Stem Cell Report – January 2001

Clinical successes in cancer treatment again show versatility, pluripotent abilities of adult stem cells.

Clinical use for adult stem cells have shown positive results in treating metastatic retinoblastoma. This spreading tumor of the eye has a poor prognosis with conventional treatments. Using chemotherapy with autologous (same patient) stem cell transplant, all patients in one study were in remission 46-80 months after diagnosis.

Adult stem cells have also been successful with Merkel cell carcinoma, a rare aggressive skin cancer for which there is no standard protocol for treatment. This study used high-dose chemotherapy and autologous peripheral blood stem cell transplantation to achieve complete remission that lasted for 6 months.

Further successes have also been achieved against breast cancer. In a recent study, clinicians found that the “data suggest that high-dose chemotherapy with hematopoietic stem cell rescue is safe and can be beneficial to patients with high-risk primary breast cancer and for those with metastatic breast cancer achieving complete response/no evidence of disease.”

In a review of adult stem cell transplantation, physicians noted that ” [Adult] Stem cell transplantation has been successfully used to treat a wide variety of hematologic malignancies” (cancers of the blood).¹

Adult stem cells again proved capable of numbers to meet clinical demand

Confirming other research on the ability of adult stem cells to grow and expand and thus create adequate supplies for effective clinical use, Cashman and Eaves, in the journal Blood, found that “Previously reported human stem cell frequencies and their in vivo self-renewal activity have been markedly underestimated.” Gilmore and co-workers used specific growth factors to expand the numbers of stem cells from cord blood and adult patient peripheral blood, finding that these adult stem cells could be “maintained for prolonged periods (up to 16 weeks), and sufficient numbers were generated for adult transplantation.”²

Treating heart disease with adult stem cells

Canadian scientists have incorporated adult bone marrow (“stromal”) cells into heart muscle tissue in rats, using the rats’ own cells (an “autologous” transplant.) The scientists said: “Because marrow stromal cells can be obtained repeatedly by bone marrow aspiration and expanded vastly in vitro before being implanted or used as autologous implants, and because their use does not call for immunosuppression, the clinical use of marrow stromal cells for cellular cardiomyoplasty appears to be most advantageous.”

Another group compared the ability of fetal heart cells (“cardiomyocytes”) versus skeletal muscle cells (“myoblasts”) for repair of heart damage after heat attack. The researchers found that the adult stem cells were just as good at repairing heart damage as fetal cells. They also had the advantage of being obtainable from the patients themselves, preventing transplant rejection complications: “These results support the hypothesis that skeletal myoblasts are as effective as fetal cardiomyocytes for improving postinfarction left ventricular function. The clinical relevance of these findings is based on the possibility for skeletal myoblasts to be harvested from the patient himself.”

A 72-year-old patient in France, who had severe heart failure, has already been treated with just such an adult cell transplant. Doctors grew a bit of his thigh muscle into millions of cells in culture, then transplanted the cells into and around his damaged heart muscle. Dr. Philippe Menasche of Bichat Hospital in Paris said the patient had improved dramatically; “We repopulated the dead scar with living cells.”³