Scientists studying a rise in rare and unusual cancers in young people are turning their attention to an unlikely culprit: Covid.
Preliminary cell research has indicated that the virus can drive the growth of tumors and disable the body’s defenses against them, but the theory is widely disputed.
However, there is a consensus among doctors: after the pandemic, more and more young and relatively healthy people are suffering from obscure forms of the disease.
One doctor told DailyMail.com that the theory that Covid is driving these cases doesn’t hold water because the trend predates the outbreak. Early-onset cancers of all forms have been on the rise, increasing 79 percent between 1990 and 2019 globally, according to an analysis published in BMJ Oncology last year.
Others found the Covid theory more convincing. They pointed out that already one in four cancers is related to other viruses, such as HPV.
The graph above shows the change in cancer case rates around the world.
Kasra Jahankhani, Iranian immunologist and senior researcher on a 2023 report on the topic told DailyMail.com: “It’s really controversial and there’s a lot of debate on the topic, but we think there are many ways that SAR and Covid infection could affect cancers.”
Their research suggested that the coronavirus may change genes that normally prevent tumors from forming and cause widespread inflammation throughout the body.
This inflammation, combined with a reduction in defenses, could lead to the development of cancer cells in various organs, they wrote.
Viral associations with cancer are “unfortunately common,” said Dr. Landau, an oncologist and collaborator with the Mesothelioma Center in Asbestos.com.
In the case of the human papillomavirus (HPV), for example, it is believed that the virus itself can inject its DNA into the body’s cells, which can cause a mutation that leads to the growth of cancer cells.
«Basically, the virus tries to take over the cells of our body to promote its own growth and survival.
“But mutating cells so that they grow continuously is, at a simple level, how cancers develop,” Dr. Landau told DailyMail.com.
However, not all experts agree. Dr. Suneel Kamath, an oncologist at the Cleveland Clinic, ruled out a link between Covid and cancer.
“Trends in the increasing incidence of cancers in younger people, such as bile duct, colorectal, breast, lung and gastric cancer, have been occurring for years, even decades before the Covid-19, and they are still happening,” he told DailyMail. com.
Viral associations with cancer are “unfortunately common,” said Dr. Landau, an oncologist and contributor to the Mesothelioma Center at Asbestos.com.
Research has suggested that the coronavirus may change genes that normally prevent tumors from forming and cause widespread inflammation throughout the body.
Diagnoses of colon cancer, particularly among those under 50, have reached epidemic levels. Nearly 18,000 cases are diagnosed among this age group in the U.S. each year, compared to 12,000 per year before 2000.
Colon cancer deaths among young people are also expected to double between now and 2030, experts have warned.
Uterine cancer has also increased two percent each year in people under age 50 since the mid-1990s.
Early-onset breast cancer also increased 3.8 percent annually between 2016 and 2019, and cancer rates do not appear to have accelerated dramatically since Covid.
But experts have said it may be too early to see that impact, as “the long-term implications of the pandemic will evolve over time,” Dr. Landau said.
CDC data shows that more people are now being told they have cancer than before the pandemic. In 2021, 9.8 percent of adults They reported that a doctor had once told them they had cancer. In 2019, that proportion of adults was 9.5 percent.
One of the possible links between Covid and cancer is a gene called P53, which suppresses cancerous tumors in the body by stopping cells with mutated or damaged DNA from dividing, Jahankhani explained.
His research team discovered that the P53 tumor suppressor gene can be “degraded” by SARS-CoV-2 and effectively blocked.
This means that it can no longer stop tumors from growing. Other research has found that lower levels of P53 can make people more susceptible to cancer.
Another factor involves the renin-angiotensin-aldosterone system (RAAS), which is a key system that regulates blood pressure in the body.
When the SARS-CoV-2 virus binds to the ACE2 receptor, it prevents the RAAS from working properly.
This, in turn, causes inflammation and oxidative stress, which are factors in cancer progression and development.
Another way Covid and cancer could be linked is through proteins called cytokines.
When the body contracts an infection like Covid, the immune system will begin to fight it, including using cytokines as a defense system against the virus.
The photo shows the coronavirus indicated in yellow, emerging from the surface of cells, indicated in blue/pink, grown in a laboratory. Research suggests that the virus can awaken dormant cancer cells and cause inflammation throughout the body that can lead to the proliferation of cancer cells.
The proteins tell the immune cells what to do and also tell the body to produce more to ensure that the infection is dealt a killing blow.
But sometimes too many cytokines can be released, putting the immune system into overdrive and creating a heightened inflammatory response.
The release of cytokines is often what makes us feel sick when we have an infection, Dr. Landau said.
“But these same cytokines can cause damage to the body, and that damage can increase the risk of cancer, especially if they remain elevated long term,” he said.
This heightened inflammatory response occurs with long Covid, he added.
Too much inflammation can damage tissues and DNA and has been linked to the development of autoimmune diseases, as well as cancer.
Inflammation also causes changes in the chromosomes of cells, and repeated changes can cause cells to become cancerous.
This abundance of cytokines can also lead to the appearance of cancer stem cells in organs such as the lungs and pancreas, as well as the bile ducts.
Because Covid infection occurs directly and indirectly in several organs, including the lungs, brain and kidneys, researchers believe that cancer stem cells can develop in multiple organs.
Stem cells are cells that have the ability to become many different types of cells in the body.
Meanwhile, cancer stem cells are found in tumors and have the ability to divide and renew themselves, causing the tumor to grow and spread.
They can originate from adult tissue stem cells and start a tumor, especially if there is a lot of inflammation from Covid.
And while researchers cannot definitively rule out that Covid vaccines play a role, Jahankhani said there is no evidence that is the case.
His team “found nothing” to support the idea that the Covid shot increased cancer rates.
The evidence supporting the virus theory appears to be much stronger, he added.
Dr. Landau acknowledged that although there have been problems with blood clots after the Covid vaccine, “a clear link to the development of cancer is not yet known.”
“We suspect the cancer risk would come from the virus itself, rather than the vaccine, but it will take years of follow-up studies to really understand this,” he said.