1
|
Suzuki K, Imaoka T, Tomita M, Sasatani M, Doi K, Tanaka S, Kai M, Yamada Y, Kakinuma S. Molecular and cellular basis of the dose-rate-dependent adverse effects of radiation exposure in animal models. Part I: Mammary gland and digestive tract. JOURNAL OF RADIATION RESEARCH 2023; 64:210-227. [PMID: 36773323 PMCID: PMC10036108 DOI: 10.1093/jrr/rrad002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 10/04/2022] [Indexed: 06/18/2023]
Abstract
While epidemiological data are available for the dose and dose-rate effectiveness factor (DDREF) for human populations, animal models have contributed significantly to providing quantitative data with mechanistic insights. The aim of the current review is to compile both the in vitro experiments with reference to the dose-rate effects of DNA damage and repair, and the animal studies, specific to rodents, with reference to the dose-rate effects of cancer development. In particular, the review focuses especially on the results pertaining to underlying biological mechanisms and discusses their possible involvement in the process of radiation-induced carcinogenesis. Because the concept of adverse outcome pathway (AOP) together with the key events has been considered as a clue to estimate radiation risks at low doses and low dose-rates, the review scrutinized the dose-rate dependency of the key events related to carcinogenesis, which enables us to unify the underlying critical mechanisms to establish a connection between animal experimental studies with human epidemiological studies.
Collapse
Affiliation(s)
- Keiji Suzuki
- Corresponding author. Department of Radiation Medical Sciences, Nagasaki University Atomic Bomb Disease Institute. 1-12-4 Sakamoto, Nagasaki 852-8523, Japan. Tel: +81-95-819-7116; Fax: +81-95-819-7117;
| | | | | | | | - Kazutaka Doi
- Department of Radiation Regulatory Science Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Satoshi Tanaka
- Department of Radiobiology, Institute for Environmental Sciences, 1-7 Ienomae, Obuchi, Rokkasho-mura, Kamikita-gun, Aomori 039-3212, Japan
| | - Michiaki Kai
- Nippon Bunri University, 1727-162 Ichiki, Oita, Oita 870-0397, Japan
| | - Yutaka Yamada
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Shizuko Kakinuma
- Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| |
Collapse
|
2
|
Yamana K, Inoue J, Yoshida R, Sakata J, Nakashima H, Arita H, Kawaguchi S, Gohara S, Nagao Y, Takeshita H, Maeshiro M, Liu R, Matsuoka Y, Hirayama M, Kawahara K, Nagata M, Hirosue A, Toya R, Murakami R, Kuwahara Y, Fukumoto M, Nakayama H. Extracellular vesicles derived from radioresistant oral squamous cell carcinoma cells contribute to the acquisition of radioresistance via the miR-503-3p-BAK axis. J Extracell Vesicles 2021; 10:e12169. [PMID: 34894384 PMCID: PMC8665688 DOI: 10.1002/jev2.12169] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 11/02/2021] [Accepted: 11/08/2021] [Indexed: 12/15/2022] Open
Abstract
Despite advancements in treatments, oral squamous cell carcinoma (OSCC) has not significantly improved in prognosis or survival rate primarily due to the presence of treatment-resistant OSCC. The intercellular communication between tumour cells is a molecular mechanism involved in acquiring OSCC treatment resistance. Extracellular vesicles (EVs) and encapsulated miRNAs are important mediators of intercellular communication. Here, we focused on EVs released from clinically relevant radioresistant (CRR) OSCC cells. Additionally, we evaluated the correlation between miRNA expression in the serum samples of patients who showed resistance to radiotherapy and in EVs released from CRR OSCC cells. We found that EVs released from CRR OSCC cells conferred radioresistance to radiosensitive OSCC cells via miR-503-3p contained in EVs. This miR-503-3p inhibited BAK and impaired the caspase cascade to suppress radiation-induced apoptosis. Furthermore, OSCC cells with BAK knockdown had increased radioresistance. Additionally, the expression of circulating miR-503-3p in patients with OSCC was correlated with a poor treatment response and prognosis of radiotherapy. Our results provide new insights into the relationship between EVs and the radioresistance of OSCC and suggest that the miR-503-3p-BAK axis may be a therapeutic target and that circulating miR-503-3p is a useful prognostic biomarker in the radiotherapy of OSCC.
Collapse
Affiliation(s)
- Keisuke Yamana
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Junki Inoue
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Ryoji Yoshida
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Junki Sakata
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Hikaru Nakashima
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Hidetaka Arita
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Sho Kawaguchi
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Shunsuke Gohara
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Yuka Nagao
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Hisashi Takeshita
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Manabu Maeshiro
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Rin Liu
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Yuichiro Matsuoka
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Masatoshi Hirayama
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Kenta Kawahara
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Masashi Nagata
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Akiyuki Hirosue
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Ryo Toya
- Department of Radiation OncologyKumamoto University Hospital, Kumamoto, Japan
| | - Ryuji Murakami
- Department of Medical Imaging, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| | - Yoshikazu Kuwahara
- Radiation Biology and Medicine, Faculty of MedicineTohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Manabu Fukumoto
- Department of Molecular PathologyTokyo Medical University, Tokyo, Japan
| | - Hideki Nakayama
- Department of Oral and Maxillofacial Surgery, Faculty of Life SciencesKumamoto University, Kumamoto, Japan
| |
Collapse
|
3
|
Mast1 mediates radiation-induced gastric injury via the P38 MAPK pathway. Exp Cell Res 2021; 409:112913. [PMID: 34774870 DOI: 10.1016/j.yexcr.2021.112913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 11/20/2022]
Abstract
Radiation-induced gastric injury is a serious adverse effect and reduces the efficacy of radiotherapy treatment. However, the mechanisms underlying radiation-induced stomach injury remain unclear. Here, mouse stomach and gastric epithelial cells were irradiated with different doses of X-ray radiation. The results showed that radiation induced gastric injury in vivo and in vitro. Differentially expressed functional mRNAs in irradiation-induced gastric tissues were screened from the Gene Expression Omnibus (GEO) database. We found that the expression of microtubule-associated serine/threonine kinase 1 (Mast1) was downregulated in mouse gastric tissues and gastric epithelial cells after irradiation. Furthermore, functional assays showed that knockdown of Mast1 inhibited growth and promoted apoptosis in gastric epithelial cells, while overexpression of Mast1 protected gastric epithelial cells from radiation damage. Mechanistically, Mast1 negatively regulated radiation-induced injury in gastric epithelial cells by inhibiting the activation of P38. The apoptosis caused by knockdown of Mast1 in gastric epithelial cells could be partially reversed by the P38 inhibitor SB203580. Moreover, data from several gastric cancer cell lines and online databases revealed that Mast1 was not involved in the development of gastric cancer. Collectively, our findings demonstrated that Mast1 is essential for radiation-induced gastric injury, providing a promising prognostic and therapeutic target.
