Prognostic significance of lymphoid enhancer-binding factor-1 expression in egyptian adult B-acute lymphocytic leukemia patients

Circulating Biomarkers Associated with the Diagnosis and Prognosis of B-Cell Progenitor Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) is a hematological disease characterized by the dysfunction of the hematopoietic system that leads to arrest at a specific stage of stem cells development, suppressing the average production of cellular hematologic components. BCP-ALL is a neoplasm of the B-cell lineage progenitor. BCP-ALL is caused and perpetuated by several mechanisms that provide the disease with its tumor potential and genetic and cytological characteristics. These pathological features are used for diagnosis and the prognostication of BCP-ALL. However, most of these paraclinical tools can only be obtained by bone marrow aspiration, which, as it is an invasive study, can delay the diagnosis and follow-up of the disease, in addition to the anesthetic risk it entails for pediatric patients. For this reason, it is crucial to find noninvasive and accessible ways to supply information concerning diagnosis, prognosis, and the monitoring of the disease, such as circulating biomarkers. In oncology, a biomarker is any measurable indicator that demonstrates the presence of malignancy, tumoral behavior, prognosis, or responses to treatments. This review summarizes circulating molecules associated with BCP-ALL with potential diagnostic value, classificatory capacity during monitoring specific clinic features of the disease, and/or capacity to identify each BCP-ALL stage regarding its evolution and outcome of the patients with BCP-ALL. In the same way, we provide and classify biomarkers that may be used in further studies focused on clinical approaches or therapeutic target identification for BCP-ALL.

Prognostic evidence of LEF1 isoforms in childhood acute lymphoblastic leukemia

INTRODUCTION

The lymphoid enhancer factor 1 (LEF1) is a DNA-binding transcription factor that functions in the Wnt signaling pathway. Increased LEF1 activity is associated with progression of several types of cancer including leukemia. Here, we investigated LEF1 isoform expression and genomic variations in acute lymphoblastic leukemia (ALL).

METHODS

LEF1 isoform expression was evaluated by quantitative real-time PCR in 87 newly diagnosed childhood ALL patients and controls. Moreover, Western blot analysis was performed for detection of LEF1 expression and the hotspot region of LEF1 was screened by deep sequencing.

RESULTS

The LEF1 mRNA expression of B cell ALL patients was higher than the controls (LEF1-total P = .011, LEF1-long P = .026). Moreover, B-ALL samples showing higher total LEF1 expression had significantly shorter relapse-free survival (P = .008) and overall survival (P = .011). Although full-length LEF1 expression was similar to the controls in T-ALL, 50% (n = 15) of the ALL patients had increased full-length LEF1 protein expression. Imbalance between short- and full-length LEF1 isoforms may lead to cell survival in ALL. Beside the LEF1 activation, LEF1 gene variations were rarely observed in our cohort.

CONCLUSION

The results indicate that the Wnt pathway may have a pathogenic function in a group of ALL patients and high LEF1-total expression might be a marker for shorter relapse-free survival time in B cell ALL.

Lymphoid enhancer-binding factor 1 (LEF-1): a favorable prognostic factor in adult acute myeloid leukemia in Egyptian patients

Background

Canonical wingless-type (Wnt) signaling is a crucial pathway involved in normal hematopoiesis and the self-renewal process of hematopoietic stem cells. Deregulation of this pathway has been associated with different subtypes of leukemia. Lymphoid enhancer-binding factor 1 (LEF-1) is a major transcription factor of this pathway and plays a pivotal role in lymphoid differentiation and granulopoiesis. High LEF-1 expression has been reported as a prognostic marker in several types of adult hematological malignancies. We aimed to assess the prognostic utility of LEF-1 expression in adult de novo acute myeloid leukemia (AML) Egyptian patients in continuation of our previous work. LEF-1 expression was analyzed by real-time polymerase chain reaction (PCR) in 30 adults with newly diagnosed AML and remeasured at day 28 after induction therapy with the assessment of remission status.

