Gene Therapy May Provide New Answers to Fibroid Problems

Research from the U-M Women's Health Program suggests that gene therapy may someday control a condition responsible for nearly half the 550,000 hysterectomies performed in the United States each year.

Leiomyoma tumors-commonly known as fibroids — are benign growths that develop in the uterus and often cause pelvic pain, abnormal uterine bleeding, excessive urinary pressure, decreased fertility, and increased chance of miscarriage. Treatment typically involves a hysterectomy that excises the tumors along with the patient's uterus.

The U-M research, however, offers hope of a non-surgical alternative that would leave a patient's uterus, and fertility, intact. U-M researchers, administering DNA tailored to inhibit tumor growth, have effectively killed human leiomyoma cells in laboratory tests and suppressed leiomyoma tumors in lab rats.

The significance of this development is enormous, because fibroids are the most common tumor in humans and hysterectomy is the most common surgical procedure performed in this country. "Leiomoyomas are an incredibly common problem," said Gregory M. Christman, M.D., an assistant professor and research scientist in the Department of Obstetrics and Gynecology and principal investigator in the leiomyoma study. "Our treatment had a pronounced effect in removing the smooth muscle tumor cells, suggesting it may ultimately be feasible to treat uterine leiomyomas with gene therapy."

The method of gene therapy Christman uses has been shown to inhibit the proliferation of malignant cancer cells, but malignancies often grow too fast and DNA delivery systems currently are too imperfect to make this particular method of gene therapy more than a subordinate cancer treatment, he says. On the other hand, uterine leiomyoma cells are benign and slow-growing and their symptoms can be relieved by reducing the volume of tumors. Unlike malignant cells, eliminating every cell is not necessary. Therefore gene therapy that inhibits leiomyomas or induces regression may be sufficient treatment.

The U-M researchers’ next step is to investigate the effectiveness of various systems for delivering the genes into uterine smooth muscle cells in vivo. Christman estimates it will be another two to three years before they are ready to consider and enroll patients in human trials.