Nigella sativa L. seeds have been traditionally utilized in Chinese folk medicine for centuries to treat vitiligo. This study revealed that the ethanolic extract of Nigella sativa L. (HZC) enhances melanogenesis and mitigates oxidative stress-induced cellular senescence and dysfunction in melanocytes. In accordance with established protocols, the ethanol fraction from Nigella sativa L. seeds was extracted, concentrated, and lyophilized to evaluate its herbal effects via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, tyrosinase activity evaluation, measurement of cellular melanin contents, scratch assays, senescence-associated β-galactosidase (SA-β-gal) staining, enzyme-linked immunosorbent assay (ELISA), and Western blot analysis for expression profiling of experimentally relevant proteins. The results indicated that HZC significantly enhanced tyrosinase activity and melanin content while notably increasing the protein expression levels of Tyr, Mitf, and gp100 in B16F10 cells. Furthermore, HZC effectively mitigated oxidative stress-induced cellular senescence, improved melanocyte condition, and rectified various functional impairments associated with melanocyte dysfunction. These findings suggest that HZC increases melanin synthesis in melanocytes through the activation of the MAPK, PKA, and Wnt signaling pathways. In addition, HZC attenuates oxidative damage induced by H₂O₂ therapy by activating the nuclear factor E2-related factor 2-antioxidant response element (Nrf2-ARE) pathway and enhancing the activity of downstream antioxidant enzymes, thus preventing premature senescence and dysfunction in melanocytes.
Oxidative Stress/drug effects* ; Melanocytes/cytology* ; Cellular Senescence/drug effects* ; Nigella sativa/chemistry* ; Plant Extracts/pharmacology* ; Seeds/chemistry* ; Mice ; Animals ; Melanins/metabolism* ; Monophenol Monooxygenase/metabolism* ; Humans

Objective:To investigate the clinical significance of monitoring SIL::TAL1 fusion transcripts in the evaluation of treatment response and prognosis of children with T-acute lymphoblastic leukemia (T-ALL).Methods:A retrospective cohort study was conducted to analyze the clinical data of 46 newly diagnosed pediatric T-ALL with SIL::TAL1 fusion transcripts treated at Beijing Children′s Hospital Capital Medical University from November 2004 to December 2022. The SIL::TAL1 fusion transcripts were quantitatively detected at the initial diagnosis (TP0) and early stage of induction therapy (TP1), at the end of induction remission therapy (TP2), before consolidation therapy (TP3) and subsequent treatment. Patients were divided into negative and positive groups on SIL::TAL1 fusion transcripts level, differences of clinical features and survival among groups at TP0 to TP3 were analyzed. The χ2 test or Fisher exact test or Mann-Whitney U test was used to compare the clinical difference. Survival analysis was estimated by Kaplan-Meier method with Log-Rank testing. Multivariate analysis was conducted by Cox proportional hazards models. Results:Among the 46 children with SIL::TAL1 fusion transcripts, 36 were males and 10 were females, with the onset age of 6.8 (3.4, 9.5) years. The negative rates of SIL::TAL1 fusion transcripts for TP1,TP2, TP3, before delayed intensification Ⅰ treatment (TP4), before maintenance therapy (TP5) were 36% (13/36), 78% (32/41), 76% (32/42), 15/16, and 12/12, respectively. No significant difference was found on clinical features and prednisone response between groups at TP0-TP3 (all P>0.05). The 5-year events free survival (EFS) rate of patients classified as negative (32 cases) and positive (9 cases) groups at TP2 was (78±8)% and (33±16)%, respectively ( χ2=9.86, P=0.002), the 5-year overall survival (OS) rate was (81±7)% and (44±17)%, respectively ( χ2=6.40, P=0.011). The 5-year EFS rate of patients classified as negative (32 cases) and positive (10 cases) groups at TP3 was (78±8)% and (30±15)%, respectively ( χ2=13.04, P<0.001) and the 5-year OS rate was (84±6)% and (30±15)%, respectively ( χ2=15.95, P<0.001). Cox multivariate regression showed that positive of SIL::TAL1 transcript at TP3 was adverse independent prognostic factors for EFS and OS (EFS: HR=6.70, 95% CI 2.01-22.35, P=0.002; OS: HR=10.73, 95% CI 2.50-46.09, P=0.001). Conclusions:Monitoring SIL::TAL1 fusion transcripts can reflect the clinical treatment response. The level of SIL::TAL1 fusion transcripts at early period can predict long-term outcomes of these patients.

