -- DNA -- for thousands of genes. This is represented in a size that's probably smaller than a quarter. What you can do is you can take the RNA from a tumor cell and overlay it on this chip that has thousands of genes represented, wash it and scan it with a special camera, and get a computer representation of the expression of those thousands of genes just by looking at the information on that chip.

WAYNE FREEDMAN: What do you mean by expression?

MARGARET SHIPP, MD: Expression is an indication of how much of a specific gene product exists in a certain cell, so you get an idea of how active that gene is in a cell. Is it high? Are the levels high? Are the levels low? So you can begin to put together the genetic information by understanding which genes are expressed at high levels, which genes are expressed at low levels, and understand what types of genes are active in different cell types.

WAYNE FREEDMAN: You always get a different road map depending on the tumor?

MARGARET SHIPP, MD: Yes, almost certainly we do.

WAYNE FREEDMAN: So you look at a cell or you look at a plate, and you see the active cells, and then you can determine --

MARGARET SHIPP, MD: Basically what you do is you examine with a single chip the gene expression from all of the different genes that are represented on that chip, so what you can do is get basically a blueprint of the gene activity in a cell by looking at the pattern on the chip. So then what you need to do is you need to compare it to understand how that's similar or different -- different from other tumors, from normals cells, from other types of cancer.