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JCI Insight Apr 2019The immune system detects aberrant, premalignant cells and eliminates them before the development of cancer. Immune cells, including T cells, have been shown to be...
The immune system detects aberrant, premalignant cells and eliminates them before the development of cancer. Immune cells, including T cells, have been shown to be critical components in eradicating these aberrant cells, and when absent in the host, incidence of cancer increases. Here, we show that CD91, a receptor expressed on antigen-presenting cells, is required for priming immune responses to nascent, emerging tumors. In the absence of CD91, effector immune responses are subdued, and tumor incidence and progression are amplified. We also show that, consequently, tumors that arise in the absence of CD91 express neo-epitopes with indices that are indicative of greater immunogenicity. Polymorphisms in human CD91 that are expected to affect ligand binding are shown to influence antitumor immune responses in cancer patients. This study presents a molecular mechanism for priming immune responses to nascent, emerging tumors that becomes a predictor of cancer susceptibility and progression.
Topics: Animals; Antigen Presentation; Antigens, Neoplasm; Carcinoma, Squamous Cell; Cross-Priming; Dendritic Cells; Epitope Mapping; Epitopes, T-Lymphocyte; Female; Humans; Immunologic Surveillance; Low Density Lipoprotein Receptor-Related Protein-1; Lung Neoplasms; Melanoma; Methylcholanthrene; Mice; Mice, Knockout; Neoplasms, Experimental; Polymorphism, Single Nucleotide; Protein Domains; Protein Stability; Skin Neoplasms; Exome Sequencing
PubMed: 30944251
DOI: 10.1172/jci.insight.127239 -
BioRxiv : the Preprint Server For... Jan 2024Radiation therapy is frequently used to treat cancers including soft tissue sarcomas. Prior studies established that the toll-like receptor 9 (TLR9) agonist...
Radiation therapy is frequently used to treat cancers including soft tissue sarcomas. Prior studies established that the toll-like receptor 9 (TLR9) agonist cytosine-phosphate-guanine oligodeoxynucleotide (CpG) enhances the response to radiation therapy (RT) in transplanted tumors, but the mechanism(s) remain unclear. Here, we used CRISPR/Cas9 and the chemical carcinogen 3-methylcholanthrene (MCA) to generate autochthonous soft tissue sarcomas with high tumor mutation burden. Treatment with a single fraction of 20 Gy RT and two doses of CpG significantly enhanced tumor response, which was abrogated by genetic or immunodepletion of CD8+ T cells. To characterize the immune response to RT + CpG, we performed bulk RNA-seq, single-cell RNA-seq, and mass cytometry. Sarcomas treated with 20 Gy and CpG demonstrated increased CD8 T cells expressing markers associated with activation and proliferation, such as Granzyme B, Ki-67, and interferon-γ. CpG + RT also upregulated antigen presentation pathways on myeloid cells. Furthermore, in sarcomas treated with CpG + RT, TCR clonality analysis suggests an increase in clonal T-cell dominance. Collectively, these findings demonstrate that RT + CpG significantly delays tumor growth in a CD8 T cell-dependent manner. These results provide a strong rationale for clinical trials evaluating CpG or other TLR9 agonists with RT in patients with soft tissue sarcoma.
PubMed: 38260522
DOI: 10.1101/2024.01.03.573968 -
Journal of Occupational Health Jan 2018This report reviews the carcinogenicity of multi-walled carbon nanotubes (MWCNTs) in experimental animals, concentrating on MWNT-7, a straight fibrous MWCNT.
OBJECTIVES
This report reviews the carcinogenicity of multi-walled carbon nanotubes (MWCNTs) in experimental animals, concentrating on MWNT-7, a straight fibrous MWCNT.
METHODS
MWCNTs were administered to mice and rats by intraperitoneal injection, intrascrotal injection, subcutaneous injection, intratracheal instillation and inhalation.
RESULTS
Intraperitoneal injection of MWNT-7 induced peritoneal mesothelioma in mice and rats. Intrascrotal injection induced peritoneal mesothelioma in rats. Intratracheal instillation of MWCNT-N (another straight fibrous MWCNT) induced both lung carcinoma and pleural mesothelioma in rats. In the whole body inhalation studies, in mice MWNT-7 promoted methylcholanthrene-initiated lung carcinogenesis. In rats, inhalation of MWNT-7 induced lung carcinoma and lung burdens of MWNT-7 increased with increasing concentration of airborne MWNT-7 and increasing duration of exposure.
