MicroRNA-1253 Regulation of WASF2 (WAVE2) and its Relevance to Racial Health Disparities

Hypomethylation-mediated upregulation of the WASF2 promoter region correlates with poor clinical outcomes in hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is one of the most common and lethal cancers worldwide. Wiskott–Aldrich syndrome protein family member 2 (WASF2) is an integral member of the actin cytoskeleton pathway, which plays a crucial role in cell motility. In this study, we aimed to explore the role of WASF2 in HCC carcinogenesis and its regulatory mechanism.

Methods

WASF2 expression in HCC was analyzed using six public RNA-seq datasets and 66 paired tissues from patients with HCC. The role of WASF2 in normal hepatocyte cell phenotypes was evaluated using a WASF2 overexpression vector in vitro; it was evaluated in HCC cell phenotypes using small interfering RNA (siRNA) in vitro and in vivo. Epigenetic regulatory mechanism of WASF2 was assessed in the Cancer Genome Atlas liver hepatocellular carcinoma project (TCGA_LIHC) dataset and also validated in 38 paired HCC tissues. Site mutagenesis, bisulfite sequencing polymerase chain reaction (BSP), methylation-specific polymerase chain reaction (MSP), and quantitative MSP (qMSP) were used for evaluating WASF2 methylation status.

Results

WASF2 is overexpressed in HCC and is clinically correlated with its prognosis. WASF2 overexpression promoted normal hepatocyte proliferation. WASF2 inactivation decreased the viability, growth, proliferation, migration, and invasion of Huh-7 and SNU475 HCC cells by inducing G2/M phase arrest. This induced cell death and inhibited epithelial–mesenchymal transition, hindering actin polymerization. In addition, WASF2 knockdown using siWASF2 in a xenograft mouse model and a lung metastasis model exerted tumor suppressive effect. There was a negative correlation between WASF2 methylation status and mRNA expression. The methylation pattern of CpG site 2 (− 726 bp), located in the WASF2 promoter, plays an important role in the regulation of WASF2 expression. Furthermore, the cg242579 CpG island in the WASF2 5′ promoter region was hypomethylated in HCC compared to that in the matched non-tumor samples. Patients with high WASF2 methylation and low WASF2 expression displayed the highest overall survival.

Conclusions

WASF2 is overexpressed and hypomethylated in HCC and correlates with patient prognosis. WASF2 inactivation exerts anti-tumorigenic effects on HCC cells in vitro and in vivo, suggesting that WASF2 could be a potential therapeutic target for HCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-022-02365-7.

PVT1 inhibits miR-515-5p function and modulate HMGB3 to promote the growth of prostate cancer cells

AIM

This study is performed to analyze the role of long non-coding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) in prostate cancer (PCa).

METHODS AND MATERIALS

PVT1, miR-515-5p, and high mobility group B3 (HMGB3) mRNA expressions were examined using quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC). After gain-of-function and loss-of-function models were established, the changes in cell proliferation, migration, and invasion were evaluated using cell counting kit-8 (CCK-8) assay, 5-Ethynyl-2'-deoxyuridine (EdU) assay, and Transwell experiments. Validation of the targeting relationships between PVT1 and miR-515-5p, and between miR-515-5p and HMGB3 was conducted using bioinformatics prediction, dual-luciferase reporter assay, and RNA immunoprecipitation (RIP) experiment. Moreover, the effects of PVT1 and miR-515-5p on HMGB3 protein expression were examined using Western blot.

RESULTS

PVT1 expression and HMGB3 expression were up-regulated in PCa tissues and cell lines while miR-515-5p expression was down-regulated. PVT1 knockdown restrained the proliferation, migration, and invasion of LNCaP and DU145 cells in vitro, and the transfection with miR-515-5p inhibitors reversed these effects. Mechanistically, PVT1 could repress the function of miR-515; HMGB3 was proved to be a target gene of miR-515-5p, and its expression could be indirectly positively modulated by PVT1.

CONCLUSION

PVT1 accelerates PCa progression by repress miR-515-5p's function to upregulate HMGB3 expression. This article is protected by copyright. All rights reserved.

Emerging Trends in Deciphering the Pathogenesis of Human Diseases through Genetic Analysis

Any changes in gene expression or protein functions can cause abnormal anatomical, physiological, biochemical, and behavioral modifications in human beings, which can lead to disease [...].