Fluorescence In Situ Hybridization (FISH) for Detection of c-MYC Amplifications in AML Patients: A Potential Marker for Risk Stratification

Abstract

Abstract Background c-MYC is a transcription factor (located on 8q24) which regulates genes involved in proliferation, cell growth, differentiation, and apoptosis. The c-MYC amplification is related to a rapid proliferation of the affected cell clone in patients with myeloid neoplasms. Gene amplification (amp) is one of the basic mechanisms connected with over-expression of oncogenes. c-MYC is routinely analyzed in mature lymphoid neoplasms especially in Burkitt’s Lymphoma while not assessed for acute myeloid leukemia (AML).Despite the fact the c- MYC oncogene is commonly over-expressed in AML it has remained an elusive target. Routine assessment for c- MYC in AML may pave the way for targeting the c-MYC in treatment of AML patients. Several experiments are ongoing investigating both direct and indirect c-MYC targeting therapies and further establishing cMYC as an oncogene of central importance to AML pathogenesis and treatment. Aim of the Work In this study we aimed to define the prognostic value of c-MYC amplification in adult AML patients, and to relate it to other prognostic factors in AML. Patients and Methods The study was a randomized control study, conducted at the Clinical Pathology Department, Ain-Shams University Hospitals during the period from January 2019 till June 2020. It was carried on 50 adult AML patients (30 newly diagnosed and 20 on Therapy) and 10 healthy age-matched volunteers as control. All subjects underwent full history taking, thorough clinical examination, laboratory investigations including; CBC, Examination of Leishman’s stained peripheral blood films, Bone marrow aspiration and examination of Leishman’s stained bone marrow smears, Cytochemical studies using Myeloperoxidase stain, Immunophenotyping of bone marrow or peripheral blood samples and Fluorescence in situ hybridization analysis (FISH). Results we had 9 patients with c-MYC amplification (6 in the newly diagnosed group and 3 in the on therapy group). So the percentage of c-MYC amplification in our patients was 9/50 (18%). To further elucidate the effect of c-MYC amplification on our patients’ clinical, laboratory and prognostic factors, an analytical comparison was done between negative and positive patients for cMYC amplification as regard-studied parameters in each group of patients. Both group of patients showed a statistical significant association between c-MYC amplification and outcome where the majority of patients with positive c-MYC amplification achieved incomplete remission. In addition, c-MYC amplification showed a statically significant association with Trisomy 8 in both patients’ groups and with 17p deletion and hepatosplenomegaly in on therapy group. Univariate logistic regression analysis for the association between c-MYC amplification and outcome showed statistically significant association between c-MYC amplification and incomplete remission in newly diagnosed AML patients with P-value = 0.013 and odds ratio (95% CI) of 14.0. Conclusion Our study has shown that c-MYC amplification is associated with adverse prognosis, poor treatment outcome and it might be involved in the process of AML progression. Targeting cMYC may be of value in the development of new-targeted AML therapeutics.