Bovine Meat and Milk Factors
{{Short description|DNA molecules linked to cancer}}
{{Expert needed|1=Medicine|reason=Medical-related|date=March 2021}}
Bovine Meat and Milk Factors (BMMFs) are circular, single-stranded DNA molecules (cssDNAs) originally found in beef and cow's milk which have been linked to the development of cancer—particularly colorectal and breast cancer.{{Cite web|title=Episomal-Persistent DNA in Cancer- and Chronic Diseases|url=https://www.dkfz.de/en/episomal-persistierende-DNA/groups/Research.html|access-date=2021-03-03|website=Deutsches Krebsforschungszentrum}} They are formerly known as Slow Progressive Hidden INfections of variable X (SPHINX). Similar molecules have since been found in a much wider range of food.{{cite journal |last1=Pohl |first1=Sina |last2=Habermann |first2=Diana |last3=Link |first3=Ellen K. |last4=Fux |first4=Robert |last5=Boldt |first5=Christine L. |last6=Franz |first6=Charles M.A.P. |last7=Hölzel |first7=Christina |last8=Klempt |first8=Martin |title=Detection of DNA sequences attributed to bovine meat and milk factors (BMMF/SPHINX) in food-related samples |journal=Food Control |date=May 2022 |volume=135 |pages=108779 |doi=10.1016/j.foodcont.2021.108779}}
BMMF/SPHINX sequences are able to copy themselves in animal cells. They encode functional proteins that are expressed in some animal cells. Every BMMF/SPHINX contains at least a "Rep" open reading frame, which encodes a replication endonuclease that, in HEK 239TT cells, acts to replicate and retain the cssDNA.{{cite journal |last1=Dhurve |first1=G |last2=Behera |first2=SR |last3=Kodetham |first3=G |last4=Siddavattam |first4=D |title=Outer membrane vesicles of Acinetobacter baumannii DS002 carry circular DNA similar to bovine meat and milk factors (BMMFs) and SPHINX 2.36 and probably play a role in interdomain lateral gene transfer. |journal=Microbiology Spectrum |date=3 September 2024 |volume=12 |issue=9 |pages=e0081724 |doi=10.1128/spectrum.00817-24 |pmid=39101807|pmc=11370262 }}
BMMF/SPHINX sequences are divided into four clades. Clades 1, 2, and 3 share sequence similarity with the plasmids of Acinetobacter baumannii. (A. baumanii regularly produces outer membrane vesicles containing these plamids, and animal cells are known to take up these vesicles.) Clade 4 shares sequence similarity with Gemycircularvirus.
Health research
The potential connection between BMMFs and cancer has been made based on assessments of epidemiological data{{Cite journal|last1=Hausen|first1=Harald zur|last2=Villiers|first2=Ethel-Michele de|date=2015|title=Dairy cattle serum and milk factors contributing to the risk of colon and breast cancers |journal=International Journal of Cancer|language=en|volume=137|issue=4|pages=959–67 |doi=10.1002/ijc.29466|pmid=25648405|s2cid=34785153|issn=1097-0215|doi-access=free}}{{Cite journal|last1=Hausen|first1=Harald zur|last2=Bund|first2=Timo|last3=Villiers|first3=Ethel-Michele de|date=2019|title=Specific nutritional infections early in life as risk factors for human colon and breast cancers several decades later|journal=International Journal of Cancer|language=en|volume=144|issue=7|pages=1574–1583|doi=10.1002/ijc.31882|pmid=30246328|s2cid=52348195|issn=1097-0215|doi-access=free}}{{Cite news|last=Däuble|first=Wolfgang|title=Nobelpreisträger zur Hausen: Warum haben Inder so selten Darmkrebs?|language=de|trans-title=Nobel laureate zur Hausen: Why do Indians so rarely have colon cancer?|work=FAZ.NET|url=https://www.faz.net/1.2904246|access-date=2021-03-03|issn=0174-4909}} and the investigation of antibodies in human serum.{{Cite journal|last1=Eilebrecht|first1=Sebastian|last2=Hotz-Wagenblatt|first2=Agnes|last3=Sarachaga|first3=Victor|last4=Burk|first4=Amelie|last5=Falida |first5=Konstantina|last6=Chakraborty|first6=Deblina|last7=Nikitina|first7=Ekaterina|last8=Tessmer|first8=Claudia|last9=Whitley|first9=Corinna|last10=Sauerland|first10=Charlotte|last11=Gunst|first11=Karin|date=2018-02-12|title=Expression and replication of virus-like circular DNA in human cells|journal=Scientific Reports|language=en|volume=8|issue=1|pages=2851|doi=10.1038/s41598-018-21317-w|pmid=29434270|pmc=5809378|bibcode=2018NatSR...8.2851E|issn=2045-2322|doi-access=free}}{{Cite web|title=Erhöhtes Krebsrisiko durch Kuhmilch und Rindfleisch?|trans-title=Increased cancer risk from cow's milk and beef?|url=https://www.aerztezeitung.de/Medizin/Erhoehtes-Krebsrisiko-durch-Kuhmilch-und-Rindfleisch-224843.html|access-date=2021-03-03|website=AerzteZeitung.de|date=23 October 2018 |language=de}} Research has also suggested a potential link between BMMFs and neurodegenerative diseases such as multiple sclerosis.
At the end of 2017, evidence was presented that BMMFs in human cells show long-term survival, through the identification of BMMFs' RNA and protein products.{{Cite web|title=Episomal-Persistierende DNA in Krebs- und chronischen Erkrankungen|url=https://www.dkfz.de/de/episomal-persistierende-DNA/index.php|access-date=2021-03-03|website=Deutsches Krebsforschungszentrum}} In February 2019, evidence was presented of a previously unknown infectious agent in the blood serum and milk of Eurasian cattle that could indirectly trigger the development of colorectal cancer.
References
Further reading
- {{Cite thesis|last=Falida|first=Konstantina|title=Identification of single-stranded DNAs from beef products, their replication in human cells and their relationship with breast cancer|date=2019-12-11|publisher=Heidelberg University|url=https://archiv.ub.uni-heidelberg.de/volltextserver/27574/|degree=DSc}}