Phosphorylation of UHRF2 affects malignant phenotypes of HCC and HBV replication by blocking DHX9 ubiquitylation

New daphnane diterpenoidal 1,3,4-oxdiazole derivatives as potential anti-hepatoma agents: Synthesis, biological evaluation and molecular modeling studies

Hepatocellular carcinoma (HCC) is a major challenge for human healthy. Daphnane-type diterpenes have attracted increasingly attention due to remarkable pharmaceutical potential including anti-HCC activity. To further develop this class of compounds as inhibitors of HCC, the daphnane diterpenoids 12-O-debenzoyl-Yuanhuacine (YHC) and 12-hydroxydaphnetoxin (YHE) were prepared by a standard chemical transformation from dried flower buds of the Daphne genkwa plant. Subsequently, 22 daphnane diterpenoidal 1,3,4-oxdiazole derivatives were rationally designed and synthesized based on YHC and YHE. The assessment of the target compound's anti-hepatocellular carcinoma activity revealed that YHC1 exhibited comparable activity to sorafenib in the Hep3B cell line, while demonstrating higher selectivity. The mechanistic investigation demonstrates that compound YHC1 induces cell cycle arrest at the G0/G1 phase, cellular senescence, apoptosis, and elevates cellular reactive oxygen species levels. Moreover, molecular docking and CETSA results confirm the interaction between YHC1 and YAP1 as well as TEAD1. Co-IP experiments further validated that YHC1 can effectively inhibit the binding of YAP1 and TEAD1. In conclusion, YHC1 selectively targets YAP1 and TEAD1, exhibiting its anti-hepatocellular carcinoma effects through the inhibition of their interaction.

UHRF2 accumulates in early G1-phase after serum stimulation or mitotic exit to extend G1 and total cell cycle length

Ubiquitin like with PHD and ring finger domains 2 (UHRF2) regulates the cell cycle and epigenetics as a multi-domain protein sharing homology with UHRF1. UHRF1 functions with DNMT1 to coordinate daughter strand methylation during DNA replication, but UHRF2 can't perform this function, and its roles during cell cycle progression are not well defined. UHRF2 role as an oncogene vs. tumor suppressor differs in distinct cell types. UHRF2 interacts with E2F1 to control Cyclin E1 (CCNE1) transcription. UHRF2 also functions in a reciprocal loop with Cyclin E/CDK2 during G1, first as a direct target of CDK2 phosphorylation, but also as an E3-ligase with direct activity toward both Cyclin E and Cyclin D. In this study, we demonstrate that UHRF2 is expressed in early G1 following either serum stimulation out of quiescence or in cells transiting directly out of M-phase, where UHRF2 protein is lost. Further, UHRF2 depletion in G2/M is reversed with a CDK1 specific inhibitor. UHRF2 controls expression levels of cyclins and CDK inhibitors and controls its own transcription in a negative-feedback loop. Deletion of UHRF2 using CRISPR/Cas9 caused a delay in passage through each cell cycle phase. UHRF2 loss culminated in elevated levels of cyclins but also the CDK inhibitor p27KIP1, which regulates G1 passage, to reduce retinoblastoma phosphorylation and increase the amount of time required to reach G1/S passage. Our data indicate that UHRF2 is a central regulator of cell-cycle pacing through its complex regulation of cell cycle gene expression and protein stability.

Occult hepatitis B in blood donation centers

Occult hepatitis B (OHB) is characterized by the presence of hepatitis B virus (HBV) DNA in the blood of individuals who test negative for the hepatitis B surface antigen (HBsAg). OHB in blood donors can lead to HBV transmission through transfusions, yet the prevalence of OHB in Basrah, Iraq, is unknown. This study aimed to determine the prevalence of OHB in blood donation centers in Basrah and investigate the immune response to HBV in OHB-positive donors. We recruited 450 blood donors and categorized them into four groups based on HBV markers: the HBsAg-negative/HBsAb-negative/HBcAb-positive group, the recovery group (HBsAg-negative/HBsAb-positive/HBcAb-positive), the patient group (HBsAg-positive/HBsAb-negative/HBcAb-positive), and the apparently healthy group (negative for all HBV markers). We measured levels of IgG, IgM, complement components (C3 and C4), ALT, AST, and serum ALP in OHB-positive donors. Of the 450 donors, 97 (21.6%) were OHB-positive. IgG levels were significantly higher than IgM levels in OHB-positive donors. Healthy and HBsAg-negative/HBsAb-positive donors had significantly lower C3 levels than patients. IgG levels were significantly higher than IgM in both the patient and recovery groups. C3 levels were higher than C4 levels in all groups. The serum ALP level was significantly higher in the patient group. OHB prevalence in Basrah blood donors is high, indicating the potential for HBV transmission. OHB-positive donors showed an immune response to HBV. Our study provides insights into OHB prevalence and immune response in Basrah, with implications for diagnostic and therapeutic approaches in blood donation centers.