1
|
Schöttker B, Gào X, Jansen EHJM, Brenner H. Associations of Human Colorectal Adenoma with Serum Biomarkers of Body Iron Stores, Inflammation and Antioxidant Protein Thiols. Antioxidants (Basel) 2021; 10:1195. [PMID: 34439443 PMCID: PMC8388983 DOI: 10.3390/antiox10081195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/19/2021] [Accepted: 07/20/2021] [Indexed: 12/12/2022] Open
Abstract
Red and processed meat consumption and obesity are established risk factors for colorectal adenoma (CRA). Adverse changes in biomarkers of body iron stores (total serum iron, ferritin, transferrin and transferrin saturation), inflammation (high-sensitivity C-reactive protein [hs-CRP]) and anti-oxidative capacity (total of thiol groups (-S-H) of proteins [SHP]) might reflect underlying mechanisms that could explain the association of red/processed meat consumption and obesity with CRA. Overall, 100 CRA cases (including 71 advanced cases) and 100 CRA-free controls were frequency-matched on age and sex and were selected from a colonoscopy screening cohort. Odds ratios (OR) and 95% confidence intervals (95%CI) for comparisons of top and bottom biomarker tertiles were derived from multivariable logistic regression models. Ferritin levels were significantly positively associated with red/processed meat consumption and hs-CRP levels with obesity. SHP levels were significantly inversely associated with obesity. Transferrin saturation was strongly positively associated with overall and advanced CRA (ORs [95%CIs]: 3.05 [1.30-7.19] and 2.71 [1.03-7.13], respectively). Due to the high correlation with transferrin saturation, results for total serum iron concentration were similar (but not statistically significant). Furthermore, SHP concentration was significantly inversely associated with advanced CRA (OR [95%CI]: 0.29 [0.10-0.84]) but not with overall CRA (OR [95%CI]: 0.65 [0.27-1.56]). Ferritin, transferrin, and hs-CRP levels were not associated with CRA. High transferrin saturation as a sign of iron overload and a low SHP concentration as a sign of redox imbalance in obese patients might reflect underlying mechanisms that could in part explain the associations of iron overload and obesity with CRA.
Collapse
Affiliation(s)
- Ben Schöttker
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center, 69120 Heidelberg, Germany; (X.G.); (H.B.)
- Network Aging Research, Heidelberg University, 69115 Heidelberg, Germany
| | - Xīn Gào
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center, 69120 Heidelberg, Germany; (X.G.); (H.B.)
- Network Aging Research, Heidelberg University, 69115 Heidelberg, Germany
| | - Eugène HJM Jansen
- Centre for Health Protection, National Institute of Public Health and the Environment, 3721 MA Bilthoven, The Netherlands;
| | - Hermann Brenner
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center, 69120 Heidelberg, Germany; (X.G.); (H.B.)
- Network Aging Research, Heidelberg University, 69115 Heidelberg, Germany
- Division of Preventive Oncology, German Cancer Research Center and National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany
- German Cancer Consortium (DKTK), German Cancer Research Center, 69120 Heidelberg, Germany
| |
Collapse
|
2
|
Abstract
Intestinal iron homeostasis is like the Zhong-Yong in traditional Chinese culture, which is a dynamic balance between Yin and Yang.
