December 12, 2011
By KUMC News
Vitamin D can cause cancerous bone cells to turn into normal bone cells, according to research by scientists at the University of Kansas Medical Center (KUMC). The discovery may lead to new treatments for pediatric bone cancer, the scientists say.
Recent studies have shown that vitamin D may be helpful in treating cancer of the breast, prostate and colon by inhibiting the growth of malignant cells. KUMC scientis built on that foundation, using tests to show that vitamin D produces a similar response in osteosarcoma -- a type of malignant bone tumor that mainly affects children and adolescents.
Vitamin D, which is best known for helping the body absorb calcium, has the ability to go into the nucleus of a cell and affect how it functions. In laboratory tests conducted at KUMC, vitamin D prevented osteosarcoma cells from replicating as quickly and promoted the growth of normal bone cells. The findings appear in the Journal of Orthopaedic Research.
Osteosarcoma tends to occur in larger bones near the knee or the shoulder. The cancer usually develops when bones are growing the fastest, which is why it is associated with puberty. Between 500 and 800 cases are diagnosed in the United States each year.
Typically, osteosarcoma patients receive 10 weeks of chemotherapy before the tumor is removed surgically. The survival rate is 60 to 70 percent. "We need to improve what we're currently doing," says Kim Templeton, MD, an orthopedic surgeon at The University of Kansas Hospital, who initiated this project and is one of the co-authors of the study.
The results suggest that vitamin D could become another tool in the treatment of osteosarcoma. Patients with deficient levels of vitamin D would potentially receive supplements during chemotherapy in an effort try to increase the number of osteosarcoma cells that turn into normal bone.
Existing treatments for osteosarcoma are in a state of "gridlock," according to Ossama Tawfik, MD, PhD, a professor in the Department of Pathology and Laboratory Medicine at KUMC and a co-author of the study. "It's a deadly disease that's waiting for an answer," Tawfik says.
Rama Garimella, PhD, a research assistant professor in the Department of Dietetics and Nutrition at KUMC, is the senior and corresponding author of the study. Lindsey Thompson, a research assistant in the Department of Dietetics and Nutrition, is the study's first author. Shanshan Wang, Jakica Tancabelic, MD; David Pinson, DVM, PhD; H. Clarke Anderson, MD; and John Keighley, PhD, are also co-authors.
The discovery is promising given that vitamin D, in addition to being inexpensive, poses no long-term side effects when taken in normal doses. "The chemotherapy that is used now is great at killing the cancer for most patients, but there are also significant side effects on the heart or the kidneys or bone, depending on which drug you're looking at," Templeton says. "The beauty of vitamin D is that at relatively normal doses, it's not going to have a long-term side effect like that. When you're dealing with growing kids, that's something you really need to be concerned about."
Templeton is recognized as a leader in orthopedic oncology. In 2008, she was the first doctor in the United States to use a titanium alloy rod to save the limb of a cancer patient. In 2009, she led a surgical team that performed a procedure that was designed to give a 19-year-old patient greater use of a prosthetic arm. The procedure, called targeted muscle reinnervation, had never been performed on a cancer patient. She presented the technique and the results of this procedure at the first international conference on targeted muscle reinnervation in Chicago in October.