A novel human malignant fibrous histiocytoma cell line of the heart (MFH-H) with secretion of hematopoietic growth factors.

Primary malignant fibrous histiocytoma (MFH) exhibits an extremely adverse prognosis. Investigations into the principles determining the biological aggressiveness of this cardiac tumor would be facilitated by an appropriate in vitro model. Therefore, we report on the first permanent cell line (MFH-H), derived from a human cardiac MFH. The original tumor had shown coexpression of cytoskeletal filaments typical of mesenchymal (vimentin), epithelial (cytokeratins) and neurogenic (neurofilaments) differentiation. This potential for multidirectional differentiation was observed in the MFH-H cell line as well and indicated marked plasticity of gene activation acquired during the process of neoplastic transformation. Pronounced genetic alterations also became evident from cytogenetic analysis, which revealed a highly variant karyotype with multiple numeric and structural chromosomal aberrations. Secretion of G-CSF, GM-CSF and M-CSF was shown to be another feature of deregulated gene expression in MFH-H cells. Direct autocrine effects of their hematopoietic growth factors, however, were precluded by the lack of the corresponding receptors. In conclusion, the cell line MFH-H will provide an appropriate in vitro model to analyze the biological properties of this cardiac malignancy in more detail, especially with regard to a possible immunomodulating capacity of MFH-derived hematopoietic growth factors.