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Proceedings of the National Academy of... Jan 2018Exposure of certain cell lines to methylcholanthrene, X-rays, or physiological growth constraint leads to preneoplastic transformation in all or most of the treated... (Review)
Review
Exposure of certain cell lines to methylcholanthrene, X-rays, or physiological growth constraint leads to preneoplastic transformation in all or most of the treated cells. After attaining confluence, a fraction in those cells progress to full transformation, as evidenced by their ability to form discrete foci distinguishable from the surrounding cells by virtue of their higher density. Transformation induced by suspension in agar, an even stronger growth-selective condition than confluence, is reminiscent of all but the final differentiated stage of a normal developmental process, epithelial-mesenchymal transition. Changes associated with transformation are not restricted to focus-forming cells, as the permissiveness for focus formation provided by confluent cells surrounding transformed foci is greater than that of nonselected cells. The neoplastic process can also be reversed in culture. Transformed cells passaged at low density in high serum revert to normal morphology and growth behavior in vitro and lose the capacity for tumor formation in vivo. We propose that transformation and its reversal are driven by a process of phenotypic selection that involves entire heterogeneous populations of cells responding to microenvironmental changes. Because of the involvement of whole cell populations, we view this process as fundamentally adaptive and epigenetic in nature.
Topics: Adaptation, Biological; Animals; Cell Transformation, Neoplastic; Cellular Microenvironment; Epigenesis, Genetic; Phenotype; Selection, Genetic
PubMed: 29311337
DOI: 10.1073/pnas.1717299115 -
Oncotarget Oct 2017Polyamines have been widely investigated as potential biomarkers for various types of cancers, including lung cancer, which is one of the most common causes of death...
Polyamines have been widely investigated as potential biomarkers for various types of cancers, including lung cancer, which is one of the most common causes of death from cancer worldwide. This study was carried out to evaluate the value of polyamines that serve as early diagnostic and cancer progression markers as well as drug evaluation for lung cancer (squamous cell carcinoma of lung, SCCL). SCCL was induced in Wistar rats by intratracheal instillation of 3-methylcholanthrene and treated with three different anti-cancer drugs, Aidi injections, fluorouracil, and a combination of them. After carcinogenesis for 28, 70 and 98 days and therapy for 28 and 56 days, the polyamine levels in plasma of SCCL, healthy and treated rats were determined using a UHPLC-MS/MS assay base on the means of targeted metabolomics. Results showed that increased N-acetylputrescine, cadaverine and 1,3-diaminopropane levels were associated with progression of SCCL. The levels of cadaverine and 1,3-diaminopropane returned to normal after administration of the three different kinds of anticancer drug. In addition, the suitability of using N-acetylputrescine, cadaverine and 1,3-diaminopropane as biomarkers was confirmed by PLS-DA and ROC analysis. It can provide an innovative and effective way for the clinical diagnosis, prevention and treatment of lung cancer, and stimulate a theoretical basis for the design and development of new anticancer drugs. At the same time, this increased the clinical options for polyamines as cancer biomarkers.
PubMed: 29179458
DOI: 10.18632/oncotarget.19304 -
British Journal of Cancer Jan 2018We investigated the role of prostaglandin receptors (e.g. prostaglandin E2 receptor 2 (EP2), EP4) and the efficacy of celecoxib in urothelial tumourigenesis and cancer...
BACKGROUND
We investigated the role of prostaglandin receptors (e.g. prostaglandin E2 receptor 2 (EP2), EP4) and the efficacy of celecoxib in urothelial tumourigenesis and cancer progression.
METHODS
We performed immunohistochemistry in bladder cancer (BC) tissue microarrays, in vitro transformation assay in a normal urothelial SVHUC line, and western blot/reverse transcription-polymerase chain reaction/cell growth assays in BC lines.
RESULTS
EP2/EP4 expression was elevated in BCs compared with non-neoplastic urothelial tissues and in BCs from those who were resistant to cisplatin-based neoadjuvant chemotherapy. Strong positivity of EP2/EP4 in non-muscle-invasive tumours or positivity of EP2/EP4 in muscle-invasive tumours strongly correlated with disease progression or disease-specific mortality, respectively. In SVHUC cells, exposure to a chemical carcinogen 3-methylcholanthrene considerably increased and decreased the expression of EP2/EP4 and phosphatase and tensin homologue (PTEN), respectively. Treatment with selective EP2/EP4 antagonist or celecoxib also resulted in prevention in 3-methylcholanthrene-induced neoplastic transformation of SVHUC cells. In BC lines, EP2/EP4 antagonists and celecoxib effectively inhibited cell viability and migration, as well as augmented PTEN expression. Furthermore, these drugs enhanced the cytotoxic activity of cisplatin in BC cells. EP2/EP4 and PTEN were also elevated and reduced, respectively, in cisplatin-resistant BC sublines.