Collapse
Affiliation(s)
- Haoxuan Ding
- College of Animal Science
- Zhejiang University
- Key Laboratory of animal feed and nutrition of Zhejiang Province
- Hangzhou
- China
| | - Xiaonan Yu
- College of Animal Science
- Zhejiang University
- Key Laboratory of animal feed and nutrition of Zhejiang Province
- Hangzhou
- China
| | - Jie Feng
- College of Animal Science
- Zhejiang University
- Key Laboratory of animal feed and nutrition of Zhejiang Province
- Hangzhou
- China
| |
Collapse
|
3
|
Banjari I, Hjartåker A. Dietary sources of iron and vitamin B12: Is this the missing link in colorectal carcinogenesis? Med Hypotheses 2018; 116:105-110. [DOI: 10.1016/j.mehy.2018.05.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 03/04/2018] [Accepted: 05/07/2018] [Indexed: 12/22/2022]
|
4
|
He Q, Gao H, Gao M, Qi S, Yang K, Zhang Y, Wang J. Immunogenicity and safety of a novel tetanus toxoid-conjugated anti-gastrin vaccine in BALB/c mice. Vaccine 2018; 36:847-852. [PMID: 29306507 DOI: 10.1016/j.vaccine.2017.12.054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 12/10/2017] [Accepted: 12/18/2017] [Indexed: 02/07/2023]
Abstract
The objective of this study is to determine the immunogenicity and safety of our novel anti-gastrin vaccine that is composed of the common amino-terminal portions of human carboxy-amidated gastrin-17 (G17) and glycine-extended gastrin-17 (gly-G17) as well as the common carboxy-terminal portion of the gastrin precursor progastrin (in a 50:50 mixture) all covalently linked to tetanus toxoid (TT) via peptide spacers. The vaccine, or immunogen, was injected intramuscularly into the legs of BALB/c mice, which produced high serum titres of specific IgG antibodies and IFN-γ in their spleen cells, identifiable by enzyme-linked immunosorbent assay (ELISA) and enzyme-linked immunospot assay (ELISPOT), respectively. TT as the protein carrier effectively enhanced the antigenic epitopes' humoural and cellular immune responses, unlike the antigenic epitopes alone or the immunogen's adjuvant emulsion system (AES), all of which failed to provoke any obvious immune response. Notably, the animals' body weights increased significantly after immunization (P < .01), while their haematology and serum biochemistry were all generally normal, and the gross anatomy of their main organs (e.g., heart, liver, spleen, lung, kidney) showed no obvious histopathological changes.
Collapse
Affiliation(s)
- Qing He
- Biotechnology Center, Department of Pharmacy, Fourth Military Medical University, Xian, China; National Institutes for Food and Drug Control, Beijing, China
| | - Hua Gao
- National Institutes for Food and Drug Control, Beijing, China
| | | | | | - Kun Yang
- Biotechnology Center, Department of Pharmacy, Fourth Military Medical University, Xian, China
| | - Yingqi Zhang
- Biotechnology Center, Department of Pharmacy, Fourth Military Medical University, Xian, China
| | - Junzhi Wang
- Biotechnology Center, Department of Pharmacy, Fourth Military Medical University, Xian, China; National Institutes for Food and Drug Control, Beijing, China.
| |
Collapse
|
5
|
G9a regulates breast cancer growth by modulating iron homeostasis through the repression of ferroxidase hephaestin. Nat Commun 2017; 8:274. [PMID: 28819251 PMCID: PMC5561105 DOI: 10.1038/s41467-017-00350-9] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 06/23/2017] [Indexed: 01/16/2023] Open
Abstract
G9a, a H3K9 methyltransferase, shows elevated expression in many types of human cancers, particularly breast cancer. However, the tumorigenic mechanism of G9a is still far from clear. Here we report that G9a exerts its oncogenic function in breast cancer by repressing hephaestin and destruction cellular iron homeostasis. In the case of pharmacological inhibition or short hairpin RNA interference-mediated suppression of G9a, the expression and activity of hephaestin increases, leading to the observed decrease of intracellular labile iron content and the disturbance of breast cancer cell growth in vitro and in vivo. We also provide evidence that G9a interacts with HDAC1 and YY1 to form a multi-molecular complex that contributes to hephaestin silencing. Furthermore, high G9a expression and low hephaestin expression correlate with poor survival of breast cancer are investigated. All these suggest a G9a-dependent epigenetic program in the control of iron homeostasis and tumor growth in breast cancer. G9a is a histone methyltransferase highly expressed in several cancers including breast cancer. Here the authors propose a mechanism through which G9a promotes breast cancer by regulating iron metabolism through the repression of ferroxidase hephaestin.
