PLEC and melanoma: For example, an abnormal enrichment of plectin-positive spindle stromal cells has been observed in the bone marrow of acute myeloid leukemia (AML) patients [37]; glioblastoma multiforme (GBM) cell lines exhibit higher levels of surface plectin microdomains compared to normal astrocytes [48]; and plectin is upregulated in human primary melanoma samples relative to normal melanocytes [29].