Plastic surgery laser could hold key to targeting body ’ s anti-cancer response
Unexpected research shows how to strengthen role of immune cells
The use of a new cosmetic laser could improve the effectiveness of certain anti-tumour therapies and extend their use to more diverse forms of cancer .
The strategy , using a laser invented at Massachusetts General Hospital , has so far been only tested and validated in mice in an attempt to expand the benefits of immune checkpoint inhibitors for patients who do not benefit from the drugs , which boost the immune system ’ s response to various cancers .
Researchers at the hospital found that exposing melanoma cells to ultraviolet radiation caused them to take on more mutations , which made immune checkpoint inhibitors more effective at boosting the body ’ s immune response against the melanomas .
Unexpectedly , the enhanced response also included an immune system attack against non-mutated proteins in the tumour in a process called epitope spreading .
“ Epitope spreading could be important because many human cancers do not have very high mutation numbers , and correspondingly do not respond well to immunotherapy , so a treatment that can safely target non-mutated proteins could be valuable ,” said study leader Dr David E . Fisher on announcing the findings .
The researchers next sought to find a substitute for the response triggered by the mutations caused by ultraviolet radiation , since adding mutations to a patient ’ s tumour as a treatment strategy is unlikely to be safe .
“ We discovered that use of a cosmetic laser , also known as a fractional laser , when shined on a tumour , could trigger a form of local inflammation that mimicked the presence of mutations , strongly enhancing immune attacks against non-mutated tumour proteins , thereby curing many mice of tumours that otherwise did not respond to immunotherapy ,” he said .
The findings suggest that using this laser approach , or other methods to optimise immune responses against non-mutated targets on tumours , might make immune checkpoint inhibitors effective against currently incurable cancers .
Urine test for cancer may one day be in the cards
Research findings change the way scientists think about cancer DNA fragments in urine
U
rine samples could be used to detect cancers at their earliest stages , when the disease responds most favourably to treatment .
That ’ s according to a team of scientists from the Translational Genomics Research Institute ( TGen ) in Arizona ( US ), who have found a way of zeroing in on early-stage cancer by analysing short strands of cell-free DNA in urine .
It was previously believed that DNA fragments in urine were too random and short to provide any meaningful information about a disease as complex as cancer . But the researchers have found that these fragments are not random at all , and can clearly indicate a difference between healthy individuals and those with cancer .
“ There are many steps between where we are now and where we want to go — detecting cancer from a urine sample — but without doubt this is an encouraging first step ,” said Dr Muhammed Murtaza , the study ’ s senior author and director of the Centre for Noninvasive Diagnostics at TGen , on the announcement of the findings .
By studying tissue samples from children with various cancers , whose malignancies often move extraordinarily fast , and adults with pancreatic cancer , whose early detection is critical to their disease outcomes , the researchers mapped the DNA fragmentation profiles in their urine .
“ We found that certain regions of the genome are protected from fragmentation in urine from healthy individuals , but the same regions are more fragmented in patients with cancer ,” Dr Murtaza said .
The fragmentation profiles were remarkably similar across multiple individuals , e . g ., the length of the DNA fragments were similar and the regions of the genome where the fragmentation occurred were consistent , which informed researchers what type of cells contributed the fragments .
If the study come to fruition , urinalysis would be a remarkable breakthrough in the detection of many cancers . While early results are promising , the researchers now need to test their findings in much larger populations of cancer patients .
22 APRIL 2021 GlobalHealthAsiaPacific . com