• Department of Pathology
  • Pathology Staff
• Department of Laboratory Medicine
  • Laboratory Medicine Staff
• Affiliated Hospitals
  • Moffitt-Long
  • Mount Zion Medical Center
  • San Francisco Veterans Affairs Medical Center
  • San Francisco General
• Faculty
  • Pathology
  • Laboratory Medicine

Research and Clinical Interests

We study the epigenetic and genetic alterations that confer genomic instability and fuel cancer initiation and progression. Recently we identified a variant subpopulation of human mammary epithelial cells (vHMEC) that express properties of premalignant lesions without any exposure of the cells to carcinogens. These variant cells exist in vivo in disease-free women. We have also demonstrated that stromal changes extend beyond a supportive role and play key functional roles in facilitating tumorigenesis. We are studying the ability of carcinoma-associated fibroblasts from human tissues to facilitate the transition to tumorigenicity in an otherwise non-tumorigenic cell population.

Selected Publications

• Olumi, AF., Grossfeld, GD., Hayward, SW., Carroll, PR., Tlsty, TD., and Cunha, GR. “Carcinoma-associated Fibroblasts Direct Tumor Progression of Initiated Human Prostatic Epithelium” Cancer Research, 61: 5002-5011, 1999
• Romanov, S., Kozakiewicz, BK., Holst, CR. Stampfer, MR., Haupt, LM., and Tlsty, TD. “Normal Human Mammary Epithelial Cells Spontaneously Emerge from Senescence and Acquire Genomic Instability.” Nature 409:633-637, 2001
• Crawford YP, Gauthier M, Joubel A, Mantei K, Kozakiewicz BK, Afshari C, Tlsty TD. “Histologically normal human mammary epithelia with silenced p16INK4a overexpress COX-2, promoting a premalignant program” Cancer Cell 5(3):263-73, 2004
• Berman H, Zhang J, Crawford YG, Gauthier ML, Fordyce CA, McDermott KM, Sigaroudinia M, Kozakiewicz, Tlsty TD, “Genetic and Epigenetic Changes in Mammary Epithelial Cells Identify a Subpopulation of Cells Involved in Early Carcinogenesis” Cold Spring Harbor Symposia on Quantitative Biology, Volume 70:317-27, 2005
• Reynolds PA, Sigaroudinia M, Zardo G, Wilson MB, Benton GM, Miller CJ, Hong C, Fridlyand J, Costello JF, Tlsty TD, “Tumor Suppressor p16INK4A Regulates Polycomb-Mediated DNA Hypermethylation in Human Mammary Epithelial Cells” J Biol Chem. Jun 9, 2006

Selected Awards

• Fellow of the American Association for the Advancement of Science 2003
• National Cancer Institute Knudson Award 2003
• National Cancer Institute, Board of Scientific Advisors

• Professor
• Pathology

Specialty Area

Cancer Research

Contact Information

• thea.tlsty@ucsf.edu
• Phone: (415) 502-6115
• Fax: (415) 514-3165

• 513 Parnassus Avenue
• Room HSW-513, Box 0511
• San Francisco, CA 94143-0511