Genetic profiling of rat gliomas and cardiac schwannomas from life-time
radiofrequency radiation exposure study using a targeted next-generation
sequencing gene panel
Brooks AM, Vornoli A, Kovi RC, Ton TVT, Xu M, Mashal A, Tibaldi E, Gnudi
F, Li JL, Sills RC, Bucher JR, Mandrioli D, Belpoggi F, Pandiri AR.
Genetic profiling of rat gliomas and cardiac schwannomas from life-time
radiofrequency radiation exposure study using a targeted next-generation
sequencing gene panel. PLoS One. 2024 Jan 17;19(1):e0296699. doi:
10.1371/journal.pone.0296699.
Abstract
The cancer hazard associated with lifetime exposure to radiofrequency radiation (RFR) was examined in Sprague Dawley (SD) rats at the Ramazzini Institute (RI), Italy. There were increased incidences of gliomas and cardiac schwannomas. The translational relevance of these rare rat tumors for human disease is poorly understood. We examined the genetic alterations in RFR-derived rat tumors through molecular characterization of important cancer genes relevant for human gliomagenesis. A targeted next-generation sequencing (NGS) panel was designed for rats based on the top 23 orthologous human glioma-related genes. Single-nucleotide variants (SNVs) and small insertion and deletions (indels) were characterized in the rat gliomas and cardiac schwannomas. Translational relevance of these genetic alterations in rat tumors to human disease was determined through comparison with the Catalogue of Somatic Mutations in Cancer (COSMIC) database. These data suggest that rat gliomas resulting from life-time exposure to RFR histologically resemble low grade human gliomas but surprisingly no mutations were detected in rat gliomas that had homology to the human IDH1 p.R132 or IDH2 p.R172 suggesting that rat gliomas are primarily wild-type for IDH hotspot mutations implicated in human gliomas. The rat gliomas appear to share some genetic alterations with IDH1 wildtype human gliomas and rat cardiac schwannomas also harbor mutations in some of the queried cancer genes. These data demonstrate that targeted NGS panels based on tumor specific orthologous human cancer driver genes are an important tool to examine the translational relevance of rodent tumors resulting from chronic/life-time rodent bioassays.
Excerpt
In summary, our results demonstrate that regardless of their etiology (due to lifetime RFR exposure or arising spontaneously), rat gliomas are primarily Idh1/2 wild type unlike most human gliomas. Histologically, most of the rat gliomas resemble diffuse low-grade gliomas in humans and such gliomas that do not harbor IDH1/2 mutations in humans are known to have poor prognosis. The genetic alterations in other cancer genes evaluated in this panel provide novel insights into tumor progression in rat gliomas and cardiac schwannomas. The relevance of specific mutations to human cancers is variable, with some genes (Tp53, Cdkn2a, Erbb2, Chek2, Kras and Pik3r1) harboring many alterations with COSMIC relevance while the opposite is true for other target genes (Idh1/2, Atrx, Notch1, Pten, Rb1 and Setd2). Several of these conserved mutations in rat tumors do not have comparable alterations in the COSMIC database, suggesting that the orthologous mutations could have different functional consequences in rat carcinogenesis and deserve further study. An important consideration is that molecular differences underlying mutational processes contribute to distinct mutational patterns which could be the result of similar etiology, albeit by different mechanisms.
Several of the variants that were detected in gliomas were also observed in non-tumor brain tissues from interim time point providing an insight into the molecular pathogenesis in rodent carcinogenicity studies and these strategies may be utilized to potentially estimate the cancer hazard risk in shorter term animal studies. Finally, this targeted mutation panel may be refined using data from whole genome or exome sequencing of rat tumors and performing error corrected duplex sequencing to increase the sensitivity to detect rare mutations in exposed non-tumor tissues from early time points.
Open access paper:
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March 22, 2018
The Ramazzini Institute (RI) conducted a life-span study on
rats to evaluate the carcinogenic effects of cell phone radiation.
Among male rats, the overall incidence of heart schwannoma and hyperplasia (precancerous cells) was 0.7% (3 of 412) in the control group, 1.2% (5/401) in the 5 volts/meter (V/m) group, 1.0% (2/209) in the 25 V/m group, and 3.9% (8/207) in the 50 V/m group. The 50 V/m group had significantly greater incidence than the control group (p < .02).
Among male rats, the overall incidence of glioma and glial cell hyperplasia in the control group was 0.0% (0 of 412), 0.7% (3/401) in the 5 V/m group, 1.4% (3/209) in the 25 V/m group, and 0.0% (0/207) in the 50 V/m group. However, these differences were not statistically significant.
