A husband-and-wife team at the University of Pittsburgh Cancer Institute have discovered a virus strongly linked to Merkel cell carcinoma, an aggressive skin cancer that used to be very rare but has become increasingly common in the past two decades, particularly among those with compromised immune systems.
Yuan Chang and Patrick Moore reported their findings in this week’s Science.
Interestingly, Merkel cell polyomavirus (MCV) is the second cancer-associated virus discovered by the pair. In 1993, they found the virus that causes the most common cancer in Africa, Kaposi’s sarcoma.
Chang and Moore spent nearly a decade developing a new technology that was instrumental in discovering the virus. “Digital transcriptome subtraction” is so called because it subtracts genetic sequences known to be human from the genome of the tumor under study, leaving only genetic transcripts that might have come from a foreign organism.
Using the technique in Merkel cell tumors, they found one sequence that was similar to, but distinct from, known viruses. They went on to show that this sequence belonged to a new polyomavirus that was present in almost all the Merkel cell tumors they tested, but few other tissues.
Their discovery could lead to a blood test or vaccine, similar to the recently developed vaccines against human papillomavirus (HPV) to prevent cervical cancer.
Researchers had suspected the existence of MCV, which is genetically similar to an African green monkey virus. Up to a quarter of adults–one billion people–could be infected with the human relative of this monkey virus. However, just as with HPV, most people with the virus will not develop the associated cancer.