mRNA overexpression of BAALC: A novel prognostic factor for pediatric acute lymphoblastic leukemia

Acute lymphoblastic leukemia in children and SALL4 and BMI-1 gene expression

BACKGROUND

Sal-like protein 4 transcription factor (SALL4) and B cell-specific Moloney murine leukemia virus integration site 1 (BMI-1) gene were reported to cause treatment failure and relapse in several malignancies. We aimed to evaluate the prognostic value of SALL4 and BMI-1 in children with acute lymphoblastic leukemia (ALL).

METHODS

This prospective cohort study was carried out on 60 children with ALL as the patient group and 60 age- and sex-matched children as the control group. We evaluated the expression pattern of both SALL4 and BMI-1 genes in the peripheral blood using real-time reverse transcriptase-polymerase chain reaction in children with ALL at initial diagnosis before chemotherapy. We followed up with the patient group for 2 years for relapse or death.

RESULTS

Both SALL4 and BMI-1 were overexpressed in ALL children compared to the control group. Moreover, the expression of SALL4 and BMI-1 in patients with relapse was significantly higher than those with complete remission. The best cut-off of SALL4 and BMI-1 to predict relapse were >2.21 and 0.55 yielding sensitivity of 92.3% and 84.6%, respectively. Patients with overexpression of SALL4 and BMI-1 had significantly shorter overall and disease-free survival.

CONCLUSIONS

SALL4 and BMI-1 could be useful prognostic markers in children with ALL to predict relapse.

Novel gene signature reveals prognostic model in acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is a type of hematological malignancy and has a poor prognosis. In our study, we aimed to construct a prognostic model of ALL by identifying important genes closely related to ALL prognosis. We obtained transcriptome data (RNA-seq) of ALL samples from the GDC TARGET database and identified differentially expressed genes (DEGs) using the “DESeq” package of R software. We used univariate and multivariate cox regression analyses to screen out the prognostic genes of ALL. In our results, the risk score can be used as an independent prognostic factor to predict the prognosis of ALL patients [hazard ratio (HR) = 2.782, 95% CI = 1.903–4.068, p < 0.001]. Risk score in clinical parameters has high diagnostic sensitivity and specificity for predicting overall survival of ALL patients, and the area under curve (AUC) is 0.864 in the receiver operating characteristic (ROC) analysis results. Our study evaluated a potential prognostic signature with six genes and constructed a risk model significantly related to the prognosis of ALL patients. The results of this study can help clinicians to adjust the treatment plan and distinguish patients with good and poor prognosis for targeted treatment.

Study of mRNA of WT1, BAALC, EVI1, PRAME and HMGA2 genes in whole blood samples

Simultaneous quantitative measurement of mRNA of the WT1, BAALC, EVI1, PRAME and HMGA2 genes in whole blood samples reflects the specific pathological proliferative activity in acute leukemia and their ratio is promising as a diagnostic marker. The transcriptome profile of acute leukemia cells is usually assessed using NGS or microarray techniques after a preliminary procedure for isolation of mononuclear cells. However, the results of using the multiplex PCR reaction for the simultaneous determination of all above mRNAs in whole blood samples have not been published so far. Determination of mRNA of WT1, BAALC, EVI1, PRAME and HMGA2 genes in venous blood level samples by multiplex RT-PCR. The study included 127 blood samples from patients who diagnosis of acute leukemia was subsequently confirmed. In the comparison group, 87 samples of patients without oncohematological diagnosis were selected, including 31 samples (K1) with a normal blood formula and 56 samples (K2) with a violation of the cellular composition - anemia, leukocytosis and thrombocytopenia. RNA isolation and reverse transcription were performed using the Ribozol-D and Reverta-L kits (TsNIIE, Russia). Determination of the mRNA expression level of the WT1, BAALC, EVI1, PRAME and HMGA2 genes by multiplex real-time PCR using a homemade multiplex PCR kit. The mRNA level was characterized by high interindividual variation and did not correlate with the rate of circulating leukocytes or blood blasts. Expression of WT1 mRNA was observed in whole blood only in one patient from the control group and in 112 (88%) patients with leukemia and was combined with a decrease in the level of HMGA2 mRNA expression and BAALC mRNA values. In contrast to the control groups, patients with leukemia had higher levels of BAALC mRNA in AML and ALL, increased PRAME mRNA in AML and APL, but lower levels of HMGA2 in APL.