Results

Patients were classified according to median expression level into high and low LEF-1 expression groups. LEF-1 levels were dramatically decreased following successful induction therapy. Also, high LEF-1 expression patients had a better response to therapy with better overall survival. ROC curve analysis of LEF-1 expression yielded a cutoff value of < 10.11 log10 (sensitivity of 90.48% and specificity of 100%) for predicting poor outcome. Univariate logistic regression analysis showed that for every log10 increase in the LEF-1 expression level, the chance of the patient to achieve hematological remission was increased by 2.29 folds.

Conclusion

Our study showed preliminary results that overexpression of LEF-1 is a favorable prognostic factor in newly diagnosed adult AML patients. The prognostic value of LEF-1 could suggest its utility for further risk classifications of AML and potentiality for being a target for therapy.

The multiple ways Wnt signaling contributes to acute leukemia pathogenesis

WNT proteins constitute a very conserved family of secreted glycoproteins that act as short-range ligands for signaling with critical roles in hematopoiesis, embryonic development, and tissue homeostasis. These proteins transduce signals via the canonical pathway, which is β-catenin-mediated and better-characterized, or via more diverse noncanonical pathways that are β-catenin independent and comprise the planar cell polarity (PCP) pathway and the WNT/Ca⁺⁺ pathways. Several proteins regulate Wnt signaling through a variety of sophisticated mechanisms. Disorders within the pathway can contribute to various human diseases, and the dysregulation of Wnt pathways by different molecular mechanisms is implicated in the pathogenesis of many types of cancer, including the hematological malignancies. The types of leukemia differ considerably and can be subdivided into chronic, myeloid or lymphocytic, and acute, myeloid or lymphocytic, leukemia, according to the differentiation stage of the predominant cells, the progenitor lineage, the diagnostic age strata, and the specific molecular drivers behind their development. Here, we review the role of Wnt signaling in normal hematopoiesis and discuss in detail the multiple ways canonical Wnt signaling can be dysregulated in acute leukemia, including alterations in gene expression and protein levels, epigenetic regulation, and mutations. Furthermore, we highlight the different impacts of these alterations, considering the distinct forms of the disease, and the therapeutic potential of targeting Wnt signaling.

RETRACTED: LEF-1 gene silencing inhibits pulmonary vascular remodeling and occurrence of pulmonary arterial hypertension through the β-catenin signaling pathway

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the authors as the validity of the pulmonary vascular remodeling indicators cannot be guaranteed. The authors tried post publication to reproduce the results of the cell proliferation and cell aging, however they were not able to confirm the data that was presented by the article.

The anti-apoptotic PON2 protein is Wnt/β-catenin-regulated and correlates with radiotherapy resistance in OSCC patients

Aberrant Wnt signaling and control of anti-apoptotic mechanisms are pivotal features in different types of cancer to undergo cell death programs. The intracellular human enzyme Paraoxonase-2 (PON2) is known to have anti-apoptotic properties in leukemia and oral squamous cell cancer (OSCC) cells. However, the distinct regulating pathways are poorly understood. First, we present a so far unknown regulation of PON2 protein expression through the Wnt/GSK3β/β-catenin pathway in leukemia and OSCC cells. This was confirmed via in silico analysis, promoter reporter studies and treatment of multiple cell lines (K562, SCC-4, PCI-13) with different Wnt ligands/inhibitors in vitro. Ex vivo analysis of OSCC patients revealed a correlation between PON2 and β-catenin expression in tumor tissue. Higher PON2 expression in OSCC is associated with relapse independently of treatment (e.g. surgery/radio-/chemotherapy). These results emphasize the clinical impact of the newly described regulation of PON2 through Wnt/GSK3β/β-catenin. More importantly, the study revealed the fundamental finding of an overall Wnt/GSK3β/β-catenin dependent regulation of PON2 in different cancers, which was confirmed by systematic and multimethodological approaches. Thus, the herein presented mechanistic insight contributes to a better understanding of tumor specific escape from cell death strategies and suggests PON2 as a new potential biomarker for therapy resistance or as a prognostic tumor marker.