Collapse
|
4
|
Lv H, Lin Y, Liu P, Liang W, Wei K, Pu J, Zhang H. Protective effects and potential underlying mechanisms of sodium copper chlorophyllin against ethanol-induced gastric ulcer in mice. Acta Biochim Biophys Sin (Shanghai) 2019; 51:925-933. [PMID: 31435637 DOI: 10.1093/abbs/gmz083] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Indexed: 12/12/2022] Open
Abstract
In study, we aimed to determine the mechanisms underlying the gastroprotective effects of sodium copper chlorophyllin (SCC) against ethanol-induced gastric ulcer injury in mice. First, the gastroprotective effects of SCC against gastric ulcer induced by ethanol were assessed. Then, biochemical, histopathological, immunohistochemistry assays, and western blot analysis were conducted to determine the possible mechanisms of action underlying the effects of SCC. Compared to the effects of omeprazole (OME) in a confirmed mouse model of ethanol-induced gastric ulcer injury, treatment with various doses of SCC resulted in up-regulation of Bcl-2 and down-regulation of the pro-apoptotic protein Bax. Significant decreases in the levels of the malondialdehyde (MDA), myeloperoxidase (MPO), and NO in the gastric tissues were observed. Furthermore, inflammatory cytokine analysis revealed that SCC treatment inhibited the expressions of TNF-α and IL-6, greatly reduced the phosphorylation level of IκB, and repressed the nuclear translocation of NF-κB p65, which demonstrated that SCC inhibited the activation of the NF-κB pathway. The present findings suggest that the protective effects of SCC may be beneficial as a potential preventive and therapeutic agent for gastric ulcer through the NF-κB pathway. Taken together, SCC administration significantly decreased the levels of MPO, NO, and MDA in gastric tissue and exerted a powerful anti-inflammatory activity as demonstrated by reduction in the secretions of proinflammatory mediators such as IL-6 and TNF-α in the serum of mice exposed to ethanol.
Collapse
Affiliation(s)
- Huawei Lv
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yan Lin
- Department of Pharmacy, Tongde Hospital of Zhejiang Province, Hangzhou 310012, China
| | - Peigang Liu
- Center for Medicinal Resources Research, Key Laboratory of Research and Development of Chinese Medicine of Zhejiang Province, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou 310007, China
| | - Weiqing Liang
- Center for Medicinal Resources Research, Key Laboratory of Research and Development of Chinese Medicine of Zhejiang Province, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou 310007, China
| | - Kemin Wei
- Center for Medicinal Resources Research, Key Laboratory of Research and Development of Chinese Medicine of Zhejiang Province, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou 310007, China
| | - Jinbao Pu
- Center for Medicinal Resources Research, Key Laboratory of Research and Development of Chinese Medicine of Zhejiang Province, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou 310007, China
| | - Hongjian Zhang
- Center for Medicinal Resources Research, Key Laboratory of Research and Development of Chinese Medicine of Zhejiang Province, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou 310007, China
| |
Collapse
|
5
|
Cao X, Wen P, Fu Y, Gao Y, Qi X, Chen B, Tao Y, Wu L, Xu A, Lu H, Zhao G. Radiation induces apoptosis primarily through the intrinsic pathway in mammalian cells. Cell Signal 2019; 62:109337. [PMID: 31173879 DOI: 10.1016/j.cellsig.2019.06.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 06/03/2019] [Accepted: 06/03/2019] [Indexed: 12/13/2022]
Abstract
Radiation-induced tumor cells death is the theoretical basis of tumor radiotherapy. Death signaling disorder is the most important factor for radioresistance. However, the signaling pathway(s) leading to radiation-triggered cell death is (are) still not completely known. To better understand the cell death signaling induced by radiation, the immortalized mouse embryonic fibroblast (MEF) deficient in "initiator" caspases, "effector" caspases or different Bcl-2 family proteins together with human colon carcinoma cell HCT116 were used. Our data indicated that radiation selectively induced the activation of caspase-9 and caspase-3/7 but not caspase-8 by triggering mitochondrial outer membrane permeabilization (MOMP). Importantly, the role of radiation in MOMP is independent of the activation of both "initiator" and "effector" caspases. Furthermore, both proapoptotic and antiapoptotic Bcl-2 family proteins were involved in radiation-induced apoptotic signaling. Overall, our study indicated that radiation specifically triggered the intrinsic apoptotic signaling pathway through Bcl-2 family protein-dependent mitochondrial permeabilization, which indicates targeting mitochondria is a promising strategy for cancer radiotherapy.
Collapse
Affiliation(s)
- Xianbin Cao
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei, PR China; University of Science and Technology of China, Hefei, PR China
| | - Pengbo Wen
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei, PR China; University of Science and Technology of China, Hefei, PR China
| | - Yanfang Fu
- School of Natural Resources and Environment, Chizhou University, Chizhou, Anhui 247000, PR China
| | - Yang Gao
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei, PR China; University of Science and Technology of China, Hefei, PR China
| | - Xiaojing Qi
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei, PR China; University of Science and Technology of China, Hefei, PR China
| | - Bin Chen
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei, PR China; University of Science and Technology of China, Hefei, PR China
| | - Yinping Tao
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei, PR China; University of Science and Technology of China, Hefei, PR China
| | - Lijun Wu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei, PR China
| | - An Xu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei, PR China
| | - Huayi Lu
- Second Hospital, Jilin University, Changchun, PR China.
| | - Guoping Zhao
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei, PR China.