CONCLUSIONS
Straight, fibrous MWCNTs exerted carcinogenicity in experimental animals. Phagocytosis of MWCNT fibers by macrophages was very likely to be a principle factor in MWCNT lung carcinogenesis. Using no-observed-adverse-effect level-based approach, we calculated that the occupational exposure limit (OEL) of MWNT-7 for cancer protection is 0.15 μg/m for a human worker. Further studies on the effects of the shape and size of MWCNT fibers and mode of action on the carcinogenicity are required.
Topics: Animals; Carcinogenesis; Carcinoma; Humans; Inhalation Exposure; Lung; Lung Neoplasms; Maximum Allowable Concentration; Mesothelioma; Mesothelioma, Malignant; Mice; Nanotubes, Carbon; Occupational Exposure; Peritoneal Neoplasms; Phagocytosis; Pleural Neoplasms; Rats
PubMed: 29046510
DOI: 10.1539/joh.17-0102-RA -
Molecular and Cellular Biology Oct 2019Transgenic mice expressing a constitutively active form of the aryl hydrocarbon receptor in keratinocytes (AhR-CA mice) develop severe dermatitis that substantially...
Transgenic mice expressing a constitutively active form of the aryl hydrocarbon receptor in keratinocytes (AhR-CA mice) develop severe dermatitis that substantially recapitulates the pathology of human atopic dermatitis. The neurotrophic factor artemin (Artn) is highly expressed in the epidermis of AhR-CA mice and causes hypersensitivity to itch (alloknesis) by elongating nerves into the epidermis. However, whether the gene is regulated directly by AhR or indirectly through complex regulation associated with AhR remains unclear. To this end, we previously conducted chromatin immunoprecipitation-sequencing analyses of the locus and found a xenobiotic response element (XRE) motif located far upstream (52 kb) of the gene. Therefore, in this study, we addressed whether the XRE actually regulates the gene expression by deleting the region containing the motif. We generated two lines of Artn mice. In the mouse epidermis, inducible expression of the gene by the AhR agonist 3-methylcholanthrene was substantially suppressed compared to that in wild-type mice. Importantly, in AhR-CA::Artn mice, expression was significantly suppressed, and alloknesis was improved. These results demonstrate that the gene is indeed regulated by the distal XRE-containing enhancer, and alloknesis in AhR-CA mice is provoked by the AhR-mediated direct induction of the gene.
Topics: Air Pollutants; Animals; Antibodies, Neutralizing; Basic Helix-Loop-Helix Transcription Factors; Dermatitis, Atopic; Enhancer Elements, Genetic; Gene Expression Regulation; Humans; Methylcholanthrene; Mice, Inbred C57BL; Mice, Transgenic; Nerve Tissue Proteins; Receptors, Aryl Hydrocarbon; Response Elements; Skin; Xenobiotics
PubMed: 31358547
DOI: 10.1128/MCB.00190-19 -
The Journal of Toxicological Sciences 2021The aryl hydrocarbon receptor (AhR) regulates expression of genes encoding drug/xenobiotic metabolizing enzymes. Cytochrome P450 (CYP) 3A5 is involved in drug...
The aryl hydrocarbon receptor (AhR) regulates expression of genes encoding drug/xenobiotic metabolizing enzymes. Cytochrome P450 (CYP) 3A5 is involved in drug metabolism. However, regulation of CYP3A5 gene expression is not yet well understood. In this study, we aimed to investigate the effect of the ligands of AhR on CYP3A5 gene expression. CYP3A5 mRNA expression was induced by the polycyclic aromatic hydrocarbons (PAHs) such as 3-methylcholanthrene (3MC) and benzo[a]pyrene in HepG2 cells. To determine whether the PAHs induced CYP3A5 gene expression via AhR, we generated AhR knockout (AhR KO) HepG2 cells. CYP3A5 mRNA expression was not induced by 3MC treatment in AhR KO cells. In addition, we generated AhR rescue cells from AhR KO cells and evaluated CYP3A5 mRNA expression. We found that CYP3A5 mRNA expression was induced by 3MC treatment in AhR rescue cells. Taken together, these results demonstrated that CYP3A5 mRNA expression was induced by PAHs via AhR in HepG2 cells. Our findings suggest that ligand-activated AhR affects CYP3A5-mediated drug metabolism.
Topics: Basic Helix-Loop-Helix Transcription Factors; Cytochrome P-450 CYP3A; Gene Expression; Hep G2 Cells; Humans; Ligands; Polycyclic Aromatic Hydrocarbons; RNA, Messenger; Receptors, Aryl Hydrocarbon
PubMed: 33408298
DOI: 10.2131/jts.46.25 -
Journal of Genetics Dec 2018To analyse the mechanism of tumourigenic transformation of NIH3T3 cells at the transcriptional level, we used cancerogen 3-methylcholanthrene (3-MCA) and cancerogenic...
