Validação de um painel molecular para detecção de alterações genéticas em pacientes portadores de leucemias agudas no estado do Ceará

Abstract

Leukemia is one of the most common types of cancer involving adult and pediatric pa tients worldwide, and its distribution may be associated with a wide range of factors such as socioeconomic s tatus, o ccupational factors, and ethnicit y . In the St ate of Cear á, there is no molecular diagnosis to detect the various genetic subtypes that dete rmine the diagnosis, prognosis and target directed therapy in individuals treated in health services. This in creases the costs of hospitalization and/ o r clinical/ surgical tr eatment, and results in a worse prognosis for these patients. In addition, the Stat e of Ceará is one of the states in Brazil with the highest rate of leukemia cases according to data from the Nationa l Cancer Institute (2023). Th is da ta may be r elated to e xposure to occupational factors or even to intrinsic genetic factors of this popula tion. In this context, the study aims to characterize the Ceará population affected by acute leukemias thr ough an evaluation of clinical epidemiolog ica l data a nd expressi on of the main genetic biomarkers related to the disease described in the literatur e: BCR::ABL1 (p190+), ETV6::RUNX1, TCF3::P BX1, SIL::TAL1 , KMT2A::AFF1, CBFB::MYH11, PML::RARA, RUNX1::RUNX 1T1 and FLT3 ITD . The search for these ma rker s was p erformed us ing Nested PCR and RT qPCR techniques, in order to compare both tests sensitivity . In addition, in view of the absence of studies on the best reference gene for the analy sis of p ati ents with acute leukemia, a pane l of genes commonly used as endogenous for stability analysis was selected from the literature: GAPDH, AB L, HPRT1, RPLPO, ACTB and TBP . Over all, there was a sample of 117 patients who were stratified according to t he guide lin es of the European Leukemia Net and the Wor ld Health Org anization. Patients were classified based on type of leukemia, age, gender, origi n, laboratory parameters, risk, occupation, and outcome. For the statistical analysis based on patients clinical and epid emi ological data , t he Chi squa re test was a pplied, ass uming a significance level of 95% (p≤0.05). After all the analyses, it was possible to identify that the study participants were predominantly male and had a mea n age of 47 .3 years. The study was also abl e to establ ish the best set of endogenous drugs to b e used in expression assays with samples from patient s with acute leukemias: ACTB, ABL, TBP and RPLPO . In addition, the genetic alterations BCR::ABL1, TCF3::P BX 1, CBFB: CBFB::MY H11, PML::RARA, RUNX1::RUNX1T1 a nd FLT3 ITD were detecte d through the two diagnostic techniques used, but it was observed that the sensit ivity of RT qPCR was considerably higher when compared to Nested PCR.