Hepatocellular Brg1 promotes CCl4-induced liver inflammation, ECM accumulation and fibrosis in mice.

INTRODUCTION: Hepatic fibrosis is a progressive pathological process involving the exhaustion of hepatocellular regenerative capacity and ultimately leading to the development of cirrhosis and even hepatocellular carcinoma. Brg1, the core subunit of the SWI/SNF chromatin-remodeling complex, was recently identified as important for liver regeneration. This study investigates the role of Brg1 in hepatic fibrosis development. METHODS: Hepatocyte-specific Brg1 knockout mice were generated and injected with carbon tetrachloride (CCl4) for 4, 6, 8, and 12 weeks to induce liver fibrosis. Afterwards, liver fibrosis and liver damage were assessed. RESULTS: Brg1 expression was significantly increased in the fibrotic liver tissue of wild-type mice, as compared to that of untreated wild-type mice. The livers of the Brg1 knockout animals showed reduced liver inflammation, extracellular matrix accumulation, and liver fibrosis. TNF-α and NF-κB-mediated inflammatory response was reduced in Brg1 knockout animals. CONCLUSION: Brg1 promotes the progression of liver fibrosis in mice and may therefore be used as a potential therapeutic target for treating patients with liver fibrosis due to chronic injury.

Research on the Method of Counting Wheat Ears via Video Based on Improved YOLOv7 and DeepSort.

The number of wheat ears in a field is an important parameter for accurately estimating wheat yield. In a large field, however, it is hard to conduct an automated and accurate counting of wheat ears because of their density and mutual overlay. Unlike the majority of the studies conducted on deep learning-based methods that usually count wheat ears via a collection of static images, this paper proposes a counting method based directly on a UAV video multi-objective tracking method and better counting efficiency results. Firstly, we optimized the YOLOv7 model because the basis of the multi-target tracking algorithm is target detection. Simultaneously, the omni-dimensional dynamic convolution (ODConv) design was applied to the network structure to significantly improve the feature-extraction capability of the model, strengthen the interaction between dimensions, and improve the performance of the detection model. Furthermore, the global context network (GCNet) and coordinate attention (CA) mechanisms were adopted in the backbone network to implement the effective utilization of wheat features. Secondly, this study improved the DeepSort multi-objective tracking algorithm by replacing the DeepSort feature extractor with a modified ResNet network structure to achieve a better extraction of wheat-ear-feature information, and the constructed dataset was then trained for the re-identification of wheat ears. Finally, the improved DeepSort algorithm was used to calculate the number of different IDs that appear in the video, and an improved method based on YOLOv7 and DeepSort algorithms was then created to calculate the number of wheat ears in large fields. The results show that the mean average precision (mAP) of the improved YOLOv7 detection model is 2.5% higher than that of the original YOLOv7 model, reaching 96.2%. The multiple-object tracking accuracy (MOTA) of the improved YOLOv7-DeepSort model reached 75.4%. By verifying the number of wheat ears captured by the UAV method, it can be determined that the average value of an L1 loss is 4.2 and the accuracy rate is between 95 and 98%; thus, detection and tracking methods can be effectively performed, and the efficient counting of wheat ears can be achieved according to the ID value in the video.

Mir34a constrains pancreatic carcinogenesis.

