Featured Research

from universities, journals, and other organizations

Cancer: Antibodies can directly target oncoproteins inside cancer cells to suppress aggressive cancer growth

Date:
September 8, 2011
Source:
Agency for Science, Technology and Research (A*STAR), Singapore
Summary:
Scientists have made a landmark discovery in the battle against the rapid spread of aggressive cancers. Contrary to the current theory that antibodies can only bind to cancer proteins found on the cancer cell surface, scientists have now discovered that antibodies can in fact directly target oncoproteins that reside within the cancer cells to suppress aggressive cancer growth.

Scientists at A*STAR's Institute of Molecular and Cell Biology (IMCB) have made a landmark discovery in the battle against the rapid spread of aggressive cancers associated with PRL-3 oncoprotein[1]. Contrary to the current accepted theory that antibodies can only bind to cancer proteins found on the cancer cell surface, the IMCB team led by Dr Zeng Qi is the first to discover that antibodies can in fact directly target intracellular oncoproteins like PRL-3 that reside within the cancer cells to suppress cancer growth successfully. This breakthrough finding will pave the way for more targeted solutions for cancer treatment and also offers hope for cancer prevention.

Related Articles


The leading cause of death by cancer is cancer metastasis -- the rapid and often fatal spread of cancer cells from the primary tumour to other parts of the body. PRL-3, which stands for "Phosphatase of Regenerating Liver 3," is a key protein linked to cancer metastasis. PRL-3 is commonly overproduced in many types of aggressive lung, liver, kidney, bone and breast cancer. For example, colorectal cancer and breast cancer, the top five most deadly cancers in the world[2] and also the number one most common cancers in both male and female population respectively in Singapore[3], are frequently associated with elevated levels of PRL-3 phosphatase. PRL-3 is therefore an ideal target for cancer diagnostics and treatment.

Traditionally, oncoproteins like PRL-3 phosphatase which reside within the cancer cells were thought to be inaccessible by antibodies because it is widely accepted that antibodies are too big to cross the cell membrane. This study suggests that cancers could be effectively treated through the direct introduction of antibodies to target the PRL-3 oncoprotein inside the cancer cell. Likewise, vaccination with PRL-3 antigen to prevent cancer can be administered to induce the body's immune system to produce PRL-3 antibodies that will directly target the PRL-3 oncoprotein within the cancer cell.

Said Dr Zeng, who first identified PRL-3 phosphatase in 1998, "We are very excited because this study showed for the first time that it is possible to successfully suppress cancer growth by direct targeting of intracellular oncoproteins, such as PRL-3, with the respective cancer-specific antibodies." Using mouse models in this study, by directly introducing PRL-3 antibodies into the mice, the scientists observed a 70% to 90% reduction of tumours caused by PRL-3 expressing cancer cells. This significant reduction is also achieved by vaccinating the mice with PRL-3 antigen[4] to produce antibodies that could specifically target PRL-3-expressing cancer cells.

To demonstrate that antibodies can indeed directly target other intracellular oncoproteins as a general phenomenon, the team also performed the experiment with two different representative intracellular proteins, EGFP[5] and mT[6]oncoprotein. It was observed that the antibodies introduced to the mice could directly target the intracellular oncoproteins to dramatically retard tumour progression.

Added Dr Zeng, "This means that a whole new list of intracellular oncoproteins previously thought to be untargetable by therapeutic antibodies or vaccinations can now be potentially targeted. This will expand the scope for tailor-made antibody therapy as well as usher in a new era of tailor-made cancer vaccines."

Professor Sir David Lane, Chief Scientist of A*STAR said, "Dr Zeng's breakthrough discovery is a fine example of how years of basic research lay the foundation for advancement in translational medicine. This study has introduced a potential paradigm shift in the ways we target cancer cells with antibodies and vaccines. It has opened unexpected doors of possibilities in cancer and immunology research. Much further work will of course be needed to establish the safety and efficacy of this approach in cancer patients but it indeed paves the way for more targeted cancer treatment & offers new hope for cancer prevention."

