Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Establishing metastasis

25.09.2018

A protein called vaccinia-related kinase 1 may help cancer establish itself in new areas of the body during metastasis

Sometimes negative results can point researchers in the right direction.


When mammary epithelial cells are grown in a 3D culture matrix, they proliferate and form hollow colonies that mimic the organization of an epithelial tissue. 3D cultures of control cells (left) and cells that over-express VRK1 (right) behave very differently in this context. Although all cells organize into colonies and form cell:cell junction markers (red, cadherin), VRK1 over-expression leads to much more vigorous cell proliferation and the formation of larger colonies. These results may have relevance to the colonization of tissues during cancer metastases. (images taken from Mon, MacKinnon and Traktman, PLoS One)

Credit: Created by Paula Traktman from images appearing in Figure 5C of the September 4, 2018 article by Mon, MacKinnon and Traktman, as allowed by the Creative Commons License (https://creativecommons.org/licenses/by/4.0/)

In results published in PLOS ONE on September 4, 2018, scientists at the Medical University of South Carolina (MUSC) examined a protein called vaccinia-related kinase 1 (VRK1) that they hypothesized was important for metastasis. They found that, rather than causing cancer cells to migrate and invade, VRK1 over-expression had the opposite effect.

Yet this behavior could well help cancer to establish itself in new parts of the body, according to study director and Hirschmann Endowed Professor Paula Traktman, Ph.D., in the MUSC Hollings Cancer Center.

Traktman and graduate student Aye M. Mon started with the idea that high levels of VRK1 might be associated with breast cancer. Other research had suggested this, and Traktman's own work had revealed that depleting VRK1 caused cells to grow more slowly and to cause smaller tumors and fewer metastases in mice. Drawing on these results, Mon and Traktman wanted to see how cells would grow when VRK1 was over-expressed. "The logic was that, if we over-express VRK1, maybe the cells would grow faster and maybe they would be invasive and migratory and contribute to metastasis," said Traktman.

To their surprise, they found that the opposite was true. When they over-expressed VRK1 in mammary epithelial cells growing in tissue culture dishes, those cells did not grow more rapidly than cells with normal levels of VRK1. And, contrary to their hypothesis, the cells tended to migrate and invade much more slowly.

But, when the VRK1 over-expressors were cultured under 3D conditions that mimic tissues, they grew more rapidly and established larger colonies. Intrigued, Mon and Traktman took a closer look at the characteristics of these cells. They examined a hallmark of cancer cells known as epithelial-to-mesenchymal transition, or EMT. Many cells undergo EMT on their way to becoming cancer cells. The transition enables them to migrate away from the tumor.

They observed that the cells with high levels of VRK1 were more apt to form cell-to-cell connections and had lower levels of mesenchymal markers that are often present in cancer cells. Rather, the cells seemed to undergo the opposite transition, from mesenchymal to epithelial. The cells were much less likely to migrate.

These negative results pointed the researchers in a new direction. If high levels of VRK1 caused cancer cells to migrate more slowly, perhaps VRK1 was necessary to enable cells to colonize a new area of the body. In such a process, cancer cells spreading throughout the body would need to abandon the characteristics that make them spread and adopt the traits of cells that would anchor them in place. It is that kind of behavior that allows metastases to begin growing in other parts of the body.

To confirm their new hypothesis, Traktman and Mon teamed up with pathologist A. C. McKinnon at the Medical College of Wisconsin. McKinnon provided the team with cells from breast cancer patients who had metastases to their lymph nodes. They found much higher levels of VRK1 in the lymph node metastases than in the primary tumor cells. In addition, they examined the expression levels of VRK1 in public databases of breast cancer and found that high levels of VRK1 were associated with the most aggressive cancers. Such high levels were also associated with the worst prognoses in patients with metastatic breast cancer.