CONCLUSIONS
EP2/EP4 activation correlates with induction of urothelial cancer initiation and outgrowth, as well as chemoresistance, presumably via downregulating PTEN expression.
Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cisplatin; Drug Resistance, Neoplasm; Heterografts; Humans; Immunohistochemistry; Male; Mice; Mice, Inbred NOD; Mice, SCID; Neoplasm Invasiveness; PTEN Phosphohydrolase; Receptors, Prostaglandin; Tissue Array Analysis; Urinary Bladder Neoplasms
PubMed: 29123257
DOI: 10.1038/bjc.2017.393 -
American Journal of Cancer Research 2017Emerging preclinical evidence suggests the critical role of androgen-mediated androgen receptor (AR) signals in the development of bladder cancer. However, little is...
Emerging preclinical evidence suggests the critical role of androgen-mediated androgen receptor (AR) signals in the development of bladder cancer. However, little is known about the efficacy of enzalutamide, an AR signaling inhibitor, in androgen-induced urothelial tumorigenesis. We therefore aimed to assess the effects of enzalutamide on neoplastic transformation of urothelial cells. An immortalized normal urothelial cell line SVHUC stably expressing wild-type AR (SVHUC-AR) was exposed to a chemical carcinogen 3-methylcholanthrene (MCA) to induce neoplastic transformation, and subsequently cultured for 6 weeks in the presence of anti-androgens, including enzalutamide, hydroxyflutamide, and bicalutamide. Tumorigenesis was then monitored, using plate and soft agar colony formation assays as well as mouse xenograft models. In SVHUC-AR cells exposed to MCA, each anti-androgen inhibited AR-mediated transcriptional activity, but only enzalutamide prevented AR nuclear translocation. transformation showed that treatment with each anti-androgen during the process of neoplastic transformation reduced the efficiency of colony formation . Compared with mock treatment, culture with enzalutamide ( = 0.028), hydroxyflutamide ( = 0.033), or bicalutamide ( = 0.038) also resulted in prevention/retardation of tumor formation in male NOD-SCID mice. In addition, anti-androgens up-regulated the expression of several molecules that play a protective role in bladder tumorigenesis, including , , and , and down-regulated that of several oncogenic genes, such as , and , in MCA-exposed SVHUC-AR cells. Thus, enzalutamide, flutamide, and bicalutamide were found to similarly prevent neoplastic transformation of urothelial cells. These findings offer a potential chemopreventive approach for urothelial tumors using AR antagonists.
PubMed: 29119053
DOI: No ID Found -
Archives of Toxicology Feb 2018Daily exposure to low doses of 3-methylcholanthrene (3MC) during the pubertal period in rats disrupts both follicular growth and ovulation. Thus, to provide new insights...
Daily exposure to low doses of 3-methylcholanthrene (3MC) during the pubertal period in rats disrupts both follicular growth and ovulation. Thus, to provide new insights into the toxicity mechanism of 3MC in the ovary, here we investigated the effect of daily exposure to 3MC on selected ovarian genes, the role of the aryl hydrocarbon receptor (AhR) and the level of epigenetic remodeling of histone post-transcriptional modifications. Immature rats were daily injected with 3MC (0.1 or 1 mg/kg) and mRNA expression of genes involved in different ovarian processes were evaluated. Of the 29 genes studied, 18 were up-regulated, five were down-regulated and six were not altered. To assess whether AhR was involved in these changes, we used the chromatin immunoprecipitation assay. 3MC increased AhR binding to promoter regions of genes involved in Notch signaling (Hes1, Jag1), activation of primordial follicles (Cdk2), cell adhesion (Icam1), stress and tumor progression (Dnajb6), apoptosis (Bax, Caspase-9) and expression of growth and transcription factors (Igf2, Sp1). Studying the trimethylation and acetylation of histone 3 (H3K4me3 and H3K9Ac, respectively) of these genes, we found that 3MC increased H3K4me3 in Cyp1a1, Jag1, Dnajb6, Igf2, Notch2, Adamts1, Bax and Caspase-9, and H3K9Ac in Cyp1a1, Jag1, Cdk2, Dnajb6, Igf2, Icam1, and Sp1. Co-treatment with α-naphthoflavone (αNF), a specific antagonist of AhR, prevented almost every 3MC-induced changes. Despite the low dose used in these experiments, daily exposure to 3MC induced changes in both gene expression and epigenomic remodeling, which may lead to premature ovarian failure.
