Genetic Variants in WNT2B and BTRC Predict Melanoma Survival

Contribution of WNT2B Genetic Variants to Ischemic Stroke Occurrence in a Chinese Han Population

ABSTRACT

Wnt signaling pathway-related WNT2B gene was upregulated in ischemic brain damage. We aimed to assess the contribution of WNT2B genetic variant to ischemic stroke (IS) susceptibility in the Chinese Han population. Five polymorphisms including rs3790606, rs351364, rs3790608, rs12037987, and rs10776752 in WNT2B were genotyped using Agena MassARRAY platform in 476 healthy controls and 501 patients with IS. Odds ratio (OR) and 95% confidence interval (CI) adjusted for age and gender were estimated by logistic regression analysis. Analysis of variance was used to evaluate the association between genotypes of WNT2B variants and blood lipid parameters. Rs12037987 (OR = 1.82, 95% CI: 1.18-2.82, P = 0.007) and rs10776752 (OR = 1.74, 95% CI: 1.13-2.68, P = 0.012) were related to the increased IS susceptibility. Interestingly, rs12037987 (OR = 2.01, P = 0.028) and rs10776752 (OR = 2.02, P = 0.028) had the higher IS risk in the subjects younger than or equal to 65 years. Rs12037987 (OR = 2.70, P = 0.013), rs10776752 (OR = 2.71, P = 0.012), and rs3790606 (OR = 1.89, P = 0.036) manifested an increasing-risk association with IS occurrence in women. Moreover, rs3790606 genotype was related to serum levels of triglyceride (P = 0.008) and total cholesterol (P = 0.001). Our study reported that rs12037987 and rs10776752 were associated with the increased risk for IS in the Chinese Han population. Our findings may be useful for insight into the contribution of WNT2B variants to the complex pathogenesis of IS.

Single cell transcriptomic analysis of human pluripotent stem cell chondrogenesis

The therapeutic application of human induced pluripotent stem cells (hiPSCs) for cartilage regeneration is largely hindered by the low yield of chondrocytes accompanied by unpredictable and heterogeneous off-target differentiation of cells during chondrogenesis. Here, we combine bulk RNA sequencing, single cell RNA sequencing, and bioinformatic analyses, including weighted gene co-expression analysis (WGCNA), to investigate the gene regulatory networks regulating hiPSC differentiation under chondrogenic conditions. We identify specific WNTs and MITF as hub genes governing the generation of off-target differentiation into neural cells and melanocytes during hiPSC chondrogenesis. With heterocellular signaling models, we further show that WNT signaling produced by off-target cells is responsible for inducing chondrocyte hypertrophy. By targeting WNTs and MITF, we eliminate these cell lineages, significantly enhancing the yield and homogeneity of hiPSC-derived chondrocytes. Collectively, our findings identify the trajectories and molecular mechanisms governing cell fate decision in hiPSC chondrogenesis, as well as dynamic transcriptome profiles orchestrating chondrocyte proliferation and differentiation.

Role of miR-214 in regulation of β-catenin and the malignant phenotype of melanoma

Wnt/β-catenin signaling plays an important role in melanocyte biology, especially in the early stages of melanocyte transformation and melanomagenesis. β-catenin, encoded by the gene CTNNB1, is an intracellular signal transducer of Wnt signaling and activates transcription of genes important for cell proliferation and survival. Wnt/β-catenin signaling is frequently activated in melanoma through oncogenic mutations of β-catenin and elevated β-catenin levels are positively correlated with melanoma aggressiveness. Molecular mechanisms that regulate β-catenin expression in melanoma are not fully understood. MicroRNA-214 is known to function as a tumor suppressor by targeting β-catenin in several types of cancer cells. Here, we investigated the regulation of β-catenin by miR-214 and its role in melanoma. We show that β-catenin mRNA levels are negatively correlated with miR-214 in melanoma. However, overexpression of miR-214 paradoxically increased β-catenin protein levels and promoted malignant properties of melanoma cells including resistance to mitogen-activated protein kinase inhibitors (MAPKi). RNA-seq analysis revealed that melanoma cells predominantly express a β-catenin mRNA isoform lacking miR-214 target site. Using matched miRNA and mRNA-seq and bioinformatics analysis, we identified novel miR-214 targets, ankyrin repeat domain 6 (ANKRD6) and C-terminal binding protein 1 (CTBP1), that are involved in negative regulation of Wnt signaling. Overexpression of miR-214 or knockdown of the novel miR-214 targets, ANKRD6 or CTBP1, increased melanoma cell proliferation, migration, and decreased sensitivity to MAPKi. Our data suggest that in melanoma cells β-catenin is not regulated by miR-214 and the functions of miR-214 in melanoma are mediated partly by regulating proteins involved in attenuation of Wnt/β-catenin signaling.

Diagnostic and prognostic value of WNT family gene expression in hepatitis B virus‑related hepatocellular carcinoma

The aim of the present study was to investigate the diagnostic and prognostic value of Wingless-type MMTV integration site (WNT) gene family expression in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). The clinical data of the patients and gene expression levels were downloaded from Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases. Receiver operating characteristic curve analysis was used to investigate the diagnostic value of WNT genes. Cox proportional hazard regression analysis and Kaplan-Meier survival analysis were performed to evaluate the association of WNT gene expression level with overall survival (OS) and recurrence-free survival (RFS). A nomogram was constructed for the prediction of prognosis. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated. Diagnostic receiver operating characteristic curve analysis suggested that WNT2 had a high diagnostic value, with an area under the curve (AUC) of >0.800 (P<0.0001, AUC=0.810, 95% CI: 0.767–0.852). Survival analysis indicated that the expression level of WNT1 was significantly associated with OS and RFS (adjusted P=0.033, adjusted HR=0.607, 95% CI: 0.384–0.960; and adjusted P=0.007, adjusted HR=0.592, 95% CI: 0.404–0.868, respectively). In the TCGA validation cohort, we also observed that WNT2 was significantly differentially expressed between HCC tissues and adjacent non-tumor tissues, and WNT1 was associated with both the OS and RFS of HCC. Therefore, through the GSE14520 HBV-related HCC cohort we concluded that WNT2 may serve as a diagnostic biomarker and WNT1 may serve as a prognostic biomarker. These results may also be extended to TCGA HCC verification cohort.