Insulin-Like Growth Factor-II mRNA-Binding Protein Expression in Leukemias and Lymphomas
MP LeGolvan, S Hao, BA Woda. UMassMemorial Healthcare, Worcester, MA
Background: Leukemias and lymphomas represent a heterogeneous group of neoplasms. Diagnostic markers are already well established in most of the individual neoplasms; however, prognostic markers, while growing in number, are still being elucidated. The family of Insulin-like growth factor II mRNA-binding protiens (IMP), which includes IMP1, IMP2, and IMP3, are oncofetal proteins expressed in embryogenesis. While absent or present in very low levels in adult tissue, they have now been found to be present in a number of cancers. IMP3 has been the most widely studied and recently has been shown to hold prognostic significance. Yet, IMP3 has had limited study in leukemias and lymphomas, and neither IMP1 nor IMP2, to our knowledge, has been addressed in these neoplasms. We focused on a wide range of hematopoeitic neoplasms to evaluate the staining patterns and possible utility of these newly emerging markers for diagnostic or, more likely, prognostic use.
Design: 86 cases of representative leukemias and lymphomas from 2004-2008 were collected from the archives of UMassMemorial Medical Center and stained with IMP1(Aviva systems BIO), IMP2 (Affinity Bioreagents), and IMP3 (DAKO) from a previously published protocol using a DAKO autostainer. 9 acute lymphoblastic leukemias (ALL), 9 acute myeloid leukemias (AML), 8 Hodgkin lymphomas, classic (CHL), 9 chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL), 7 diffuse large B-cell lymphomas (DLBCL), 10 follicular lymphomas (FL), 8 mantle cell lymphomas (MCL), 7 multiple myelomas (MM), 10 marginal zone lymphomas (MZL), and 9 T-cell lymphomas (PTCL) were utilized.
Percentage of Positive Staining of IMP1,2,3
|IMP1 (%)||IMP2 (%)||IMP3 (%)|
Conclusions: 1. IMPs are expressed in 100% of DLBCL. 2.IMP1 and IMP3 are useful surrogate markers for CHL when CD30 expression is inconclusive. 3. IMPs are variably expressed in ALL, PTCL and MCL. Further studies are needed to investigate the possible prognostic significance in these tumors. 4. IMPs are not expressed in MM, and rarely expressed in low grade B-cell lymphomas with the exception of FL. 5. IMP3 is expressed in all FL and DLBCL. Further study is needed to investigate the possible role in diagnosis of lymphomas of follicular center cell origin. 6. IMP2 is expressed in all AML but IMP1 and IMP3 were not detected.
Tuesday, March 10, 2009 9:30 AM
Poster Session III # 131, Tuesday Morning