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Heat shock protein (HSP) 40 has emerged as a key actor in both innate and adaptive immunity, whereas the role of HLJ1, a molecular chaperone in HSP40 family, in modulating endotoxin–induced sepsis severity is still unclear. Here, we use single-cell RNA sequencing to characterize mouse liver nonparenchymal cell populations under LPS (lipopolysaccharide) stimulation, and show that HLJ1 deletion affected IFN-γ-related gene signatures in distinct immune cell clusters. HLJ1 deficiency also leads to reduced serum levels of IL-12 in LPS-treated mice, contributing to dampened production of IFN-γ in natural killer cells but not CD4+ or CD8+ T cells, and subsequently to improved survival rate. Adoptive transfer of HLJ1-deleted macrophages into LPS-treated mice results in reduced IL-12 and IFN-γ levels and protects the mice from IFN-γ–dependent mortality. In the context of molecular mechanisms, HLJ1 is an LPS-inducible protein in macrophages and converts misfolded IL-12p35 homodimers to monomers, which maintains bioactive IL-12p70 heterodimerization and secretion. This study suggests HLJ1 causes IFN-γ–dependent septic lethality by promoting IL-12 heterodimerization, and targeting HLJ1 has therapeutic potential in inflammatory diseases involving activating IL-12/IFN-γ axis.

Heat shock protein (HSP) 40 has emerged as a key factor in both innate and adaptive immunity, whereas the role of HLJ1, a molecular chaperone in HSP40 family, in modulating endotoxin-induced sepsis severity is still unclear. During lipopolysaccharide (LPS)-induced endotoxic shock, HLJ1 knockout mice shows reduced organ injury and IFN-γ (interferon-γ)-dependent mortality. Using single-cell RNA sequencing, we characterize mouse liver nonparenchymal cell populations under LPS stimulation, and show that HLJ1 deletion affected IFN-γ-related gene signatures in distinct immune cell clusters. In CLP models, HLJ1 deletion reduces IFN-γ expression and sepsis mortality rate when mice are treated with antibiotics. HLJ1 deficiency also leads to reduced serum levels of IL-12 in LPS-treated mice, contributing to dampened production of IFN-γ in natural killer cells but not CD4+or CD8+T cells, and subsequently to improved survival rate. Adoptive transfer of HLJ1-deleted macrophages into LPS-treated mice results in reduced IL-12 and IFN-γ levels and protects the mice from IFN-γ-dependent mortality. In the context of molecular mechanisms, HLJ1 is an LPS-inducible protein in macrophages and converts misfolded IL-12p35 homodimers to monomers, which maintains bioactive IL-12p70 heterodimerization and secretion. This study suggests HLJ1 causes IFN-γ-dependent septic lethality by promoting IL-12 heterodimerization, and targeting HLJ1 has therapeutic potential in inflammatory diseases involving activated IL-12/IFN-γ axis.

