According to results presented at the 2004 International Bone Marrow Transplant Registry/American Association for Blood and Marrow Transplant (IBMT/ASBMT) tandem meetings, specific genes and gene profiling will undoubtedly become components involved in treatment decisions for patients with acute lymphoblastic leukemia (ALL). Presenters at the meeting stressed that it is important for specimens of patients’ cancer cells to be stored in order to perform such genetic studies.
Acute lymphoblastic leukemia (ALL) is a cancer of the bone marrow and lymph system. The bone marrow produces early blood-forming cells, called stem cells, which grow and mature into the three blood cell types: white blood cells, which fight infection; red blood cells, which carry oxygen to tissue; and platelets, which help blood to clot. ALL is characterized by uncontrolled production of immature lymphocytes (white blood cells), of which there are two types: B and T cells. These immature lymphocytes never mature enough to perform their specific function of fighting infection. In addition, these rapidly dividing cells crowd out and suppress the formation of other important blood cells, such as red blood cells, platelets and other white blood cells. ALL is an aggressive cancer that must be treated aggressively for optimal chances of a cure.
Gene therapy appears to be quickly emerging into the clinical setting in oncology. It is becoming increasingly clear that differences in genetic make-up or genetic sequences between patients with the same disease plays a role in the prognosis of the patient, and ultimately may play a large role in determine the optimal treatment strategies for each individual patient. Researchers recently analyzed gene expression in patients with ALL and possible associations with prognosis. The researchers analyzed a set of 3 genes, singly referred to as G0, G1, and G2. The set of these 3 genes is referred to as “outcome predictor in acute leukemia”, or OPAL1. Researchers found that leukemias expressing high levels of OPAL1 were associated with a survival rate of 87%, compared to a survival rate of 32% in patients with leukemias that expressed low levels of OPAL1.
1 In addition, researchers also presented results indicating several gene profiles that may improve the present method of sub-grouping ALL, promising greater understanding and treatment specificity for patients in the future. The researchers announced that the storage of leukemia cells from patients has become an important action to take in order to provide genetic information for future use, and help tailor individual treatment regimens.
The researchers from these meetings concluded that high expression of OPAL1 strongly correlates with improved survival rates in patients with ALL, and the storage of leukemia cells has become a very important task. Patients with ALL should discuss the risks and benefits of cellular storage as well as genetic profiling with their physician.
- Mosquera-Caro M, Helman P, Veroff R, et al. Identification, Validation, and Cloning of a Novel Gene (OPAL 1) and Associated Genes Highly Predictive of Outcome in Pediatric Acute Lymphoblastic Leukemia Using Gene Expression Profiling. Blood 2004;102:4a, Abstract #1.
- Fine B, Stanulla M, Schrappe M, et al. Gene Expression Patterns Associated with Recurrent Chromosomal Translocations in Acute Lymphoblastic Leukemia. Blood 2004;103;1043-1049.