Among male rats, the overall incidence of heart schwannoma and hyperplasia (precancerous cells) was 0.7% (3 of 412) in the control group, 1.2% (5/401) in the 5 volts/meter (V/m) group, 1.0% (2/209) in the 25 V/m group, and 3.9% (8/207) in the 50 V/m group. The 50 V/m group had significantly greater incidence than the control group (p < .02).
Among male rats, the overall incidence of glioma and glial cell hyperplasia in the control group was 0.0% (0 of 412), 0.7% (3/401) in the 5 V/m group, 1.4% (3/209) in the 25 V/m group, and 0.0% (0/207) in the 50 V/m group. However, these differences were not statistically significant.
The study used a different GSM cell phone carrier
frequency (1800 MHz vs. 900 MHz) and much lower intensity microwave radiation
exposures than the NTP study. The Specific Absorption Rates ranged from 0.001 -
0.1 W/kg SAR in the RI study as compared to 1.5 - 6.0 W/kg in the NTP study.
The Ramazzini Institute is a non-profit organization in
Bologna, Italy that has conducted scientific research for more than
two decades to identify and quantify environmental toxic and carcinogenic risks
and evaluate the effectiveness of drugs to prevent the onset or development of
cancer.
The abstract for the paper and the press release appear below.
P.S. In our six-nation study of RFR exposure, the average total RFR exposure (not just cell tower RFR) was highest in Los Angeles where it ranged from 0.72 to 1.60 V/m across eight different outdoor microenvironments (Sagar et al., 2018). The highest average total RFR value measured in our study was 1.85 V/m which was found on a university campus in Australia and was attributable to FM radio transmissions.
The abstract for the paper and the press release appear below.
P.S. In our six-nation study of RFR exposure, the average total RFR exposure (not just cell tower RFR) was highest in Los Angeles where it ranged from 0.72 to 1.60 V/m across eight different outdoor microenvironments (Sagar et al., 2018). The highest average total RFR value measured in our study was 1.85 V/m which was found on a university campus in Australia and was attributable to FM radio transmissions.
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Falcioni L, Bua L, Tibaldi E, et al. Report of final results regarding brain and heart tumors in Sprague-Dawley rats exposed from prenatal life until natural death to mobile phone radiofrequency field representative of a 1.8 GHz GSM base station environmental emission. Environ Res. 2018;165:496-503. doi:10.1016/j.envres.2018.01.037
Abstract
Background: In 2011, IARC (International Agency for Research on Cancer) classified radiofrequency radiation (RFR) as possible human carcinogen (Group 2B). According to IARC, animals studies, as well as epidemiological ones, showed limited evidence of carcinogenicity. In 2016, the NTP published the first results of its long-term bioassays on near field RFR, reporting increased incidence of malignant glial tumors of the brain and heart Schwannoma in rats exposed to GSM – and CDMA –modulated cell phone RFR. The tumors observed in the NTP study are of the type similar to the ones observed in some epidemiological studies of cell phone users.
Background: In 2011, IARC (International Agency for Research on Cancer) classified radiofrequency radiation (RFR) as possible human carcinogen (Group 2B). According to IARC, animals studies, as well as epidemiological ones, showed limited evidence of carcinogenicity. In 2016, the NTP published the first results of its long-term bioassays on near field RFR, reporting increased incidence of malignant glial tumors of the brain and heart Schwannoma in rats exposed to GSM – and CDMA –modulated cell phone RFR. The tumors observed in the NTP study are of the type similar to the ones observed in some epidemiological studies of cell phone users.
Objectives: The Ramazzini Institute (RI) performed a life-span carcinogenic study on Sprague-Dawley rats to evaluate the carcinogenic effects of RFR in the situation of far field, reproducing the environmental exposure to RFR generated by 1.8 GHz GSM antenna of the radio base stations of mobile phone. This is the largest long-term study ever performed in rats on the health effects of RFR, including 2448 animals. In this article, we reported the final results regarding brain and heart tumors.
Methods: Male and female Sprague-Dawley rats were exposed from prenatal life until natural death to a 1.8 GHz GSM far field of 0, 5, 25, 50 V/m with a whole-body exposure for 19 h/day.
Results: A statistically significant increase in the incidence of heart Schwannomas was observed in treated male rats at the highest dose (50 V/m). Furthermore, an increase in the incidence of heart Schwann cells hyperplasia was observed in treated male and female rats at the highest dose (50 V/m), although this was not statistically significant. An increase in the incidence of malignant glial tumors was observed in treated female rats at the highest dose (50 V/m), although not statistically significant.
