Abstract
To test the identity of human tumour clonogenic cells and stem cells, a procedure was developed to allow quantitation of self-renewal capacity of human ovarian carcinoma clonogenic cells. Primary colonies grown from malignant effusions of 10 patients were disaggregated and replated, secondary colonies were observed to be similar to primary colonies in size, morphology and culture requirements. Density-gradient separation of tumour-cell populations demonstrated that not all primary clonogenic cells are capable of self-renewal during clonal expansion. Patient-to-patient variation in self-renewal capacity was shown to be significantly correlated with the concentration of the tumour-cell population in the effusion fluid, and preliminary evidence of a progressive increase in self-renewal was found in one patient. It was concluded that some, but not all, ovarian-tumour clonogenic cells have the stem-cell property of self-renewal, and that quantitation of such a property may identify an important prognostic variable.