Pediatric T-cell acute lymphoblastic leukemia (T-ALL) has been attracted much attention due to its high aggressiveness and complexity of treatment. Recently, with the development of technology and clinical research, the curative effect of T-ALL in children has been significantly improved. However, the presence of minimal residual disease (MRD) is still a key factor affecting the outcomes of children with T-ALL. With the continuous development of detection methods, the clinical applications of real-time quantitative PCR, multi-parameter flow cytometry, and high-throughput sequencing technology, MRD can be detected accurately to achieve personalized and precise treatment for each patient. The purpose of this article is to review the current detection methods of MRD in T-ALL, the clinical significance of MRD monitoring and evaluation in multi-agent combined chemotherapy and hematopoietic stem cell transplantation, and applying MRD to measure the responsiveness and effectiveness of new therapies in recent T-ALLs. Research directions and potential treatment strategies in the near future were also proposed.

Pediatric T-cell acute lymphoblastic leukemia (T-ALL) has been attracted much attention due to its high aggressiveness and complexity of treatment. Recently, with the development of technology and clinical research, the curative effect of T-ALL in children has been significantly improved. However, the presence of minimal residual disease (MRD) is still a key factor affecting the outcomes of children with T-ALL. With the continuous development of detection methods, the clinical applications of real-time quantitative PCR, multi-parameter flow cytometry, and high-throughput sequencing technology, MRD can be detected accurately to achieve personalized and precise treatment for each patient. The purpose of this article is to review the current detection methods of MRD in T-ALL, the clinical significance of MRD monitoring and evaluation in multi-agent combined chemotherapy and hematopoietic stem cell transplantation, and applying MRD to measure the responsiveness and effectiveness of new therapies in recent T-ALLs. Research directions and potential treatment strategies in the near future were also proposed.

Objective:To investigate the clinical significance of monitoring SIL::TAL1 fusion transcripts in the evaluation of treatment response and prognosis of children with T-acute lymphoblastic leukemia (T-ALL).Methods:A retrospective cohort study was conducted to analyze the clinical data of 46 newly diagnosed pediatric T-ALL with SIL::TAL1 fusion transcripts treated at Beijing Children′s Hospital Capital Medical University from November 2004 to December 2022. The SIL::TAL1 fusion transcripts were quantitatively detected at the initial diagnosis (TP0) and early stage of induction therapy (TP1), at the end of induction remission therapy (TP2), before consolidation therapy (TP3) and subsequent treatment. Patients were divided into negative and positive groups on SIL::TAL1 fusion transcripts level, differences of clinical features and survival among groups at TP0 to TP3 were analyzed. The χ2 test or Fisher exact test or Mann-Whitney U test was used to compare the clinical difference. Survival analysis was estimated by Kaplan-Meier method with Log-Rank testing. Multivariate analysis was conducted by Cox proportional hazards models. Results:Among the 46 children with SIL::TAL1 fusion transcripts, 36 were males and 10 were females, with the onset age of 6.8 (3.4, 9.5) years. The negative rates of SIL::TAL1 fusion transcripts for TP1,TP2, TP3, before delayed intensification Ⅰ treatment (TP4), before maintenance therapy (TP5) were 36% (13/36), 78% (32/41), 76% (32/42), 15/16, and 12/12, respectively. No significant difference was found on clinical features and prednisone response between groups at TP0-TP3 (all P>0.05). The 5-year events free survival (EFS) rate of patients classified as negative (32 cases) and positive (9 cases) groups at TP2 was (78±8)% and (33±16)%, respectively ( χ2=9.86, P=0.002), the 5-year overall survival (OS) rate was (81±7)% and (44±17)%, respectively ( χ2=6.40, P=0.011). The 5-year EFS rate of patients classified as negative (32 cases) and positive (10 cases) groups at TP3 was (78±8)% and (30±15)%, respectively ( χ2=13.04, P<0.001) and the 5-year OS rate was (84±6)% and (30±15)%, respectively ( χ2=15.95, P<0.001). Cox multivariate regression showed that positive of SIL::TAL1 transcript at TP3 was adverse independent prognostic factors for EFS and OS (EFS: HR=6.70, 95% CI 2.01-22.35, P=0.002; OS: HR=10.73, 95% CI 2.50-46.09, P=0.001). Conclusions:Monitoring SIL::TAL1 fusion transcripts can reflect the clinical treatment response. The level of SIL::TAL1 fusion transcripts at early period can predict long-term outcomes of these patients.

