We report the cytogenetic analysis of 124 adult male germ cell tumors ascertained consecutively at the Memorial Sloan-Kettering Cancer Center between 1988 and 1990. Biopsies from testicular and extragonadal primary and metastatic lesions studied included all histological subtypes of germ cell tumors and cases of malignant transformation. Nonrandom numerical and structural chromosomal abnormalit...

We report a new method for in situ localization of DNA sequences that allows excellent preservation of nuclear and chromosomal ultrastructure and direct, in vivo observations. 256 direct repeats of the lac operator were added to vector constructs used for transfection and served as a tag for labeling by lac repressor. This system was first characterized by visualization of chromosome homogeneou...

Previous studies from our laboratory have demonstrated specific cytogenetic alterations accompanying development of colchicine resistance in the J774.2 murine cell line and in two sublines (J7.Cl-30 and J7.Cl-100). Although gene amplification is not observed in the parental J774.2 cell line, a approximately 35-fold amplification of the gene for p-glycoprotein (mdr) was noted in the J7.Cl-30 sub...

Chromosomal abnormalities associated with five in vitro-transformed male mouse salivary gland epithelial cell lines were compared with those in three cell lines derived from in vivo-induced tumors. All cell lines were hypotetraploid. Structural chromosome abnormalities were found in all cell lines, but no consistent aberration was detected. Nevertheless, losses of chromosomes 1, 4, 7, 9, and 14...

An analysis of the chromosomal karyotype of the human promyelocytic HL-60 leukemia cell line and of a number of its sublines that exhibit varying degrees of resistance to induction of differentiation by phorbol-12-myristate-13-acetate was conducted. The HL-60 cell line and the derived sublines contained two consistent marker chromosomes [9p- and t(10;13)], which suggested that they have a commo...

Amplification of DNA in certain chromosomal regions, with consequent over-expression of specific genes within these amplicons, plays a crucial role in the development and progression of human cancer. Since our previous comparative genomic hybridization (CGH) study revealed frequent amplifications at 18p in esophageal squamous cell carcinomas (ESC) cell lines, we focused on the identification of...

Multiple myeloma is a disease with a high initial chemotherapeutic response but virtually no cures due to emergence of drug resistance. A doxorubicin-resistant human myeloma cell line (8226/Dox) has been selected from the myeloma cell line RPMI8226 by continuously exposing cells to gradually increasing doses of doxorubicin. The resistant phenotype has been retained for over 2 months despite gro...

The use of lanthanum salts has made possible the staining of extracellular regions which are not electron opaque when conventional methods of fixation and staining for electron microscopy are employed (3, 6, 10). The present work describes the staining of the intestinal epithelium by this means. Intercellular regions in the intestinal wall generally stain intensely, as has been described previo...

The nucleus tractus solitarii (NTS), which receives visceral afferent information from the cardiovascular, respiratory, gastrointestinal and taste systems, contains multiple neurotransmitters and neuropeptides throughout its rostral to caudal extent. The neurotransmitters and neuropeptides immunoreactivity is located predominately in varicose fibers and small puncta throughout the neuropil. In ...

Homogeneously staining regions (HSRs) were found in hypodiploid cells (40%) of a subline of the human melanoma cell line, MeWo, (MeWo-C) but were absent from the hypotetraploid cells (60%). Another subline (MeWo-B) was also shown to contain two populations of cells, 70% hypodiploid and 30% hypotetra ploid. None of the MeWo-B cells contained HSRs, but all four cell types from both sublines share...