Cell kinetics in tumour cords studied by a model with variable cell cycle length.
ABSTRACT A mathematical model is developed that describes the proliferative behaviour at the stationary state of the cell population within a tumour cord, i.e. in a cylindrical arrangement of tumour cells growing around a blood vessel and surrounded by necrosis. The model, that represents the tumour cord as a continuum, accounts for the migration of cells from the inner to the outer zone of the cord and describes the cell cycle by a sequence of maturity compartments plus a possible quiescent compartment. Cell-to-cell variability of cycle phase transit times and changes in the cell kinetic parameters within the cord, related to changes of the microenvironment, can be represented in the model. The theoretical predictions are compared against literature data of the time course of the labelling index and of the fraction of labelled mitoses in an experimental tumour after pulse labelling with 3H-thymidine. It is shown that the presence of cell migration within the cord can lead to a marked underestimation of the actual changes along cord radius of the kinetics of cell cycle progression.
- SourceAvailable from: oa.lib.ksu.edu.tw01/1970; Academic Press., ISBN: 978-0-12-528550-6
Article: Cell Kinetics in a Tumour Cord[show abstract] [hide abstract]
ABSTRACT: In some tumours, the viable cells grow around blood vessels forming cylindrical structures called tumour cords, which are surrounded by regions of necrosis. In the present paper, we propose a mathematical model for the cell kinetics in a tumour cord at the stationary state. Both proliferating cells and quiescent cells are considered, and the proliferating cell population is structured by age. Cell migration towards cord periphery is accounted for from a continuum viewpoint. The age distribution of proliferating cells, the fraction of cells in S phase, the growth fraction and the velocity along the cord radius are computed. The predictions of the model are compared with literature data obtained from two experimental rat hepatomas. The model was used to compute the profile of the oxygen tension within the cord. Possible modifications and extensions are also presented.Journal of Theoretical Biology 07/2000; · 2.35 Impact Factor
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ABSTRACT: The proliferation pattern of a transplantable mouse mammary carcinoma has been studied in relation to its macroscopic and microscopic structure. No significant differences were seen in the labelling or mitotic indices or in the percentage labelled mitoses curves for the peripheral 2.0 mm rim or for the central tumour core. When these parameters were scored for cells classified according to their position in relation to capillaries or to necrotic regions, marked differences were observed in all the parameters. Higher labelling and mitotic indices and higher grain counts were seen adjacent to the capillaries. These appear to result from a shorter cell cycle duration and a higher growth fraction. The variation in cell cycle is mainly due to a change in the duration of G1.Cell and tissue kinetics 02/1979; 12(1):31-42.