Establishing an immune gene signature for stage II cutaneous melanoma at high risk of recurrence

Melanoma is a devastating form of skin cancer that is rarely curative in advanced stages of the disease. Even early stage melanomas can metastasize and accurate diagnosis and clinical staging is vitally important. Evidence shows that the host immune system plays a determinative role in clinical outcomes in cancer. Studies in liver cancer, lung cancer, prostate cancer, and advanced melanoma have revealed that the expression of inflammatory genes by "normal" host cells correlates with survival. Prognostic information in cancer can therefore be learned from study of the host immunologic milieu. Characterization of the immune signature of melanoma is clearly an important step in disease staging, prognostication, and therapeutics. Primary melanomas have been inadequately studied to date because clinical standards require that the entire specimen be fixed in formalin to preserve morphology for pathology diagnosis. This process is damaging to RNA, hindering analysis of gene expression signatures. Novel technologies recently developed, however, allow for analysis of partially degraded RNA derived from formalin fixed paraffin embedded (FFPE) tissue blocks. Pure RNA extracted from these FFPE tissue blocks can be analyzed using an nCounter system (NanoString) which is capable of detecting as little as 0.5 fM of a specific mRNA. This has opened a new avenue for high throughput research in this area. In this study we propose to use such cutting-edge technologies to create a gene signature for recurrent melanoma. Specifically in this study we have three aims: screen the dermatopathology database at Mount Sinai and identify melanoma specimens from patients who subsequently recurred and matched specimens from patients who did not recur; establish a protocol for extraction of RNA from paraffin embedded primary melanoma tissues; and establish an inflammatory signature for early stage melanoma at high risk of recurrence. We believe that characterization of the immune signature of melanoma is clearly an important step in disease staging, prognostication, and therapeutics of this devastating disease.