Cancer cells can change their size to evade treatment, scientists have discovered.
The new findings could lead to treatment being put to better use while new therapy could slow down the disease by focusing on proteins involved in regulating cell size.
Experts at the Institute of Cancer Research London combined biochemical profiling technology with mathematical work to show how genetic changes lead to differences in the size of cancer cells.
The researchers believe smaller cells could be more vulnerable to DNA-damaging agents such as chemotherapy combined with drugs, while larger cells might respond better to immunotherapy, which harnesses the power of a patient's immune system.
The study, published in the journal Science Advances, involved examining millions of skin cancer cells.
But the team believe their findings may also apply to other cancers. They have already identified similar mechanisms in breast cancer and are now looking at head and neck cancers.
“This intriguing, fundamental study provides a correlation between genetic alterations in skin cancer cells and cell size," said Prof Kristian Helin, chief executive of the ICR.
“It opens the potential of using genetic alterations and cell size as biomarkers for how skin cancer will respond to treatments.
“It’s particularly exciting that cell size could also be an important biomarker for how other cancers, such as breast or head and neck cancers, respond to treatments.”
Products that contain cancer-causing chemical - in pictures
-
Many dry shampoos contain benzene, a carcinogen known to cause cancer, according to tests carried out by independent US lab Valisure. Photo: Unsplash -
Last year, Valisure raised the alarm about benzene levels in hand sanitisers, body sprays and sunscreens, several of which were also recalled. Photo: Getty -
In 2021, several brands of sun cream were found to contain unsafe levels of benzene. Photo: Getty -
Some deodorants brands have also been found to contain benzene. Photo: Getty -
Studies have revealed that women who have used hair straightening chemicals, or relaxers, may be at higher risk of developing uterine cancer. Photo: Getty -
Some studies show a link between the chemicals in certain hair dyes and cancer. But it has been found that the risk is probably low in people who colour their hair from time to time. People who work with dye all day long, are at a greater risk. Photo: Getty
The researchers investigated the differences in size and shape of skin cancer cells harbouring two genetic mutations.
The skin cancer melanoma is driven by two different genetic mutations, with 60 per cent of cases caused by one known as BRAF, and 20 to 30 per cent caused by one called NRAS.
The study found a major difference in cell size. BRAF-mutant cancer cells were very small, whereas NRAS-mutant cancer cells were much bigger, and drug-resistant NRAS cells bigger still.
The experts said that smaller cells appeared to be able to tolerate higher levels of DNA damage because of a high concentration of proteins that repair DNA.
Hidden nitrates found in processed foods - in pictures
-
An average hot dog sausage contains about 50 micrograms of nitrates per 100g of meat. Photo: AFP -
Bacon is incredibly high in both nitrites and nitrates, with up to 380 mcg of nitrates per five rashers. Photo: AFP -
Deli meats such as salami, pastrami and prosciutto are a major source of harmful nitrates. Photo: Reuters -
Although nitrates have been removed by the smoking process of many brands, some smoked salmon still contains high levels of sodium nitrates. Photo: Boa
This means these cells could be attacked with chemotherapy and drugs such as PARP inhibitors, which block the proteins responsible for repairing DNA damage.
In contrast, the larger NRAS-mutant cancer cells contained damage to their DNA instead of repairing it, which means chemotherapy and PARP inhibitors may not be as effective.
Scientists believe these larger cells could be more responsive to immunotherapy.
“We think of cancer as out of control and unpredictable, but we used image analysis and proteomics (study of proteins) to show for the first time that certain genetic and protein changes lead to a controlled change in the size of cancer cells," said the study leader, Prof Chris Bakal.
“Cancer cells can shrink or grow to enhance their ability to repair or contain DNA damage, and that in turn can make them resistant to certain treatments.
World Cancer Day 12 celebrities opened up about having the disease - in pictures
-
Actress Sofia Vergara had thyroid cancer when she was 28 years old. AFP -
Hugh Jackman has been diagnosed with basal cell carcinoma, a malignant type of skin cancer, several times. AFP -
US comedian Kathy Griffin was recently declared cancer free after having half her left lung removed. RB/Bauer-Griffin/GC Images -
Michael C Hall had Hodgkin's lymphoma while filming hit TV series 'Dexter'. AFP -
Former NBA star Kareem Abdul-Jabbar has had both prostate cancer and chronic myeloid leukemia. AFP -
Actor Ben Stiller was treated for prostate cancer in 2014. AFP -
Bollywood actress Sonali Bendre had metastatic cancer in her abdomen. AFP -
Nepalese actress Manisha Koirala had ovarian cancer in 2012. AFP -
British TV personality Sharon Osbourne was diagnosed with colon cancer in 2002, and also had a double mastectomy in 2012 after finding out she had the gene that increases risk of getting breast cancer. AFP -
Khloe Kardashian has been treated for skin cancer in the past. AFP -
Lebanese singer Elissa has famously discussed her journey with breast cancer. AFP -
Egyptian actor Ahmed Helmy underwent treatment for cancer while his wife, Mona Zaki, was pregnant with their child. AFP -
From left: Ahmed Helmy, Khloe Kardashian and Manisha Koirala have all opened up about their cancer journeys. Photos: Front Row, AP Photo, AFP
“We think our research has real diagnostic potential. By looking at cell size, pathologists could predict whether a drug will work, or if the cells will be resistant.
“In the future, it might even be possible to use AI to help guide the pathologist, by making a rapid assessment about the size of cells and so the treatments that are most likely to work.
“We also hope our discovery will lead to new treatment strategies — for example, creating drugs to target the proteins that regulate cell size.”
