Our findings suggest that this mutation in a single allele of the PAX5 gene is not sufficient to cause disease, and it is possible that other alleles are also involved in the onset of B-ALL.
Given the pivotal importance of Pax-5-mediated processes in B-cell development, an aberrant regulation of Pax5 expression has consistently been associated with B-cell cancers, namely, lymphoma and lymphocytic leukemias.
The key factors required for B-cell and dendritic cell development, PAX5 and ID2, were differentially expressed, with a strong PAX5 signal in the acute B-lymphoblastic leukemia and only a weak expression in the Langerhans' cell sarcoma, whereas ID2 showed an opposite pattern.