Biomedical subjects

Haiyan Zheng

Publications and source records attributed to Haiyan Zheng.

3 recordsLinked to original sources

PubMed2026

Long-term outcomes of top-down therapy versus a conventional step-up strategy in adults newly diagnosed with Crohn's disease: 5-year follow-up of the PROFILE trial.

BACKGROUND: The PROFILE trial previously reported better 48-week outcomes for patients with Crohn's disease who received top-down anti-TNF treatment from diagnosis, compared with a conventional step-up strategy. Through subsequent follow-up of PROFILE participants, we aimed to assess whether the benefit of top-down treatment from diagnosis results in modification of the long-term disease course. METHODS: PROFILE was a multicentre, open-label, randomised controlled trial completed in 40 hospitals in the UK, which included patients aged 16-80 years with newly diagnosed Crohn's disease. Eligible patients were randomly assigned via a secure online platform to a top-down (infliximab plus immunomodulator) or a step-up protocolised treatment strategy for 48 weeks, after which participants reverted to local standards of care. Objective outcome data were extracted for up to 5 years after the week 48 visit, including need for Crohn's-related abdominal surgery as the primary outcome. Data were analysed based on the original PROFILE randomisation and intention-to-treat population. Participants without long-term follow-up data were censored at the week 48 visit. Time-to-event analyses were performed using the Kaplan-Meier method and Cox proportional hazards model. The trial was registered with the ISRCTN registry, number 11808228 and is complete. FINDINGS: Between Dec 29, 2017, and Jan 5, 2022, 483 patients were assessed for inclusion. 389 patients were enrolled and randomly assigned (three patients were excluded due to ineligibility), 193 to top-down treatment and 193 to step-up treatment. Of the 386 participants in the PROFILE primary trial, 358 (93%) had post-week 48 records available for review (182 [51%] top-down and 176 [49%] step-up). Median follow-up was approximately 5 years from randomisation (1809 days [IQR 1300-2101]), by which point 172 (89%) of 193 patients in the step-up group and 191 (99%) of 193 patients in the top-down group had received biological or immunomodulator therapy. Relating to the primary outcome, during follow-up there were 28 Crohn's disease-related abdominal surgeries in 26 patients treated with a step-up approach versus six surgeries in six patients treated with a top-down approach. Time to surgery was shorter in the step-up group than the top-down group (adjusted hazard ratio [aHR] 5·23 [95% CI 1·99-13·76]; p=0·0008). For the secondary outcomes, incidence of Crohn's disease-related hospital admissions was higher in patients originally managed with step-up treatment versus top-down treatment (41 [21%] of 193 patients vs 22 [11%] of 193 patients); and time to first hospital admission was shorter with step-up treatment than with top-down treatment (aHR 2·01 [95% CI 1·18-3·41], p=0·017). Progression to B2 or B3 complications was also more frequent in those originally managed with step-up treatment compared with top-down treatment (32 [17%] of 192 patients vs 13 [7%] of 193 patients); with time to disease progression being shorter in the step-up group than in the top-down group (aHR 2·46 [95% CI 1·25-4·86]; p=0·010). There was no difference in safety outcomes between groups for either serious infections (12 [6%] of 193 step-up patients and 14 [7%] of 193 top-down patients) or malignancies (five patients [3%] and three patients [2%] respectively). INTERPRETATION: Early top-down anti-TNF treatment from diagnosis was associated with improved long-term outcomes at 5 years compared with step-up treatment and is suggestive of a disease-modifying effect in Crohn's disease. FUNDING: Wellcome and Celltrion.

Journal Article↗

PubMed2025

O-GlcNAcylation of nuclear proteins in the mouse liver exhibit daily oscillations that are influenced by meal timing.

The liver circadian clock and hepatic transcriptome are highly responsive to metabolic signals generated from feeding-fasting rhythm. Previous studies have identified a number of nutrient-sensitive signaling pathways that could interpret metabolic input to regulate rhythmic hepatic biology. Here, we investigated the role of O-GlcNAcylation, a nutrient-sensitive post-translational modification (PTM) in mediating metabolic regulation of rhythmic biology in the liver. We observe daily oscillation of global nuclear protein O-GlcNAcylation in the liver of mice subjected to night-restricted feeding (NRF) using label-free global O-GlcNAc proteomics. Additional site-specific O-GlcNAc analysis by tandem mass tag mass spectrometry further supports temporal differences in O-GlcNAcylation by revealing day-night differences. Proteins involved in gene expression are enriched among rhythmically O-GlcNAcylated proteins, suggesting rhythmic O-GlcNAcylation may directly regulate the hepatic transcriptome. We show that rhythmic O-GlcNAcylation can also indirectly modulate nuclear proteins by interacting with phosphorylation. Several proteins harboring O-GlcNAcylation-phosphorylation interplay motif exhibit rhythmic O-GlcNAcylation and phosphorylation. Specifically, we show that O-GlcNAcylation occurs at a phospho-degron of a key circadian transcriptional activator, circadian locomotor output cycles kaput (CLOCK), thus regulating its stability and transcriptional output. Finally, we report that day-restricted feeding (DRF) in the nocturnal mouse significantly alters O-GlcNAcylation pattern. Whereas global O-GlcNAcylation analysis indicates dampening of global O-GlcNAcylation rhythm in mice fed under DRF, site-specific analysis reveals differential responses of O-GlcNAc sites when timing of food intake is altered. Notably, a substantial number of O-GlcNAcylation sites exhibit inverted day-night profiles when mice are subjected to DRF. This suggests the dysregulation of daily nuclear protein O-GlcNAcylation rhythm may contribute to the disruption in liver transcriptome previously observed in DRF condition. In summary, our results provide new mechanistic insights into metabolic regulation of hepatic transcriptional regulators via interplay between O-GlcNAcylation and phosphorylation and shed light on the deleterious effects of improper mealtimes.

Animals↗

PubMed2024

RNF4 sustains Myc-driven tumorigenesis by facilitating DNA replication.

The mammalian SUMO-targeted E3 ubiquitin ligase Rnf4 has been reported to act as a regulator of DNA repair, but the importance of RNF4 as a tumor suppressor has not been tested. Using a conditional-knockout mouse model, we deleted Rnf4 in the B cell lineage to test the importance of RNF4 for growth of somatic cells. Although Rnf4-conditional-knockout B cells exhibited substantial genomic instability, Rnf4 deletion caused no increase in tumor susceptibility. In contrast, Rnf4 deletion extended the healthy lifespan of mice expressing an oncogenic c-myc transgene. Rnf4 activity is essential for normal DNA replication, and in its absence, there was a failure in ATR-CHK1 signaling of replication stress. Factors that normally mediate replication fork stability, including members of the Fanconi anemia gene family and the helicases PIF1 and RECQL5, showed reduced accumulation at replication forks in the absence of RNF4. RNF4 deficiency also resulted in an accumulation of hyper-SUMOylated proteins in chromatin, including members of the SMC5/6 complex, which contributes to replication failure by a mechanism dependent on RAD51. These findings indicate that RNF4, which shows increased expression in multiple human tumor types, is a potential target for anticancer therapy, especially in tumors expressing c-myc.

Animals↗