Collapse
|
6
|
Baldwin GS, George GN, Pushie MJ. High Affinity Binding of Indium and Ruthenium Ions by Gastrins. PLoS One 2015; 10:e0140126. [PMID: 26457677 PMCID: PMC4601796 DOI: 10.1371/journal.pone.0140126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 09/21/2015] [Indexed: 11/22/2022] Open
Abstract
The peptide hormone gastrin binds two ferric ions with high affinity, and iron binding is essential for the biological activity of non-amidated forms of the hormone. Since gastrins act as growth factors in gastrointestinal cancers, and as peptides labelled with Ga and In isotopes are increasingly used for cancer diagnosis, the ability of gastrins to bind other metal ions was investigated systematically by absorption spectroscopy. The coordination structures of the complexes were characterized by extended X-ray absorption fine structure (EXAFS) spectroscopy. Changes in the absorption of gastrin in the presence of increasing concentrations of Ga3+ were fitted by a 2 site model with dissociation constants (Kd) of 3.3 x 10−7 and 1.1 x 10−6 M. Although the absorption of gastrin did not change upon the addition of In3+ ions, the changes in absorbance on Fe3+ ion binding in the presence of indium ions were fitted by a 2 site model with Kd values for In3+ of 6.5 x 10−15 and 1.7 x 10−7 M. Similar results were obtained with Ru3+ ions, although the Kd values for Ru3+ of 2.6 x 10−13 and 1.2 x 10−5 M were slightly larger than observed for In3+. The structures determined by EXAFS all had metal:gastrin stoichiometries of 2:1 but, while the metal ions in the Fe, Ga and In complexes were bridged by a carboxylate and an oxygen with a metal-metal separation of 3.0–3.3 Å, the Ru complex clearly demonstrated a short range Ru—Ru separation, which was significantly shorter, at 2.4 Å, indicative of a metal-metal bond. We conclude that gastrin selectively binds two In3+ or Ru3+ ions, and that the affinity of the first site for In3+ or Ru3+ ions is higher than for ferric ions. Some of the metal ion-gastrin complexes may be useful for cancer diagnosis and therapy.
Collapse
Affiliation(s)
- Graham S. Baldwin
- The University of Melbourne Department of Surgery, Austin Health, Heidelberg, Victoria 3084, Australia
- * E-mail:
| | - Graham N. George
- Molecular and Environmental Science Research Group Department of Geological Sciences, 114 Science Place, University of Saskatchewan, Saskatoon, S7N 5E2, Canada
| | - M. Jake Pushie
- Molecular and Environmental Science Research Group Department of Geological Sciences, 114 Science Place, University of Saskatchewan, Saskatoon, S7N 5E2, Canada
| |
Collapse
|
7
|
Díaz-Cambronero O, Matoses-Jaén S, García-Claudio N, García-Gregorio N, Molins-Espinosa J. [Preoperative management of anemia in oncologic surgery]. ACTA ACUST UNITED AC 2015; 62 Suppl 1:45-51. [PMID: 26320344 DOI: 10.1016/s0034-9356(15)30007-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Preoperative anemia in patients with cancer is highly prevalent, is associated with increased perioperative morbidity and is a risk factor for transfusion. There is evidence that patients who undergo transfusions have higher morbidity, increased cancer recurrence and poorer survival. The pathophysiology of anemia is multifactorial, with an inflammatory component to which chronic blood loss and nutritional deficiencies can be associated. Therefore, preoperative anemia in patients with cancer should be treated appropriately, given that there is sufficient time in the preoperative period. Of the currently available options, parenteral iron is an effective alternative, especially for those types of cancer that have an associated hemorrhagic component.
