Jian Huang’s research while affiliated with The Children’s Hospital of Eastern Ontario and other places

Polycomb repressive complex 2 (PRC2) is responsible for depositing H3K27me3 and plays essential roles in gene silencing during development and cancer. Meanwhile, the nuclear exosome targeting (NEXT) complex facilitates the degradation of numerous noncoding RNAs in the nucleoplasm. Here we find that the functional deficiency of the NEXT complex leads to an overall decrease in H3K27me3 levels. Specifically, ZCCHC8 depletion results in significant upregulation of nascent long noncoding RNAs (lncRNAs) containing G-quadruplex (G4) and U-Rich motifs (G4/U-Rich lncRNAs). The G4 motif binds to EZH2, blocking the chromatin recruitment of PRC2, while the U-Rich motif is specifically recognized by the NEXT complex for RNA exosome-mediated degradation. In tumor tissues with high ZCCHC8 expression in clear cell renal cell carcinoma (ccRCC) and lung adenocarcinoma (LUAD) patients, the NEXT complex excessively degrades nascent G4/U-Rich lncRNAs. Consequently, PRC2 core subunits are released and recruited to neighboring genomic loci, resulting in increased H3K27me3 levels and downregulation of adjacent genes, including tumor suppressors like SEMA5A and ARID1A. Notably, the EZH2 inhibitor Tazemetostat (EPZ-6438) exhibits greater sensitivity in cells with higher ZCCHC8 expression. Altogether, our findings demonstrate a novel mechanism that the NEXT complex regulates H3K27me3 levels by degrading nascent G4/U-Rich lncRNAs in cancer cells.

Recently, imaging investigation of brain development has increasingly captured the attention of researchers and clinicians in an attempt to understand the link between the brain and behavioral changes. Although high-field MR imaging of infants is feasible, the necessary customizations have limited its accessibility, affordability, and reproducibility. Low-field MR, as an emerging solution for scrutinizing developing brain, has exhibited its unique advantages in safety, portability, and cost-effectiveness. The presented low-field infant structural MR data aims to manifest the feasibility of using low-field MR image to exam brain structural changes during early life in infants. The dataset comprises 100 T2 weighed MR images from infants with in-plane resolution of ~0.85 mm and ~6 mm slice thickness. To demonstrate the potential utility, we conducted atlas-based whole brain segmentations and volumetric quantifications to analyze brain development features in first 10 week in postnatal life. This dataset addresses the scarcity of a large, extended-span infant brain dataset that restricts the further tracking of infant brain development trajectories and the development of routine low-field MR imaging pipelines.

Background The standard first‐line treatment for human epidermal growth factor receptor 2 (HER2)‐positive recurrent/metastatic breast cancer currently includes pertuzumab plus trastuzumab and docetaxel. This study aimed to evaluate the effectiveness of KN026, an anti‐HER2 bispecific antibody, plus docetaxel in first‐line treatment of HER2‐positive recurrent/metastatic breast cancer. Methods This open‐label, single‐arm, phase II study enrolled patients with HER2‐positive recurrent/metastatic breast cancer in 19 centers across China from December 30, 2019 to May 27, 2021. Patients were administered KN026 (30 mg/kg) plus docetaxel (75 mg/m²) in 21‐day cycles. Primary endpoints included the objective response rate (ORR) and duration of response (DOR). In addition, overall survival (OS), progression‐free survival (PFS), clinical benefit rate (CBR) and safety profile were examined. Results A total of 57 patients were included. In the efficacy analysis set of 55 patients, the ORR was 76.4% (95% confidence interval [CI], 63.0%‐86.8%), and the CBR was 85.5% (95% CI, 73.3%‐93.5%). The median DOR was not reached (95% CI, 20.7 months‐not reached). In the safety set of 57 patients, the median PFS was 27.7 months (95% CI, 18.0 months‐not reached). The median OS was not reached, with OS rates at 12, 24 and 30 months of 93.0%, 84.1% and 78.5%, respectively. Grade ≥3 treatment‐emergent adverse events (AEs) were detected in 36 (63.2%) patients. No deaths were attributed to KN026 or docetaxel. Conclusion KN026 plus docetaxel showed promising efficacy and a manageable safety profile in first‐line treatment of HER2‐positive recurrent/metastatic breast cancer.