Several studies have shown that over 70 different microRNAs are aberrantly expressed in pancreatic ductal adenocarcinoma (PDAC), affecting proliferation, apoptosis, metabolism, EMT and metastasis. The most important genetic alterations driving PDAC are a constitutive active mutation of the oncogene Kras and loss of function of the tumour suppressor Tp53 gene. Since the MicroRNA 34a (Mir34a) is a direct target of Tp53 it may critically contribute to the suppression of PDAC. Mir34a is epigenetically silenced in numerous cancers, including PDAC, where Mir34a down-regulation has been associated with poor patient prognosis. To determine whether Mir34a represents a suppressor of PDAC formation we generated an in vivo PDAC-mouse model harbouring pancreas-specific loss of Mir34a (KrasG12D; Mir34aΔ/Δ). Histological analysis of KrasG12D; Mir34aΔ/Δ mice revealed an accelerated formation of pre-neoplastic lesions and a faster PDAC development, compared to KrasG12D controls. Here we show that the accelerated phenotype is driven by an early up-regulation of the pro-inflammatory cytokines TNFA and IL6 in normal acinar cells and accompanied by the recruitment of immune cells. Our results imply that Mir34a restrains PDAC development by modulating the immune microenvironment of PDAC, thus defining Mir34a restauration as a potential therapeutic strategy for inhibition of PDAC development.

The neuropeptide receptor subunit RAMP1 constrains the innate immune response during acute pancreatitis in mice.

OBJECTIVES: The importance of the Calcitonin-gene-related-peptide-pathway (CGRP) as neuronal modulator of innate immune responses in mice has been previously demonstrated. The CGRP-receptor is composed of two subunits: the receptor-activity-modifying-protein-1 (RAMP1) and the calcitonin-receptor-like-receptor (CLR). CGRP can influence immune cells and their capacity of producing inflammatory cytokines. Using a RAMP1 knockout-mouse (RAMP1-/-) we examined the role of the CGRP-receptor in the acute-phase of cerulein-induced pancreatitis. METHODS: Hourly cerulein-injections for a period of 8 h in RAMP1-/- and wild-type mice were performed. To compare severity and extent of inflammation in RAMP1-/- and wild-type mice, histological analyses were done and cytokine levels were assessed using qRT-PCR 8 h, 24 h, 2 days, and 7 days post-cerulein-treatment. Furthermore, serum activities of LDH and lipase were determined. RESULTS: After 8 h RAMP1-/- mice showed a higher pancreas-to-body-weight-ratio, increased tissue edema and immune cell infiltration with higher amount of F4/80-positive cells as compared to wild-type mice. Overall infiltration of immune cells at 24 h was increased in RAMP1-/- mice and composed predominantly of MPO-positive neutrophils. In addition, after 24 h RAMP1-/- mice presented a higher pancreas-to-body-weight-ratio, higher expression of Ccl3, Il6, and Il1b and increased number of cleaved caspase 3 positive cells. Serum lipase correlated with the extent of tissue damage in RAMP1-/- compared to wild-type mice 24 h post-cerulein treatment. CONCLUSION: Mice lacking RAMP1 showed increased inflammation, tissue edema, and pancreas injury particularly in the early phase of acute pancreatitis. This study highlights the essential role of CGRP for dampening the innate immune response in acute pancreatitis.

Brg1 promotes liver regeneration after partial hepatectomy via regulation of cell cycle.

Brahma-related gene 1 (Brg1), a catalytic subunit of the SWItch/Sucrose Non-Fermentable (SWI/SNF) complex, is known to be involved in proliferative cell processes. Liver regeneration is initiated spontaneously after injury and leads to a strong proliferative response. In this study, a hepatocyte-specific Brg1 gene knockout mouse model was used to analyse the role of Brg1 in liver regeneration by performing a 70% partial hepatectomy (PH). After PH, Brg1 was significantly upregulated in wildtype mice. Mice with hepatocyte-specific Brg1 gene knockout showed a significantly lower liver to body weight ratio 48 h post-PH concomitant with a lower hepatocellular proliferation rate compared to wildtype mice. RNA sequencing demonstrated that Brg1 controlled hepatocyte proliferation through the regulation of the p53 pathway and several cell cycle genes. The data of this study reveal a crucial role of Brg1 for liver regeneration by promoting hepatocellular proliferation through modulation of cell cycle genes and, thus, identify Brg1 as potential target for therapeutic approaches.

BRG1 promotes hepatocarcinogenesis by regulating proliferation and invasiveness.