| |
Collapse
|
6
|
Burkitt MD, Williams JM, Townsend T, Hough R, Duckworth CA, Pritchard DM. Mice lacking NF-κB1 exhibit marked DNA damage responses and more severe gastric pathology in response to intraperitoneal tamoxifen administration. Cell Death Dis 2017; 8:e2939. [PMID: 28726772 PMCID: PMC5584614 DOI: 10.1038/cddis.2017.332] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 06/14/2017] [Accepted: 06/15/2017] [Indexed: 01/15/2023]
Abstract
Tamoxifen (TAM) has recently been shown to cause acute gastric atrophy and metaplasia in mice. We have previously demonstrated that the outcome of Helicobacter felis infection, which induces similar gastric lesions in mice, is altered by deletion of specific NF-κB subunits. Nfkb1-/- mice developed more severe gastric atrophy than wild-type (WT) mice 6 weeks after H. felis infection. In contrast, Nfkb2-/- mice were protected from this pathology. We therefore hypothesized that gastric lesions induced by TAM may be similarly regulated by signaling via NF-κB subunits. Groups of five female C57BL/6 (WT), Nfkb1-/-, Nfkb2-/- and c-Rel-/- mice were administered 150 mg/kg TAM by IP injection. Seventy-two hours later, gastric corpus tissues were taken for quantitative histological assessment. In addition, groups of six female WT and Nfkb1-/- mice were exposed to 12 Gy γ-irradiation. Gastric epithelial apoptosis was quantified 6 and 48 h after irradiation. TAM induced gastric epithelial lesions in all strains of mice, but this was more severe in Nfkb1-/- mice than in WT mice. Nfkb1-/- mice exhibited more severe parietal cell loss than WT mice, had increased gastric epithelial expression of Ki67 and had an exaggerated gastric epithelial DNA damage response as quantified by γH2AX. To investigate whether the difference in gastric epithelial DNA damage response of Nfkb1-/- mice was unique to TAM-induced DNA damage or a generic consequence of DNA damage, we also assessed gastric epithelial apoptosis following γ-irradiation. Six hours after γ-irradiation, gastric epithelial apoptosis was increased in the gastric corpus and antrum of Nfkb1-/- mice. NF-κB1-mediated signaling regulates the development of gastric mucosal pathology following TAM administration. This is associated with an exaggerated gastric epithelial DNA damage response. This aberrant response appears to reflect a more generic sensitization of the gastric mucosa of Nfkb1-/- mice to DNA damage.
Collapse
Affiliation(s)
- Michael D Burkitt
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, The Henry Wellcome Laboratory, Liverpool, UK
| | | | - Tristan Townsend
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, The Henry Wellcome Laboratory, Liverpool, UK
| | - Rachael Hough
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, The Henry Wellcome Laboratory, Liverpool, UK
| | | | - D Mark Pritchard
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, The Henry Wellcome Laboratory, Liverpool, UK
| |
Collapse
|
7
|
Niwa O, Barcellos-Hoff MH, Globus RK, Harrison JD, Hendry JH, Jacob P, Martin MT, Seed TM, Shay JW, Story MD, Suzuki K, Yamashita S. ICRP Publication 131: Stem Cell Biology with Respect to Carcinogenesis Aspects of Radiological Protection. Ann ICRP 2016; 44:7-357. [PMID: 26637346 DOI: 10.1177/0146645315595585] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This report provides a review of stem cells/progenitor cells and their responses to ionising radiation in relation to issues relevant to stochastic effects of radiation that form a major part of the International Commission on Radiological Protection's system of radiological protection. Current information on stem cell characteristics, maintenance and renewal, evolution with age, location in stem cell 'niches', and radiosensitivity to acute and protracted exposures is presented in a series of substantial reviews as annexes concerning haematopoietic tissue, mammary gland, thyroid, digestive tract, lung, skin, and bone. This foundation of knowledge of stem cells is used in the main text of the report to provide a biological insight into issues such as the linear-no-threshold (LNT) model, cancer risk among tissues, dose-rate effects, and changes in the risk of radiation carcinogenesis by age at exposure and attained age. Knowledge of the biology and associated radiation biology of stem cells and progenitor cells is more developed in tissues that renew fairly rapidly, such as haematopoietic tissue, intestinal mucosa, and epidermis, although all the tissues considered here possess stem cell populations. Important features of stem cell maintenance, renewal, and response are the microenvironmental signals operating in the niche residence, for which a well-defined spatial location has been identified in some tissues. The identity of the target cell for carcinogenesis continues to point to the more primitive stem cell population that is mostly quiescent, and hence able to accumulate the protracted sequence of mutations necessary to result in malignancy. In addition, there is some potential for daughter progenitor cells to be target cells in particular cases, such as in haematopoietic tissue and in skin. Several biological processes could contribute to protecting stem cells from mutation accumulation: (a) accurate DNA repair; (b) rapidly induced death of injured stem cells; (c) retention of the DNA parental template strand during divisions in some tissue systems, so that mutations are passed to the daughter differentiating cells and not retained in the parental cell; and (d) stem cell competition, whereby undamaged stem cells outcompete damaged stem cells for residence in the niche. DNA repair mainly occurs within a few days of irradiation, while stem cell competition requires weeks or many months depending on the tissue type. The aforementioned processes may contribute to the differences in carcinogenic radiation risk values between tissues, and may help to explain why a rapidly replicating tissue such as small intestine is less prone to such risk. The processes also provide a mechanistic insight relevant to the LNT model, and the relative and absolute risk models. The radiobiological knowledge also provides a scientific insight into discussions of the dose and dose-rate effectiveness factor currently used in radiological protection guidelines. In addition, the biological information contributes potential reasons for the age-dependent sensitivity to radiation carcinogenesis, including the effects of in-utero exposure.
Collapse
|
8
|
Duckworth CA, Abuderman AA, Burkitt MD, Williams JM, O'Reilly LA, Pritchard DM. bak deletion stimulates gastric epithelial proliferation and enhances Helicobacter felis-induced gastric atrophy and dysplasia in mice. Am J Physiol Gastrointest Liver Physiol 2015; 309:G420-30. [PMID: 26159699 PMCID: PMC4572407 DOI: 10.1152/ajpgi.00404.2014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 07/01/2015] [Indexed: 01/31/2023]
Abstract
Helicobacter infection causes a chronic superficial gastritis that in some cases progresses via atrophic gastritis to adenocarcinoma. Proapoptotic bak has been shown to regulate radiation-induced apoptosis in the stomach and colon and also susceptibility to colorectal carcinogenesis in vivo. Therefore we investigated the gastric mucosal pathology following H. felis infection in bak-null mice at 6 or 48 wk postinfection. Primary gastric gland culture from bak-null mice was also used to assess the effects of bak deletion on IFN-γ-, TNF-α-, or IL-1β-induced apoptosis. bak-null gastric corpus glands were longer, had increased epithelial Ki-67 expression, and contained fewer parietal and enteroendocrine cells compared with the wild type (wt). In wt mice, bak was expressed at the luminal surface of gastric corpus glands, and this increased 2 wk post-H. felis infection. Apoptotic cell numbers were decreased in bak-null corpus 6 and 48 wk following infection and in primary gland cultures following cytokine administration. Increased gastric epithelial Ki-67 labeling index was observed in C57BL/6 mice after H. felis infection, whereas no such increase was detected in bak-null mice. More severe gastric atrophy was observed in bak-null compared with C57BL/6 mice 6 and 48 wk postinfection, and 76% of bak-null compared with 25% of C57BL/6 mice showed evidence of gastric dysplasia following long-term infection. Collectively, bak therefore regulates gastric epithelial cell apoptosis, proliferation, differentiation, mucosal thickness, and susceptibility to gastric atrophy and dysplasia following H. felis infection.
