PLACE:  319 Snedecor

SPEAKER:
Simon Tavaré
Departments of Biological Sciences and Mathematics and
Preventive Medicine, University of Southern California

TITLE:
Reconstructing Tumor Histories

ABSTRACT:

Progression to  cancer is difficult to observe directly because mutations may accumulate before the appearance of detectable precursors, and adenomas are usually removed In this talk I describe a statistical approach we have used to reconstruct tumor histories in male colon cancer patients by using variation in somatic microsatellite mutations. Tumor progression is modeled as a branching process on which the microsatellite mutations are superimposed. The history of the process is inferred from a sample of tumor cells in which  the microsatellite repeat lengths are measured. A computationally intensive inference method that simulates the genealogy of the sample of cells is used to estimate the age of the tumor, and a bootstrap technique is used to assess the adequacy of the approach.  [No knowledge of molecular biology will be assumed.]
 

References:
Tavaré, S. (1999).  Random trees in  molecular genetics.  Bull. ISI., 52,
269-272.
Tsao J.-L., Tavaré, S., Salovaara R., Jass, J.R., Altonen, L.A. and Shibata,
D. (1999) Colorectal adenoma and cancer divergence: evidence of multi-lineage
progression. Am. J. Pathol. 154, 1815-1824.
Tsao J.-L., Yatabe ,Y., Salovaara, R., Järvinen, H. J., Mecklin, J.-P.,
Altonen,
L. A., Tavaré, S. and Shibata, D. (2000) Genetic reconstruction of individual
colorectal tumor histories. Proc. Natl. Acad. Sci. USA, 97, 1236-1241.
These papers can be downloaded from
http://www-hto.usc.edu/papers/abstracts/villars.html
 

COFFEE: 10:30 a.m., 104 Snedecor