MelanA-negative spindle-cell associated melanoma, a distinct inflammatory phenotype correlated with dense infiltration of CD163 macrophages and loss of E-cadherin.

MelanA is a known melanocyte marker and is important in melanoma diagnostics. Some tumours, however, show loss of MelanA expression and may therefore be difficult to distinguish from tumours of mesenchymal origin. Pure spindle-cell melanoma is a rare event, and little is known about its biological background and prognosis. However, morphological changes towards a more mesenchymal shape and cellular dedifferentiation may correlate with reactivation of important developmental programmes (epithelial-to-mesenchymal transition) and disseminative tumour cell properties. Inflammation and CD163+ macrophages have been shown to be important inducers of E-cadherin and cell-to-cell adhesion loss, a pivotal and final event of epithelial-to-mesenchymal transition. In a cohort of 385 patients with melanoma, we located nine tumours with a clonal MelanA expression, defined as a tumour section with a distinct MelanA-negative clone next to a MelanA-positive clone. Interestingly, MelanA-negative clones correlated significantly with an augmented inflammatory response of tumour-infiltrating macrophages (CD163+), complete loss of E-cadherin and a spindle-shaped morphology, irrespective of ulcerated status. These cases show the inflammatory heterogeneity of melanoma, which may have important diagnostic, prognostic and therapeutic implications for the patients. We show that melanomas harbour cell clones that bear strong resemblance to tumour-associated macrophages, a pivotal player in a tumour-supporting microenvironment. Interestingly, this distinct inflammatory phenotype is associated with loss of MelanA expression, the presence of spindle-shape morphology and complete loss of E-cadherin, considered as possible markers of poorly differentiated and more invasive tumour cells.

Prognostic stratification of ulcerated melanoma: not only the extent matters.

OBJECTIVES: For patients with melanoma, ulceration is an important prognostic marker and interestingly also a predictive marker for the response of adjuvant interferon. A consensual definition and accurate assessment of ulceration are therefore crucial for proper staging and clinical management. We evaluated the prognostic impact of the extent and type of ulceration and the epidermal involvement theoretically preceding it (consumption of epidermis and cleft formation) or seen subsequent to the inflammation (reepithelialization and reactive epidermal hyperplasia), aiming for better prognostic stratification of ulcerated lesions. METHODS: From H&E-stained sections, the status (presence vs absence), extent (percentage of the total tumor length), and type (infiltrative vs attenuative) of ulceration and epidermal involvement were evaluated from 385 patients with cutaneous melanoma. RESULTS: The presence of ulceration (hazard ratio [HR], 1.83), an attenuative type of ulceration (HR, 3.02), and excessive ulceration (HR, 3.57) were independent predictors of poor melanoma-specific survival. Further subdivision of minimal/moderate ulceration showed independent prognostic value only for lesions with epidermal involvement of the surrounding epidermis (HR, 1.78). CONCLUSION: The extent and type of ulceration and involvement of the surrounding epidermis provided more accurate prognostic information than the mere absence or presence and may be useful markers allowing better stratification of ulcerated lesions.

Mammary tumors initiated by constitutive Cdk2 activation contain an invasive basal-like component.

The basal-like subtype of breast cancer is associated with invasiveness, high rates of postsurgical recurrence, and poor prognosis. Aside from inactivation of the BRCA1 tumor-suppressor gene, little is known concerning the mechanisms that cause basal breast cancer or the mechanisms responsible for its invasiveness. Here, we show that the heterogeneous mouse mammary tumor virus-cyclin D1-Cdk2 (MMTV-D1K2) transgenic mouse mammary tumors contain regions of spindle-shaped cells expressing both luminal and myoepithelial markers. Cell lines cultured from these tumors exhibit the same luminal/myoepithelial mixed-lineage phenotype that is associated with human basal-like breast cancer and express a number of myoepithelial markers including cytokeratin 14, P-cadherin, alpha smooth muscle actin, and nestin. The MMTV-D1K2 tumor-derived cell lines form highly invasive tumors when injected into mouse mammary glands. Invasion is associated with E-cadherin localization to the cytoplasm or loss of E-cadherin expression. Cytoplasmic E-cadherin correlates with lack of colony formation in vitro and beta-catenin and p120(ctn) localization to the cytoplasm. The data suggest that the invasiveness of these cell lines results from a combination of factors including mislocalization of E-cadherin, beta-catenin, and p120(ctn) to the cytoplasm. Nestin expression and E-cadherin mislocalization were also observed in human basal-like breast cancer cell lines, suggesting that these results are relevant to human tumors. Together, these results suggest that abnormal Cdk2 activation may contribute to the formation of basal-like breast cancers.

Serum YKL-40 concentrations in newly diagnosed multiple myeloma patients and YKL-40 expression in malignant plasma cells.

OBJECTIVES: A potential role in cancer biology is suggested for YKL-40 (CHI3L1, HC gp-39). The purpose of this study was to evaluate the clinical value of serum YKL-40 (sYKL-40) in multiple myeloma (MM) and to examine YKL-40 expression in malignant plasma cells (MM PCs). METHODS: sYKL-40 was measured by enzyme-linked immunosorbent assay (ELISA) in 82 patients with newly diagnosed MM. YKL-40 expression in immunophenotypically defined plasma cells was investigated by double-labelled immunohistochemistry in 21 MM patients and by real-time reverse transcriptase polymerase chain reaction (RT-PCR) in cDNA archives generated by global RT-PCR in seven controls, 14 patients with monoclonal gammopathy of undetermined significance (MGUS), 45 MM patients, nine patients with extramedullary myeloma (exMM), and seven human myeloma cell lines (HMCLs). RESULTS: sYKL-40 was elevated above a constructed reference range for healthy controls in 29% of the patients investigated. Patients with elevated sYKL-40 had reduced overall survival and event-free survival when compared to patients with normal sYKL-40, but sYKL-40 level was defeated by beta(2)-microglobulin in the multivariate analyses. Intramedullary MM PCs lacked significant expression of YKL-40, but high levels of YKL-40 expression were seen in extramedullary MM PCs from one exMM patient and in six HMCLs. Further investigations of other bone marrow (BM) cells showed YKL-40 expression in megakaryocytes, neutrophils and adherent cells from long-term BM cultures. CONCLUSIONS: In newly diagnosed MM-patients, a sYKL-40 elevated above the reference range predicts a poor clinical outcome, and YKL-40 is expressed by other BM cells than MM PCs. At this point, routine measurements of sYKL-40 are not warranted, but YKL-40 should be considered as a potential player in the pathophysiology of MM.