Collapse
Affiliation(s)
- C. A. Duckworth
- 1Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom;
| | - A. A. Abuderman
- 1Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom;
| | - M. D. Burkitt
- 1Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom;
| | - J. M. Williams
- 1Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom;
| | - L. A. O'Reilly
- 2The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia; and ,3Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - D. M. Pritchard
- 1Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom;
| |
Collapse
|
9
|
Zhao DY, Jacobs KM, Hallahan DE, Thotala D. Silencing Egr1 Attenuates Radiation-Induced Apoptosis in Normal Tissues while Killing Cancer Cells and Delaying Tumor Growth. Mol Cancer Ther 2015. [PMID: 26206332 DOI: 10.1158/1535-7163.mct-14-1051] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Normal tissue toxicity reduces the therapeutic index of radiotherapy and decreases the quality of life for cancer survivors. Apoptosis is a key element of the radiation response in normal tissues like the hippocampus and small intestine, resulting in neurocognitive disorders and intestinal malabsorption. The Early Growth Response 1 (Egr1) transcription factor mediates radiation-induced apoptosis by activating the transcription of proapoptosis genes in response to ionizing radiation (IR). Therefore, we hypothesized that the genetic abrogation of Egr1 and the pharmacologic inhibition of its transcriptional activity could attenuate radiation-induced apoptosis in normal tissues. We demonstrated that Egr1-null mice had less apoptosis in the hippocampus and intestine following irradiation as compared with their wild-type littermates. A similar result was achieved using Mithramycin A (MMA) to prevent binding of Egr1 to target promoters in the mouse intestine. Abolishing Egr1 expression using shRNA dampened apoptosis and enhanced the clonogenic survival of irradiated HT22 hippocampal neuronal cells and IEC6 intestinal epithelial cells. Mechanistically, these events involved an abrogation of p53 induction by IR and an increase in the ratio of Bcl-2/Bax expression. In contrast, targeted silencing of Egr1 in two cancer cell lines (GL261 glioma cells and HCT116 colorectal cancer cells) was not radioprotective, since it reduced their growth while also sensitizing them to radiation-induced death. Further, Egr1 depletion delayed the growth of heterotopically implanted GL261 and HCT116 tumors. These results support the potential of silencing Egr1 in order to minimize the normal tissue complications associated with radiotherapy while enhancing tumor control.
Collapse
Affiliation(s)
- Diana Yi Zhao
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, Missouri
| | - Keith M Jacobs
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, Missouri
| | - Dennis E Hallahan
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, Missouri. Siteman Cancer Center, Washington University School of Medicine in St. Louis, St. Louis, Missouri. Mallinckrodt Institute of Radiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri
| | - Dinesh Thotala
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, Missouri. Siteman Cancer Center, Washington University School of Medicine in St. Louis, St. Louis, Missouri.
| |
Collapse
|
10
|
Bing SJ, Kim MJ, Ahn G, Im J, Kim DS, Ha D, Cho J, Kim A, Jee Y. Acidic polysaccharide of Panax ginseng regulates the mitochondria/caspase-dependent apoptotic pathway in radiation-induced damage to the jejunum in mice. Acta Histochem 2014; 116:514-21. [PMID: 24380494 DOI: 10.1016/j.acthis.2013.11.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 11/01/2013] [Accepted: 11/06/2013] [Indexed: 12/17/2022]
Abstract
Owing to its susceptibility to radiation, the small intestine of mice is valuable for studying radioprotective effects. When exposed to radiation, intestinal crypt cells immediately go through apoptosis, which impairs swift differentiation necessary for the regeneration of intestinal villi. Our previous studies have elucidated that acidic polysaccharide of Panax ginseng (APG) protects the mouse small intestine from radiation-induced damage by lengthening villi with proliferation and repopulation of crypt cells. In the present study, we identified the molecular mechanism involved. C57BL/6 mice were irradiated with gamma-rays with or without APG and the expression levels of apoptosis-related molecules in the jejunum were investigated using immunohistochemistry. APG pretreatment strongly decreased the radiation-induced apoptosis in the jejunum. It increased the expression levels of anti-apoptotic proteins (Bcl-2 and Bcl-XS/L) and dramatically reduced the expression levels of pro-apoptotic proteins (p53, BAX, cytochrome c and caspase-3). Therefore, APG attenuated the apoptosis through the intrinsic pathway, which is controlled by p53 and Bcl-2 family members. Results presented in this study suggest that APG protects the mouse small intestine from irradiation-induced apoptosis through inhibition of the p53-dependent pathway and the mitochondria/caspase pathway. Thus, APG may be a potential agent for preventing radiation induced injuries in intestinal cells during radio-therapy such as in cancer treatment.
Collapse
|
11
|
Zhang C, Ni J, Li BL, Gao F, Liu H, Liu W, Huang YJ, Cai JM. CpG-Oligodeoxynucleotide Treatment Protects against Ionizing Radiation-Induced Intestine Injury. PLoS One 2013; 8:e66586. [PMID: 23805241 PMCID: PMC3689777 DOI: 10.1371/journal.pone.0066586] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Accepted: 05/08/2013] [Indexed: 11/18/2022] Open
Abstract
Background the bone marrow and the intestine are the major sites of ionizing radiation (IR)-induced injury. Our previous study demonstrated that CpG-oligodeoxynucleotide (ODN) treatment mitigated IR-induced bone marrow injury, but its effect on the intestine is not known. In this study, we sought to determine if CpG-ODN have protective effect on IR-induced intestine injury, and if so, to determine the mechanism of its effect. Methods and Findings Mice were treated with CpG-ODN after IR. The body weight and survival were daily monitored for 30 days consecutively after exposure. The number of surviving intestinal crypt was assessed by the microcolony survival assay. The number and the distribution of proliferating cell in crypt were evaluated by TUNEL assay and BrdU assay. The expression of Bcl-2, Bax and caspase-3 in crypt were analyzed by Immunohistochemistry assay. The findings showed that the treatment for irradiated mice with CpG-ODN diminished body weight loss, improved 30 days survival, enhanced intestinal crypts survival and maintained proliferating cell population and regeneration in crypt. The reason might involve that CpG-ODN up-regulated the expression of Bcl-2 protein and down-regulated the expression of Bax protein and caspase-3 protein. Conclusion CpG-ODN was effective in protection of IR-induced intestine injury by enhancing intestinal crypts survival and maintaining proliferating cell population and regeneration in crypt. The mechanism might be that CpG-ODN inhibits proliferating cell apoptosis through regulating the expression of apoptosis-related protein, such as Bax, Bcl-2 and caspase-3.
