Biology subjects

Wong, C. C.

Publications and source records attributed to Wong, C. C..

6 recordsLinked to original sources

bioRxiv2026

NRF2 co-opts the SWI/SNF complex to drive liver cell plasticity

Nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor that plays a role in the regulation of redox homeostasis and cellular metabolism. Activating mutations in the NRF2 pathway have been identified in approximately 15% of liver cancer patients. However, the mechanisms by which NRF2 promotes liver tumorigenesis are poorly understood. Employing a transgenic zebrafish model with hepatocyte-specific, inducible expression of a clinically relevant constitutively active NRF2 mutant (NRF2T80K), we show that constitutive activation of NRF2 drives hepatocyte to cholangiocyte transdifferentiation. Importantly, we demonstrate that NRF2 affects liver cell plasticity in a cell-autonomous, evolutionarily conserved, and reversible manner. Utilizing an epigenetic-focused chemical screen, the BRG1/BRM inhibitor FHD-286 was identified as a potent suppressor of NRF2-driven transdifferentiation. Overall, our study reveals a novel role for NRF2 in the regulation of liver cell plasticity during tumour initiation and identifies a therapeutic approach to overcome the oncogenic activity of NRF2.

cancer biology↗

bioRxiv2025

Metabolic modulation of intratumoral cholesterol with gut microbiota for the treatment of colorectal cancer

Excess cholesterol is positively correlated with colorectal cancer (CRC). Current therapeutic strategies for modulating cholesterol levels in CRC are limited and often come with complications. Here, we demonstrated that microbiome shunting of intestinal cholesterol to anticancer metabolites is a safe and applicable therapeutic approach for CRC. By screening major microbial metabolic products of cholesterol, we found that 4-cholesten-3-one (4-C-3) was selectively depleted in fecal samples and tumor tissues of patients with CRC. 4-C-3 exhibits strong antitumor effects on human CRC cell lines, patient-derived organoids, and patient-derived xenograft (PDX) models. Mechanistically, 4-C-3 suppresses CRC tumorigenesis by dually targeting the epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma viral oncogene homologue (KRAS). 4-C-3 directly binds to EGFR, blocking its signal transduction by inhibiting the binding of EGFR ligands. Additionally, 4-C-3 inhibits oncogenic KRAS variants, such as KRASG12D, by suppressing nucleotide exchange activity and effector engagement. By targeting both EGFR and KRAS, 4-C-3 reduces primary resistance to anti-EGFR therapies caused by KRAS mutations in CRC. As a proof-of-concept study, we showed that delivery of 4-C-3 by Oscillibacter ruminantium, a 4-C-3- producing commensal bacterium that is reduced in CRC patients, or a nonpathogenic Escherichia coli strain engineered to specifically convert intestinal cholesterol into 4-C-3, removed intratumoral cholesterol and led to rapid tumor regression in multiple models of CRC. These results suggest that microbial therapies for restoring intestinal cholesterol homeostasis represent a new therapeutic avenue for CRC.

cancer biology↗

bioRxiv2022

Assessing base-resolution DNA mechanics on the genome scale

Intrinsic DNA properties such as bending play a crucial role in diverse biological systems. A recent advantage in the high-throughput method called loop-seq makes it possible to determine bendability of hundred thousand 50-bp DNA duplexes in one experiment. However, its still infeasible to assess whole sequence bendability in large genomes such as human, which needs thousands of loop-seq experiments. Here we introduce BendNet - a neural network to accurately predict the intrinsic DNA bending at base-resolution by only given DNA sequences. BendNet can increase the resolution of experimental results, and can predict DNA bendability for any new given sequences in high accuracy. We applied BendNet to the human genome and observed high-stiffness regions located at both transcriptional start sites and transcriptional end sites. Such stiffness patterns are different for coding and non-coding genes, which matches distinct nucleosome occupancy patterns. As expected, most transcription factors (TFs) bind in DNA of low bendability. In contrast, we observed an unusually high bendability within binding elements of specific TFs such as EBF1 and regulators of genome folding such as CTCF. These factors either co-bind or compete with nucleosomes to carry out their functions. More interestingly, CTCF binding regions exhibit the highest bendability than other DNA elements, implying their potential role in trapping and holding the CTCF in the exact locations to make sure CTCF as stable anchor in loop extrusion process. Our work provides a tool to assess DNA bendability for large-scale DNA sequences and expands our understanding on DNA mechanics in chromatin regulation and genome folding.

