Acquired Capabilities of Cancer

Acquired Capabilities of Cancer

From: Hanahan D. Weinberg RA. The hallmarks of cancer. Cell. 2000 Jan 7;100(1):57-70

Tumor Development Occurs in Stages

Weinberg RA. How cancer arises. Sci Am. 1996 Sep;275(3):62-70.

Tumor Development Occurs in Stages, cont.

Weinberg RA. How cancer arises. Sci Am. 1996 Sep;275(3):62-70.

Genetic abnormalities in cancer cells1. Oncogenes get activated or become expressed more

than normal

– Oncogene: a gene that, when mutated or dysregulated, participates in the onset and development of cancer

– The protein may be• expressed at a greater level (more protein in the cell)• become more active• lose its potential to be regulated• increase its stability (hang around in the cell longer)

– These changes can cause the cell to be hyper-responsive to growth signals, grow in the absence of proper growth signals, evade apoptosis, etc.

Genetic abnormalities, cont.2. Tumor suppressor genes stop working

– Tumor suppressor gene: a gene that protects a cell from one step in the cancer pathogenesis process

– The gene product may be a protein that maintains the normal cell cycle, inhibits an oncogene, inhibits cell division, etc.

– When a tumor suppressor gene is mutated or dysregulated, the cell can progress to cancer if other aberrations are also present

Gibbs WW. Untangling the roots of cancer. Sci Am. 2003 Jul;289(1):56-65.

Cancer can spread to other sites

Ruoslahti E. How cancer spreads. Sci Am. 1996 Sep;275(3):72-7.

Cancer can spread to other sites, cont.

Ruoslahti E. How cancer spreads. Sci Am. 1996 Sep;275(3):72-7.

New cases of cancer in the U.S.

American Cancer Society. Cancer Facts & Figures 2008. Atlanta: American Cancer Society; 2008.

Cancer deaths among U.S. men

Cancer deaths among U.S. women

(includes cervix)

Role of body weight and IGF-1 in cancer development

Trends Endocrinol Metab. 2006 Oct;17(8):328-36

T. vaginalis

•Parasitic protozoan

•Infection affects 5-20% of U.S. young adults, typically asymptomatic in males

•Causes inflammation and may induce anti-apoptosis genes

•Preliminary data suggest that infection is linked to higher risk of aggressive prostate cancer