Collapse
Affiliation(s)
- Chao Zhang
- Section of Radiation Medicine, Department of Naval medicine, Second Military Medical University, Shanghai, China
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Abstract
FUS1/TUSC2 is a mitochondrial tumor suppressor with activity to regulate cellular oxidative stress by maintaining balanced ROS production and mitochondrial homeostasis. Fus1 expression is inhibited by ROS, suggesting that individuals with a high level of ROS may have lower Fus1 in normal tissues and, thus, may be more prone to oxidative stress-induced side effects of cancer treatment, including radiotherapy. As the role of Fus1 in the modulation of cellular radiosensitivity is unknown, we set out to determine molecular mechanisms of Fus1 involvement in the IR response in normal tissues. Mouse whole-body irradiation methodology was employed to determine the role for Fus1 in the radiation response and explore underlying molecular mechanisms. Fus1(-/-) mice were more susceptible to radiation compared with Fus1(+/+) mice, exhibiting increased mortality and accelerated apoptosis of the GI crypt epithelial cells. Following untimely reentrance into the cell cycle, the Fus1(-/-) GI crypt cells died at accelerated rate via mitotic catastrophe that resulted in diminished and/or delayed crypt regeneration after irradiation. At the molecular level, dysregulated dynamics of activation of main IR response proteins (p53, NFκB, and GSK-3β), as well as key signaling pathways involved in oxidative stress response (SOD2, PRDX1, and cytochrome c), apoptosis (BAX and PARP1), cell cycle (Cyclins B1 and D1), and DNA repair (γH2AX) were found in Fus1(-/-) cells after irradiation. Increased radiosensitivity of other tissues, such as immune cells and hair follicles was also detected in Fus1(-/-) mice. Our findings demonstrate a previously unknown radioprotective function of the mitochondrial tumor suppressor Fus1 in normal tissues and suggest new individualized therapeutic approaches based on Fus1 expression.
Collapse
|
13
|
Radulescu S, Ridgway RA, Cordero J, Athineos D, Salgueiro P, Poulsom R, Neumann J, Jung A, Patel S, Woodgett J, Barker N, Pritchard DM, Oien K, Sansom OJ. Acute WNT signalling activation perturbs differentiation within the adult stomach and rapidly leads to tumour formation. Oncogene 2013; 32:2048-57. [PMID: 22665058 PMCID: PMC3631308 DOI: 10.1038/onc.2012.224] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 04/13/2012] [Accepted: 04/22/2012] [Indexed: 02/08/2023]
Abstract
A role for WNT signalling in gastric carcinogenesis has been suggested due to two major observations. First, patients with germline mutations in adenomatous polyposis coli (APC) are susceptible to stomach polyps and second, in gastric cancer, WNT activation confers a poor prognosis. However, the functional significance of deregulated WNT signalling in gastric homoeostasis and cancer is still unclear. In this study we have addressed this by investigating the immediate effects of WNT signalling activation within the stomach epithelium. We have specifically activated the WNT signalling pathway within the mouse adult gastric epithelium via deletion of either glycogen synthase kinase 3 (GSK3) or APC or via expression of a constitutively active β-catenin protein. WNT pathway deregulation dramatically affects stomach homoeostasis at very short latencies. In the corpus, there is rapid loss of parietal cells with fundic gland polyp (FGP) formation and adenomatous change, which are similar to those observed in familial adenomatous polyposis. In the antrum, adenomas occur from 4 days post-WNT activation. Taken together, these data show a pivotal role for WNT signalling in gastric homoeostasis, FGP formation and adenomagenesis. Loss of the parietal cell population and corresponding FGP formation, an early event in gastric carcinogenesis, as well as antral adenoma formation are immediate effects of nuclear β-catenin translocation and WNT target gene expression. Furthermore, our inducible murine model will permit a better understanding of the molecular changes required to drive tumourigenesis in the stomach.
Collapse
Affiliation(s)
- S Radulescu
- CR-UK Beatson Institute of Cancer Research, Glasgow, UK
| | - R A Ridgway
- CR-UK Beatson Institute of Cancer Research, Glasgow, UK
| | - J Cordero
- CR-UK Beatson Institute of Cancer Research, Glasgow, UK
| | - D Athineos
- CR-UK Beatson Institute of Cancer Research, Glasgow, UK
| | - P Salgueiro
- CR-UK Beatson Institute of Cancer Research, Glasgow, UK
- Institute of Medical Biology, A*STAR, 8A Biomedical Grove, Immunos, Singapore
| | - R Poulsom
- Histopathology Lab, CR-UK London Research Institute, London, UK
| | - J Neumann
- Pathologisches Institut, Ludwig-Maximilians Universität München, München, Germany
| | - A Jung
- Pathologisches Institut, Ludwig-Maximilians Universität München, München, Germany
| | - S Patel
- Samuel Lunenfeld Research Institute, Toronto, ON, Canada
| | - J Woodgett
- Samuel Lunenfeld Research Institute, Toronto, ON, Canada
| | - N Barker
- Institute of Medical Biology, A*STAR, 8A Biomedical Grove, Immunos, Singapore
| | - D M Pritchard
- Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - K Oien
- Institute of Cancer Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - O J Sansom
- CR-UK Beatson Institute of Cancer Research, Glasgow, UK
| |
Collapse
|
14
|
Duckworth CA, Clyde D, Pritchard DM. CD24 is expressed in gastric parietal cells and regulates apoptosis and the response to Helicobacter felis infection in the murine stomach. Am J Physiol Gastrointest Liver Physiol 2012; 303:G915-26. [PMID: 22899822 DOI: 10.1152/ajpgi.00068.2012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
CD24 is expressed in the putative stem cells within several tissues and is overexpressed in gastric and colonic adenocarcinomas. Perturbed CD24 expression may therefore alter the response of gastrointestinal epithelia to damage-inducing stimuli that induce cancer. We have investigated the effects of CD24 deletion on gastric responses to Helicobacter felis infection and γ-irradiation using CD24-null mice. Gastric CD24 expression was determined by immunohistochemistry in C57BL/6 mice. Female CD24-null and C57BL/6 mice were infected with H. felis for 6 wk, and inflammation, proliferation, apoptosis, and parietal cell numbers were assessed in gastric tissue sections. Apoptosis and proliferation were analyzed on a cell-positional basis in stomach, small intestine, and colon of CD24-null and C57BL/6 mice following γ-irradiation. Apoptosis was also assessed in HT29 cells following CD24 siRNA transfection. Of CD24-positive cells in the gastric corpus, 98% were H(+)-K(+)-ATPase-expressing parietal cells. CD24-null mice showed more prominent gastric H. felis colonization than C57BL/6 mice but displayed a marked reduction in corpus inflammation, reduced Ki67 labeling, and less gastric atrophy 6 wk following infection. Corpus apoptosis was elevated in CD24-null mice, but this did not increase further with H. felis infection as observed in C57BL/6 mice. More apoptotic cells were found following γ-irradiation in the stomach, small intestine, and colon of CD24-null mice and following CD24 knockdown in vitro. In conclusion, CD24 is expressed in gastric parietal cells, where it modulates gastric responses to H. felis and γ-radiation. CD24 also regulates susceptibility to apoptosis in the distal murine gastrointestinal tract.
