Nav: Home

Viral gene therapy could improve results from breast reconstruction after cancer treatment

January 24, 2018

A new type of gene therapy delivered using a virus could protect healthy tissues from the harmful side-effects of radiotherapy after cancer treatment, a new study reports.

In the future, the treatment could be used to improve outcomes for breast reconstruction surgery in women with breast cancer - by protecting patients from scarring, shrinkage of the skin and damage to the underlying tissues.

Scientists at The Institute of Cancer Research, London, found they could prevent tissue damage in rats treated with radiotherapy by reprogramming healthy cells to protect themselves.

Modern radiotherapy is increasingly precise and targeted, but even so it can still cause a variety of side-effects to tissues including skin, fat and blood vessels, months or years after treatment.

The protection given by the new gene therapy could prevent radiotherapy side-effects in women who have had breast reconstruction surgery, and spare women a second operation to repair the damage caused by delayed side-effects.

The study is published today (Wednesday) in the journal Science Translational Medicine, and was largely funded by the Wellcome Trust.

The team at The Institute of Cancer Research (ICR), in collaboration with plastic surgeons at The Royal Marsden NHS Foundation Trust, injected rats with a modified and harmless version of a type of virus called a lentivirus.

The virus was used to deliver extra copies of a gene called SOD2, which plays a role in limiting the stress response to the harmful particles released by radiotherapy.

The team combined this with a second virally delivered treatment to block activity of a different gene involved in the scarring response to radiotherapy, called CTGF.

Six months after radiotherapy, transplanted tissues in rats that had been treated with a combination of SOD2 and CTGF gene therapy had shrunk by just 15 per cent, compared with 70 per cent in those that had not received either treatment.

The viral therapy was injected into blood vessels in tissue before it was transplanted to ensure that the protective effect was isolated only to healthy tissue away from the cancer - and to model the situation in which the gene therapy would be delivered in the clinic.

The amount of SOD2 and CTGF did not increase in the area outside the transplanted tissue - meaning that tumour cells were not protected by the treatment, and stayed vulnerable to radiotherapy.

Tumours in rats that had been treated with the gene therapy responded better to radiotherapy - with tumour growth stopped for 40 days in four out of five animals.

The findings suggest that by protecting the healthy tissues around tumours, the gene therapy increased the effectiveness of radiotherapy - although more research is needed to find out how and why this happens.

The two gene therapies targeting the CTGF gene and the SOD2 gene, respectively, seemed to counteract radiotherapy damage in healthy tissue through different mechanisms - suggesting that a combination of the two therapies would be most beneficial.

The new study opens up the possibility of offering women with breast cancer earlier reconstruction surgery, using tissues that are protected from radiotherapy side-effects. The next step will be to test out the new treatment in clinical trials.

Professor Kevin Harrington, Professor of Biological Cancer Therapies at The Institute of Cancer Research, London, said:

"We have developed a new viral gene therapy that can help healthy tissue protect itself from the damage caused even by modern, more precise forms of radiotherapy.

"Now that people with cancer are surviving longer, it is increasingly important to address the long-term impact of cancer treatments.

"Some women who need radiotherapy after a mastectomy have to wait up to six months after the end of their treatment before they can have breast reconstruction surgery, to allow time for side-effects to show themselves.

"In the future, we hope this new viral gene therapy could protect healthy tissue transplanted during cancer surgery, bringing forward the subsequent operation to reconstruct the breast."

Professor Paul Workman, Chief Executive of The Institute of Cancer Research, London, said:

"This study has found a clever new way to deliver gene therapy using a virus, so that healthy tissue is protected from radiotherapy side-effects while tumour cells remain vulnerable to the treatment.

"It's exciting that the new viral treatment has successfully protected healthy tissue and at the same time also improved outcomes in rats, and it raises the real possibility that this could become a new way of improving quality of life in cancer patients."
-end-
Notes to editors

For more information please contact Sarah Wells in the ICR press office on 020 7153 5582 or sarah.wells@icr.ac.uk. For enquiries out of hours, please call 07595 963 613.