Cytoskeletal remodeling and mitochondrial bioenergetics play important roles in thrombocytopoiesis and platelet function. Recently, α-actinin-1 mutations have been reported in patients with congenital macrothrombocytopenia. However, the role and underlying mechanism of α-actinin-1 in thrombocytopoiesis and platelet function remain elusive. Using MK-specific α-actinin-1 knockout (PF4-Actn1-/-) mice, we demonstrated that PF4-Actn1-/- mice exhibited reduced platelet counts. The decreased platelet number in PF4-Actn1-/- mice was due to defects in thrombocytopoiesis. H&E staining and flow cytometry revealed a decrease in the number of MKs in the bone marrow of PF4-Actn1-/- mice. The absence of α-actinin-1 increased the proportion of 2 N-4 N MKs and decreased the proportion of 8 N-32 N MKs. CFU-MK colony formation, the ratio of proplatelet formation-bearing MKs, and MK migration in response to SDF-1 signaling were inhibited in PF4-Actn1-/- mice. Platelet spreading, clot retraction, aggregation, integrin αIIbβ3 activation, and P-selectin exposure in response to various agonists were decreased in PF4-Actn1-/- platelets. Notably, PF4-Actn1-/- platelets inhibited calcium mobilization, ROS generation, and actin polymerization in response to collagen and thrombin. Furthermore, the PF4-Actn1-/- mice exhibited impaired hemostasis and thrombosis. Mechanistically, proteomic analysis of low-ploidy (2-4 N) and high-ploidy (≥8 N) PF4-Actn1-/- MKs revealed that α-actinin-1 deletion reduced platelet activation and mitochondrial function. PF4-Actn1-/- platelets and Actn1 KO 293T cells exhibited reduced mitochondrial membrane potential, mitoROS generation, mitochondrial calcium mobilization, and mitochondrial bioenergetics. Overall, in this study, we report that mice with α-actinin-1 deficiency in MKs exhibit low platelet count and impaired platelet function, thrombosis, and mitochondrial bioenergetics.

Background Neoadjuvant chemotherapy (NACT) is the standard-of-care treatment for patients with locally advanced breast cancer (LABC), providing crucial benefits in tumor downstaging. Clinical parameters, such as molecular subtypes, influence the therapeutic impact of NACT. Moreover, severe adverse events delay the treatment process and reduce the effectiveness of therapy. Although metabolic changes during cancer treatment are crucial determinant factors in therapeutic responses and toxicities, related clinical research remains limited. Methods One hundred paired blood samples were collected from 50 patients with LABC before and after a complete NACT treatment cycle. Untargeted metabolomics was used by liquid chromatography-mass spectrometry (LC–MS) to investigate the relationship between dynamically changing metabolites in serum and the responses and toxicities of NACT. Results Firstly, we observed significant alterations in serum metabolite levels pre- and post-NACT, with a predominant enrichment in the sphingolipid and amino acid metabolism pathways. Second, pre-treatment serum metabolites successfully predicted the therapeutic response and hematotoxicities during NACT. In particular, molecular subtype variations in favorable treatment responses are linked to acyl carnitine levels. Finally, we discovered that the therapeutic effects of NACT could be attributed to essential amino acid metabolism. Conclusion This study elucidated the dynamic changes in metabolism during NACT treatment, providing a possibility for developing responsive metabolic signatures for personalized NACT treatment.

Cyclo[18]carbon (C 18 ), which has been successfully synthesized and extensively studied, exhibits unique electronic transport properties. Cyclo[n]carbons (C n , n = 4k + 2), sharing a similar π-electron conjugation with C 18 , potentially...