Collapse
Affiliation(s)
- C A Duckworth
- Department of Gastroenterology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3GE, United Kingdom
| | | | | |
Collapse
|
15
|
Tong Q, Zhang W, Jin S, Li S, Chen Z. The relationship between p27(kip1) expression and the change of radiosensitivity of esophageal carcinoma cells. Scand J Gastroenterol 2011; 46:173-6. [PMID: 20923380 DOI: 10.3109/00365521.2010.522721] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Radioresistance is considered the main reason for therapeutic failure in radiotherapy of esophageal carcinoma. However, the underlying mechanisms of radioresistance remain elusive. The purpose of this study was to investigate the relationship between p27(kip1) expression and the change of radiosensitivity of esophageal carcinoma cells. MATERIAL AND METHODS Radioresistant cells were gradually isolated by means of repeated gamma-ray irradiation upon esophageal carcinoma cells. The radiosensitivity of established radioresistant cells and parental cells was measured by standard colony-forming assay. Cell cycle was detected by flow cytometry. Western blot method was performed to identify the expression of p27(kip1). RESULTS Colony-forming assay showed that the radioresistant cells had obvious radioresistance. Percentage of the radioresistant cells at G(0)/G(1) and G(2)/M phase was significantly decreased, and the percentage of S phase cells was significantly increased compared with the parent cells (p < 0.05). Western blotting revealed that p27(kip1) expression of the radioresistant cells was lower than that of parent cells. CONCLUSIONS Our results suggest that cell phase change due to the decrease of p27(kip1) expression is one of the mechanisms of radioresistance in esophageal carcinoma cells.
Collapse
Affiliation(s)
- Qiang Tong
- Department of Gastroenterology, Taihe Hospital, Hubei Medical University, Shiyan, Hubei, PR China.
| | | | | | | | | |
Collapse
|
16
|
Shibata W, Takaishi S, Muthupalani S, Pritchard DM, Whary MT, Rogers AB, Fox JG, Betz KS, Kaestner KH, Karin M, Wang TC. Conditional deletion of IkappaB-kinase-beta accelerates helicobacter-dependent gastric apoptosis, proliferation, and preneoplasia. Gastroenterology 2010; 138:1022-34.e1-10. [PMID: 19962981 PMCID: PMC2831162 DOI: 10.1053/j.gastro.2009.11.054] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Revised: 11/23/2009] [Accepted: 11/25/2009] [Indexed: 12/17/2022]
Abstract
BACKGROUND & AIMS The nuclear factor kappaB (NF-kappaB)/IkappaB-kinase-beta (IKKbeta) pathway has been shown to represent a key link between inflammation and cancer, inducing pro-inflammatory cytokines in myeloid cells and anti-apoptotic pathways in epithelial cells. However, the role of NF-kappaB pathway in gastric carcinogenesis and injury has not been well-defined. We derived mice with a conditional knockout of IKKbeta in gastric epithelial cells (GECs) and myeloid cells, and examined responses to ionizing radiation (IR) and Helicobacter felis infection. METHODS Ikkbeta(Deltastom) mice were generated by crossing Foxa3-Cre mice to Ikkbeta(F/F) mice. Cellular stress was induced with IR and H felis in Ikkbeta(Deltastom), Ikkbeta(F/F), and cis-NF-kappaB-enhanced green fluorescent protein (GFP) reporter mice. Gastric histopathology, apoptosis, proliferation, necrosis, reactive oxygen species, and expression of cytokines, chemokines, and anti-apoptotic genes were assessed. The role of myeloid IKKbeta in these models was studied by crosses with LysM-Cre mice. RESULTS NF-kappaB activity was upregulated in myeloid cells with acute H felis infection, but in GECs by IR or long-term H felis infection during progression to dysplasia. Deletion of IKKbeta in GECs led to increased apoptosis, reactive oxygen species, and cellular necrosis, and resulted in up-regulation of interleukin-1alpha and down-regulation of anti-apoptotic genes. Loss of IKKbeta in GECs resulted in worse inflammation and more rapid progression to gastric preneoplasia, while loss of IKKbeta in myeloid cells inhibited development of gastric atrophy. CONCLUSIONS The loss of IKKbeta/NF-kappaB signaling in GECs results in increased apoptosis and necrosis in response to cellular stress, and accelerated development of dysplasia by Helicobacter infection.
Collapse
Affiliation(s)
- Wataru Shibata
- Division of Digestive and Liver Disease, Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY
| | - Shigeo Takaishi
- Division of Digestive and Liver Disease, Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY
| | | | - D. Mark Pritchard
- Division of Gastroenterology, School of Clinical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Mark T. Whary
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA
| | - Arlin B. Rogers
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA
| | - James G. Fox
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA
| | - Kelly S. Betz
- Division of Digestive and Liver Disease, Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY
| | - Klaus H. Kaestner
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, PA
| | - Michael Karin
- Laboratory of Gene Regulation and Signal Transduction, Departments of Pharmacology and Pathology, Cancer Center, School of Medicine, University of California, San Diego, La Jolla, CA
| | - Timothy C. Wang
- Division of Digestive and Liver Disease, Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY
| |
Collapse
|
17
|
Thotala DK, Geng L, Dickey AK, Hallahan DE, Yazlovitskaya EM. A new class of molecular targeted radioprotectors: GSK-3beta inhibitors. Int J Radiat Oncol Biol Phys 2010; 76:557-65. [PMID: 20117291 DOI: 10.1016/j.ijrobp.2009.09.024] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Revised: 09/14/2009] [Accepted: 09/18/2009] [Indexed: 01/24/2023]
Abstract
PURPOSE Development of new treatments is critical to effective protection against radiation-induced injury. We investigate the potential of developing small-molecule inhibitors of glycogen synthase kinase 3beta (GSK-3beta)-SB216763 or SB415286-as radioprotective agents to attenuate intestinal injury. METHODS AND MATERIALS A survival study was done by use of C57BL/6J mice to evaluate the radioprotective effect of GSK-3beta inhibitors. Terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay and immunohistochemical staining for Bax and Bcl-2 were used to assess apoptosis in the small intestines of the treated mice. A clonogenic survival study, apoptosis assays (staining with annexin V or 4',6-diamidino-2-phenylindole), and immunoblot analysis of beta-catenin, Bcl-2, Bax, and caspase 3 were done by use of Rat intestinal epithelial cell line IEC-6 cells. RESULTS Pretreatment with SB415286 significantly improved survival of mice irradiated with 8 and 12 Gy. Mice pretreated with SB216763 or SB415286 showed a significant reduction in TUNEL- and Bax-positive cells and an increase in Bcl-2-positive cells in intestinal crypts at 4 and/or 12 h after radiation with 4 and/or 8 Gy compared with radiation alone. Pretreatment of irradiated IEC-6 cells with GSK-3beta inhibitors significantly increased clonogenic survival compared with cells treated with radiation alone. This increase was due to the attenuation of radiation-induced apoptosis, as shown by annexin V and 4',6-diamidino-2-phenylindole assays, as well as immunoblot analysis of Bcl-2, Bax, and caspase 3. CONCLUSIONS Glycogen synthase kinase 3beta small-molecule inhibitors protect mouse intestine from radiation-induced damage in cell culture and in vivo and improve survival of mice. Molecular mechanisms of this protection involve attenuated radiation-induced apoptosis regulated by Bcl-2, Bax, and caspase 3. Therefore GSK-3beta inhibitors reduce deleterious consequences of intestinal irradiation and thereby improve quality of life during radiation therapy.