Topics: Acetylation; Animals; Benzoflavones; Chromatin Immunoprecipitation; Down-Regulation; Epigenesis, Genetic; Female; Histones; Methylation; Methylcholanthrene; Ovarian Follicle; Promoter Regions, Genetic; Protein Binding; Protein Processing, Post-Translational; Rats; Rats, Sprague-Dawley; Receptors, Aryl Hydrocarbon; Up-Regulation
PubMed: 29094188
DOI: 10.1007/s00204-017-2096-5 -
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 -
International Journal of Molecular... Oct 2017Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor and its expression is influenced by environmental compounds, such as 3-methylcholanthrene...
Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor and its expression is influenced by environmental compounds, such as 3-methylcholanthrene (3-MC) and β-naphthoflavone (β-NF). AhR and its downstream genes, such as , are considered to play a pivotal role in xenobiotic responses. AhR signaling has also been proposed to mediate osteogenesis in experimental animals, but its details have remained unclear. Therefore, in this study, we examined the possible roles of AhR in human bone. Immunohistochemical analysis revealed that AhR was detected in both osteoblasts and osteoclasts. We then screened AhR-target genes using a microarray analysis in human osteoblastic hFOB cells. Results of microarray and subsequent PCR analysis did reveal that estrogen metabolizing and synthesizing enzymes, such as CYP1B1 and aromatase, were increased by 3-MC in hFOB and osteosarcoma cell line, MG-63. The subsequent antibody cytokine analysis also demonstrated that interleukin-1β and -6 expression was increased by 3-MC and β-NF in hFOB cells and these interleukins were well known to induce aromatase. We then examined the cell proliferation rate of hFOB and MG-63 cells co-treated with 3-MC and testosterone as an aromatase substrate. The status of cell proliferation in both hFOB and MG-63 cells was stimulated by 3-MC and testosterone treatment, which was also inhibited by an estrogen blocker, aromatase inhibitor, or AhR antagonist. These findings indicated that AhR could regulate estrogen synthesis and metabolism in bone tissues through cytokine/aromatase signaling.
Topics: Aromatase; Bone and Bones; Cell Line; Cell Line, Tumor; Cell Proliferation; Cytokines; Estrogens; Gene Expression; Gene Expression Regulation; Humans; Immunohistochemistry; Methylcholanthrene; Osteoblasts; Osteosarcoma; Receptors, Aryl Hydrocarbon; Signal Transduction
PubMed: 29039776
DOI: 10.3390/ijms18102159 -
Oncotarget Sep 2017Neoplastic cells live in a stressful context and survive thanks to their ability to overcome stress. Thus, tumor cell responses to stress are potential therapeutic...
Restoring microenvironmental redox and pH homeostasis inhibits neoplastic cell growth and migration: therapeutic efficacy of esomeprazole plus sulfasalazine on 3-MCA-induced sarcoma.
Neoplastic cells live in a stressful context and survive thanks to their ability to overcome stress. Thus, tumor cell responses to stress are potential therapeutic targets. We selected two such responses in melanoma and sarcoma cells: the xc- antioxidant system, that opposes oxidative stress, and surface v-ATPases that counteract the low pHi by extruding protons, and targeted them with the xc- blocker sulfasalazine and the proton pump inhibitor esomeprazole. Sulfasalazine inhibited the cystine/cysteine redox cycle and esomeprazole decreased pHi while increasing pHe in tumor cell lines. Although the single treatment with either drug slightly inhibited cell proliferation and motility, the association of sulfasalazine and esomeprazole powerfully decreased sarcoma and melanoma growth and migration. In the 3-methylcholanthrene (3-MCA)-induced sarcoma model, the combined therapy strongly reduced the tumor burden and increased the survival time: notably, 22 % of double-treated mice recovered and survived off therapy. Tumor-associated macrophages (TAM) displaying M2 markers, that abundantly infiltrate sarcoma and melanoma, overexpress xc- and membrane v-ATPases and were drastically decreased in tumors from mice undergone the combined therapy. Thus, the double targeting of tumor cells and macrophages by sulfasalazine and esomeprazole has a double therapeutic effect, as decreasing TAM infiltration deprives tumor cells of a crucial allied. Sulfasalazine and esomeprazole may therefore display unexpected therapeutic values, especially in case of hard-to-treat cancers.
