Bacteria could become new biomarker for testing patients’ reaction to cancer treatments which would give microbiologists and clinical laboratories a new tool for aiding diagnosis and in the selection of appropriate therapies
In a surprising study conducted at King’s College London and Guy’s and St Thomas’ NHS Foundation Trust, British scientists have discovered that a common bacteria found in the mouth may be able to “melt” certain cancers. The bacteria could also be used as a clinical laboratory biomarker to determine how patients may react to specific cancer treatments.
The researchers found that the presence of Fusobacterium can help neutralize head and neck cancers and provide better outcomes in patients with those diseases, according to a Kings College London news release.
“In essence, we found that when you find these bacteria within head and neck cancers, [patients] have much better outcomes,” said Miguel Reis Ferreira, MD, PhD, clinical oncologist at Guy’s and St Thomas’, adjunct senior clinical lecturer at King’s College London and senior author of the study, in the news release. “The other thing that we found is that in cell cultures this bacterium is capable of killing cancer.”
“This research reveals that these bacteria play a more complex role than previously known in their relationship with cancer—that they essentially melt head and neck cancer cells,” said Miguel Reis Ferreira, MD, PhD (above), clinical oncologist at Guy’s and St Thomas’, adjunct senior clinical lecturer at King’s College London and senior author of the study, in a news release. “However, this finding should be balanced by their known role in making cancers such as those in the bowel get worse.” Should these findings prove sound, clinical laboratories may soon have a new biomarker for testing patients’ reaction to cancer treatments. (Photo copyright: King’s College London.)
Researchers Surprised by Their Findings
The researchers began their research by using computer modeling to identify the types of bacteria to further scrutinize. They then studied the effect of those bacteria on cancer cells by analyzing data on 155 head and neck cancer patients whose tumor information had been submitted to the Cancer Genome Atlas. Head and neck cancers include cancers of the mouth, throat, voice box, nose, and sinuses.
The scientists placed Fusobacterium in petri dishes and kept the bacteria there for a few days. They observed the effect of that bacteria on head and neck cancers and discovered there was a 70% to 90% reduction in the number of viable cancer cells after being infused with the Fusobacterium.
Due to the known correlation between Fusobacterium and colorectal cancer, the team was astonished to find the cancer cells present in head and neck cancers had almost been eradicated.
In the news release, Ferreira said the researchers initially expected the Fusobacterium to boost the growth of the cancers and render those cancers more resistant to treatments like radiotherapy. However, they found the opposite to be true.
“The research in colorectal cancer indicates that these bacteria are bad, and that was kind of ingrained into our minds, and we were expecting to find the same thing,” said Ferreira in a Press Association (PA) interview, The Independent reported. “When we started finding things the other way around, we were brutally surprised.”
Predicting Better Outcomes, Lower Risk of Death
“You put it in the cancer at very low quantities and it just starts killing it very quickly,” Ferreira said in the King’s College London news release. “What we’re finding is that this little bug is causing a better outcome based on something that it’s doing inside the cancer. So we are looking for that mechanism at present, and it should be the theme for a new paper in the very short-term future.”
In addition, the scientists discovered that patients with Fusobacterium within their cancer showed improved survival rates when compared to those without the bacteria. The presence of the bacteria correlated with a 65% reduction in death risk.
“What it could mean is that we can use these bacteria to better predict which patients are more likely to have good or worse outcomes, and based on that, we could change their treatment to make it kinder in the patients that have better outcomes or make it more intense in patients that are more likely to have their cancers come back,” said Ferreira in the PA interview.
“Our findings are remarkable and very surprising. We had a eureka moment when we found that our international colleagues also found data that validated the discovery,” said Anjali Chander, PhD student, senior clinical research fellow, Comprehensive Cancer Center, King’s College London, and lead author of the study in the news release.
More to Learn about Bacteria as Biomarkers
According to the National Cancer Institute (NCI), more than 71,000 people will be diagnosed with one of the major types of head and neck cancer this year in the US and more than 16,000 patients will die from these diseases.
The Global Cancer Observatory (GLOBOCAN) estimates there are about 900,000 new cases of head and neck cancers diagnosed annually worldwide with approximately 450,000 deaths attributed to those cancers every year. GLOBOCAN also claims head and neck cancers are the seventh most common cancer globally.
More research and studies are needed to confirm the virtue of this latest venture into the human microbiome. However, the preliminary results of this study appear promising.
The study of human microbiota continues to bring unexpected surprises, as scientists gain more insights and identify specific strains of bacteria that may have a positive or negative influence on an individual’s health. These discoveries may give microbiologists and clinical laboratories intriguing new biomarkers that could be incorporated into medical tests that aid diagnosis and the selection of appropriate therapies.
Predicted steady increase in the number of new cancer cases globally will stress pathologist and clinical laboratories to process specimens and issue timely cancer diagnoses to referring physicians and patients
In many nations today, it is recognized that the demand for cancer testing services outstrips the capacity of anatomic pathology laboratories to perform cancer testing in a timely manner. Now a new report published in CA, a journal of the American Cancer Society, estimates that the number of new cancers globally will increase substantially during the next few decades.