The Institute of Cancer Research, London, is one of the world's most influential cancer research organisations.

Scientists and clinicians at The Institute of Cancer Research (ICR) are working every day to make a real impact on cancer patients' lives. Through its unique partnership with The Royal Marsden NHS Foundation Trust and 'bench-to-bedside' approach, the ICR is able to create and deliver results in a way that other institutions cannot. Together the two organisations are rated in the top four centres for cancer research and treatment globally.

The ICR has an outstanding record of achievement dating back more than 100 years. It provided the first convincing evidence that DNA damage is the basic cause of cancer, laying the foundation for the now universally accepted idea that cancer is a genetic disease. Today it is a world leader at identifying cancer-related genes and discovering new targeted drugs for personalised cancer treatment.

A college of the University of London, the ICR is the UK's top-ranked academic institution for research quality, and provides postgraduate higher education of international distinction. It has charitable status and relies on support from partner organisations, charities and the general public.

The ICR's mission is to make the discoveries that defeat cancer. For more information visit http://www.icr.ac.uk

Institute of Cancer Research

Related Breast Cancer Articles:

Does MRI plus mammography improve detection of new breast cancer after breast conservation therapy?
A new article published by JAMA Oncology compares outcomes for combined mammography and MRI or ultrasonography screenings for new breast cancers in women who have previously undergone breast conservation surgery and radiotherapy for breast cancer initially diagnosed at 50 or younger.
Blood test offers improved breast cancer detection tool to reduce use of breast biopsy
A Clinical Breast Cancer study demonstrates Videssa Breast can inform better next steps after abnormal mammogram results and potentially reduce biopsies up to 67 percent.
Surgery to remove unaffected breast in early breast cancer increases
The proportion of women in the United States undergoing surgery for early-stage breast cancer who have preventive mastectomy to remove the unaffected breast increased significantly in recent years, particularly among younger women, and varied substantially across states.
Breast cancer patients with dense breast tissue more likely to develop contralateral disease
Breast cancer patients with dense breast tissue have almost a two-fold increased risk of developing disease in the contralateral breast, according to new research from The University of Texas MD Anderson Cancer.
Some early breast cancer patients benefit more from breast conservation than from mastectomy
Breast conserving therapy (BCT) is better than mastectomy for patients with some types of early breast cancer, according to results from the largest study to date, presented at ECC2017.
One-third of breast cancer patients not getting appropriate breast imaging follow-up exam
An annual mammogram is recommended after treatment for breast cancer, but nearly one-third of women diagnosed with breast cancer aren't receiving this follow-up exam, according to new findings presented at the 2016 Annual Clinical Congress of the American College of Surgeons.
Low breast density worsens prognosis in breast cancer
Even though dense breast tissue is a risk factor for breast cancer, very low mammographic breast density is associated with a worse prognosis in breast cancer patients.
Is breast conserving therapy or mastectomy better for early breast cancer?
Young women with early breast cancer face a difficult choice about whether to opt for a mastectomy or breast conserving therapy (BCT).
Breast density and outcomes of supplemental breast cancer screening
In a study appearing in the April 26 issue of JAMA, Elizabeth A.
Full dose radiotherapy to whole breast may not be needed in early breast cancer
Five years after breast-conserving surgery, radiotherapy focused around the tumor bed is as good at preventing recurrence as irradiating the whole breast, with fewer side effects, researchers from the UK have found in the large IMPORT LOW trial.

Related Breast Cancer Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Bias And Perception
How does bias distort our thinking, our listening, our beliefs... and even our search results? How can we fight it? This hour, TED speakers explore ideas about the unconscious biases that shape us. Guests include writer and broadcaster Yassmin Abdel-Magied, climatologist J. Marshall Shepherd, journalist Andreas Ekström, and experimental psychologist Tony Salvador.
Now Playing: Science for the People

#513 Dinosaur Tails
This week: dinosaurs! We're discussing dinosaur tails, bipedalism, paleontology public outreach, dinosaur MOOCs, and other neat dinosaur related things with Dr. Scott Persons from the University of Alberta, who is also the author of the book "Dinosaurs of the Alberta Badlands".