Page URL:

CRISPR used to uncover new drug targets for cancer

2 October 2017
Appeared in BioNews 920

New potential drug targets have been identified for cancers associated with KRAS gene mutations, which are thought to drive around 20-30 percent of all human cancers.

Researchers used CRISPR genome editing to identify two genesNADK and KHK, which markedly reduced the growth of human colorectal cancer cells with KRAS mutations when inactivated in a mouse model. The team also found new 'tumour suppressor' genes – those involved in keeping cancers at bay.

'One of the most surprising findings from our study is how performing this type of genetic screen directly in a mammalian microenvironment revealed not only new synthetic lethal interactions, but also new tumour suppressor genes that are dependent on KRAS mutations,' said Dr Edwin Yau of the University of California San Diego (UCSD), and first author of the study.

Cancers caused by KRAS mutations include lung, pancreatic and colorectal cancer - often the most lethal and difficult to treat.

While previous research has focused on directly targeting mutant KRAS proteins to treat cancer, with limited success, researchers at the UCSD's School of Medicine decided to search for other genes which kill KRAS-mutated cancer cells when inhibited.

The team used genome editing to systematically inactivate every gene in the genomes of two human colorectal cancer cell lines with and without the KRAS mutation.

They then investigated whether inactivating these genes affected the ability of the cancer cells to grow in mice.

Inhibiting NADK and KHK, which code for metabolic enzymes, reduced the growth of KRAS-mutant colorectal cancer cells in mice by about 50 percent. There was no effect on cells with normal KRAS.

Crucially, the team saw these results only when the cancer cells were grown in mice rather than in vitro. The mammalian system provides 'a more realistic microenvironment where the tumour has to survive' explained Dr Tariq Rana, who led the study.

The researchers also found other genes that, when inactivated, had the opposite effect of NADK and KHK. These tumour suppressor genes increased the growth of KRAS-mutant tumours, but not of normal KRAS tumours. 

The team now want to carry out further research to better understand how KRAS-mutant cancers develop.

The study was published in Cancer Research.

The latest developments in genome editing will be discussed at the session 'What Next for Genome Editing? Politics and the Public', at the Progress Educational Trust's upcoming public conference 'Crossing Frontiers: Moving the Boundaries of Human Reproduction'.

The conference is taking place in London on Friday 8 December 2017. Full details - including sessions, speakers and how to book your place - can be found here.

CRISPR-Cas9 used to systematically inactivate genes in colorectal cancer
Drug Target Review |  28 September 2017
Editing genes one by one throughout colorectal cancer cell genome uncovers new drug target
EurekAlert |  27 September 2017
Genome-wide CRISPR screen for essential cell growth mediators in mutant KRAS colorectal cancers
Cancer Research |  27 September 2017
15 April 2019 - by Charlotte Spicer 
UK scientists have used genome-editing to identify hundreds of potential drug targets for new cancer treatments...
16 July 2018 - by Jen Willows 
Cancer cells may be edited to attack tumours according to new research published in Science Translational Medicine...
14 May 2018 - by Shaoni Bhattacharya 
Researchers have slowed the growth of pancreatic cancer by harnessing genome editing to remove key molecules implicated in its spread...
15 January 2018 - by Rikita Patel 
The human adaptive immune response against the Cas9 protein - part of the CRISPR genome editing system – may pose a barrier to new therapies, suggests a new study...
18 September 2017 - by Dr Molly Godfrey 
Organoids and CRISPR/Cas9 have been combined in a novel method to study genetic mutations occurring in cancer...
14 August 2017 - by Ebtehal Moussa 
Over a 100 new genes that may be essential for cancer immunotherapy to work have been identified using a new CRISPR-based screen...
15 May 2017 - by Isobel Steer 
Cancer-related mutations have been found in tissue taken from patients with deep endometriosis...
24 April 2017 - by Jennifer Willows and Annabel Slater 
A new highly sensitive diagnostic system for diseases has been adapted from CRISPR...
12 December 2016 - by Ayala Ochert and Ebtehal Moussa 
Researchers have successfully treated a woman with colon cancer using her own immune cells to target a cancer-causing gene that had previously been considered 'undruggable'...
to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.