Background

Merkel cell carcinoma (MCC) is a very rare, but highly aggressive neuroendocrine skin cancer that is attributed to the Merkel cell polyomavirus in 80% of cases. It has an incidence rate of 2,000 cases per year with a two-year mortality rate of 40%. Many cancers present with decreased expression of major histocompatibility complex class I (MHC-I), leading to cancer cell evasion of immune system recognition through a common target known as human leukocyte antigen class 1 (HLA 1). HLA 1 expression is reduced in MCC, as well as many other cancers. Therefore, increasing levels of MHC-1 molecules, such as HLA 1, may serve as a mechanism of improving immune system detection of tumors.