Conclusions: The RI findings on far field exposure to RFR are consistent with and reinforce the results of the NTP study on near field exposure, as both reported an increase in the incidence of tumors of the brain and heart in RFR-exposed Sprague-Dawley rats. These tumors are of the same histotype of those observed in some epidemiological studies on cell phone users. These experimental studies provide sufficient evidence to call for the reevaluation of IARC conclusions regarding the carcinogenic potential of RFR in humans.
https://pubmed.ncbi.nlm.nih.gov/29530389/
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Title: World’s Largest Animal Study on Cell Tower Radiation Confirms Cancer Link
Environmental Health Trust, Press Release, March 22, 2018
Byline: Scientists call on the World Health Organization International Agency for the Research on Cancer to re-evaluate the carcinogenicity of cell phone radiation after the Ramazzini Institute and US government studies report finding the same unusual cancers.
(Washington, DC) – Researchers with the renowned Ramazzini Institute (RI) in Italy announce that a large-scale lifetime study of lab animals exposed to environmental levels of cell tower radiation developed cancer. A $25 million study of much higher levels of cell phone radiofrequency (RF) radiation, from the U.S. National Toxicology Program (NTP) has also reported finding the same unusual cancer called Schwannoma of the heart in male rats treated at the highest dose. In addition, the RI study of cell tower radiation also found increases in malignant brain (glial) tumors in female rats and precancerous conditions including Schwann cell hyperplasia in both male and female rats.
"Our findings of cancerous tumors in rats exposed to environmental levels of RF are consistent with and reinforce the results of the US NTP studies on cell phone radiation, as both reported increases in the same types of tumors of the brain and heart in Sprague-Dawley rats. Together, these studies provide sufficient evidence to call for the International Agency for Research on Cancer (IARC) to re-evaluate and re-classify their conclusions regarding the carcinogenic potential of RFR in humans," said Fiorella Belpoggi PhD, study author and RI Director of Research.
The Ramazzini study exposed 2448 Sprague-Dawley rats from prenatal life until their natural death to “environmental” cell tower radiation for 19 hours a day (1.8 GHz GSM radio frequency radiation (RFR) of 5, 25 and 50 V/m). RI exposures mimicked base station emissions like those from cell tower antennas, and exposure levels were far less than those used in the NTP studies of cell phone radiation.
“All of the exposures used in the Ramazzini study were below the US FCC limits. These are permissible exposures according to the FCC. In other words, a person can legally be exposed to this level of radiation. Yet cancers occurred in these animals at these legally permitted levels. The Ramazzini findings are consistent with the NTP study demonstrating these effects are a reproducible finding,” explained Ronald Melnick PhD, formerly the Senior NIH toxicologist who led the design of the NTP study on cell phone radiation. “Governments need to strengthen regulations to protect the public from these harmful non-thermal exposures.”
“This important article from one of the most acclaimed institutions of its kind in the world provides a major new addition to the technical literature indicating strong reasons for concern about electromagnetic radiation from base stations or cell towers,” stated Editor in Chief of Environmental Research Jose Domingo PhD, Professor of Toxicology, School of Medicine at Reus University, Catalonia, Spain.
“The US NTP results combined now with the Ramazzini study, reinforce human studies from our team and others providing clear evidence that RF radiation causes acoustic neuroma (vestibular schwannoma) and gliomas, and should be classified carcinogenic to humans,” stated Lennart Hardell MD, PhD, physician-epidemiologist with the Department of Oncology, University Hospital, Örebro, Sweden who has published extensively on environmental causes of cancer including Agent Orange, pesticides and cell phone radiofrequency radiation.
“The evidence indicating wireless is carcinogenic has increased and can no longer be ignored,” stated University of Toronto Dalla Lana School of Public Health Professor Emeritus Anthony B. Miller MD, Member of the Royal Colleges of Physicians of Canada and the UK, who is also a long-term adviser to the World Health Organization.
“This study raises concerns that simply living close to a cell tower will pose threats to human health. Governments need to take measures to reduce exposures from cell tower emissions. Cell towers should not be near schools, hospitals or people's homes. Public health agencies need to educate the public on how to reduce exposure from all sources of wireless radiofrequency radiation--be it from cell towers or cell phones or Wi-Fi in schools, " stated David O. Carpenter MD, former Dean of the School of Public Health at the University at Albany. “This is particularly urgent because of current plans to place small 5G cell towers about every 300 meters in every street across the country. These 5G “small cell’ antennas will result in continuous exposure to everyone living nearby and everyone walking down the street. The increased exposures will increase risk of cancer and other diseases such as electro-hypersensitivity.”
