PubMed Health⌕ Search

PubMed · 2247489

Growth control in leukemia.

Abstract

Quantitative assays for individual hematopoietic progenitors have provided a powerful approach to the assessment of changes in the absolute and relative numbers of primitive cells in the affected tissues of individuals with CML. These techniques have also been usefully coupled to other ways of assessing these cells to confirm their malignant nature by cytogenetic analysis and to establish and characterize abnormalities in the regulation of their numbers and turnover. A culture system that allows primitive normal and leukemic hematopoiesis to be maintained for many weeks has been developed. This system has been found to reproduce the cardinal features of primitive hematopoietic cell regulation in vivo and its use has allowed important progress to be made in characterizing the molecular basis of stromal cell regulation of primitive hematopoietic cells. Nevertheless, a large gap still remains between our knowledge of the genes that are altered in CML (or other malignancies) and the biological changes underlying the deregulation of growth that is characteristic of malignancy in general. Further exploitation of in vitro systems that allow this deregulation to be analyzed and manipulated appears to offer promise towards bridging this gap in the future.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A C Eaves, C J Eaves. 1990. Growth control in leukemia.. https://pubmed.ncbi.nlm.nih.gov/2247489/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Neuropeptide Y (NPY) in neuroblastoma: effect on growth and vascularization.

Neuroblastomas are pediatric tumors of sympathetic origin, expressing neuronal markers, such as NPY and its receptors. Due to this, neuroblastomas are often associated with elevated plasma levels of NPY, which correlates with poor clinical outcome of the disease. This clinical data corroborates the recent discovery of growth-promoting actions of NPY in neuroblastomas. The peptide has been shown to stimulate proliferation of neuroblastoma cells in an autocrine manner and induce tumor vascularization. Since both processes are mediated by the same Y2 and Y5 receptors, targeting this pathway may be a potential bidirectional therapy for these children's tumors.

Cell Division↗

Characteristics, causes and evolutionary consequences of male-biased mutation.

Mutation has traditionally been considered a random process, but this paradigm is challenged by recent evidence of divergence rate heterogeneity in different genomic regions. One facet of mutation rate variation is the propensity for genetic change to correlate with the number of germ cell divisions, reflecting the replication-dependent origin of many mutations. Haldane was the first to connect this association of replication and mutation to the difference in the number of cell divisions in oogenesis (low) and spermatogenesis (usually high), and the resulting sex difference in the rate of mutation. The concept of male-biased mutation has been thoroughly analysed in recent years using an evolutionary approach, in which sequence divergence of autosomes and/or sex chromosomes are compared to allow inference about the relative contribution of mothers and fathers in the accumulation of mutations. For instance, assuming that a neutral sequence is analysed, that rate heterogeneity owing to other factors is cancelled out by the investigation of many loci and that the effect of ancestral polymorphism is properly taken into account, the male-to-female mutation rate ratio, alpham, can be solved from the observed difference in rate of X and Y chromosome divergence. The male mutation bias is positively correlated with the relative excess of cell divisions in the male compared to the female germ line, as evidenced by a generation time effect: in mammals, alpham is estimated at approximately 4-6 in primates, approximately 3 in carnivores and approximately 2 in small rodents. Another life-history correlate is sexual selection: when there is intense sperm competition among males, increased sperm production will be associated with a larger number of mitotic cell divisions in spermatogenesis and hence an increase in alpham. Male-biased mutation has implications for important aspects of evolutionary biology such as mate choice in relation to mutation load, sexual selection and the maintenance of genetic diversity despite strong directional selection, the tendency for a disproportionate large role of the X (Z) chromosome in post-zygotic isolation, and the evolution of sex.

Cell Division↗

Candida gelsemii sp. nov., a yeast of the Metschnikowiaceae clade isolated from nectar of the poisonous Carolina jessamine.

A new yeast species, Candida gelsemii, is described to accommodate three isolates recovered in Georgia, USA, from the toxic nectar of the Carolina jessamine (Gelsemium sempervirens). The species resembles other members of the Metschnikowiaceae clade that have been recovered from nectar, but differs in a number of morphological and physiological characteristics. Analysis of rDNA sequences places the new species well into the clade, but in a basal position with respect to a group of Metschnikowia and Candida species known to occur in association with nectars and bees, as well as marine invertebrates. The type is strain UWOPS 06-24.1(T) (CBS 10509(T), NRRL Y-48212(T).

Cell Division↗