Collapse
Affiliation(s)
- Dinesh K Thotala
- Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | | | | | | | | |
Collapse
|
18
|
Bowen JM, Tsykin A, Stringer AM, Logan RM, Gibson RJ, Keefe DMK. Kinetics and regional specificity of irinotecan-induced gene expression in the gastrointestinal tract. Toxicology 2010; 269:1-12. [PMID: 20097248 DOI: 10.1016/j.tox.2009.12.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 12/18/2009] [Accepted: 12/21/2009] [Indexed: 12/31/2022]
Abstract
Gastrointestinal toxicity remains a significant and dose-limiting complication of cancer treatment. While the pathophysiology is becoming clearer, considerable gaps in the knowledge remain surrounding the timing and site-specific gene changes which occur in response to insult. As such, this study aimed to assess gene expression profiles in a number of regions along the gastrointestinal tract following treatment with the chemotherapy agent, irinotecan, and correlate them with markers of cell death and tissue damage. Data analysis of microarray results found that genes involved in apoptosis, mitogen activated kinase (MAPK) signalling and inflammation were upregulated within 6h, while genes involved in cell proliferation, wound healing and blood vessel formation were upregulated at later time points up to 72 h. Cell death was significantly increased at 6 and 24h, and the stomach showed the lowest severity of overt tissue damage. Real time PCR of MAPK signalling pathway genes found that the jejunum and colon had significantly increased expression in a number of genes at 72 h, where as the stomach was unchanged. These results indicate that overall severity of tissue damage may be determined by precisely timed target gene responses specific to each region. Therapeutic targeting of key gene responses at the appropriate time point may prove to be effective for prevention of chemotherapy-induced gastrointestinal damage.
Collapse
|
19
|
Duckworth CA, Pritchard DM. Suppression of apoptosis, crypt hyperplasia, and altered differentiation in the colonic epithelia of bak-null mice. Gastroenterology 2009; 136:943-52. [PMID: 19185578 DOI: 10.1053/j.gastro.2008.11.036] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Revised: 09/16/2008] [Accepted: 11/13/2008] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS Members of the bcl-2 family of proteins are important determinants of cell fate. Bcl-2 and bcl-w have previously been identified as antiapoptotic members of this family that promote gastrointestinal epithelial cell survival. However, a proapoptotic family member that exerts important effects in the gastrointestinal tract has not yet been identified. We have therefore investigated intestinal epithelial apoptosis in bak-null mice. METHODS Apoptosis, mitosis, differentiated cell composition, and cell number were assessed on a cell positional basis in the small intestinal and colonic epithelia of bak-null mice and their C57BL/6 wild-type counterparts. Apoptosis was induced by 1-Gy gamma-irradiation or 10mg/kg azoxymethane (AOM). Aberrant crypt foci were induced by 3 weekly injections of 10mg/kg AOM. RESULTS The amount of spontaneous apoptosis in the colonic intercrypt table was reduced, and colonic crypt cell number and mitotic index were elevated in bak-null mice relative to C57BL/6 wild-type mice. Bak-null colonic crypts contained more goblet cells and fewer endocrine cells than those from C57BL/6 mice. Fewer colonic epithelial apoptotic cells were observed after gamma-radiation and AOM in bak-null mice, and these mice also displayed greater numbers of colonic AOM-induced aberrant crypt foci. None of these parameters differed in the small intestinal epithelium of bak-null mice compared with C57BL/6. CONCLUSIONS Bak prevents colonic crypt hyperplasia by regulating spontaneous apoptosis at the colonic intercrypt table region and also regulates damage-induced apoptosis in the colonic crypt. Deletion of bak in vivo results in altered colonic proliferation and differentiation, and causes increased susceptibility to colonic carcinogenesis.
Collapse
Affiliation(s)
- Carrie A Duckworth
- Division of Gastroenterology, University of Liverpool, Liverpool, United Kingdom
| | | |
Collapse
|
20
|
Zheng H, Pritchard DM, Yang X, Bennett E, Liu G, Liu C, Ai W. KLF4 gene expression is inhibited by the notch signaling pathway that controls goblet cell differentiation in mouse gastrointestinal tract. Am J Physiol Gastrointest Liver Physiol 2009; 296:G490-8. [PMID: 19109406 PMCID: PMC2660173 DOI: 10.1152/ajpgi.90393.2008] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In Kruppel-like factor (KLF)-4-deficient mice, colonic goblet cell numbers are significantly reduced. Goblet cell development is regulated by the Notch signaling pathway. The aim of this study was to examine whether Notch represses KLF4 expression to regulate goblet cell differentiation. We first detected that KLF4 gene expression was upregulated in a human progastrin-overexpressing mouse model where goblet cell hyperplasia has been observed. We then found that mice treated with a gamma-secretase inhibitor (compound E, 10 micromol/kg) for 24 h, which inhibits the Notch signaling pathway, had significantly increased KLF4 mRNA levels in small intestine and colon, accompanied by an increased number of KLF4-expressing cells at the bottom of crypts in small intestine and colon. In a colon cancer cell line (HCT116 cells), KLF4 promoter activity was inhibited by a constitutively active form of Notch1 (ICN1) by transient cotransfection assays. This inhibition was significantly compromised by a dominant-negative RBPjk, a repressive mediator of the Notch signaling pathway. An ICN1-responsive element was then mapped in the human KLF4 promoter between -151 and -122 nucleotides upstream of the transcriptional start site. It was also found that an intact ICN1-responsive element is required for ICN1 to inhibit KLF4 promoter activity by transient cotransfection assays. Our findings thus reveal a possible mechanism by which KLF4 is inhibited by Notch, which controls goblet cell differentiation in mouse gastrointestinal tract.