Collapse
Affiliation(s)
- O Díaz-Cambronero
- Servicio de Anestesiología y Reanimación, Hospital Universitari i Politècnic La Fe, Valencia, España.
| | - S Matoses-Jaén
- Servicio de Anestesiología y Reanimación, Hospital Universitari i Politècnic La Fe, Valencia, España
| | - N García-Claudio
- Servicio de Anestesiología y Reanimación, Hospital Universitari i Politècnic La Fe, Valencia, España
| | - N García-Gregorio
- Servicio de Anestesiología y Reanimación, Hospital Universitari i Politècnic La Fe, Valencia, España
| | - J Molins-Espinosa
- Servicio de Anestesiología y Reanimación, Hospital Universitari i Politècnic La Fe, Valencia, España
| |
Collapse
|
8
|
Laval M, Baldwin GS, Shulkes A, Marshall KM. Increased gastrin gene expression provides a physiological advantage to mice under hypoxic conditions. Am J Physiol Gastrointest Liver Physiol 2015; 308:G76-84. [PMID: 25394662 DOI: 10.1152/ajpgi.00344.2014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Hypoxia, or a low concentration of O2, is encountered in humans undertaking activities such as mountain climbing and scuba diving and is important pathophysiologically as a limiting factor in tumor growth. Although data on the interplay between hypoxia and gastrins are limited, gastrin expression is upregulated by hypoxia in gastrointestinal cancer cell lines, and gastrins counterbalance hypoxia by stimulating angiogenesis in vitro and in vivo. The aim of this study was to determine if higher concentrations of the gastrin precursor progastrin are protective against hypoxia in vivo. hGAS mice, which overexpress progastrin in the liver, and mice of the corresponding wild-type FVB/N strain were exposed to normoxia or hypoxia. Iron status was assessed by measurement of serum iron parameters, real-time PCR for mRNAs encoding critical iron regulatory proteins, and Perls' stain and atomic absorption spectrometry for tissue iron concentrations. FVB/N mice lost weight at a faster rate and had higher sickness scores than hGAS mice exposed to hypoxia. Serum iron levels were lower in hGAS than FVB/N mice and decreased further when the animals were exposed to hypoxia. The concentration of iron in the liver was strikingly lower in hGAS than FVB/N mice. We conclude that increased circulating concentrations of progastrin provide a physiological advantage against systemic hypoxia in mice, possibly by increasing the availability of iron stores. This is the first report of an association between progastrin overexpression, hypoxia, and iron homeostasis.
Collapse
Affiliation(s)
- Marie Laval
- Department of Surgery, University of Melbourne, Austin Health, Melbourne, Victoria, Australia
| | - Graham S Baldwin
- Department of Surgery, University of Melbourne, Austin Health, Melbourne, Victoria, Australia
| | - Arthur Shulkes
- Department of Surgery, University of Melbourne, Austin Health, Melbourne, Victoria, Australia
| | - Kathryn M Marshall
- Department of Surgery, University of Melbourne, Austin Health, Melbourne, Victoria, Australia
| |
Collapse
|
9
|
Westwood DA, Patel O, Baldwin GS. Gastrin mediates resistance to hypoxia-induced cell death in xenografts of the human colorectal cancer cell line LoVo. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:2471-80. [DOI: 10.1016/j.bbamcr.2014.06.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 06/11/2014] [Accepted: 06/24/2014] [Indexed: 10/25/2022]
|
10
|
Zhang SL, Li H, He X, Zhang RQ, Sun YH, Zhang CF, Wang CZ, Yuan CS. Alkaloids from Mahonia bealei posses anti-H⁺/K⁺-ATPase and anti-gastrin effects on pyloric ligation-induced gastric ulcer in rats. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2014; 21:1356-1363. [PMID: 25172799 DOI: 10.1016/j.phymed.2014.07.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 05/26/2014] [Accepted: 07/02/2014] [Indexed: 06/03/2023]
Abstract
The purpose of this study was to investigate the underlying mechanism(s) of the total alkaloids (TA) from Mahonia bealei in treating pyloric ligation-induced gastric ulcers in rats. Animals were sacrificed after 19 h of the ligation. Gastric acid, peptic activities, mucin levels, H(+)/K(+)-ATPase activities and the gastrin level were analyzed. To improve the accuracy of the observations, IPP 6.0 software was introduced to measure the area of ulcer. TA (18.56 mg/kg/day, i.g.) showed an antiulcer effect by significantly decreasing the gastric ulcer areas (11.28 mm(2)) compared with model group (26.36 mm(2)). The TA ulcer inhibition ratio was 57.2%, compared with the effect of the positive control, omeprazole (62.96%). The results also showed that TA had a significant effect in inhibiting the release of H(+)/K(+)-ATPase, reducing the content of gastrin and decreasing gastric acidity on experimental animals. However, the TA had no significant effects on gastric mucus secretion and pepsin activity. Data indicated that TA had gastric ulcer protective effects by modulating the H(+)/K(+)-ATPase activity and gastrin level. TA has a potential to be developed as a pharmacological agent for the treatment of gastric ulcers.
