Project: Research project

Project Details


Sodium butyrate induces a more differentiated and less tumorigenic
phenotype of HT-29 human colon carcinoma cells in vitro. We have cloned a
cDNA library of sequences expressed in HT-29 cells and have developed a
computerized scanning and image processing system to quantitate the
relative level of expression of each of 4000 members of this library in
tissue biopsies or cells in culture. We will also produce two new more
extensive cDNA libraries from cell lines which stably differentiated during
treatment of HT-29 cells with butyrate. These cell lines, 16E and 19A,
each exhibit properties of different lineages of colon cell differentiation
(mucin secretion and vectorial transport), and these properties continue to
be expressed in the absence of inducer. These libraries will be produced
in the bacterial expression vector Lambdagt11. Utilizing all three
libraries and the computer-linked methodology we have developed, we will
identify sequences which are altered in expression during treatment with
sodium butyrate, the time course of such alterations and association with
acquisition of various traits characteristic of a more differentiated
phenotype, the time necessary for commitment to such changes during
butyrate treatment, and the stability and reversal of such changes after
withdrawal of butyrate. In a continuation and extension of work we have
done on expression of proto-onc sequences in the stably differentiated cell
lines, we will investigate the expression of proto-onc sequences of the myc
and ras gene family in these experiments.

We will also determine the time course of change in gene expression in two
other human colon carcinoma cell lines, SW480 and SW1116, during butyrate
treatment in order to determine if similar changes are consistently
observed in these other lines. Finally, a monoclonal antibody which
recognizes the peptide of colon mucin will be used to isolate this mRNA
from one of the Lambdagt11 libraries, and subsequently study the effects of
sodium butyrate on expression of this gene in the experiments outlined.
Effective start/end date12/31/8912/31/90


  • National Cancer Institute
  • National Cancer Institute
  • National Cancer Institute


Explore the research topics touched on by this project. These labels are generated based on the underlying awards/grants. Together they form a unique fingerprint.