Collapse
Affiliation(s)
- Hai Zheng
- Departmen of Pathology, Microbiology and Immunology, University of South Carolina, Columbia, South Carolina; Division of Gastroenterology, School of Clinical Sciences, University of Liverpool, Liverpool, United Kingdom; Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, New York; and Sealy Center for Cancer Cell Biology and Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - D. Mark Pritchard
- Departmen of Pathology, Microbiology and Immunology, University of South Carolina, Columbia, South Carolina; Division of Gastroenterology, School of Clinical Sciences, University of Liverpool, Liverpool, United Kingdom; Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, New York; and Sealy Center for Cancer Cell Biology and Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Xiangdong Yang
- Departmen of Pathology, Microbiology and Immunology, University of South Carolina, Columbia, South Carolina; Division of Gastroenterology, School of Clinical Sciences, University of Liverpool, Liverpool, United Kingdom; Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, New York; and Sealy Center for Cancer Cell Biology and Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Elaine Bennett
- Departmen of Pathology, Microbiology and Immunology, University of South Carolina, Columbia, South Carolina; Division of Gastroenterology, School of Clinical Sciences, University of Liverpool, Liverpool, United Kingdom; Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, New York; and Sealy Center for Cancer Cell Biology and Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Gang Liu
- Departmen of Pathology, Microbiology and Immunology, University of South Carolina, Columbia, South Carolina; Division of Gastroenterology, School of Clinical Sciences, University of Liverpool, Liverpool, United Kingdom; Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, New York; and Sealy Center for Cancer Cell Biology and Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Chunming Liu
- Departmen of Pathology, Microbiology and Immunology, University of South Carolina, Columbia, South Carolina; Division of Gastroenterology, School of Clinical Sciences, University of Liverpool, Liverpool, United Kingdom; Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, New York; and Sealy Center for Cancer Cell Biology and Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Walden Ai
- Departmen of Pathology, Microbiology and Immunology, University of South Carolina, Columbia, South Carolina; Division of Gastroenterology, School of Clinical Sciences, University of Liverpool, Liverpool, United Kingdom; Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, New York; and Sealy Center for Cancer Cell Biology and Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| |
Collapse
|
21
|
Rotolo JA, Maj JG, Feldman R, Ren D, Haimovitz-Friedman A, Cordon-Cardo C, Cheng EHY, Kolesnick R, Fuks Z. Bax and Bak do not exhibit functional redundancy in mediating radiation-induced endothelial apoptosis in the intestinal mucosa. Int J Radiat Oncol Biol Phys 2008; 70:804-15. [PMID: 18191336 DOI: 10.1016/j.ijrobp.2007.11.043] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 11/09/2007] [Accepted: 11/09/2007] [Indexed: 01/13/2023]
Abstract
PURPOSE To address in vivo the issue of whether Bax and Bak are functionally redundant in signaling apoptosis, capable of substituting for each other. METHODS AND MATERIALS Mice were exposed to whole-body radiation, and endothelial cell apoptosis was quantified using double immunostaining with TUNEL and anti-CD31 antibody. Crypt survival was determined at 3.5 days after whole-body radiation by the microcolony survival assay. Actuarial animal survival was calculated by the product-limit Kaplan-Meier method, and autopsies were performed to establish cause of death. RESULTS Radiation exposure of Bax- and Bak-deficient mice, both expressing a wild-type acid sphingomyelinase (ASMase) phenotype, indicated that Bax and Bak are both mandatory, though mutually independent, for the intestinal endothelial apoptotic response. However, neither affected epithelial apoptosis at crypt positions 4-5, indicating specificity toward endothelium. Furthermore, Bax deficiency and Bak deficiency each individually mimicked ASMase deficiency in inhibiting crypt lethality in the microcolony assay and in rescuing mice from the lethal gastrointestinal syndrome. CONCLUSIONS The data indicate that Bax and Bak have nonredundant functional roles in the apoptotic response of the irradiated intestinal endothelium. The observation that Bax deficiency and Bak deficiency also protect crypts in the microcolony assay provides strong evidence that the microvascular apoptotic component is germane to the mechanism of radiation-induced damage to mouse intestines, regulating reproductive cell death of crypt stem cell clonogens.
Collapse
Affiliation(s)
- Jimmy A Rotolo
- Laboratory of Signal Transduction, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Przemeck SMC, Varro A, Berry D, Steele I, Wang TC, Dockray GJ, Pritchard DM. Hypergastrinemia increases gastric epithelial susceptibility to apoptosis. ACTA ACUST UNITED AC 2007; 146:147-56. [PMID: 17900712 DOI: 10.1016/j.regpep.2007.09.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2007] [Revised: 08/02/2007] [Accepted: 09/02/2007] [Indexed: 10/22/2022]
Abstract
Plasma concentrations of the hormone gastrin are elevated by Helicobacter pylori infection and by gastric atrophy. It has previously been proposed that gastrin acts as a cofactor during gastric carcinogenesis and hypergastrinemic transgenic INS-GAS mice are prone to developing gastric adenocarcinoma, particularly following H. pylori infection. We hypothesised that the increased risk of carcinogenesis in these animals may partly result from altered susceptibility of gastric epithelial cells to undergo apoptosis. Gastric corpus apoptosis was significantly increased 48 h after 12Gy gamma-radiation in mice rendered hypergastrinemic by transgenic (INS-GAS) or pharmacological (omeprazole treatment of FVB/N mice) methods and in both cases the effects were inhibited by the CCK-2 receptor antagonist YM022. However, no alteration in susceptibility to gamma-radiation-induced gastric epithelial apoptosis was observed in mice overexpressing progastrin or glycine-extended gastrin. Apoptosis was also significantly increased in gastric corpus biopsies obtained from H. pylori-infected humans with moderate degrees of hypergastrinemia. We conclude that hypergastrinemia specifically renders cells within the gastric corpus epithelium more susceptible to induction of apoptosis by radiation or H. pylori. Altered susceptibility to apoptosis may therefore be one factor predisposing to gastric carcinogenesis in INS-GAS mice and similar mechanisms may also be involved in humans.
Collapse
Affiliation(s)
- S M C Przemeck
- Division of Gastroenterology, School of Clinical Sciences, University of Liverpool, UK
| | | | | | | | | | | | | |
Collapse
|