A Novel Role for Brain and Acute Leukemia Cytoplasmic (BAALC) in Human Breast Cancer Metastasis

Brain and Acute Leukemia, Cytoplasmic (BAALC) is a protein that controls leukemia cell proliferation, differentiation, and survival and is overexpressed in several cancer types. The gene is located in the chromosomal region 8q22.3, an area commonly amplified in breast cancer and associated with poor prognosis. However, the expression and potential role of BAALC in breast cancer has not widely been examined. This study investigates BAALC expression in human breast cancers with the aim of determining if it plays a role in the pathogenesis of the disease. BAALC protein expression was examined by immunohistochemistry in breast cancer, and matched lymph node and normal breast tissue samples. The effect of gene expression on overall survival (OS), disease-free and distant metastasis free survival (DMFS) was assessed in silico using the Kaplan-Meier Plotter (n=3,935), the TCGA invasive breast carcinoma (n=960) and GOBO (n=821) data sets. Functional effects of BAALC expression on breast cancer proliferation, migration and invasion were determined in vitro. We demonstrate herein that BAALC expression is progressively increased in primary and breast cancer metastases when compared to normal breast tissue. Increased BAALC mRNA is associated with a reduction in DMFS and disease-free survival, but not OS, in breast cancer patients, even when corrected for tumor grade. We show that overexpression of BAALC in MCF-7 breast cancer cells increases the proliferation, anchorage-independent growth, invasion, and migration capacity of these cells. Conversely, siRNA knockdown of BAALC expression in Hs578T breast cancer cells decreases proliferation, invasion and migration. We identify that this BAALC associated migration and invasion is mediated by focal adhesion kinase (FAK)-dependent signaling and is accompanied by an increase in matrix metalloproteinase (MMP)-9 but not MMP-2 activity in vitro. Our data demonstrate a novel function for BAALC in the control of breast cancer metastasis, offering a potential target for the generation of anti-cancer drugs to prevent breast cancer metastasis.

Simultaneous changes in expression levels of BAALC and miR-326: a novel prognostic biomarker for childhood ALL

OBJECTIVE

Multidrug resistance and consequent relapse are two major obstacles for treating children with acute lymphoblastic leukemia, the most frequent childhood malignancy. MicroRNAs have potential regulatory roles in response to chemotherapy. The goal of this study was to determine the microRNA that may have effects on the expression level of brain and acute lymphoblastic leukemia (BAALC) and to investigate the in vitro and ex vivo association between their expression levels.

METHODS

In silico tools were utilized to determine a putative miRNA targeting BALLC. Quantitative real-time polymerase chain reaction was used to investigate expression levels of BAALC and its predicted microRNA, miR-326, in bone marrow samples of 30 children with acute lymphoblastic leukemia and 13 controls, in addition to the resistant and parental CCRF-CEM cell lines. To assess the status of response to therapy, minimal residual disease was measured using single-strand conformation polymorphism.

RESULTS

MiR-326 was selected due to the strong possibility of its interaction with BAALC according to the obtained in silico results. Statistical analysis showed a significant downregulation of miR-326 and overexpression of BALLC in drug-resistant acute lymphoblastic leukemia cell line and patients compared with the parental cell line and drug-sensitive patients, respectively (P = 0.015, 0.005, 0.0484 and 0.0005, respectively). The expression profiles of miR-326 and BAALC were inversely correlated (P = 0.028).

CONCLUSIONS

The results introduced the inversely combined expression levels of miR-326 and BAALC as a novel, independent prognostic biomarker for pediatric acute lymphoblastic leukemia (P = 0.007). Moreover, bioinformatics data showed a possible regulatory role for miR-326 on BAALC mRNA, which may possibly contribute to the development of drug resistance in patients with childhood acute lymphoblastic leukemia.

Genetics of blood malignancies among Iranian population: an overview

BACKGROUND

Blood malignancies are among the leading causes of cancer related deaths in the world. Different environmental and genetic risk factors are involved in progression of blood malignancies. It has been shown that the lifestyle changes have affected the epidemiological patterns of these malignancies. Hematologic cancers are the 5th common cancer among Iranian population. It has been observed that there is a rising trend of blood malignancies incidences during the recent decades. Therefore, it is required to design novel diagnostic methods for the early detection of such malignancies in this population.

MAIN BODY

In present review we have summarized all of the significant genes which have been reported among Iranian patients with blood malignancies. The reported genes were categorized based on their cell and molecular functions to clarify the molecular biology and genetics of blood malignancies among Iranian patients.

CONCLUSION

It was observed that the epigenetic and immune response factors were the most frequent molecular processes associated with progression of blood malignancies among Iranian population. This review paves the way of introducing a population based panel of genetic markers for the early detection of blood malignancies in this population.