With today’s cancer diagnostic technologies and standards of practice, it is anatomic pathologists who will typically receive biopsies or patient specimens, perform the tests, and confirm/report whether a patient has cancer. Thus, this new report projecting that the disease will grow 77% to 35 million cases by the year 2050 should be of interest to pathology groups and clinical laboratories worldwide.
The report is a collaboration between the World Health Organization’s International Agency for Research on Cancer (WHO/IARC) and the American Cancer Society (ACS). The report called for “global escalation of cancer control measures” and paying close attention to risk factors such as smoking, obesity, and infections, according to an IARC statement.
Unfortunately, the news about increasing cancer cases comes at a time when worldwide demand for pathologists already far exceeds available supply.
“The impact of this increase will not be felt evenly across countries of different HDI [human development index] levels. Those who have the fewest resources to manage their cancer burdens will bear the brunt of the global cancer burden,” said epidemiology of cancer researcher Freddie Bray, PhD (above), Head of the Cancer Surveillance Branch at the IARC in Lyon, France, in a press release. Bray “specializes in estimating the global cancer burden and predicting future trends,” according to the organization’s website. He also “leads the Global Initiative for Cancer Registry Development (GICR), which is aimed at expanding the coverage and quality of population-based cancer registries in low- and middle-income countries.” Clinical laboratories and anatomic pathologists in the United States and abroad would be wise to keep an eye on the coming cancer burden. (Photo copyright: IARC.)
Top Diagnosed Cancers
To complete their study, the WHO/IARC researchers tapped GLOBOCAN [Global Cancer Observatory] estimates of cancer incidence and mortality, the disease’s geographical variability, and predictions based on global demographic projections.
The 10 most frequently diagnosed cancers for men and women (combined) by percent of cancer sites and number of new cases in 2022 include:
For women, the cancer most often diagnosed was at the breast site. It was also the leading cause of death from cancer, the CA study noted, adding that lung and colorectal cancer cases and deaths in women followed breast cancer.
For men, lung cancer was the top cancer diagnosed in terms of cases and deaths, ahead of prostate and colorectal cancer for new cases.
Geographic HDI Affects Cancer of Citizens
The geographic areas with the highest distribution of new cancer cases and mortality rates in 2022, according to the CA paper, are:
Asia: 49.2% of cases, 56.1% of deaths.
Africa: 5.9% of cases, 7.8% of deaths.
Oceania: 1.4% of cases, 0.8% of deaths.
Euro: 22.4% of cases, 20.4% of deaths.
Americas: 21.2% of cases, 14.9% of deaths.
The WHO/IARC report also associated a country’s human development index (HDI)—a measure of health, longevity, and standard of living—with the likelihood of its residents developing cancer, USA Today reported.
“From a global perspective, the risk of developing cancer tends to increase with increasing HDI level. For example, the cumulative risk of men developing cancer before age of 75 years in 2022 ranged from approximately 10% in low HDI settings to over 30% in very high HDI settings,” the researchers wrote in their CA paper.
This suggests that a lack of resources to diagnose and treat cancer can hinder response and treatment.
In a news release, the WHO pointed out examples of what it termed “striking cancer inequity by HDI.”
“Women in lower HDI countries are 50% less likely to be diagnosed with breast cancer than women in high HDI countries, yet they are at much higher risk of dying of the disease due to late diagnosis and inadequate access to quality treatment,” said medical epidemiologist Isabelle Soerjomataram, MD, PhD, Deputy Head of the Cancer Surveillance Branch, WHO/IARC, in the news release.
Additionally, lung cancer-related resources were four to seven times more likely to be offered in a high-income country than a lower-income country, the WHO noted.
“WHO’s new global survey sheds light on major inequalities and lack of financial protection for cancer around the world, with populations—especially in lower income countries—unable to access the basics of cancer care,” said Bente Mikkelsen, MD, Director of the WHO’s Department of Noncommunicable Diseases, in the news release.
Current State of Pathology Demand
Is the pathology industry prepared for a global cancer burden? Hardly.
In “Examining the Worldwide Pathologist Shortage,” Dark Daily’s sister publication The Dark Report found that demand for pathology services is growing faster than the number of pathologists available to meet that demand. This is true for the United States and most other nations. Consequently, efforts are underway to more accurately measure the number of pathologists practicing in each country. Early data support the claim of an inadequate number of pathologists.
Thus, aligning clinical laboratory and anatomic pathology resources with cancer projections is especially important in light of the WHO/IARC’s recent report which suggests the number of cancer diagnoses and different types of cancer will increase dramatically in coming years.
The data could be helpful to diagnostic leaders seeking evidence to support training of more anatomic pathologists and expansion of AP laboratories, where cancer is most often confirmed and reported.
