Featured Research

from universities, journals, and other organizations

Gene Expression Profiling Not Quite Perfected In Predicting Lung Cancer Prognosis

Date:
November 21, 2006
Source:
Mayo Clinic
Summary:
While there have been significant advances in the use of gene expression profiling to assess a cancer prognosis, a Mayo Clinic review and analysis of existing lung cancer studies shows that this technology has not yet surpassed the accuracy of conventional methods used to assess survival in lung cancer patients.

While there have been significant advances in the use of gene expression profiling to assess a cancer prognosis, a Mayo Clinic review and analysis of existing lung cancer studies shows that this technology has not yet surpassed the accuracy of conventional methods used to assess survival in lung cancer patients.

The interest in and the knowledge of gene expression profiling in medical science has exploded since the completion of the human genome project in 2003. Researchers caution that the science of gene expression profiling, in which scientists examine the genetic signature of a cell, is in its infancy, particularly in lung cancer.

"Growing evidence suggests that gene-based prediction is not stable and little is known about the prediction power of a gene expression profile as compared to well-known clinical and pathologic predictors," according to Ping Yang, M.D., Ph.D., the corresponding author of the study that appears in the November issue of Cancer Epidemiology, Biomarkers and Prevention (CEBP). The study's first author is Zhifu Sun, M.D., a research associate with the Department of Health Sciences Research at Mayo Clinic.

Dr. Yang, a researcher with Mayo Clinic's Department of Health Sciences, said that while gene expression profiling has been successfully used to classify various tumors and assess tumor stage, metastasis and patient survival rates, the evidence suggests that gene-based prediction for lung cancer is not yet entirely dependable. However, some results have been promising: gene profiling has reliably predicted patient survival for lung adenocarcinoma almost as well as established predictors.

The results of conventional methods that factor in age, gender, stage, cell type and tumor grade outweigh the predictive advantage of a gene expression profile. "Any new technique that does not significantly outperform less expensive and easily conducted approaches is less likely to be useful in clinical practice," the authors wrote.

Few studies have compared conventional methods of lung cancer prediction with gene profiling. It remains to be seen whether gene expression profiling of lung cancer cases can replace or augment the existing assessment tools and, furthermore, whether it can lead to improved patient care.

In terms of problems associated with gene expression profiling in lung cancer research, the authors found:

  • The accuracy of gene expression-based outcome prediction varies greatly among studies.
  • Most studies lacked independent validation.
  • Clinical outcome prediction between gene expression profiles and pathological features overlap significantly.

Current analytical algorithms favor genes at high expression or genes highly differentially expressed, most of which are related to tumor differentiation and may not correlate with clinical outcomes; conversely, genes expressed at low levels or in a subtle difference are often overlooked, which may be quite relevant biologically to clinical questions.

The authors of the study recommend that medical scientists engaged in gene expression profiling should:

  • Clearly define a study aim. The main focus in microarray studies should explore the molecular explanations for varied clinical outcomes given a group of patients with similar clinical and pathological characteristics.
  • Lay out and compare alternative study designs
  • Carefully select samples in terms of size, quality and unambiguous clinical outcomes
  • Understand the limitations of DNA microarray
  • Provide clinically relevant interpretation from the study results and address the value added in practice

The study was funded by the National Institutes of Health, National Cancer Institute and Mayo Clinic.


Story Source:

The above story is based on materials provided by Mayo Clinic. Note: Materials may be edited for content and length.


Cite This Page:

Mayo Clinic. "Gene Expression Profiling Not Quite Perfected In Predicting Lung Cancer Prognosis." ScienceDaily. ScienceDaily, 21 November 2006. <www.sciencedaily.com/releases/2006/11/061117121740.htm>.
Mayo Clinic. (2006, November 21). Gene Expression Profiling Not Quite Perfected In Predicting Lung Cancer Prognosis. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2006/11/061117121740.htm
Mayo Clinic. "Gene Expression Profiling Not Quite Perfected In Predicting Lung Cancer Prognosis." ScienceDaily. www.sciencedaily.com/releases/2006/11/061117121740.htm (accessed September 1, 2014).

Share This




More Health & Medicine News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Get on Your Bike! London Cycling Popularity Soars Despite Danger

Get on Your Bike! London Cycling Popularity Soars Despite Danger

AFP (Sep. 1, 2014) Wedged between buses, lorries and cars, cycling in London isn't for the faint hearted. Nevertheless the number of people choosing to bike in the British capital has doubled over the past 15 years. Duration: 02:27 Video provided by AFP
Powered by NewsLook.com
Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Liberia Continues Fight Against Ebola

Liberia Continues Fight Against Ebola

AFP (Aug. 30, 2014) Authorities in Liberia try to stem the spread of the Ebola epidemic by raising awareness and setting up sanitation units for people to wash their hands. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins