Navigation Links
Engineered virus targets and kills apparent cancer stem cells in neuroblastoma
Date:1/20/2009

CINCINNATI After identifying an apparent population of cancer stem cells for neuroblastoma, researchers successfully used a reprogrammed herpes virus to block tumor formation in mice by targeting and killing the cells.

Published online Jan. 21 by PLoS (Public Library of Science) One, the study led by Cincinnati Children's Hospital Medical Center adds to a growing body of evidence suggesting early stage cancer precursor cells with stem-cell-like properties may explain how some cancers form, are treatment resistant and prone to relapse. The study also underscores the increasing potential of targeted biological therapies to help people with stubborn cancers like neuroblastoma, which often recur and metastasize, said Timothy Cripe, M.D., Ph.D., senior investigator and a physician/researcher in the division of Hematology/Oncology at Cincinnati Children's.

"The main finding of our study is that pediatric neuroblastomas seem to have a population of cells with stem-cell characteristics that we may need to target for therapy," Dr. Cripe said. "We also show that one promising approach for targeted treatment is biological therapy, such as an engineered oncolytic virus that seeks out and kills progenitor cells that could be the seeds of cancers."

Neuroblastoma's solid tumors usually attack the sympathetic nervous system, part of the body's autopilot mechanism that controls vital organ function and instinctive responses, like "fight or flight." The disease can be thrown into remission by chemotherapy, radiation or surgery, but it's also known for treatment resistance and a high rate of relapse and death. In patients with high-risk forms of the disease, long-term survival rates are less than 50 percent. The reasons for neuroblastoma's tendency to relapse and spread still need to be proven, said Dr. Cripe, also professor of Pediatrics at the University of Cincinnati College of Medicine.

To further explore the cancer stem cell theory, the research team took human neuroblastoma cells and grew them in laboratory cultures. The cultures contained cells exhibiting biological properties of neural stem cells which are specific to the nervous system and grow to form a variety of nerve tissue. The cultures generated cell colonies that acted like stem cells in the way they divided, grew and were capable of diverse, or multi-lineage, differentiation. Analysis showed the cells also carried known biological markers for nerve stem cells, such as the proteins CD133 and nestin.

The cells advanced into tumor-like cell spheres and were tumorigenic, meaning they had the potential to form tumors. Cells derived from these tumorspheres were relatively resistant to the chemotherapy agent doxorubicin, similar to that seen with some treatment-resistant neuroblastomas. Researchers also noted cells from the tumorspheres carried a gene (MYCN) that is found at amplified levels in aggressive forms of neuroblastoma.

Because neural stem cells and neuroblastoma cells both carry the protein nestin, Dr. Cripe and his colleagues tested the effect of an oncolytic herpes simplex virus called rQNestin34.5 on cells. Developed by cancer researchers Ohio State University, rQNestin34.5 carries a molecular promoter for nestin, which causes it to seek out the protein and cancerous, or precancerous, cells where nestin resides. The virus is genetically programmed to grow inside and be toxic to cancer cells, while leaving healthy tissues alone.

The tumorigenic cells were infected with rQNestin34.5 and then injected into mice to see if neuroblastoma tumors would form. Tumors did not form in any of the mice over a 60-day observation period, leading the researchers to report that rQNestin34.5 "abolished tumor growth" by attacking apparent tumor-initiating cells.

In comparison experiments for control, researchers also infected tumorigenic cells with another oncolytic herpes virus called rQLuc, which does not target cells that contain the nestin protein. Next to rQNestin34.5, rQLuc showed only moderate success, with all treated mice having tumor formation within 40 days. In mice where cells were treated only with saline, all animals had tumors form within 30 days.

Although a promising step forward, Dr. Cripe said the study's main limitation is that precancerous cells were infected with the oncolytic virus in a laboratory culture before being injected into mice.

"Targeting and hitting the cells after they are already in the mice will be another matter," he said.

The research team also nurtured the stem-cell like tumorigenic cultures over an extended period of time in the laboratory. In the next research phase, the team will try to verify results in the current study by seeing if they can detect the presence of cancer stem cells in primary neuroblastoma tumor cells from patients.

Dr. Cripe cautioned much more research is needed before determining whether rQNestin34.5 would be efficacious in treating neuroblastoma patients in a clinical setting.


'/>"/>

Contact: Nick Miller
nicholas.miller@cchmc.org
513-803-6035
Cincinnati Children's Hospital Medical Center
Source:Eurekalert

Related medicine news :

1. FDA Issues Final Regulations for Genetically Engineered Animals
2. E. coli engineered to produce important class of antibiotic, anti-cancer drugs
3. Top Athletes Join Forces for a New Mission: Athlete-Engineered Skincare to Support Performance and Benefit Charity
4. FDA Proposes Regulations for Genetically Engineered Animals
5. Tumor suppressor genes speed up and slow down aging in engineered mouse
6. OrbusNeich Receives Approval to Market Genous(TM) Bio-engineered R stent(TM) in Taiwan
7. Symposium at Angioplasty Summit TCT Asia Pacific 2008 Features OrbusNeichs Genous(TM) Bio-engineered R stent(TM)
8. Reconstructing mandibular defects with bioengineered tooth and bone
9. Nanomedicine system engineered to enhance therapeutic effects of injectable drugs
10. 5,000 Patients Treated With OrbusNeichs Genous(TM) Bio-engineered R Stent(TM) Now Enrolled in Real-Life Use Global Registry
11. T vs. B: Re-engineered human T cells effectively target and kill cancerous B cells
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:8/16/2017)... ... 16, 2017 , ... Paul Vitenas, MD, FACS , is honored to ... annual list identifies the nation’s top physicians, in a variety of specialties. This marks ... top of Castle Connolly’s coveted ranking. , Castle Connolly is the nation’s trusted provider ...
(Date:8/16/2017)... ... August 16, 2017 , ... SGNA Standards of Infection Control ... cycle, both between patient procedures and before storage, is a requisite practice crucial ... to the prevention of disease transmission and nosocomial infection as cleaning and HLD.” ...
(Date:8/16/2017)... ... August 16, 2017 , ... Richard Strawn’s new ... during the time of a cancer diagnosis, surgery and recovery, the Psalms provided ... the many ways God shows love to those who are sick., Surgical Psalms ...
(Date:8/16/2017)... , ... August 16, 2017 , ... ... offering an opportunity for men and women to train as hospice volunteers. Volunteers ... with life-limiting illness. For over 30 years, the agency has trained volunteers to ...
(Date:8/16/2017)... ... August 16, 2017 , ... Rollon Skin Care ... skincare solutions, recently announced the launch of two new skincare products, Prache Antiaging ... alternative to expensive plastic surgery or in-patient cosmetic dermatological procedures. , “Prache Antiaging ...
Breaking Medicine News(10 mins):
(Date:8/2/2017)... , Aug. 2, 2017 Fenita ... Who as a Pinnacle Lifetime Professional in the ... Account Manager at Turing Pharmaceuticals, AG. Her skills ... and relationship building.                ... than 25 years of experience as a highly ...
(Date:8/2/2017)... 2017 CaryRx, a next-generation full-service pharmacy, has announced ... patients in the Washington D.C. metropolitan ... providing delivery of medications through the convenience of its patient-friendly ... delivered within one hour to any location in D.C. ... this invaluable service to Washington D.C. ," says ...
(Date:7/31/2017)... July 31, 2017 Three Tru-D SmartUVC robots have ... South Korea . Tru-D, short for "Total Room Ultraviolet Disinfection," is ... after an environmental services (ES) professional cleans the area with traditional cleaning ... Tru-D fights ... "Although the BAACH has a ...
Breaking Medicine Technology: