Honami Naora, Ph.D., an assistant professor in M. D. Anderson's Department of Molecular Therapeutics and her colleagues discovered that a set of shape-altering genes become activated in ovarian cancer. These HOX genes, better known for their role in normal embryonic development, direct the cancer cells to take a variety of different forms, depending on which of the genes is turned on. The researchers reported their finding in the April 10, 2005 on-line issue of the journal Nature Medicine.
"Our finding explains how each of the three major forms of ovarian cancer acquire their unique appearance," says Naora. "These genes cause a metamorphosis of the ovarian epithelial cells, directing them to change their shape."
These strange shapes make each form of ovarian cancer different from one another, and also different to the surface epithelium or outer covering of the ovary from which these cancers are thought to arise, explained Naora. Serous ovarian cancer exhibits features resembling those of the fallopian tubes; the endometrioid form has features resembling the lining of the uterus; mucinous ovarian cancer even looks like intestinal cells.
These mysterious shapes have caused some researchers to speculate that ovarian cancers might originate from some other tissues, and not the ovarian surface epithelium at all.
Contact: Nancy Jensen
University of Texas M. D. Anderson Cancer Center