Interaction between 12p chromosomal abnormalities and Lnc-HOTAIR mediated pathway in acute myeloid leukemia

miR-133a and miR-135a Regulate All-Trans Retinoic Acid-Mediated Differentiation in Pediatric Acute Myeloid Leukemia by Inhibiting CDX2 Translation and Serve as Prognostic Biomarkers

Background: Acute myeloid leukemia (AML) is a type of blood cancer characterized by excessive growth of immature myeloid cells. Unfortunately, the prognosis of pediatric AML remains unfavorable. It is imperative to further our understanding of the mechanisms underlying leukemogenesis and explore innovative therapeutic approaches to enhance overall disease outcomes for patients with this condition. Methods: Quantitative reverse-transcription PCR was used to quantify the expression levels of microRNA (miR)-133a and miR-135a in 68 samples from 59 pediatric patients with AML. Dual-luciferase reporter transfection assay, Cell Counting Kit-8 assay, and western blot analysis were used to investigate the functions of miR-133a and miR-135a. Results: Our study found that all-trans-retinoic acid (ATRA) promoted the expression of miR-133a and miR-135a in AML cells, inhibited caudal type homeobox 2 (CDX2) expression, and subsequently inhibited the proliferation of AML cells. Additionally, miR-133a and miR-135a were highly expressed in patients with complete remission and those with better survival. Conclusions: miR-133a and miR-135a may play an antioncogenic role in pediatric AML through the ATRA-miRNA133a/135a-CDX2 pathway. They hold promise as potentially favorable prognostic indicators and novel therapeutic targets for pediatric AML.

miRNAs: novel noninvasive biomarkers as diagnostic and prognostic tools in neonatal sepsis

The study aimed to assess the diagnostic and prognostic value of 3 specific microRNAs (miRNAs) in early-onset neonatal sepsis (NS). We examined miR-1, miR-124, and miR-34a in 70 NS patients upon admission and compared them to 70 healthy controls by RT-PCR. The main finding of the study was the difference in miRNA expression levels between NS patients and controls. Higher expression levels of miR-1 and miR-124 were significantly associated with NS, while miR-34a expression was reduced. Among the studied miRNAs, miR-34a exhibited the highest specificity (97%) as a confirmatory test for NS. In the multivariate model, miR-1 and miR-124 were found to be significant predictors of disease progression or mortality. Overall, the study suggests that miR-1, miR-124, and miR-34a could serve as potential biomarkers for diagnosing and predicting outcomes in early-onset NS.

Cytogenetics analysis as the central point of genetic testing in acute myeloid leukemia (AML): a laboratory perspective for clinical applications

Chromosomal abnormalities in acute myeloid leukemia (AML) have significantly contributed to scientific understanding of its molecular pathogenesis, which has aided in the development of therapeutic strategies and enhanced management of AML patients. The diagnosis, prognosis and treatment of AML have also rapidly transformed in recent years, improving initial response to treatment, remission rates, risk stratification and overall survival. Hundreds of rare chromosomal abnormalities in AML have been discovered thus far using chromosomal analysis and next-generation sequencing. As a result, the World Health Organization (WHO) has categorized AML into subgroups based on genetic, genomic and molecular characteristics, to complement the existing French-American classification which is solely based on morphology. In this review, we aim to highlight the most clinically relevant chromosomal aberrations in AML together with the technologies employed to detect these aberrations in laboratory settings.

Upregulation of leukemia-induced non-coding activator RNA (LUNAR1) predicts poor outcome in pediatric T-acute lymphoblastic leukemia

T-cell Acute Lymphoblastic Leukemia (T-ALL) accounts for around 10-15% of all lymphoblastic leukemia in children. Previous studies have proven that dysregulation of Leukemia-induced non-coding activator RNA-1 (LUNAR1) expression promotes T-ALL cell growth by enhancing the NOTCH1/IGF-1R signaling pathway. We aimed to investigate the prognostic value of LUNAR1 in pediatric T-ALL, in addition, to find out its association with NOTCH1 and IGF-1R. The LUNAR1, NOTCH1, and IGF-IR gene expression were measured in peripheral blood (PB) samples of l85 children with T-ALL and forty non-leukemic samples as a control group. Cox regression analysis revealed that overexpression of LUNAR1, NOTCH1, and IGF-IR was significantly correlated with poor prognosis, short overall survival, and progression-free survival. We concluded that LUNAR1 could serve as an independent prognostic biomarker for T-ALL in children.

