Wednesday, November 15, 2017 -- Purpose: To validate the prognostic impact of combined expression levels of three markers (SPP1, RGS1, and NCOA3) in melanoma specimens from patients enrolled in the E1690 clinical trial of high-dose or low-dose IFNα-2b versus observation. Experimental Design: Tissue was available from 248 patients. Marker expression was determined by digital imaging of immunohistochemically stained slides. The prognostic impact of each marker was first assessed by recording its expression value relative to the median. A multimarker index was then developed to combine marker expression levels by counting for each patient the number of markers with high expression. The impact of the multimarker index on relapse-free survival (RFS) and overall survival (OS) was assessed using Kaplan–Meier analysis, and both univariate and multivariate
Wednesday, November 15, 2017 -- Purpose: Effective therapies for the majority of metastatic acral melanoma patients have not been established. Thus, we investigated genetic aberrations of CDK4 pathway in acral melanoma and evaluated the efficacy of CDK4/6 inhibitors in targeted therapy of acral melanoma. Experimental Design: A total of 514 primary acral melanoma samples were examined for the copy number variations (CNV) of CDK4 pathway-related genes, including Cdk4, Ccnd1, and P16INK4a, by QuantiGenePlex DNA Assay. The sensitivity of established acral melanoma cell lines and patient-derived xenograft (PDX) containing typical CDK4 aberrations to CDK4/6 inhibitors was evaluated. Results: Among the 514 samples, 203 cases, 137 cases, and 310 cases, respectively, showed Cdk4 gain (39.5%), Ccnd1 gain (26.7%), and P16INK4a loss (60.3%). The overall frequency of
Wednesday, November 15, 2017 -- Purpose: Understanding tumor heterogeneity is an important challenge in current cancer research. Transcription and epigenetic profiling of cultured melanoma cells have defined at least two distinct cell phenotypes characterized by distinctive gene expression signatures associated with high or low/absent expression of microphthalmia-associated transcription factor (MITF). Nevertheless, heterogeneity of cell populations and gene expression in primary human tumors is much less well characterized. Experimental Design: We performed single-cell gene expression analyses on 472 cells isolated from needle biopsies of 5 primary human melanomas, 4 superficial spreading, and one acral melanoma. The expression of MITF-high and MITF-low signature genes was assessed and compared to investigate intra- and intertumoral heterogeneity and correlated gene expression profiles. Results: Single-cell gene expression analyses revealed varying
Wednesday, November 15, 2017 -- For the first time Queensland researchers have found that incidence rates for invasive melanomas have started to stabilize or fall in those aged under 60 years, a groundbreaking new study shows.