To analyse the mechanism of tumourigenic transformation of NIH3T3 cells at the transcriptional level, we used cancerogen 3-methylcholanthrene (3-MCA) and cancerogenic substance phorbol-12-myristate-13-acetate (PMA) to transform NIH3T3 cells and the assessment of transformation was performed using Giemsa staining and methylcellulose colony formation assay. Changes in gene expression profile were detected by Mouse Genome 430 2.0 microarray; and quantitative real-time polymerase chain reaction and Western blotting were used to verify the expression changes of mRNAs and proteins, respectively. With the aid of bioinformatics method, five signalling pathways were identified to participate in different stages of NIH3T3 cell transformation. Further, our study suggested that oncogenes , , and the tumour suppressor gene may play important roles in these pathways.
Topics: Animals; Biomarkers, Tumor; Cell Transformation, Neoplastic; Cyclin A1; Gene Expression Profiling; Mice; NIH 3T3 Cells; Phosphoprotein Phosphatases; Proto-Oncogene Proteins c-jun; Proto-Oncogene Proteins c-myc
PubMed: 30555065
DOI: No ID Found -
Archives of Toxicology Jan 2022Error-corrected sequences (ECSs) that utilize double-stranded DNA sequences are useful in detecting mutagen-induced mutations. However, relatively higher frequencies of...
Error-corrected sequences (ECSs) that utilize double-stranded DNA sequences are useful in detecting mutagen-induced mutations. However, relatively higher frequencies of G:C > T:A (1 × 10 bp) and G:C > C:G (2 × 10 bp) errors decrease the accuracy of detection of rare G:C mutations (approximately 10 bp). Oxidized guanines in single-strand (SS) overhangs generated after shearing could serve as the source of these errors. To remove these errors, we first computationally discarded up to 20 read bases corresponding to the ends of the DNA fragments. Error frequencies decreased proportionately with trimming length; however, the results indicated that they were not sufficiently removed. To efficiently remove SS overhangs, we evaluated three mechanistically distinct SS-specific nucleases (S1 Nuclease, mung bean nuclease, and RecJf exonuclease) and found that they were more efficient than computational trimming. Consequently, we established Jade-Seq™, an ECS protocol with S1 Nuclease treatment, which reduced G:C > T:A and G:C > C:G errors to 0.50 × 10 bp and 0.12 × 10 bp, respectively. This was probably because S1 Nuclease removed SS regions, such as gaps and nicks, depending on its wide substrate specificity. Subsequently, we evaluated the mutation-detection sensitivity of Jade-Seq™ using DNA samples from TA100 cells exposed to 3-methylcholanthrene and 7,12-dimethylbenz[a]anthracene, which contained the rare G:C > T:A mutation (i.e., 2 × 10 bp). Fold changes of G:C > T:A compared to the vehicle control were 1.2- and 1.3-times higher than those of samples without S1 Nuclease treatment, respectively. These findings indicate the potential of Jade-Seq™ for detecting rare mutations and determining the mutagenicity of environmental mutagens.
Topics: DNA; DNA Repair; High-Throughput Nucleotide Sequencing; Mutagens; Mutation
PubMed: 34767040
DOI: 10.1007/s00204-021-03185-y -
Oncology Letters Mar 2016Animal models play a key role in identifying treatments for various types of cancer, including lung cancer. The aim of the present study was to develop a new animal...
Animal models play a key role in identifying treatments for various types of cancer, including lung cancer. The aim of the present study was to develop a new animal model for lung cancer induction using tree shrews from the Yunnan region in China. Tree shrews are suitable for a full simulation of human disease because their structure, function and metabolism are adequately close to human. This animal may offer a new experimental animal model to be used in the study of lung cancer. In the present study, 80 healthy tree shrews were distributed in experimental and control groups. Animals in the experimental group received different concentrations of iodized oil suspension of 3-methylcholanthrene (3-MC) and diethylnitrosamine (DEN) while animals in the control groups received saline or lipiodol solvent via endotracheal instillation. In the 3rd, 5th, 7th, 9th and 11th weeks the body weights of the animals were measured and chest X-ray examinations were conducted. Pathological studies on the lung tissues were also performed and the pathological changes occurring in bronchial epithelium in all the groups were examined. Animals in the experimental group gradually lost their body weight. For tree shrews in the blank control and solvent control groups the survival rates were 100 and 80%, respectively while the survival rate for the experimental group was 0%. Results from the chest X-ray conducted on animals in the blank control and solvent control groups revealed no obvious abnormalities while in the experimental group high-density shadow spots within the perfusion sites were observed. Pathological studies performed on these high-density areas confirmed changes in the bronchial epithelium. In the experimental groups we also detected bronchial epithelial atypical hyperplasia, and apparent changes in carcinoma . In conclusion, lung cancer was successfully induced in tree shrews by a one-time endotracheal introduction of iodized oil suspension of 3-MC and DEN.
