Featured Research

from universities, journals, and other organizations

Shape-altering Genes Linked To Ovarian Cancer

Date:
April 16, 2005
Source:
University Of Texas M. D. Anderson Cancer Center
Summary:
Frequently referred to as a silent killer, ovarian cancer offers few clues to its presence, often until it has spread beyond the ovary to other tissues. Early detection has been difficult because ovarian cancer is not a single disease, but appears in many forms, with each form behaving differently.

"Our finding explains how each of the three major forms of ovarian cancer acquire their unique appearance," says Naora. "These genes cause a metamorphosis of the ovarian epithelial cells, directing them to change their shape."

These strange shapes make each form of ovarian cancer different from one another, and also different to the surface epithelium or outer covering of the ovary from which these cancers are thought to arise, explained Naora. Serous ovarian cancer exhibits features resembling those of the fallopian tubes; the endometrioid form has features resembling the lining of the uterus; mucinous ovarian cancer even looks like intestinal cells.

These mysterious shapes have caused some researchers to speculate that ovarian cancers might originate from some other tissues, and not the ovarian surface epithelium at all. Naora reasoned that ovarian tissue might be coaxed into the different forms by changes in its genetic programming.

Naora suspected that HOX genes, which direct immature embryonic tissue to form the various body structures during development, could become reactivated in ovarian cancer cells. She and her colleagues tested the effect of four HOX genes on cells derived from the ovarian surface epithelium and found that activating different HOX genes caused the cells to change into different shapes and resemble the forms seen in ovarian cancer.

For example, turning on HOXA9 caused cells to form tumors that resembled high-grade serous ovarian cancer. On the other hand, HOXA10 activation resulted in tumors that resembled endometrioid ovarian cancer and HOXA11 caused cells to form tumors that resembled mucinous ovarian cancer. What's more, the research team found that activation of HOXA7 in combination with any of the other HOX genes resulted in formation of low-grade tumors that are less aggressive than high-grade tumors.

Because HOX genes are sensitive to levels of the female hormones estrogen and progesterone produced in the reproductive organs, Naora speculates that abnormal changes in levels of these hormones could explain how the HOX genes come to be turned on in ovarian tissue. Indeed, most of the known risk factors for ovarian cancer are related to levels of these same hormones.

"One of the major problems with diagnosis and treatment of ovarian cancer is that it is not a single disease," Naora says. "Each form of ovarian cancer has its own unique clinical behavior. If we understand what causes these different forms, we have taken the first step toward early diagnosis and therapy tailored to each of the various subtypes."

The American Cancer Society estimates that about 22,220 new cases of ovarian cancer will be diagnosed in the United States during 2005. A woman's risk of getting ovarian cancer during her lifetime is about 1 in 58, accounting for about 3 percent of all cancers in women.

The ultimate goal of Naora's research is to develop a molecular profile or pattern that could be used to determine who is at greatest risk of ovarian cancer and to tailor treatment for women who do develop ovarian cancer.

"An impediment to improving early detection of ovarian cancer is the lack of well-defined pre-malignant or precursor lesions. Furthermore, right now we don't have any way to assess the relative risk for women with a strong family history of ovarian cancer," she continues. "Often these women have their ovaries removed, and unusual changes in the cell shape are seen in many cases. But we don't know if changes in cell shape necessarily lead to cancer. We would like to be able to offer a test that could assess risk and allow women to make more informed choices."

In addition to Dr. Naora, Ph.D., Wenjun Cheng, M.D., Jinsong Liu, M.D., Ph.D, Hiroyuki Yoshida, M.D., Ph.D., and Daniel Rosen, M.D., all of M. D. Anderson, contributed to the research. The research was supported by grants from the National Institutes of Health, the U. S. Army, and the American Cancer Society; an M. D. Anderson Cancer Center Institutional Research Grant; and an award from Cancer Fighters of Houston.


Story Source:

The above story is based on materials provided by University Of Texas M. D. Anderson Cancer Center. Note: Materials may be edited for content and length.


Cite This Page:

University Of Texas M. D. Anderson Cancer Center. "Shape-altering Genes Linked To Ovarian Cancer." ScienceDaily. ScienceDaily, 16 April 2005. <www.sciencedaily.com/releases/2005/04/050415204703.htm>.
University Of Texas M. D. Anderson Cancer Center. (2005, April 16). Shape-altering Genes Linked To Ovarian Cancer. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2005/04/050415204703.htm
University Of Texas M. D. Anderson Cancer Center. "Shape-altering Genes Linked To Ovarian Cancer." ScienceDaily. www.sciencedaily.com/releases/2005/04/050415204703.htm (accessed July 22, 2014).

Share This




More Health & Medicine News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

TheStreet (July 21, 2014) New research shows Gilead Science's drug Sovaldi helps in curing hepatitis C in those who suffer from HIV. In a medical study, the combination of Gilead's Hep C drug with anti-viral drug Ribavirin cured 76% of HIV-positive patients suffering from the most common hepatitis C strain. Hepatitis C and related complications have been a top cause of death in HIV-positive patients. Typical medication used to treat the disease, including interferon proteins, tended to react badly with HIV drugs. However, Sovaldi's %1,000-a-pill price tag could limit the number of patients able to access the treatment. TheStreet's Keris Lahiff reports from New York. Video provided by TheStreet
Powered by NewsLook.com
$23.6 Billion Awarded To Widow In Smoking Lawsuit

$23.6 Billion Awarded To Widow In Smoking Lawsuit

Newsy (July 20, 2014) Cynthia Robinson claims R.J. Reynolds Tobacco Company hid the health and addiction risks of its products, leading to the death of her husband in 1996. Video provided by Newsy
Powered by NewsLook.com
Tooth Plaque Provides Insight Into Diets Of Ancient People

Tooth Plaque Provides Insight Into Diets Of Ancient People

Newsy (July 19, 2014) Research on plaque from ancient teeth shows that our prehistoric ancestor's had a detailed understanding of plants long before developing agriculture. Video provided by Newsy
Powered by NewsLook.com
Contaminated Water Kills 3 Babies in South African Town

Contaminated Water Kills 3 Babies in South African Town

AFP (July 18, 2014) Contaminated water in South Africa's northwestern town of Bloemhof kills three babies and hospitalises over 500 people. The incident highlights growing fears over water safety in South Africa. Duration: 02:22 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