genomics↗

bioRxiv2021

eIF6 rebinding dynamically couples ribosome maturation and translation

Protein synthesis is a cyclical process consisting of translation initiation, elongation, termination and ribosome recycling. The release factors SBDS and EFL1 (both mutated in the leukaemia predisposition disorder Shwachman-Diamond syndrome) license entry of nascent 60S ribosomal subunits into active translation by evicting the anti-association factor eIF6 from the 60S intersubunit face. Here, we show that in mammalian cells, eIF6 holds all free cytoplasmic 60S subunits in a translationally inactive state and that SBDS and EFL1 are the minimal components required to recycle these 60S subunits back into additional rounds of translation by evicting eIF6. Increasing the dose of eIF6 in mice in vivo impairs terminal erythropoiesis by sequestering post-termination 60S subunits in the cytoplasm, disrupting subunit joining and attenuating global protein synthesis. Our data reveal that ribosome maturation and recycling are dynamically coupled by a mechanism that is disrupted in an inherited leukaemia predisposition disorder.

cell biology↗

bioRxiv2021

Unconventional tonicity-regulated nuclear trafficking of NFAT5 mediated by KPNB1, XPOT and RUVBL2

NFAT5 is the only known mammalian tonicity-responsive transcription factor functionally implicated in diverse physiological and pathological processes. NFAT5 activity is tightly regulated by extracellular tonicity but the underlying mechanisms remain elusive. We demonstrated that NFAT5 enters the nucleus via the nuclear pore complex. We also found that NFAT5 utilizes a non-canonical nuclear localization signal (NFAT5-NLS) for nuclear imports. siRNA screening revealed that karyopherin {beta}1 (KPNB1) drives nuclear import of NFAT5 via directly interacting with NFAT5-NLS. Proteomics analysis and siRNA screening further revealed that nuclear export of NFAT5 under hypotonicity is mediated by Exportin-T, and that it requires RuvB-Like AAA type ATPase 2 (RUVBL2) as an indispensable chaperone. Our findings have identified KPNB1 and RUVBL2 as key molecules responsible for the unconventional tonicity-regulated nucleocytoplasmic shuttling of NFAT5. These findings offer an opportunity for developing novel NFAT5 targeting strategies that are potentially useful for the treatment of diseases associated with NFAT5 dysregulation.

cell biology↗

bioRxiv2020

Enrichment-Free Identification of Native Definitive (EnFIND) O-glycoproteome of antibodies in autoimmune diseases

The detection of O-glycosylation at the proteome level has long been a challenging task and a roadblock for O-linked protein glycosylation research. We report an Enrichment-Free Identification of Native Definitive (EnFIND) O-glycoproteome using Trapped Ion Mobility Spectrometry coupled to TOF Mass Spectrometry (TIMS-TOF MS) for direct analysis of protein O-glycosylation in native samples with minimum sample requirement. This approach enabled separation of O-glycopeptide isomers, resolution of O-glycosites and O-glycoform, reduction of sample complexity, and increased sensitivity, thus greatly enhancing analysis of the O-glycoproteome of cell lysates, human serum and exosomes. In addition, we found that antibodies in human serum are highly O-glycosylated on variable, especially hypervariable regions and constant regions, which significantly increases antibody diversity. This method was used to successfully identify characteristic O-glycosylation features of autoimmune diseases.

systems biology↗