Ramazzini Institute investigators have completed nearly 500 cancer bioassays on more than 200 compounds, and their study design is unique in that animals are allowed to live until their natural deaths in order to allow detection of late-developing tumors. Eighty percent of all human cancers are late-developing, occurring in humans after 60 years of age. This longer observation period has allowed the RI to detect such later-occurring tumors for a number of chemicals, and their published research includes studies of benzene, xylenes, mancozeb, formaldehyde, and vinyl chloride.
The Ramazzini research results come in the wake of similar findings from the US National Toxicology Program (NTP) large-scale experimental studies on cell phone radiation. Both studies found statistically significant increases in the development of the same type of very rare and highly malignant tumor in the heart of male rats—schwannomas.
“This publication is a serious cause for concern, “ stated Annie J. Sasco, MD, DrPH, SM, MPH, retired Director of Research at the INSERM (French NIH) and former Unit Chief at International Agency for the Research on Cancer/World Health Organization, France who commented that, “some of the results are not statistically significant due to the relatively small number of animals involved. Yet, that does not mean they should be ignored. Larger studies could turn out statistically significant results and in any event statistical significance is just one aspect of evaluation of the relation between exposure and disease. Biological significance and concordance of results between humans and animals clearly reinforces the strength of the evidence of carcinogenicity. The facts that both experimental studies found the same types of rare tumors, which also have pertinence to the human clinical picture, is striking,”
“Such findings of effects at very low levels are not unexpected,” stated Devra Davis PhD, MPH, president of Environmental Health Trust (EHT), pointing to a Jacobs University replication animal study published in 2015 that also found very low levels of RFR promoted tumor growth.“This study confirms an ever growing literature and provides a wake-up call to governments to enact protective policy to limit exposures to the public and to the the private sector to make safe radiation-free technology available.”
In January 2017 at an international conference co-sponsored by EHT and the Israel Institute for Advanced Study at Hebrew University, Fiorella Belpoggi PhD, Director of Research at the Ramazzini Institute, presented the study design and the findings that RFR-exposed animals had significantly lower litter weights. Belpoggi’s presentation and slides are available online. The Ramazzini findings of lower litter weights are consistent with the NTP study, which also found lower litter weights in prenatally exposed animals. At that time, the Italian journal Corriere published an article about the presentation of the Ramazzini study and quoted Belpoggi’s recommendation of “maximum precaution for children and pregnant women.”
Noting that “current standards were not set to protect children, pregnant women, and the growing numbers of infants and toddlers for whom devices have become playthings”, Davis, who is also Visiting Professor of Medicine of Hebrew University Medical Center, and Guest Editor in Chief of the journal Environmental Research, added, “Current two-decade old FCC limits were set when the average call was six minutes and costly cell phones were used by very few. These important, new, game-changing studies show that animals develop the same types of unusual cancers that are being seen in those few human epidemiological studies that have been done. In light of these results, EHT joins with public health experts from the states of California, Connecticut and Maryland, as well as those in France, Israel, and Belgium to call on government and the private sector to carry out major ongoing public health educational campaigns to promote safer phone and personal device technology, to require and expedite fundamental changes in hardware and software to reduce exposures to RFR/microwave radiation throughout indoor and outdoor environments, and to institute major monitoring, training and research programs to identify solutions, future problems and prevention of related hazards and risks.”
“More than a dozen countries recommend reducing radiofrequency radiation exposure to children, and countries such as China, Italy, India and Russia have far more stringent cell tower radiation regulations in place when compared to the United States. However, this study provides scientific evidence that governments can use to take even further action,” stated Theodora Scarato, Executive Director of EHT.
The article is “Report of final results regarding brain and heart tumors in Sprague-Dawley rats exposed from prenatal life until natural death to mobile phone radiofrequency field representative of a 1.8 GHz base station environmental emission” by L. Falcioni, L. Bua, E.Tibaldi, M. Lauriola, L. De Angelis, F. Gnudi, D. Mandrioli, M. Manservigi, F. Manservisi, I. Manzoli, I. Menghetti, R. Montella, S. Panzacchi, D. Sgargi, V. Strollo, A.Vornoli, F. Belpoggi (doi.org/10.1016/j.envres.
