International Journal of Cell Cloning, Vol 9, 155-165, Copyright © 1991 by AlphaMed Press

ORIGINAL ARTICLES

The density of clonogenic cells in human solid tumors

F Baker and L Sanger
Baker Sanger, Inc., Houston, Texas 77054.

Considering that tumors are maintained by clonogenic cells, and that the primary target in the therapy of cancer is the clonogenic cell, the density of clonogens in a tumor could become an important parameter in quantitating the response to therapy. Indirect methods for determining the density of clonogenic cells in human tumors based on the response of tumors to radiation suggest there are circa 1 X 10(5) clonogens per gram with a large range. Direct methods, based on the measurement of cloning efficiency of enzymatically disaggregated biopsies of human tumors in soft agar, suggest a clonogen density of approximately 1,500 clonogens per gram. As this value is inconsistent with the prior data, we chose to determine the density of clonogenic cells in human tumors by assaying the enzyme digest of biopsies of human tumors for clonogenic cells using an enriched monolayer clonogenic assay. We determined the average clonogen density to be 1.12 x 10(5) clonogens per gram with a large range. The agreement with the indirect method suggests that the enriched monolayer clonogenic assay supports the proliferation of the cell population responsible for maintaining the tumor.

This article has been cited by other articles:

				J. B. Weidhaas, D. M. Eisenmann, J. M. Holub, and S. V. Nallur A Conserved RAS/Mitogen-Activated Protein Kinase Pathway Regulates DNA Damage-Induced Cell Death Postirradiation in Radelegans Cancer Res., November 1, 2006; 66(21): 10434 - 10438. [Abstract] [Full Text] [PDF]

				J. B. Weidhaas, D. M. Eisenmann, J. M. Holub, and S. V. Nallur A Caenorhabditis elegans tissue model of radiation-induced reproductive cell death PNAS, June 27, 2006; 103(26): 9946 - 9951. [Abstract] [Full Text] [PDF]