Said Dr Zeng, "Cancer affects people regardless of age, gender, wealth or social status. It represents a tremendous burden on patients, their families and the society. Existing antibody therapy for cancer treatment is very costly. I hope that our research will pave the way for cancer vaccination to become a mainstream cancer treatment that is both effective and affordable for the cancer patients. Especially for individuals who are genetically pre-disposed to specific types of cancer, tailor-made vaccination may one day be able to prevent cancer before it strikes."

Notes:

[1] Oncoprotein is the product of an oncogene, which is a gene that has the potential to cause cancer.

[2] Globocan 2008, The International Agency for Research on Cancer (IARC) in 2010.

[3] Singapore Cancer Registry, "Trends in Cancer Incidence in Singapore 2005-2009"

[4] Antigens are foreign substances, usually proteins or polysaccharides, which stimulate the immune system to produce specific antibodies. The antibodies inactivate the antigens and help to remove them from the body.

[5] EGFP (Enhanced Green Fluorescent Protein) is a general reporter protein which localizes inside the cell. Because it is not expressed in host tissues, it serves as an artificial 'cancer-specific' intracellular oncoprotein.

[6] mT (polyomavirus middle T) oncoprotein is frequently used in animal breast cancer model system to mimic the development of spontaneous breast cancer. Polyomaviruses have been extensively studied as tumour viruses in humans and animals, leading to fundamental insights into cancer formation.


Story Source:

The above story is based on materials provided by Agency for Science, Technology and Research (A*STAR), Singapore. Note: Materials may be edited for content and length.


Journal Reference:

  1. K. Guo, J. Li, J. P. Tang, C. P. B. Tan, C. W. Hong, A. Q. O. Al-Aidaroos, L. Varghese, C. Huang, Q. Zeng. Targeting Intracellular Oncoproteins with Antibody Therapy or Vaccination. Science Translational Medicine, 2011; 3 (99): 99ra85 DOI: 10.1126/scitranslmed.3002296

Cite This Page:

Agency for Science, Technology and Research (A*STAR), Singapore. "Cancer: Antibodies can directly target oncoproteins inside cancer cells to suppress aggressive cancer growth." ScienceDaily. ScienceDaily, 8 September 2011. <www.sciencedaily.com/releases/2011/09/110908104205.htm>.
Agency for Science, Technology and Research (A*STAR), Singapore. (2011, September 8). Cancer: Antibodies can directly target oncoproteins inside cancer cells to suppress aggressive cancer growth. ScienceDaily. Retrieved November 28, 2014 from www.sciencedaily.com/releases/2011/09/110908104205.htm
Agency for Science, Technology and Research (A*STAR), Singapore. "Cancer: Antibodies can directly target oncoproteins inside cancer cells to suppress aggressive cancer growth." ScienceDaily. www.sciencedaily.com/releases/2011/09/110908104205.htm (accessed November 28, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, November 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Rural India's Low-Cost Sanitary Pad Revolution

Rural India's Low-Cost Sanitary Pad Revolution

AFP (Nov. 28, 2014) — One man hopes his invention -– a machine that produces cheap sanitary pads –- will help empower Indian women. Duration: 01:51 Video provided by AFP
Powered by NewsLook.com
Research on Bats Could Help Develop Drugs Against Ebola

Research on Bats Could Help Develop Drugs Against Ebola

AFP (Nov. 28, 2014) — In Africa's only biosafety level 4 laboratory, scientists have been carrying out experiments on bats to understand how virus like Ebola are being transmitted, and how some of them resist to it. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
Ebola Leaves Orphans Alone in Sierra Leone

Ebola Leaves Orphans Alone in Sierra Leone

AFP (Nov. 27, 2014) — The Ebola epidemic sweeping Sierra Leone is having a profound effect on the country's children, many of whom have been left without any family members to support them. Duration: 01:02 Video provided by AFP
Powered by NewsLook.com
Experimental Ebola Vaccine Shows Promise In Human Trial

Experimental Ebola Vaccine Shows Promise In Human Trial

Newsy (Nov. 27, 2014) — A recent test of a prototype Ebola vaccine generated an immune response to the disease in subjects. Video provided by Newsy
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:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

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