About My Health Careers Internship MedBlogs Contact us

Tumors may Become Resistant due to 'Ras' Gene Mutations

by Rishika Gupta on December 27, 2017 at 12:23 PM
Font : A-A+

Tumors may Become Resistant due to 'Ras' Gene Mutations

Mutations in 'Ras' genes known to drive around 25% of human cancers, can protect the cancer cells from the immune system. These genes can suppress the immune system by increasing 'PD-L1' protein level. The findings of this study are further discussed in Immunity journal.

The research shows that mutated Ras genes can suppress the immune system around tumors by increasing levels of a protein called 'PD-L1'. Small amounts of PD-L1 exist naturally in the body to prevent the immune system from attacking healthy cells, but cancer cells can exploit this to protect themselves.


"Understanding how different mutations protect cancer cells from the immune system will help us to offer patients more precise and effective treatments," explains Dr. Matthew Coelho, first author of the paper from the Francis Crick Institute. "Antibodies that target PD-L1 proteins are currently used in the clinic, and they work very well in around a fifth of lung cancer patients. At the moment, doctors can measure PD-L1 levels to help determine which patients might respond best, but this only gives you half of the story".

"For cancer immunotherapies targeting PD-L1 to work, you need two things: Firstly, you need PD-L1 to be blocking an immune attack in the patient's tumor. Secondly, the immune system is only able to recognize and attack cancer cells that produce 'antigens', molecules that immune cells can bind to. Cancer antigens are currently difficult to test for clinically, so PD-L1 is now a major test for deciding if immunotherapy will work. It is therefore very important to understand what turns on PD-L1 in cancer."

By revealing the causal link between Ras and PD-L1 levels, and the mechanisms behind it, the new study offers new possibilities for combination therapies using different drugs. As part of the study, mice with Ras mutant cancers were given compounds to counteract the effects of Ras signaling on PD-L1 expression. Their tumors were attacked by the immune system, slowing tumor growth.

"Our study highlights the fundamental role that Ras mutations play throughout the different stages of cancer," explains senior author Professor Julian Downward, Group Leader at the Francis Crick Institute and Head of the Lung Cancer Group at the ICR.

"We already knew that they played a key role in starting around a quarter of all human cancers, causing cancer cells to grow, multiply and spread. We now know that they also help to protect the cancer cells from our immune systems, making them more difficult to treat. Understanding the mechanisms behind this will help us to develop better treatments in future, for example boosting immunotherapy approaches with drugs that disrupt cancer's defenses." said Professor Julian Downward.

Source: Eurekalert

News A-Z
News Category
What's New on Medindia
Is COVID-19 Vaccination during Pregnancy Safe?
Sensory Processing Disorder (SPD)
View all

Medindia Newsletters Subscribe to our Free Newsletters!
Terms & Conditions and Privacy Policy.

More News on:
DNA Finger Printing McArdle Disease Weaver Syndrome 

Recommended Reading
Colorectal Cancer Due To Mutations in APC Protein
Mutations in the Adenomatous polyposis coli protein affect the immune system and create favorable .....
Rare Mutation Reduces Sensitivity to Pain
Rare mutation in Italian family causes them to experience congenital analgesia, a rare inherited ......
Melanoma Risk can be Seen in Family Members Without Inherited Mutations
Melanoma Risk May Not Be Avoidable Even In Family Without Inherited Mutation. Malignant melanoma .....
Cancer Treatment Outcome Predicted by Mutation in Tumor DNA
Higher 'mutational burden' predicts which cancer types will respond to therapies known as ......
DNA Finger Printing
DNA fingerprinting is a technique which helps forensic scientists and legal experts solve crimes, id...
McArdle Disease
McArdle disease is a genetic disorder in which the body cannot breakdown glycogen in the muscles. It...
Weaver Syndrome
Weaver syndrome is a genetic disorder in which children show accelerated bone growth, advanced bone ...

Disclaimer - All information and content on this site are for information and educational purposes only. The information should not be used for either diagnosis or treatment or both for any health related problem or disease. Always seek the advice of a qualified physician for medical diagnosis and treatment. Full Disclaimer

© All Rights Reserved 1997 - 2021

This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use