RUNX1 variant as a genetic predisposition factor for acute myeloid leukemia

Acute myeloid leukemia (AML) is the most common hematological malignancy among adults and is characterized by accumulation of immature myeloid cells. Different genetic factors have role in the occurrence of AML. Among different proteins, RUNX1 and BAALC are involved in the development AML. It has been shown that BAALC overexpression is a factor that indicate shorter disease free survival in a subset of AML patients. RUNX1 has been implicated in the development of breast, prostate, lung, and skin cancers. The aim of this study is determination of the prevalence of common polymorphisms in BAALC (rs6999622 and rs62527607) and RUNX1 (rs13051066 and rs61750222) in AML patients compared with healthy subjects. A total of 100 AML patients and 100 healthy control subjects were included in our study. Genomic DNA was isolated from peripheral blood and the polymorphisms were genotyped by applying ARMS and PCR-RFLP methods. Finally, data was analyzed using SPPSS software. Our results demonstrate a significant association between the RUNX1 rs13051066 and AML in the co-dominant (odd ratio = 6.66, 95% Cl = 1.85-25, p = .006) and dominant (GT + TT versus GG: odd ratio = 6.15, 95% CI = 1.73-21.87, p = .002) models. The RUNX1 rs13051066 polymorphism is associated with risk of AML in Iranian population. Future studies should consider larger sample size for assessment of RUNX1 gene polymorphisms, and employ cytogenetic and molecular analyses in AML patients from different ethnic origins.

Drug Resistance Biomarkers and Their Clinical Applications in Childhood Acute Lymphoblastic Leukemia

Biomarkers are biological molecules found in body fluids or tissues, which can be considered as indications of a normal or abnormal process, or of a condition or disease. There are various types of biomarkers based on their application and molecular alterations. Treatment-sensitivity or drug resistance biomarkers include prognostic and predictive molecules with utmost importance in selecting appropriate treatment protocols and improving survival rates. Acute lymphoblastic leukemia (ALL) is the most prevalent hematological malignancy diagnosed in children with nearly 80% cure rate. Despite the favorable survival rates of childhood ALL (chALL), resistance to chemotherapeutic agents and, as a consequence, a dismal prognosis develops in a significant number of patients. Therefore, there are urgent needs to have robust, sensitive, and disease-specific molecular prognostic and predictive biomarkers, which could allow better risk classification and then better clinical results. In this article, we review the currently known drug resistance biomarkers, including somatic or germ line nucleic acids, epigenetic alterations, protein expressions and metabolic variations. Moreover, biomarkers with potential clinical applications are discussed.

MicroRNA-326 and microRNA-200c: Two novel biomarkers for diagnosis and prognosis of pediatric acute lymphoblastic leukemia

Multidrug resistance (MDR) is considered as the major obstacle for treating pediatric acute lymphoblastic leukemia (ALL). MicroRNAs (miRNAs) are small non coding RNAs which may potentially regulate response to chemotherapy. In this study, total RNA was isolated from bone marrow samples of 46 children with de novo ALL and 16 controls. Quantitative reverse transcriptase polymerase chain reaction was used to investigate the expression profile of the predicted miRNAs; miR-326 and miR-200c, and their predicted targets ABCA2, and ABCA3 transporters. The presence of minimal residual disease was studied using PCR-SSCP (single-strand conformation polymorphism) 1 year after treatment. The association between the miRNA expression and drug resistance was analyzed statistically. Results showed a significant down-regulation of both miR-326 and miR-200c expressions in ALL patients compared with non-cancer controls (P = 0.0002, AUC = 0.813 and P = 0.035, AUC = 0.79, respectively). A considerable negative association between miR-326 expression and MDR was identified which could raise the risk of chemoresistance by 4.8- fold. The expression profiles of miR-326 and ABCA2 transporter were inversely correlated. Data revealed, a novel diagnostic role for miR-326 and miR-200c as potential biomarkers of pediatric ALL. Down-regulation of miR-326 was introduced, for the first time, as a prognostic factor for drug resistance in childhood ALL. To the best of our knowledge, this is the first time that ABCA2 transporter is proposed as a target gene for miR-326, through which it can exert its impact on drug resistance. These data may provide novel approaches to new therapeutics and diagnostics.

Evaluation of BAALC gene expression in normal cytogenetic acute myeloid leukemia patients in north-east of Iran

Background: Acute myeloid leukemia (AML) is known as one of the most common leukemia among adults. Environmental and different genetic factors affect disease process, prognosis and treatment. Among different genetic factors NPM1, FLT3, MLL and BAALC genes are the most effective on patient's survival rate. The aim of this study was to assess amount of BAALC gene expression in AML patients, and its relation to survival rate. Methods: In this case-control study, from all 94 individuals referred to Ghaem Medical Center during 2012-2015, 47 cases were normal cytogenetic AML and others were healthy individuals that were studied as control group. Real-time PCR method was applied for gene expression evaluation. Other information of patients was extracted from medical documents. SPSS v.21 was used for data processing. Results: Mean age of studied cases was 31.50 years. The most of BAALC gene expression was seen in M1 and M2 subtypes, and the less was in M5. A significant relation was found between amount of gene expression and patient's survival rate. Conclusion: BAALC gene expression was increased significantly in AML cases. BAALC expression had reverse relation with patients' survival rate in North-East of Iran.