Action of cyclic adenosine 3':5'-phosphate in Chinese hamster ovary cells

Conference · Wed Jan 01 04:00:00 EST 1975

OSTI ID:7368372

Hsie, A W; O'Neill, J P; Schroeder, C H; Kawashima, K; Borman, L S; Li, A P

The epithelial-shaped CHO cells growing randomly in vitro in a compact, multilayered colony convert into a contact-inhibited monolayer of elongated, fibroblast-like cells when treated with Bt/sub 2/cAMP (or purified cholera toxin). The morphological conversion is also accompanied by the disappearance of cell surface knobs, decrease in cellular agglutinability, an increase in the number of microtubules and their arrangement in parallel arrays along the long axis of the cell, and induction of collagen synthesis. Continuous exposure of CHO cells to Bt/sub 2/cAMP had at most only minor effects on progression through the cell cycle. Only cells in the G/sub 1/ phase of the cycle initiate elongation when incubated with Bt/sub 2/cAMP. Hormones such as testosterone and prostaglandins exert the morphological effects synergistically with Bt/sub 2/cAMP. Although the mechanisms of morphological transformation and its associated reversal of certain properties associated with malignancy of CHO cells in vitroare as yet obscure, it is clear, however, that a fundamental change in membrane properties is involved. Such a change may result in altered cellular permeability to essential nutrients, which in turn may regulate growth and differentiation. Experiments with mammalian cells derived from mouse embryo, mouse neuroblastoma, and rat hepatoma have shown that cAMP and/or its dibutyryl derivatives also alter the morphology and growth rate of those cells. Thus it is possible that cAMP alone or in combination with certain hormones has a central role in regulating the morphology and growth of all mammalian cells. Finally, variants with altered properties of morphological transformation have been isolated, and it is expected that genetic analyses and biochemical characterizations of these variants and their parental cells will aid in the elucidation of the molecular mechanisms involved in the morphological and its associated characteristics. (auth)

• Research Organization: Oak Ridge National Lab., Tenn. (USA)
• OSTI ID: 7368372
• Report Number(s): CONF-751211-1
• Country of Publication: United States
• Language: English

Related Subjects

550300* -- Cytology
59 BASIC BIOLOGICAL SCIENCES
AMP
ANIMAL CELLS
ANIMALS
BIOLOGICAL EFFECTS
BODY
CELL CONSTITUENTS
CELL CYCLE
CELL MEMBRANES
FEMALE GENITALS
GONADS
HAMSTERS
HORMONES
MAMMALS
MEMBRANES
MORPHOLOGICAL CHANGES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANS
OVARIES
RODENTS
SYNERGISM
TUMOR CELLS
VERTEBRATES