The chromatin remodeler complex SWI/SNF plays an important role in physiological and pathological processes. Brahma related gene 1(BRG1), a catalytic subunit of the SWI/SNF complex, is known to be mutated in hepatocellular carcinoma (HCC). However, its role in HCC remains unclear. Here, we investigate the role of BRG1 on cell growth and invasiveness as well as its effect on the expression of putative target genes. Expression of BRG1 was examined in human liver tissue samples and in HCC cell lines. In addition, BRG1 was silenced in human HCC cell lines to analyse cell growth and invasiveness by growth curves, colony formation assay, invasion assay and the expression of putative target genes. BRG1 was found to be significantly increased in HCC samples compared to non-HCC samples. In addition, a declined proliferation rate of BRG1-silenced human HCC cell lines was associated with a decrease of expression of cyclin family members. In line with a decreased invasiveness of BRG1-siRNA-treated human HCC cell lines, down-regulation of MMP7 was detected. These results support the hypothesis that overexpression of BRG1 increases cell growth and invasiveness in HCC. Furthermore, the data highlight cyclin B, E and MMP7 to be associated with BRG1 during hepatocarcinogenesis.

Hes1 Controls Exocrine Cell Plasticity and Restricts Development of Pancreatic Ductal Adenocarcinoma in a Mouse Model.

Perturbation of pancreatic acinar cell state can lead to acinar-to-ductal metaplasia (ADM), a precursor lesion to the development of pancreatic ductal adenocarcinoma (PDAC). In the pancreas, Notch signaling is active both during development and in adult cellular differentiation processes. Hes1, a key downstream target of the Notch signaling pathway, is expressed in the centroacinar compartment of the adult pancreas as well as in both preneoplastic and malignant lesions. In this study, we used a murine genetic in vivo approach to ablate Hes1 in pancreatic progenitor cells (Ptf1a+/Cre; Hes1fl/fl). Using this model, we studied the role of Hes1 in both acinar cell plasticity and pancreatic regeneration after caerulein-induced pancreatitis and in KrasG12D-driven PDAC development. We show that, although pancreatic development is not perturbed on the deletion of Hes1, terminal acinar differentiation in the adult pancreas is compromised. Moreover, the loss of Hes1 leads to the impaired regeneration of the exocrine compartment, accelerated fatty metaplasia, and persistent ADM after acute caerulein-induced pancreatitis. In KrasG12D-driven carcinogenesis, Hes1 ablation resulted in increased ADM, decreased formation of high-grade pancreatic intraepithelial neoplasias, and accelerated development of PDAC with shortened survival time. In conclusion, Hes1 plays a key role in acinar cell integrity and plasticity on cellular insults. Furthermore, Hes1 is an essential component of the pancreatic intraepithelial neoplasias-to-PDAC route in KrasG12D-driven mouse pancreatic carcinogenesis.

An armed oncolytic adenovirus ZD55-IL-24 combined with ADM or DDP demonstrated enhanced antitumor effect in lung cancer.

PURPOSE: Oncolytic adenovirus such as ZD55 has become a promising anticancer agent for its efficient tumor-targeted replication and lysis capability. Armed with therapeutic gene IL-24 to generate a novel oncolytic adenovirus ZD55-IL-24, the antitumor efficiency of ZD55 is greatly increased. To explore the clinical application of ZD55-IL-24 in cancer therapy, the combination of gene-virotherapy (ZD55-IL-24) with chemotherapy was performed in this paper. METHODS: The effect of this gene-virotherapy with chemotherapy on cell proliferation was determined by MTT assay in four types of cancer cell lines and one human normal cell line. Real-time PCR was performed to detect the replication of ZD55-IL-24 when adriamycin (ADM) or cisplatin (DDP) was administrated. The changes in caspase pathway were analyzed by Western blot. We further identify the combinational therapy in Balb/c nude mice with NCI-H460 xenograft. RESULTS: ADM and DDP enhanced cell killing/inhibiting effects of ZD55-IL-24 in all the tumor cell lines, while no overlapping toxicity was observed in the normal liver cell line L-02. These chemo-agents inhibited the propagation of ZD55-IL-24 in NCI-H460 cells, but did not influence the expression of IL-24. Consistent with the results in vitro, the tumor growth of co-administration group was remarkably delayed, compared with single treatment groups (p<0.05). CONCLUSION: ZD55-IL-24 combined with ADM demonstrates improved killing effects against lung tumor xenograft.