Long non-coding RNA HOTAIR regulates myeloid differentiation through the upregulation of p21 via miR-17-5p in acute myeloid leukaemia

Long non-coding RNA HOTAIR has been reported to play a key role in regulating various biological processes in various cancers. However, the roles and mechanisms of HOTAIR in acute myeloid leukaemia (AML) are still unclear and need to be investigated. In this study, we induced differentiation of four AML cell lines by all-trans retinoic acid (ATRA) and found HOTAIR was significantly upregulated in the process. Chromatin immunoprecipitation (ChIP) assays indicated that C/EBPβ upregulated HOTAIR during ATRA induced differentiation in HL-60 cells. By gain- and loss-of-function analysis, we then observed that HOTAIR expression was positively correlated with ATRA-induced differentiation and negatively regulated G1 phase arrest in HL-60 cells. In addition, we found that HOTAIR promoted ATRA-induced differentiation via the regulation of the cell cycle regulator p21 via miR-17-5p. Moreover, we detected the expression of HOTAIR in 84 de novo AML patients, HOTAIR was found significantly downregulated in the AML patients compared to the iron deficiency anaemia (IDA) control group, negatively correlated with the platelet level in M2 patients. In all, our data suggest that HOTAIR may be subtype-specific in AML-M2 patients, also HOTAIR regulates AML differentiation by C/EBPBβ/HOTAIR/miR-17-5p/p21 pathway. The findings of the present study provide a novel insight into the mechanism of lncRNA-mediated differentiation and indicate that HOTAIR may be a promising therapeutic target for leukaemia, especially for AML with M2 type.Abbreviation: AML: acute myeloid leukaemia; APL: acute promyelocytic leukaemia; ATRA: all-trans retinoic acid; CCK8: cell Counting Kit-8; CDKs: cyclin-dependent kinases ; CeRNA: competing endogenous RNAs; ChIP: chromatin immunoprecipitation; CHX: cycloheximide; FAB: French-American-British; FCM: flow cytometry; HOTAIR: HOX transcript antisense RNA; IDA: iron-deficiency anemia; lncRNA: long non-coding RNA; 3'UTR: 3'untranslated region; MT: Mutation type; WT: Wild type; qRT-PCR: Quantitative real-time PCR.

Uncommon cytogenetic abnormalities identifying high-risk acute myeloid leukemia in children

Pediatric acute myeloid leukemia (AML) represents an aggressive disease and is the leading cause of childhood leukemic mortality. The genomic landscape of pediatric AML has been recently mapped and redefined thanks to large-scale sequencing efforts. Today, understanding how to incorporate the growing list of genetic lesions into a risk stratification algorithm for pediatric AML is increasingly challenging given the uncertainty regarding the prognostic impact of rare lesions. Here we review some uncommon cytogenetic lesions to be considered for inclusion in the high-risk groups of the next pediatric AML treatment protocols. We describe their main clinical characteristics, biological background and outcome. We also provide some suggestions for the management of these rare but challenging patients and some novel targeted therapeutic options.

Long Noncoding RNA HOTAIR Contributes to Progression in Hepatocellular Carcinoma by Sponging miR-217-5p

Background: Hepatocellular carcinoma (HCC) is an aggressive primary hepatic cancer with high malignancy and poor prognosis. Long noncoding RNA HOTAIR has been classified as an oncogene to accelerate cell proliferation, migration, and invasion in many cancer types by interacting with the miRNA. Therefore, we assumed that HOTAIR might participate in HCC cell progression by interacting with miR-217-5p expression. Materials and Methods: The expression of HOTAIR and miR-217-5p in 35 HCC patients and HCC cells was measured by quantitative real-time polymerase chain reaction. Cell transfection was conducted using Lipofectamine 2000 transfection reagent. CCK8 and flow cytometry was applied for the measurement of cell proliferation and apoptosis. Cell migration and invasion capacities were carried out by transwell assay. Xenograft mice were constructed by subcutaneously injecting of stably transfected Huh-7 cells in mice. The interaction between HOTAIR and miR-217-5p was determined by luciferase reporter system. Protein expression of P13K, p-P13K, AKT, p-AKT, MMP-2, and MMP-9 was analyzed using Western blot assay. Results: The expression of HOTAIR was upregulated, whereas miR-217-5p was downregulated in HCC tumor tissues and cell lines (Hep3B and Huh-7) compared with normal tissues and human normal liver cell line MIHA. In addition, HOTAIR expression was negatively correlated with miR-217-5p expression in HCC (r² = 0.1867, p = 0.0171). More importantly, HOTAIR knockdown induced apoptosis and inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). In vivo experiments revealed that the interference of HOTAIR inhibited tumor growth. Subsequently, luciferase reporter system confirmed the interaction between HOTAIR and miR-217-5p. The rescue experiments clarified that miR-217-5p inhibitor attenuated the suppression of HOTAIR silencing on HCC cell proliferation, migration, invasion, and EMT. Furthermore, miR-217-5p inhibitor restored the inhibition of HOTAIR silencing mediated p-PI3K/p-AKT/MMP-2/9 protein expression. Conclusions: HOTAIR contributes to cell progression in HCC by sponging miR-217-5p, representing promising biomarkers for HCC treatment.