International
Scientists discover how air pollution triggers lung cancer
AFP | by Daniel Lawler and Isabelle Cortes
Scientists said Saturday they had identified the mechanism through which air pollution triggers lung cancer in non-smokers, a discovery one expert hailed as “an important step for science — and for society”.
The research illustrated the health risk posed by the tiny particles produced by burning fossil fuels, sparking fresh calls for more urgent action to combat climate change.
It could also pave the way for a new field of cancer prevention, according to Charles Swanton of the UK’s Francis Crick Institute.
Swanton presented the research, which has not yet been published in a peer-reviewed journal, at the European Society for Medical Oncology’s annual conference in Paris.
Air pollution has long been thought to be linked to a higher risk of lung cancer in people who have never smoked.
“But we didn’t really know whether pollution was directly causing lung cancer — or how,” Swanton told AFP.
Traditionally it has been thought that exposure to carcinogens, such as those in cigarette smoke or pollution, causes DNA mutations that then become cancer.
But there was an “inconvenient truth” with this model, Swanton said: previous research has shown that the DNA mutations can be present without causing cancer — and that most environmental carcinogens do not cause the mutations.
His study proposes a different model.
A future cancer pill?
The research team from the Francis Crick Institute and University College London analysed the health data of more than 460,000 people in England, South Korea and Taiwan.
They found that exposure to tiny PM2.5 pollution particles — which are less than 2.5 microns across — led to an increased risk of mutations in the EGFR gene.
In laboratory studies on mice, the team showed that the particles caused changes in the EGFR gene as well as in the KRAS gene, both of which have been linked to lung cancer.
Finally, they analysed nearly 250 samples of human lung tissue never exposed to carcinogens from smoking or heavy pollution.
Even though the lungs were healthy, they found DNA mutations in 18 percent of EGFR genes and 33 percent of KRAS genes.
“They’re just sitting there,” Swanton said, adding that the mutations seem to increase with age.
“On their own, they probably are insufficient to drive cancer,” he said.
But when a cell is exposed to pollution it can trigger a “wound-healing response” that causes inflammation, Swanton said.
And if that cell “harbours a mutation, it will then form a cancer”, he added.
“We’ve provided a biological mechanism behind what was previously an enigma,” he said.
In another experiment on mice, the researchers showed that an antibody could block the mediator — called interleukin 1 beta — which sparks the inflammation, stopping cancer from getting started in the first place.
Swanton said he hoped the finding would “provide fruitful grounds for a future of what might be molecular cancer prevention, where we can offer people a pill, perhaps every day, to reduce the risk of cancer”.
Revolutionary
Suzette Delaloge, who heads the cancer prevention programme at France’s Gustave Roussy institute, said the research was “quite revolutionary, because we had practically no prior demonstration of this alternative way of cancer forming.
“The study is quite an important step for science — and for society too, I hope,” she told AFP.
“This opens a huge door, both for knowledge but also for new ways to prevent” cancer from developing, said Delaloge, who was not involved in the research but discussed it at the conference on Saturday.
“This level of demonstration must force authorities to act on an international scale.”
Tony Mok, an oncologist at the Chinese University of Hong Kong, called the research “exciting”.
“It means that we can ask whether, in the future, it will be possible to use lung scans to look for pre-cancerous lesions in the lungs and try to reverse them with medicines such as interleukin 1 beta inhibitors,” he said.
Swanton called air pollution a “hidden killer”, pointing to research estimating it is linked to the deaths of more than eight million people a year — around the same number as tobacco.
Other research has linked PM2.5 to 250,000 deaths annually from lung cancer alone.
“You and I have a choice about whether we smoke or not, but we do not have a choice about the air we breathe,” said Swanton, who is also the chief clinician at Cancer Research UK, which was the main funder of the research.
“Given that probably five times as many people are exposed to unhealthy levels of pollution than tobacco, you can see this is quite a major global problem,” he added.
“We can only tackle it if we recognise the really intimate links between climate health and human health.”
International
Man arrested after deliberately driving into seven children in Osaka
Japanese police arrested a man on Thursday after he rammed his car into a group of seven schoolchildren in an apparent deliberate attack in the city of Osaka.
The children, who were on their way home from school, sustained injuries and were taken to the hospital. All seven remained conscious, according to local authorities.
