Diagnosis and treatment of Merkel cell polyomavirus

Background and Aim : Merkel cell polyomavirus (MCPyV) causes a very aggressive andrelatively rare skin cancer called Merkel cell carcinoma (MCC). Diagnosis of the virus is still at aresearch phase and is generally not available as a clinical test. Diagnosis of viral DNA is performedusing PCR or by Southern blot. Care should be taken when interpreting PCR results, as PCR resultsare susceptible to false-positive contamination and a significant proportion of healthy skin samplescan indicate low levels of infection.Methods : Antibodies have been developed to stain T antigens in tumor tissues and seems to bespecific for MCV-infected tumor cells. Blood tests have also been developed which suggest thatthe majority of adults have been exposed to MCV and may continue to carry it as an asymptomaticinfection. Treatment guidelines are not different for Merkel cell carcinoma with or without MCV.Results : A recent nationwide study in Finland found that MCV-positive tumors had a betterprognosis than uninfected tumors. If confirmed, routine virus detection could benefit futuremedical guidance. The virus itself is not known to be susceptible to current antiviral drugs.Conclusion : Recent studies suggest that survivin oncoproteins activated by MCV large T proteinsthat target retinoblastoma proteins and that survivin inhibitors can delay tumor progression onanimal model. MCVs are targets for cell-mediated immune responses, and therefore importantresearch efforts focus on immunotherapies that may benefit MCC patients.

کلیدواژه ها:

Merkel cell polyomavirus (MCPyV) ، Merkel cell carcinoma (MCC) ، T antigens ، survivin oncoproteins ، immunotherapies