Collapse
Affiliation(s)
- Su-Li Zhang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, JS 210009, China
| | - Hui Li
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, JS 210009, China
| | - Xin He
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, JS 210000, China
| | - Run-Qi Zhang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, JS 210009, China
| | - Yu-He Sun
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, JS 210009, China
| | - Chun-Feng Zhang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, JS 210009, China; Tang Center of Herbal Medicine and Department of Anesthesia & Critical Care, University of Chicago, Chicago, IL 60637, USA.
| | - Chong-Zhi Wang
- Tang Center of Herbal Medicine and Department of Anesthesia & Critical Care, University of Chicago, Chicago, IL 60637, USA
| | - Chun-Su Yuan
- Tang Center of Herbal Medicine and Department of Anesthesia & Critical Care, University of Chicago, Chicago, IL 60637, USA
| |
Collapse
|
11
|
Zumbrennen-Bullough K, Babitt JL. The iron cycle in chronic kidney disease (CKD): from genetics and experimental models to CKD patients. Nephrol Dial Transplant 2013; 29:263-73. [PMID: 24235084 DOI: 10.1093/ndt/gft443] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Iron is essential for most living organisms but iron excess can be toxic. Cellular and systemic iron balance is therefore tightly controlled. Iron homeostasis is dysregulated in chronic kidney disease (CKD) and contributes to the anemia that is prevalent in this patient population. Iron supplementation is one cornerstone of anemia management in CKD patients, but has not been rigorously studied in large prospective randomized controlled trials. This review highlights important advances from genetic studies and animal models that have provided key insights into the molecular mechanisms governing iron homeostasis and its disturbance in CKD, and summarizes how these findings may yield advances in the care of this patient population.
Collapse
Affiliation(s)
- Kimberly Zumbrennen-Bullough
- Program in Anemia Signaling Research, Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | | |
Collapse
|
12
|
Asberg A, Thorstensen K, Irgens WØ, Romundstad PR, Hveem K. Cancer risk in HFE C282Y homozygotes: results from the HUNT 2 study. Scand J Gastroenterol 2013; 48:189-95. [PMID: 23281741 DOI: 10.3109/00365521.2012.752028] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE In addition to hepatocellular cancer, HFE C282Y homozygotes are reported to have increased risk of colorectal cancer and breast cancer. This study was done to further explore the cancer risk in C282Y homozygotes. MATERIAL AND METHODS We studied cancer incidence in 292 homozygotes and 62,568 others that participated in the HUNT 2 population screening in 1995-1997. Using Cox proportional hazard models, we estimated cancer hazard ratio as a function of C282Y homozygosity and several screening variables including serum transferrin saturation, alcohol consumption and daily smoking. RESULTS Cancer was diagnosed in 36 homozygotes, five of which had two cancer diagnoses. The overall cancer incidence was not increased in C282Y homozygotes (hazard ratio 1.10 [95% CI 0.60-2.03] in women and 0.94 [95% CI 0.53-1.66] in men). However, homozygous men had increased risk of colorectal cancer (hazard ratio 3.03 [95% CI 1.17-7.82], p = 0.022) and primary liver cancer (hazard ratio 54.0 [95% CI 2.68-1089], p = 0.009). The risk of breast cancer in homozygous women was not increased (hazard ratio 1.13 [95% CI 0.35-3.72]). Adjusted for other variables including C282Y homozygosity, very low and very high serum transferrin saturation were associated with increased overall cancer incidence. CONCLUSIONS C282Y homozygosity is associated with increased risk of colorectal cancer and hepatocellular cancer in men. In the general population, individuals with a very low or a very high serum transferrin saturation may have increased cancer risk.
