Prognostic assessment of the expression of genes involved in cholesterol metabolism in patients with Acute Myeloid Leukemia treated with intensive chemotherapy.

• Grant number: 24/11555-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2024
• End date: November 30, 2025
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Eduardo Magalhães Rego
• Grantee: Taina Shi
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Acute Myeloid Leukemia (AML) is the most prevalent bone marrow cancer in Brazil, presenting a significant and challenging health issue due to its broad clinical and molecular variability. This makes precise risk stratification essential for guiding appropriate treatment. Traditional therapies, which combine cytarabine and anthracyclines, remain predominant. However, the heterogeneity of AML and unexpected progression in many cases, particularly in intermediate-risk patients, complicate therapeutic decision-making. The International Consortium of Acute Myeloid Leukemias (ICAML2015), promoted by the American Society of Hematology (ASH), aims to improve survival rates for adult AML patients in the favorable and intermediate-risk groups by offering advanced methods for treatment selection and response monitoring. One of the strategies of ICAML2015 is to identify new prognostic markers to refine risk stratification and avoid unnecessary allogeneic stem cell transplants.Based on evaluations of various cohorts, our group proposed a four-gene prognostic index (4-PI) consisting of CYP2E1, DHCR7, IL2RA, and SQLE, which, when combined with the ELN categorization, has demonstrated effective prognostic prediction for AML and the potential to improve risk stratification. In this context, the present project aims to validate the prognostic relevance of the SQLE (squalene epoxidase) and DHCR7 (7-dehydrocholesterol reductase) genes, involved in cholesterol biosynthesis, in AML patients treated with intensive chemotherapy. Recent publications indicate that dysregulation of cholesterol biosynthesis enzymes results in cholesterol accumulation, which is associated with chemotherapy resistance.This project seeks to validate the prognostic value of SQLE and DHCR7 gene expression in AML patients treated with intensive chemotherapy, outside the context of controlled clinical trials. To achieve this, 120 AML patients treated with intensive chemotherapy and part of the ICAML2015 project will be included. Selection will follow rigorous inclusion criteria, with ethical approval from the Ethics Committee of the Instituto do Câncer do Estado de São Paulo (ICESP) and the Hospital das Clínicas of the Faculty of Medicine of the University of São Paulo. Informed consent will be obtained from all participants. Gene expression quantification of SQLE and DHCR7 will be performed using quantitative PCR (qPCR). RNA will be extracted using TRIzol", converted into cDNA, and gene expression will be measured using the Applied Biosystems" Power SYBR" Green PCR Master Mix. Expression will be normalized with reference genes (ACTB and GAPDH) and compared with Cq values.Subsequently, statistical analysis will classify patients into high and low gene expression groups based on cut-off values determined by ROC curves. Univariate and multivariate Cox regression analyses will be conducted, adjusting for sex, ELN2017 classification, age, and leukocyte count. The area under the ROC curve (AUC) will be calculated, and the Akaike Information Criterion (AIC) will be used to compare models. Outcomes evaluated will include overall survival, disease-free survival, event-free survival, and cumulative incidence of relapse. Kaplan-Meier curves and log-rank tests will be used for stratification evaluation, along with Mann-Whitney and chi-square tests to compare clinical and laboratory characteristics between groups. All analyses will be performed using R 4.1.1 software. This study has the potential to enhance risk stratification for AML patients and contribute to personalized treatment, improving prognosis and therapeutic response.