Establishment and characterization of two uveal melanoma cell lines derived from tumors with loss of one chromosome 3.

Uveal melanoma (UM) is the most common intraocular malignancy. Approximately 50% of UM patients die of metastases, which mainly arise from primary tumors with loss of an entire chromosome 3 (monosomy 3). To identify cell lines with monosomy 3 that may serve as a model system for UM with high metastatic potential, we determined the chromosome 3 status of previously established and frequently used UM cell lines by microsatellite analysis (Mel202, Mel285, Mel290, 92-1, OMM-1, OCM-1, OCM-3, OCM-8) and cytogenetic analysis (Mel202, Mel285, OCM-8). We found that none of these cell lines has monosomy 3. Therefore we established and characterized two novel cell lines, UPMM-1 and UPMM-2 that are both developed from primary uveal melanoma tissue samples with monosomy 3. The cell line UPMM-1 has retained the chromosome 3 status of the primary tumor. In UPMM-2 chromosome 3 has undergone duplication (isodisomy) and is present on the background of a hypotetraploid karyotype. Our data suggest that, UPMM-1 may serve as a model system to study the mechanisms underlying the metastatic potential of uveal melanomas with monosomy 3.