Traktman summarizes the process. "For a tumor to be aggressive, some of the cells have to break off of the primary tumor and invade through the surface and into the bloodstream and then out of the bloodstream and find a new site," said Traktman. "In order to form a metastasis in a new area, the cells have to stop being wanderers and colonize." And it is possible that VRK1 over-expression enables such cancer cells to colonize new sites in the body.

Traktman and Mon suspect that this finding may extend to other types of cancer, such as brain cancer and liver cancer. In fact, high levels of VRK1 are found in certain types of liver cancer. These results justify the search for small molecules that might inhibit VRK1. Also, VRK1 may one day serve as a biomarker of aggressive cancers, which could thus inform oncologists as they decide on more advanced or conservative courses of treatment.

Traktman and Mon stress the importance of keeping their minds open as they conduct their research. "You can go into research with one model and be completely wrong, and it can actually turn out more interesting than you think," said Traktman. "It's a lesson for letting the data take you down the road to an interesting finding."

###

About MUSC

Founded in 1824 in Charleston, The Medical University of South Carolina is the oldest medical school in the South. Today, MUSC continues the tradition of excellence in education, research, and patient care. MUSC educates and trains more than 3,000 students and residents, and has nearly 13,000 employees, including approximately 1,500 faculty members. As the largest non-federal employer in Charleston, the university and its affiliates have collective annual budgets in excess of $2.2 billion. MUSC operates a 700-bed medical center, which includes a nationally recognized Children's Hospital, the Ashley River Tower (cardiovascular, digestive disease, and surgical oncology), Hollings Cancer Center (a National Cancer Institute-designated center) Level I Trauma Center, and Institute of Psychiatry. For more information on academic programs or clinical services, visit musc.edu. For more information on hospital patient services, visit muschealth.org.

About Hollings Cancer Center

The Hollings Cancer Center at the Medical University of South Carolina is a National Cancer Institute-designated cancer center and the largest academic-based cancer research program in South Carolina. The cancer center comprises more than 100 faculty cancer scientists and 20 academic departments. It has an annual research funding portfolio of more than $40 million and a dedication to reducing the cancer burden in South Carolina. Hollings offers state-of-the-art diagnostic capabilities, therapies and surgical techniques within multidisciplinary clinics that include surgeons, medical oncologists, radiation therapists, radiologists, pathologists, psychologists and other specialists equipped for the full range of cancer care, including more than 200 clinical trials. For more information, visit http://www.hollingscancercenter.org

Media Contact

Heather Woolwine
woolwinh@musc.edu
843-792-7669

 @muschealthpn

http://www.musc.edu 

Heather Woolwine | EurekAlert!
Further information:
http://dx.doi.org/10.1371/journal.pone.0203397

Further reports about: CANCER MUSC Metastasis breast cancer cancer cells epithelial liver cancer metastases

More articles from Health and Medicine:

nachricht Hepatitis: liver failure attributable to compromised blood supply
19.12.2018 | Technische Universität München

nachricht Collagen nanofibrils in mammalian tissues get stronger with exercise
14.12.2018 | University of Illinois College of Engineering

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New megalibrary approach proves useful for the rapid discovery of new materials

Northwestern discovery tool is thousands of times faster than conventional screening methods

Different eras of civilization are defined by the discovery of new materials, as new materials drive new capabilities. And yet, identifying the best material...

Im Focus: Data storage using individual molecules

Researchers from the University of Basel have reported a new method that allows the physical state of just a few atoms or molecules within a network to be controlled. It is based on the spontaneous self-organization of molecules into extensive networks with pores about one nanometer in size. In the journal ‘small’, the physicists reported on their investigations, which could be of particular importance for the development of new storage devices.

Around the world, researchers are attempting to shrink data storage devices to achieve as large a storage capacity in as small a space as possible. In almost...

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Scientists to give artificial intelligence human hearing

19.12.2018 | Information Technology

Newly discovered adolescent star seen undergoing 'growth spurt'

19.12.2018 | Physics and Astronomy

From a plant sugar to toxic hydrogen sulfide

19.12.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>