Potent antitumor effect of TRAIL mediated by a novel adeno-associated viral vector targeting to telomerase activity for human hepatocellular carcinoma.

BACKGROUND: Adeno-associated virus (AAV) has rapidly become a promising gene delivery vehicle for its excellent advantages of low pathogenicity and long-term gene expression. However, lack of tissue specificity caused low efficiency of AAV transfer to target cells. The promoter of human telomerase reverse transcriptase (hTERT) has been implicated in mediating gene expression in cancer cells as hTERT is transcriptionally upregulated in most cancer cells. Thereby, the hTERT promoter becomes a good candidate to enhance the targeting efficiency of AAV in cancer cells. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) functions as a soluble cytokine to selectively kill various cancer cells without toxicity to most normal cells. It remains to be determined whether the hTERT promoter can efficiently mediate TRAIL gene therapy in cancer cells using AAV vector. METHODS: A novel AAV vector containing the TRAIL gene under the control of the hTERT promoter (AAV-hTERT-TRAIL) was generated. The specific expression of hTERT-controlled genes was evaluated in cell lines. The antitumor efficacy of AAV-hTERT-TRAIL was assessed in tumor cell lines and human hepatocellular carcinoma xenograft mouse model. RESULTS: TRAIL expression was observed in tumor cells infected with AAV-hTERT-TRAIL at both the protein and mRNA level. AAV-hTERT-TRAIL displayed cancer-specific cytotoxicity and induced tumor cell apoptosis. Moreover, in animal experiments, intratumoral administration of AAV-hTERT-TRAIL significantly suppressed the growth of xenograft tumors and resulted in tumor cell death. CONCLUSIONS: AAVs in combination with hTERT-mediated therapeutic gene expression provide a promising targeting approach for developing effective therapy for human cancers. These data suggest that AAV-hTERT-TRAIL is a potent therapeutic agent for cancer therapy.

Enhanced sensitivity of hepatocellular carcinoma cells to chemotherapy with a Smac-armed oncolytic adenovirus.

AIM: The aim of the present study was to further improve the therapeutic effects for human hepatocellular carcinoma (HCC) and reduce the damage in normal cells using a novel chemo-gene-virotherapeutic strategy. METHODS: An oncolytic adenoviral vector (ZD55) similar to the typical oncolytic adenovirus ONYX-015, with a deletion of E1B-55K gene, was employed to express the second mitochondria-derived activator of caspases (Smac) protein by constructing a recombinant virus ZD55-Smac. The enhanced cytotoxicity of the combined treatment of ZD55-Smac with cisplatin or 5-fluorouracil (5-FU) was evaluated in several HCC cell lines. Moreover, the negative effects on normal cells have been tested in human normal liver cell lines L-02 and QSG-7701 cell lines by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and apoptotic cell staining. RESULTS: According to our observation, ZD55-Smac is superior to ONYX-015 in sensitizing chemotherapy, ZD55-Smac used in conjunction with chemotherapy was found to exhibit obviously enhanced cytotoxicity in HCC cells, yet significantly abolished the negative toxicity in normal cells by utilizing the tumor selective replication vector and reducing the dosage. CONCLUSION: This chemo-gene-virotherapeutic (cisplatin or 5-FU+ZD55-Smac) strategy is superior to the conventional chemo-gene or chemo-viro approach.