Effect of rapamycin on mouse chronic lymphocytic leukemia and the development of nonhematopoietic malignancies in Emu-TCL1 transgenic mice.

Chronic lymphocytic leukemia (CLL) is the most common leukemia in the world. The TCL1 gene, responsible for prolymphocytic T cell leukemia, is also overexpressed in human B cell malignancies and overexpression of the Tcl1 protein occurs frequently in CLL. Aging transgenic mice that overexpress TCL1 under control of the mu immunoglobulin gene enhancer, develop a CD5+ B cell lymphoproliferative disorder mimicking human CLL and implicating TCL1 in the pathogenesis of CLL.

Establishment and characterization of four cell lines derived from human head and neck squamous cell carcinomas for an autologous tumor-fibroblast in vitro model.

To study interactions between tumor cells and stromal elements, we established carcinoma cell lines as well as tumor-derived and skin fibroblast cultures from four patients with squamous cell carcinoma of the head and neck. For the characterization of the tumor cell lines we a) determined population doubling times, b) assessed morphological features by light and electron microscopy, c) investigated the expression of typical markers by immunohistochemistry, including various intermediate filaments and surface antigens, d) compared these findings with expression patterns in the respective original tumor specimens, e) evaluated p53 mutations in tumor specimens and cell lines, f) performed chromosome analysis, g) investigated the tumorigenicity in athymic mice, and h) tested the formation of both tumor and mixed tumor-fibroblast multicellular spheroids. Tumor cell cultures were considered established cell lines when maintained and passaged over a period of two years after primary explantation.

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.

Characterization of two newly established cell lines derived from squamous cell carcinomas of the oesophagus.

This study describes characteristics of two newly established cell lines (OSC-1 and OSC-2), derived from two oesophageal squamous cell carcinomas. Morphologically, OSC-1 cells and OSC-2 cells grew in epithelial cobblestone patterns with cells piling up to 4 cells. Ultrastructurally, both cell lines showed formation of desmosomes; however, tonofilaments were only formed by OSC-2 cells.

Chromophilic renal cell carcinoma: cytomorphological and cytogenetic characterisation of four permanent cell lines.

Chromophilic renal cell carcinoma is a distinct type of human renal cancer, only recently recognised and defined by its characteristic histomorphological aspect and cytogenetic aberrations. We are the first to report on the establishment and cytogenetic characterisation of a panel of four permanent cell lines, i.e.