1st molecular evidence of link betweenembryonic stem cells and cancer--breast cancer

and seminoma (testicular cancer):
ABSTRACT: Involvement of Stem Cell Genes in Breast and Germ Cell Tumors [Cancer Biology & Therapy; Subscribe]
UCSF scientists have discovered that the activity of several embryonic stem cell genes is elevated in testicular and breast cancers, providing some of the first molecular evidence of a link between embryonic stem cells and cancer.

The finding, reported in the November, 2005 issue of the journal Cancer, suggests that the genes may play a role in the development of tumors or serve as valuable markers of tumor progression, the researchers say. As such, the genes ultimately could lead to new targets for therapy or markers for diagnosis.

A next step, according to the researchers, will be to "dig deeper" to determine the functions of the genes in the cells that make up the tumors. Another step will be to explore whether the genes are expressed in other cancers, such as prostate cancer.

The genes are known as OCT 4, NANOG, STELLAR and GDF3.

The researchers focused on seminomas - tumors that account for 50 percent of the cases of testicular cancer, the most frequent cancer in Caucasian males ages 15-40 — and breast cancers, as represented by a sample of breast cancer cells grown in the culture dish and tissue from a Stage 3 breast tumor.

Previously, the team had discovered that expression of the genes was elevated in two samples of seminomas (Stem Cells, March 2004). In the current study, they expanded their investigation, determining that the expression of the genes was elevated, at varying levels, in nine seminomas.