PubMed: 28978047
DOI: 10.18632/oncotarget.18713 -
Cancer Immunology Research Nov 2017T-cell infiltration into tumors represents a critical bottleneck for immune-mediated control of cancer. We previously showed that this bottleneck can be overcome by...
T-cell infiltration into tumors represents a critical bottleneck for immune-mediated control of cancer. We previously showed that this bottleneck can be overcome by depleting immunosuppressive Foxp3 regulatory T cells (Tregs), a process that can increase frequencies of tumor-infiltrating lymphocytes through promoting the development of specialized portals for lymphocyte entry, namely high endothelial venules (HEVs). In this paper, we used a carcinogen-induced tumor model that allows for coevolution of the tumor microenvironment and the immune response to demonstrate that Treg depletion not only results in widespread disruption to HEV networks in lymph nodes (LNs) but also activates CD8 T cells, which then drive intratumoral HEV development. Formation of these vessels contrasts with ontogenic HEV development in LNs in that the process is dependent on the TNF receptor and independent of lymphotoxin β receptor-mediated signaling. These intratumoral HEVs do not express the chemokine CCL21, revealing a previously undescribed intratumoral blood vessel phenotype. We propose a model where Treg depletion enables a self-amplifying loop of T-cell activation, which promotes HEV development, T-cell infiltration, and ultimately, tumor destruction. The findings point to a need to test for HEV development as part of ongoing clinical studies in patients with cancer. .
Topics: Animals; Dendritic Cells; Endothelium, Vascular; Lymphocyte Depletion; Lymphocytes, Tumor-Infiltrating; Lymphotoxin beta Receptor; Methylcholanthrene; Mice; Neoplasms; Receptors, Tumor Necrosis Factor; T-Lymphocytes, Regulatory
PubMed: 28947544
DOI: 10.1158/2326-6066.CIR-17-0131 -
Nature Communications Sep 2017The analysis of neoantigen-specific CD8 T cells in tumour-bearing individuals is challenging due to the small pool of tumour antigen-specific T cells. Here we show that...
The analysis of neoantigen-specific CD8 T cells in tumour-bearing individuals is challenging due to the small pool of tumour antigen-specific T cells. Here we show that mass cytometry with multiplex combinatorial tetramer staining can identify and characterize neoantigen-specific CD8 T cells in mice bearing T3 methylcholanthrene-induced sarcomas that are susceptible to checkpoint blockade immunotherapy. Among 81 candidate antigens tested, we identify T cells restricted to two known neoantigens simultaneously in tumours, spleens and lymph nodes in tumour-bearing mice. High-dimensional phenotypic profiling reveals that antigen-specific, tumour-infiltrating T cells are highly heterogeneous. We further show that neoantigen-specific T cells display a different phenotypic profile in mice treated with anti-CTLA-4 or anti-PD-1 immunotherapy, whereas their peripheral counterparts are not affected by the treatments. Our results provide insights into the nature of neoantigen-specific T cells and the effects of checkpoint blockade immunotherapy.Immune checkpoint blockade (ICB) therapies can unleash anti-tumour T-cell responses. Here the authors show, by integrating MHC tetramer multiplexing, mass cytometry and high-dimensional analyses, that neoantigen-specific, tumour-infiltrating T cells are highly heterogeneous and are subjected to ICB modulations.
Topics: Animals; Antigens, Neoplasm; Antineoplastic Agents, Immunological; CD8-Positive T-Lymphocytes; CTLA-4 Antigen; Immunophenotyping; Immunotherapy; Lymphocytes, Tumor-Infiltrating; Methylcholanthrene; Mice; Programmed Cell Death 1 Receptor; Sarcoma, Experimental
PubMed: 28916749
DOI: 10.1038/s41467-017-00627-z