‘Sugary foods fuel cancers’
*New test may improve pancreatic tumour diagnosis, treatment outcomes
*US agency approves first drug to target genetic traits, rather than body parts
A sugar rich diet may be fuelling various forms of cancer, as new research confirms a long suspected belief.Previous studies have suggested that tumours thrive off sugar, using it as energy to mutate and spread across the body.
Now scientists have shown one type of cancer – which can be found in the lungs, head and neck, oesophagus and cervix – has more of a sweet tooth than others.
Squamous cell carcinoma (SqCC) was more dependent on sugar to grow, University of Texas at Dallas, United States (US), experts found.This form of the disease used higher levels of a protein that carries glucose to cells to enable them to multiply, they discovered.
Previous studies have suggested that tumours thrive off sugar, using it as energy to mutate and spread across the body. Lead author, Dr. Jung-whan Kim, said: “It has been suspected that many cancer cells are heavily dependent on sugar as their energy supply. But it turns out that one specific type – squamous cell carcinoma – is remarkably more dependent.
“This type of cancer clearly consumes a lot of sugar. One of our next steps is to look at why this is the case.”Writing in the journal Nature Communications, he warned the findings were worrying because “as a culture, we are very addicted to sugar”.
Meanwhile, a new study describes a blood test that may aid the diagnosis of pancreatic cancer and someday make earlier screening feasible, the authors say.
The test detects a combination of five tumor proteins that appear to be a reliable signature of the disease, the researchers report in the May 24 Science Translational Medicine. In patients undergoing pancreatic or abdominal surgery, the test was 84 percent accurate at picking out those who had pancreatic cancer.
Individuals with the most common form of pancreatic cancer, called pancreatic ductal adenocarcinoma, have a five-year survival rate of less than 10 percent. The cancer is usually caught late because the symptoms, including weight loss and abdominal pain, often do not arise until the cancer has spread.
Also, United States (US) regulators have approved the first ever cancer drug that treats specific traits of their disease, rather than the body part it started in.
The move is being hailed as a breakthrough that could change the future of cancer care.It means patients can get more specific care, and could provide a lifeline to those who are not eligible for mainline treatment since their disease has spread.
Keytruda, made by Merck & Co, is a form of immunotherapy which targets solid tumors with a biomarker called microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR).
These biomarkers are common in colorectal, endometrial and gastrointestinal cancers, but may also appear in cancers of the breast, prostate, bladder, pancreas, thyroid gland and others.
The FDA accelerated approval for the drug to be used for solid tumor cancers not eligible for surgery or that have spread in patients with MSI-H or dMMR. Patients whose tumors are laden with the genetic defect have an abundance of abnormal proteins that look more foreign to immune cells, triggering them to search out and destroy the cancer cells.
Keytruda belongs to a new class of drugs called PD-1 that block a mechanism tumors use to evade detection from cancer-fighting cells. There are now five such drugs available for a variety of cancers.
Tests for the specific genetic defects are widely available, costing between $300 and $600. The approval covers children and adults whose cancer has progressed despite prior treatment and those who have no satisfactory alternative treatment options, including patients whose colorectal cancer has progressed following chemotherapy.