PubMed: 26998127
DOI: 10.3892/ol.2016.4156 -
Cell Biology and Toxicology Jan 20243-Methylcholanthracene (3-MC) is one of the most carcinogenic polycyclic aromatic hydrocarbons (PAHs). Long-term exposure to PAHs has been thought of as an important...
3-Methylcholanthracene (3-MC) is one of the most carcinogenic polycyclic aromatic hydrocarbons (PAHs). Long-term exposure to PAHs has been thought of as an important factor in urothelial tumorigenesis. N-methyladenosine (mA) exists widely in eukaryotic organisms and regulates the expression level of specific genes by regulating mRNA stability, translation efficiency, and nuclear export efficiency. Currently, the potential molecular mechanisms that regulate mA modification for 3-MC carcinogenesis remain unclear. Here, we profiled mRNA, mA, translation and protein level using "-omics" methodologies, including transcriptomes, mA profile, translatomes, and proteomics in 3-MC-transformed urothelial cells and control cells. The key molecules SLC3A2/SLC7A5 were screened and identified in 3-MC-induced uroepithelial transformation. Moreover, SLC7A5/SLC3A2 promoted uroepithelial cells malignant phenotype in vitro and in vivo. Mechanically, METTL3 and ALKBH5 mediated mA modification of SLC3A2/SLC7A5 mRNA in 3-MC-induced uroepithelial transformation by upregulating the translation of SLC3A2/SLC7A5. Furthermore, programmable mA modification of SLC3A2/SLC7A5 mRNA affected the expression of its proteins. Taken together, our results revealed that the mA modification-mediated SLC3A2/SLC7A5 translation promoted 3-MC-induced uroepithelial transformation, suggesting that targeting mA modification of SLC3A2/SLC7A5 may be a potential therapeutic strategy for bladder cancer related to PAHs.
Topics: Humans; Large Neutral Amino Acid-Transporter 1; Methylcholanthrene; Carcinogenesis; Cell Transformation, Neoplastic; Polycyclic Aromatic Hydrocarbons; RNA, Messenger; Methyltransferases; Fusion Regulatory Protein 1, Heavy Chain
PubMed: 38267663
DOI: 10.1007/s10565-024-09846-9 -
Drug Metabolism and Disposition: the... Dec 2015Emerging evidence indicates that the aryl hydrocarbon receptor (AhR) plays a crucial role in normal physiologic homeostasis. Additionally, aberrant AhR signaling leads...
Emerging evidence indicates that the aryl hydrocarbon receptor (AhR) plays a crucial role in normal physiologic homeostasis. Additionally, aberrant AhR signaling leads to several pathologic states in the lung and liver. Activation of AhR transcriptionally induces phase I (CYP1A) detoxifying enzymes. Although the effects of the classic AhR ligands such as 3-methylcholanthrene and dioxins on phase 1 enzymes are well studied in rodent lung, liver, and other organs, the toxicity profiles limit their use as therapeutic agents in humans. Hence, there is a need to identify and investigate nontoxic AhR ligands not only to understand the AhR biology but also to develop the AhR as a clinically relevant therapeutic target. Leflunomide is a Food and Drug Administration-approved drug in humans that is known to have AhR agonist activity in vitro. Whether it activates AhR and induces phase 1 enzymes in vivo is unknown. Therefore, we tested the hypothesis that leflunomide will induce pulmonary and hepatic CYP1A enzymes in C57BL/6J wild-type mice, but not in AhR-null mice. We performed real-time reverse-transcription polymerase chain reaction analyses for CYP1A1/2 mRNA expression, western blot assays for CYP1A1/2 protein expression, and ethoxyresorufinO-deethylase assay for CYP1A1 catalytic activity. Leflunomide increased CYP1A1/A2 mRNA, protein, and enzymatic activities in wild-type mice. In contrast, leflunomide failed to increase pulmonary and hepatic CYP1A enzymes in AhR-null mice. In conclusion, we provide evidence that leflunomide induces pulmonary and hepatic CYP1A enzymes via the AhR.
Topics: Animals; Basic Helix-Loop-Helix Transcription Factors; Cytochrome P-450 CYP1A1; Cytochrome P-450 CYP1A2; Cytochrome P-450 Enzyme Inducers; Female; Isoxazoles; Leflunomide; Liver; Lung; Mice; Mice, Inbred C57BL; Mice, Knockout; Receptors, Aryl Hydrocarbon
PubMed: 26417045
DOI: 10.1124/dmd.115.066084