An Osaka police officer, speaking on condition of anonymity, said the suspect is a 28-year-old man from Tokyo. The officer shared statements the man made after his arrest: “I was fed up with everything, so I decided to kill people by driving into several elementary school children,” the suspect reportedly said.
The man has been arrested on suspicion of attempted murder.
The injured children, aged between seven and eight, included a seven-year-old girl who suffered a fractured jaw. The six other children—all boys—suffered minor injuries such as bruises and scratches and were undergoing medical evaluation.
Witnesses described the car as “zigzagging” before hitting the children. One witness told Nippon TV that a girl was “covered in blood” and the others appeared to have scratches.
Another witness said the driver, who was wearing a face mask, looked to be in shock when school staff pulled him from the vehicle.
Violent crimes are rare in Japan, though serious incidents do occur from time to time. In 2008, Tomohiro Kato drove a two-ton truck into pedestrians in Tokyo’s Akihabara district, then fatally stabbed several victims. Seven people were killed in that attack.
Internacionales
Clashes erupt during may day protests across France amid calls for better wages
May Day protests in France were marked by a heavy police presence and clashes between demonstrators and law enforcement in several cities.
In Paris, Lyon, and Nantes, thousands took to the streets to demand better wages, fairer working conditions, and to voice their dissatisfaction with President Emmanuel Macron’s government.
While the majority of the demonstrations remained peaceful, isolated confrontations broke out in some areas. Protesters threw objects at the police, prompting the use of tear gas and resulting in several arrests.
Videos showing police crackdowns circulated widely on social media, drawing criticism from labor unions and human rights advocates, who denounced the authorities’ response to the protests.
International
Kristi Noem credits Trump for mass migrant deportations by mexican president
U.S. Secretary of Homeland Security Kristi Noem claimed that Mexican President Claudia Sheinbaum has deported “more than half a million” migrants due to pressure from former President Donald Trump.
During a cabinet meeting highlighting the “achievements” of Trump’s administration in its first 100 days, Noem asserted that under the Republican leader’s influence, “Mexico has finally come to the table” to negotiate on migration and fentanyl trafficking.
“The president of Mexico told me she has returned just over half a million people before they reached our border,” Noem stated, criticizing media reports that suggest the Biden administration deported more migrants than Trump’s.
“I wish those deportations were counted,” Noem added, “because those people never made it to our border—she sent them back because you made her.” She went on to thank Trump: “They never made it here because they got the message—because you were so aggressive.”
Noem has made controversial claims about Sheinbaum in the past, prompting the Mexican leader to refute them.
On April 1, Sheinbaum responded to one such statement by declaring, “The president answers to only one authority, and that is the people of Mexico,” after Noem said on Fox News that she gave Sheinbaum “a list of things Trump would like to see” and that Mexico’s actions would determine whether Trump granted tariff relief.
Man arrested after deliberately driving into seven children in Osaka
Clashes erupt during may day protests across France amid calls for better wages
Kristi Noem credits Trump for mass migrant deportations by mexican president
Tec de Monterrey honors one of its students for his contribution to nanotechnology in medicine
Defense Minister commends salvadoran soldier for Central American Cross Country victory
Extension of the state of emergency approved in southern Chile
-
International3 days agoColombia sees deadliest surge in violence since FARC peace deal
-
International5 days agoNine dead after driver runs over crowd at Vancouver Street Festival
-
Central America3 days agoGuatemala sees road blockades amid protests against lawmaker pay hikes
-
International3 days agoConclave to choose pope Francis’ successor could begin in early may
-
International5 days agoKing Charles III expresses deep sadness after Vancouver festival tragedy that left nine dead
-
International3 days agoSpain’s PM calls for calm and patience amid ongoing blackout
-
International3 days agoMexican activist who exposed pornography ring found dead in Veracruz
-
International3 days agoMadrid carries out 286 elevator rescues amid massive blackout
-
International1 day agoVatican releases special “Sede Vacante” stamps ahead of papal transition
-
International1 day agoKristi Noem credits Trump for mass migrant deportations by mexican president
-
Internacionales10 hours agoClashes erupt during may day protests across France amid calls for better wages
-
International10 hours agoMan arrested after deliberately driving into seven children in Osaka