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Wang, W.-T.

Publications and source records attributed to Wang, W.-T..

3 recordsLinked to original sources

Store-operated Ca2+ entry is involved in endothelium-to-mesenchymal transition in lung vascular endothelial cells

Endothelial-to-mesenchymal transition (EndMT) is a biological process that converts endothelial cells to mesenchymal cells with increased proliferative and migrative abilities. EndMT has been implicated in the development of pulmonary vascular remodeling in pulmonary arterial hypertension (PAH), a fatal and progressive lung vascular disease. Transforming growth factor {beta}1 (TGF-{beta}1), an inflammatory cytokine, is known to induce EndMT in many types of endothelial cells including lung vascular endothelial cells (LVEC). An increase in cytosolic free Ca2+ concentration ([Ca2+]cyt) is a major stimulus for cellular proliferation and phenotypic transition, but it is unknown whether Ca2+ signaling is involved in EndMT. In this study we tested the hypothesis that TGF-{beta}1-induced EndMT in human LVEC is Ca2+-dependent. Treatment of LVEC with TGF-{beta}1 for 5-7 days resulted in increase in SNAI1/2 expression, induction of EndMT, upregulation of STIM/Orai1 and enhancement of store-operated Ca2+ entry (SOCE). Removal (or chelation) of extracellular or intracellular Ca2+ with EGTA or BAPTA-AM respectively abolished EndMT in response to TGF-{beta}1. Moreover, EGTA diminished TGF-{beta}1-induced increase in SNAI in a dose-dependent manner. Knockdown of either STIM1 or Orai1 was sufficient to prevent TGF-{beta}-mediated increase in SNAI1/2 and EndMT, but did not rescue the continuous adherent junctions. Blockade of Orai1 channels by AnCoA4 inhibited TGF-{beta}-mediated EndMT and restored PECAM1-positive continuous adherent junctions. In conclusion, intracellular Ca2+ signaling plays a critical role in TGF-{beta}-associated EndMT through enhanced SOCE and STIM1-Orai1 interaction. Thus, targeting Ca2+ signaling pathways regulating EndMT may be a novel therapeutic approach to treat PAH and other forms of pre-capillary pulmonary hypertension. New & NoteworthyEndMT has been reported to contribute to the pathogenesis of PH. In this study we aimed to determine the role of Ca2+ signaling in the development of EndMT in human lung vascular endothelial cells. Our data suggest that TGF-{beta}1 requires store-operated Ca2+ entry through STIM1/Orai channels to induce SNAI-mediated EndMT. For the first time we demonstrated that TGF-{beta}1-induced EndMT is Ca2+-dependent event while inhibition of STIM1/Orai interaction attenuated EndMT in response to TGF-{beta}1.

cell biology↗

Validation of Data Acquisition and Phase Estimation for Quantitative Susceptibility Mapping with a Rotating-Tube Phantom

PurposeQuantitative Susceptibility Mapping (QSM) is an MRI tool with the potential to reveal pathological changes from magnetic susceptibility measurements. Before phase data can be used to recover susceptibility ({Delta}{chi}), the QSM process begins with two steps: data acquisition and phase estimation. We assess the performance of these steps, when applied without user intervention, on several variations of a phantom imaging task. ApproachWe used a rotating-tube phantom with five tubes ranging from {Delta}{chi}=0.05 ppm to {Delta}{chi}=0.336 ppm. MRI data was acquired at nine angles of rotation for four different pulse sequences. The images were processed by 10 phase estimation algorithms including Laplacian, region-growing, branch-cut, temporal unwrapping and maximum-likelihood methods. We analyzed errors between measured and expected phase using the probability mass function and Cumulative Distribution Function. ResultsRepeatable acquisition and estimation methods were identified based on the probability of relative phase errors. For single-echo GRE and segmented EPI sequences, a region-growing method was most reliable with Pr(relative error<0.1)=0.95 and 0.90 respectively. For multi-echo sequences, a Maximum-Likelihood method was most reliable with Pr(relative error<0.1)=0.97. The most repeatable multi-echo methods outperformed the most repeatable single-echo methods. ConclusionsWe found a wide range of repeatability and reproducibility for off-the-shelf MRI acquisition and phase estimation approaches. The error was dominated in many cases by spatially discontinuous phase unwrapping errors. Any post-processing applied on erroneous phase estimates, such as QSMs background field removal and dipole inversion, would suffer from error propagation. Our paradigm identifies methods that yield consistent and accurate phase estimates that would ultimately yield consistent and accurate {Delta}{chi} estimates.

bioengineering↗

Nuclear export of chimeric mRNAs depends on an lncRNA-triggered autoregulatory loop

Aberrant chromosomal translocations leading to tumorigenesis have been ascribed to the heterogeneously oncogenic functions. However, how fusion transcripts exporting remains to be declared. Here, we showed that the nuclear speckle-specific long non coding RNA MALAT1 controls chimeric mRNA export processes and regulates myeloid progenitor cell differentiation in malignant hematopoiesis. We demonstrated that MALAT1 regulates chimeric mRNAs export in an m6A-dependent manner and thus controls hematopoietic cell differentiation. Specifically, reducing MALAT1 or m6A methyltransferases and the reader YTHDC1 result in the universal retention of distinct oncogenic gene mRNAs in nucleus. Mechanically, MALAT1 hijacks both the chimeric mRNAs and fusion proteins in nuclear speckles during chromosomal translocations and mediates the colocalization of oncogenic fusion proteins with METTL14. MALAT1 and fusion protein complexes serve as a functional loading bridge for the interaction of chimeric mRNA and METTL14. This study demonstrated a universal mechanism of chimeric mRNA transport that involves lncRNA-fusion protein-m6A autoregulatory loop for controlling myeloid cell differentiation. Targeting the lncRNA-triggered autoregulatory loop to disrupt chimeric mRNA transport might represent a new common paradigm for treating blood malignancies.

cancer biology↗