Liver cancer is the sixth most common cancer and the fourth leading cause of cancer-related death worldwide. The conventional treatments such as surgical resection and liver transplantation are applicable to only a small proportion of patients and prolongation of survival is restricted. Therefore, it is urgent to develop cancer biomarkers for defining cancer risk, diagnosis, prognosis and even find new therapeutic targets. Human Liver DnaJ-Like Protein (HLJ1), which belongs to DnaJ heat shock protein family (HSP40) member B4 (DNAJB4), has been reported to act as a tumor suppressor in NSCLC, colorectal cancer, melanoma metastasis. However, the precise role of HLJ1 in liver cancer tumorigenesis and the progress of HCC carcinogenesis has not been elucidated yet. Thus, we investigate whether HLJ1 has tumor-suppressive or oncogenic role on DEN-induced liver cancer development in a mouse model. Wild-type (WT) and HLJ1 knockout (HLJ1−/−) mice are injected with 20 mg/kgbw DEN at postnatal day 15. Thereafter, 50 mg/kgbw DEN is administrated weekly to mice between age 4 to 12 weeks. Mice were sacrificed at age 30 and 36 weeks to assess the tumor count and size. In another group, mice are injected with DEN and age day 15 and then 500 ppm PB is administrated in drinking water until mice were sacrifice at age 52 weeks. The liver tissues are frozen and fixed for western blotting and IHC analysis. For cDNA microarray analysis, gene expression microarray samples were from 6-8 weeks wild-type and HLJ1−/− mice livers. When sacrificed at age 30 and 36 weeks, HLJ1−/− mice exhibited higher tumor multiplicity, serum ALT, AST levels, and larger macroscopic tumor nodules than WT mice. In DEN+PB treatment group, higher incidence rate can be observed in HLJ1−/− mice than in WT mice. This indicated HLJ1 protects liver from DEN-induced HCC carcinogenesis and knockout of HLJ1 confers to more severe HCC induction. Furthermore, p-STAT3 expression was higher in normal part of HLJ1−/− mice liver compared to that of WT mice liver, which suggest the role of HLJ1 in regulating p-STAT3 signaling in the early stage of tumor formation. Using IHC staining and western blotting to analyze HLJ1 expression level, we found half of the tumors express higher HLJ1 than adjacent normal part did, which suggested a tumor-promoting role of HLJ1 after tumor initiation and formation. In cDNA microarray analysis, network analysis of genes enriched in HCC map folder revealed involved objects JunB, c-Myc, p21 and Cyclin D1, which was further confirmed by quantitative PCR. p21 and Cyclin D1 were highly expressed in the liver of HLJ1−/− comparing to that of WT mice, which suggested HLJ1-related genes p21 and Cyclin D1 may have roles in HCC formation. Clinical information of 362 liver cancer patients from TCGA database exhibited that higher expression of HLJ1 in tumor part is correlated to lower disease-specific survival rate. It indicated that HLJ1 may be a tumor marker for HCC prognosis and clinical outcome prediction. It also suggested that HLJ1 may play an oncogenic role after tumor formation. In summary, HLJ1 has protective role against DEN-induced hepatocarcinogenesis through down-regulated p-STAT3 and cyclin D1 whereas it could also be an enhancer to promote tumor progression after tumor formation. Hence, HLJ1 could be a target for liver cancer therapy and a prognostic biomarker in the future. Citation Format: Wei-Jia Luo, Min-Hui Chien, Jeremy J. W. Chen, Sung-Liang Yu, Pan-Chyr Yang, Kang-Yi Su. HLJ1 deficiency enhanced diethylnitrosamine-induced hepatocarcinogenesis in a gene targeting mouse model [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5972.

Background: Obesity is a serious health problem worldwide. The correlation of obesity and chronic diseases and cancer been well-documented. Although obesity can promote cancer progression, the mechanism is largely unknown and thus an ideal animal model is required especially in lung cancer. Methods: We utilized an inducible mutant EGFR driven lung cancer transgenic mouse to address this issue. Mice with lung cancer induction were fed with regular diet (RD) or high-fat diet (HFD) followed by tumor burden evaluation. Lung tissues were harvested for whole-genome transcriptomic, gene enrichment analysis, and cytokine array for potential signatures identification. Findings: Mice with HFD treatments had significant body weight increments compared with RD treatments (p 2-fold, p

to investigate the effect of isochaihulactone (also known as K8), a lignan compound of Bupleurum scorzonerifolium, on H(2)O(2)-induced cytotoxicity in neuronally differentiated PC12 cells (nPC12).viability of neuronal PC12 cells was measured using MTT assay. Protein expression was determined by Western blot. Apoptotic cells was determined using TUNEL assay. D-galactose aging mice were used as a model system to study the anti-oxidant effects of isochaihulactone in vivo.pretreatment with isochaihulactone (5-10 micromol/L) increased cell viability and decreased membrane damage, generation of reactive oxygen species and degradation of poly (ADP-ribose) polymerase in H(2)O(2)-treated nPC12 cells and also decreased the expression of cyclooxygenase-2, via downregulation of NF-kappaB, resulting in a decrease in lipid peroxidation. The results suggest that isochaihulactone is a potential antioxidant agent. In a murine aging model, in which chronic systemic exposure to D-galactose (D-gal) causes the acceleration of senescence, administration of isochaihulactone (10 mgxkg(-1)xd(-1), sc) for 7 weeks concomitant with D-gal injection significantly increased superoxide dismutase and glutathione peroxidase activities and decreased the MDA level in plasma. Furthermore, HE staining to quantify cell death within hippocampus showed that percentage of pyknotic nuclei in the D-gal-treated mice were much higher than in control.the results suggest that isochaihulactone exerts potent anti-aging effects against D-gal in mice possibly via antioxidative mechanisms.