Characterizing Iranian Pediatric Patients With Relapsed Acute Lymphoblastic Leukemia Through Gene Expression Profiling of Common ATP Binding Cassette Transporters Subfamily C.

BACKGROUND: The correlation between gene expression of ABCC transporters and recurrence as a treatment failure in pediatric patients with acute lymphoblastic leukemia (ALL) is an unsolved problem in scientific associations. The aim of this study was to evaluate the predictive value of ABCC1-6 gene expression pattern for estimating recurrence in Iranian pediatric patients with ALL. MATERIALS AND METHODS: Iranian pediatric patients with approved ALL enrolled in this study as 2 groups of case (relapsed ALL) and control (treated individuals who lasted for >3 years following their final treatment). Real-time polymerase chain reaction was done with GAPDH for expressing ABCC1-6 transporter genes. Cumulative doses of Vincristine, Daunorubicin, and L-Asparginase were checked for each patient. Gathered data analyzed with SPSS version 22 and REST 2009 software. RESULTS: Thirty-nine samples as 23 relapsed ALL and 16 controls enrolled. High expression of ABCC2-6 and low expression of ABCC1 were detected in pediatric patients with relapse. ABCC3 and ABCC4 had significant relation with high-risk patients of NCI group. Also, ABCC4 and ABCC6 had more expression with high doses of Daunorubicin and L-Asparginase. CONCLUSIONS: Designed expression pattern have the predictive value for estimating of conferring relapse in Iranian pediatric patients with diagnosed ALL. The authors suggest of designing a multiple childhood malignancy center project to evaluate this pattern in a cohort study.

Pattern of ABCC Transporter Gene Expression in Pediatric Patients with Relapsed Acute Lymphoblastic Leukemia.

BACKGROUND: Abnormal expression of ABCC transporter genes has been associated with treatment failure in pediatric patients with acute lymphoblastic leukemia (ALL). The aim of this study was to evaluate the expression pattern of ABCC1-6 and ABCC10 genes in Iranian pediatric patients with ALL relapse and determine the potential predictive value of determining ALL relapse from ABCC expression. METHODS: Patients with ALL were divided into two separate groups, either the case group with relapsed ALL or the control group in which ALL patients have been in progression-free survival for at least 3 years A total of thirty-nine participants (23 with relapsed ALL; 16 controls) were enrolled over 26 months. To determine the levels of ABCC1-6 and ABCC10 transporter gene expression RT-PCR was used. Cumulative doses of the chemotherapy drugs, VCR, DNR and L-ASP, were calculated for each patient. RESULTS: Our findings showed elevated expression of ABCC2-6 and decreased expression of ABCC1 and ABCC10 to be associated with an increased risk of ALL relapse. The mean-fold expression of ABCC2 was significantly increased in the ALL relapse group. Additionally, the expression pattern of the ABCC transporter genes was associated with high doses of three chemotherapy drugs, VCR, DNR and L-ASP. CONCLUSION: Evaluating the expression pattern of ABCC transporter genes may be a potential biomarker for predicting the occurrence of ALL relapse in Iranian pediatric patients and improve cancer prognosis.

ATP-Binding Cassette transporters' gene expression in pediatric patients with acute leukemia; a comprehensive analysis of published reports through PubMed search engine.

Multidrug resistance based on ABC transporters' gene expression is one of the most important health challenges through chemotherapy of patients. This resistance can cause relapse or treatment failure. The goal of this conducted study was to evaluate the results of published reports which considered ABC transporters' gene expression in pediatric patients with acute leukemia. PubMed as a free search engine was chosen. The following Mesh terms were used as: "ATP-binding cassette transporters" OR "ABC-transporters*" AND "gene expression*" AND "leukemia" OR "ALL" OR "AML" OR "acute leukemia*". Age was set as an additional filter with the age range of birth to 18 years old. Initial screening was performed according to inclusion and exclusion criteria and the quality of the selected papers was assessed. Papers categorized into three sections as: pediatric patients with ALL (6 papers from 1998-2015); pediatric patients with AML (3 papers from 1992-2011) and pediatric patients with ALL and AML (7 papers from 1992-2014). Totally 1118 patients enrolled in the searched studies (ALL and AML: 488; ALL: 405; AML: 225). The common method for evaluating gene expression of ABC transporters was RT-PCR. More than 50% of the papers showed the influence of ABC transporters' gene expression on prognosis and treatment failures of patients. Despite controversial results, the gathered information in the current report serves as a comprehensive referential resource, which can be beneficial for future planning around this title, especially in developing countries.