Selection of three miRNA signatures with prognostic value in non-M3 acute myeloid leukemia

Construction of a solid Cox model for AML patients based on multiomics bioinformatic analysis

Acute myeloid leukemia (AML) is a highly heterogeneous hematological malignancy. The bone marrow (BM) microenvironment in AML plays an important role in leukemogenesis, drug resistance and leukemia relapse. In this study, we aimed to identify reliable immune-related biomarkers for AML prognosis by multiomics analysis. We obtained expression profiles from The Cancer Genome Atlas (TCGA) database and constructed a LASSO-Cox regression model to predict the prognosis of AML using multiomics bioinformatic analysis data. This was followed by independent validation of the model in the GSE106291 (n=251) data set and mutated genes in clinical samples for predicting overall survival (OS). Molecular docking was performed to predict the most optimal ligands to the genes in prognostic model. The single-cell RNA sequence dataset GSE116256 was used to clarify the expression of the hub genes in different immune cell types. According to their significant differences in immune gene signatures and survival trends, we concluded that the immune infiltration-lacking subtype (IL type) is associated with better prognosis than the immune infiltration-rich subtype (IR type). Using the LASSO model, we built a classifier based on 5 hub genes to predict the prognosis of AML (risk score = -0.086×ADAMTS3 + 0.180×CD52 + 0.472×CLCN5 - 0.356×HAL + 0.368×ICAM3). In summary, we constructed a prognostic model of AML using integrated multiomics bioinformatic analysis that could serve as a therapeutic classifier.

Clinical Applications of MicroRNAs in Acute Myeloid Leukemia: A Mini-Review

MicroRNAs (miRs) are short non-coding RNAs, typically 18-25 nucleotides in length, that are critically important, through their direct effects on target mRNAs, in a variety of cellular processes including cell differentiation, proliferation and survival. Dysregulated miR expression has been identified in numerous cancer types including acute myeloid leukemia (AML). From a clinical standpoint, several miRs have been shown to associate with prognosis in AML patients. Furthermore, they also carry the potential to be used as biomarkers and to inform medical decision making. In addition, several preclinical studies have provided strong rationale to develop novel therapeutic strategies to target miRs in AML. This review will focus on potential clinical applications of miRs in adult AML and will discuss unique miR signatures in specific AML subtypes, their role in prognostication and response to therapy, as well as miRs that are promising therapeutic targets and ongoing clinical trials directed towards targeting clinically relevant miRs in AML that could allow for improvements in current treatment strategies.

Microarray analysis of differentially expressed microRNAs in myelodysplastic syndromes

BACKGROUND

Our study aimed to analyze differential microRNA expression between myelodysplastic syndromes (MDS) and normal bone marrow, and to identify novel microRNAs relevant to MDS pathogenesis.

METHODS

MiRNA microarray analysis was used to profile microRNA expression levels in MDS and normal bone marrow. Quantitative real-time polymerase chain reaction was employed to verify differentially expressed microRNAs.

RESULTS

MiRNA microarray analysis showed 96 significantly upregulated (eg, miR-146a-5p, miR-151a-3p, miR-125b-5p) and 198 significantly downregulated (eg, miR-181a-2-3p, miR-124-3p, miR-550a-3p) microRNAs in MDS compared with normal bone marrow. The quantitative real-time polymerase chain reaction confirmed the microarray analysis: expression of six microRNAs (miR-155-5p, miR-146a-5p, miR-151a-3p, miR-221-3p, miR-125b-5p, and miR-10a-5p) was significantly higher in MDS, while 3 microRNAs (miR-181a-2-3p, miR-124-3p, and miR-550a-3p) were significantly downregulated in MDS. Bioinformatics analysis demonstrated that differentially expressed microRNAs might participate in MDS pathogenesis by regulating hematopoiesis, leukocyte migration, leukocyte apoptotic process, and hematopoietic cell lineage.

CONCLUSIONS

Our study indicates that differentially expressed microRNAs might play a key role in MDS pathogenesis by regulating potential relevant functional and signaling pathways. Targeting these microRNAs may provide new treatment modalities for MDS.

miR-744-5p Inhibits Non-Small Cell Lung Cancer Proliferation and Invasion by Directly Targeting PAX2

Non-small cell lung cancer is one of the leading causes of cancer-related death worldwide. MicroRNAs have been characterized as critical regulators for cancer progression including non-small cell lung cancer. This work explored microRNA-744-5p expression in non-small cell lung cancer cell lines and normal cell line using quantitative real-time polymerase chain reaction. Connection of microRNA-744-5p and paired box 2 was analyzed with bioinformatic analysis, luciferase activity reporter assay, and Western blot. Effects of microRNA-744-5p or paired box 2 expression on non-small cell lung cancer cell behaviors were analyzed using a series of in vitro experiments. MicroRNA-744-5p was found to have decreased expression in non-small cell lung cancer cell lines compared with normal cell line. Paired box 2 was identified as a direct target for microRNA-744-5p in non-small cell lung cancer. Overexpression of microRNA-744-5p inhibits non-small cell lung cancer cell proliferation, colony formation, and cell invasion in vitro through targeting paired box 2. The present study provided novel insights into the biological functions of microRNA-744-5p in non-small cell lung cancer.

miR‑21 inhibits autophagy and promotes malignant development in the bladder cancer T24 cell line

MicroRNA‑21 (miR‑21) is reported to exhibit cancer‑promoting activity in various types of cancer. It has been previously demonstrated that miR‑21 is overexpressed in bladder tumor tissue compared with normal mucosa. However, the functional mechanism of miR‑21 in bladder cancer remains largely unknown. Thus, the current study aimed to determine the roles of miR‑21 in autophagy and the malignant development of bladder cancer in T24 cells. Upregulation or downregulation of miR‑21 was achieved following the transfection of miR‑21 mimic or miR‑21 inhibitor. An MTT assay was additionally performed to measure cell growth. Wound healing and transwell invasion assays were used to detect cell migration and invasion. The apoptotic potential and cell cycle were examined via flow cytometry and reverse transcription‑quantitative PCR was performed to evaluate the expression of phosphatase and tensin homolog (PTEN), beclin 1, microtubule‑associated protein l light chain 3B (LC3‑II), cyclin D1, caspase‑3, E‑cadherin, matrix metallopeptidase‑9 (MMP‑9) and vimentin. The results revealed that the proliferation, migration and invasion of T24 cells was greatly increased in the miR‑21 mimic group, while apoptosis was greatly inhibited. Additionally, T24 cells treated with miR‑21 mimic exhibited G1‑phase arrest. In the miR‑21 mimic group, the expression of PTEN, beclin 1, LC3‑II, caspase‑3 and E‑cadherin were decreased, while the expression of cyclin D1, MMP‑9 and vimentin were increased. Opposite effects were observed in the miR‑21 inhibitor group. The data of the current study may indicate that miR‑21 overexpression inhibited autophagy and promoted the proliferation, migration, invasion and epithelial to mesenchymal transition of bladder cancer T24 cells. The results may further elucidate the molecular mechanism of miR‑21 in the development of bladder cancer.