Uch37 is a de-ubiquitinating enzyme that is activated by Rpn13 and involved in the proteasomal degradation of proteins. The full-length Uch37 was shown to exhibit low iso-peptidase activity and is thought to be auto-inhibited. Structural comparisons revealed that within a homo-dimer of Uch37, each of the catalytic domains was blocking the other's ubiquitin (Ub)-binding site. This blockage likely prevented Ub from entering the active site of Uch37 and might form the basis of auto-inhibition. To understand the mode of auto-inhibition clearly and shed light on the activation mechanism of Uch37 by Rpn13, we investigated the Uch37-Rpn13 complex using a combination of mutagenesis, biochemical, NMR, and small-angle X-ray scattering (SAXS) techniques. Our results also proved that Uch37 oligomerized in solution and had very low activity against the fluorogenic substrate ubiquitin-7-amino-4-methylcoumarin (Ub-AMC) of de-ubiquitinating enzymes. Uch37Δ(Hb,Hc,KEKE), a truncation removal of the C-terminal extension region (residues 256-329) converted oligomeric Uch37 into a monomeric form that exhibited iso-peptidase activity comparable to that of a truncation-containing the Uch37 catalytic domain only. We also demonstrated that Rpn13C (Rpn13 residues 270-407) could disrupt the oligomerization of Uch37 by sequestering Uch37 and forming a Uch37-Rpn13 complex. Uch37 was activated in such a complex, exhibiting 12-fold-higher activity than Uch37 alone. Time-resolved SAXS (TR-SAXS) and FRET experiments supported the proposed mode of auto-inhibition and the activation mechanism of Uch37 by Rpn13. Rpn13 activated Uch37 by forming a 1:1 stoichiometric complex in which the active site of Uch37 was accessible to Ub.
Binding Sites ; Catalytic Domain ; Chromatography, Gel ; Crystallography, X-Ray ; Humans ; Membrane Glycoproteins ; chemistry ; genetics ; metabolism ; Nuclear Magnetic Resonance, Biomolecular ; Protein Binding ; Protein Conformation ; Protein Multimerization ; Scattering, Small Angle ; Ubiquitin Thiolesterase ; chemistry ; genetics ; metabolism ; Ultracentrifugation

TRAF4 is a unique member of TRAF family, which is essential for innate immune response, nervous system and other systems. In addition to be an adaptor protein, TRAF4 was identified as a regulator protein in recent studies. We have determined the crystal structure of TRAF domain of TRAF4 (residues 292-466) at 2.60 Å resolution by X-ray crystallography method. The trimericly assembled TRAF4 resembles a mushroom shape, containing a super helical "stalk" which is made of three right-handed intertwined α helixes and a C-terminal "cap", which is divided at residue L302 as a boundary. Similar to other TRAFs, both intermolecular hydrophobic interaction in super helical "stalk" and hydrogen bonds in "cap" regions contribute directly to the formation of TRAF4 trimer. However, differing from other TRAFs, there is an additional flexible loop (residues 421-426), which contains a previously identified phosphorylated site S426 exposing on the surface. This S426 was reported to be phosphorylated by IKKα which is the pre-requisite for TRAF4-NOD2 complex formation and thus to inhibit NOD2-induced NF-κB activation. Therefore, the crystal structure of TRAF4-TRAF is valuable for understanding its molecular basis for its special function and provides structural information for further studies.
Amino Acid Sequence ; Binding Sites ; Crystallography, X-Ray ; Humans ; Hydrophobic and Hydrophilic Interactions ; Models, Molecular ; Phosphorylation ; Protein Conformation, alpha-Helical ; Protein Domains ; Protein Structure, Quaternary ; Recombinant Proteins ; chemistry ; Sequence Homology, Amino Acid ; TNF Receptor-Associated Factor 4 ; chemistry