Collapse
Affiliation(s)
- Arne Asberg
- Department of Clinical Chemistry, Trondheim University Hospital, Trondheim, Norway.
| | | | | | | | | |
Collapse
|
13
|
Abstract
PURPOSE OF REVIEW This review summarizes the past year's literature regarding the regulation of gastric exocrine and endocrine secretion, both basic science and clinical. RECENT FINDINGS Gastric acid secretion facilitates the digestion of protein as well as the absorption of iron, calcium, vitamin B12, and certain medications as well as prevents bacterial overgrowth, enteric infection, and possibly community-acquired pneumonia, spontaneous bacterial peritonitis, and IgE-mediated food allergy. It is regulated by neural (e.g., pituitary adenylate cyclase-activating peptide), hormonal (e.g., gastrin, ghrelin, and apelin), and paracrine (e.g., histamine) pathways as well as by chemical (e.g., amino acids) and bacterial stimuli (e.g., Helicobacter pylori). Novel peptides, which may possess physiologic function, have been identified in gastric mucosal neuroendocrine cells including parathyroid hormone-like hormone in histamine-secreting enterochromaffin-like cells and hepcidin in acid-secreting parietal cells. The secretion of hydrochloric acid by parietal cells involves translocation of the proton pump, HK-ATPase, to the apical membrane along with activation of apical chloride and potassium channels. Serum markers include chromogranin A for neuroendocrine tumors, pepsinogen I for gastric atrophy, and pepsinogen II for H. pylori infection. SUMMARY We continue to make progress in our understanding of the regulation of gastric acid secretion in health and disease.
Collapse
|
14
|
Singh P, Sarkar S, Kantara C, Maxwell C. Progastrin Peptides Increase the Risk of Developing Colonic Tumors: Impact on Colonic Stem Cells. CURRENT COLORECTAL CANCER REPORTS 2012; 8:277-289. [PMID: 23226720 DOI: 10.1007/s11888-012-0144-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Pre-neoplastic lesions (ACF, aberrant-crypt-foci; Hp, hyperplastic/dysplastic polyps) are believed to be precursors of sporadic colorectal-tumors (Ad, adenomas; AdCA, adenocarcinomas). ACF/Hp likely originate due to abnormal growth of colonic-crypts in response to aberrant queues in the microenvironment of colonic-crypts. Thus identifying factors which regulate homeostatic vs aberrant proliferation/apoptosis of colonocytes, especially stem/progenitor cells, may lead to effective preventative/treatment strategies. Based on this philosophy, role of growth-factors/peptide-hormones, potentially available in the circulation/microenvironment of colonic-crypts is being examined extensively. Since the time gastrins were discovered as trophic (growth) factors for gastrointestinal-cells, the effect of gastrins on the growth of normal/cancer cells has been investigated, leading to many discoveries. Seminal discoveries made in the area of gastrins and colon-cancer, as it relates to molecular pathways associated with formation of colonic tumors will be reviewed, and possible impact on diagnostic/preventative/treatment strategies will be discussed.
Collapse
Affiliation(s)
- Pomila Singh
- Department of Neuroscience and Cell Biology, UTMB, Galveston TX 77555
| | | | | | | |
Collapse
|
15
|
Bartnikas TB, Fleming MD, Schmidt PJ. Murine mutants in the study of systemic iron metabolism and its disorders: an update on recent advances. BIOCHIMICA ET BIOPHYSICA ACTA 2012; 1823:1444-50. [PMID: 22306267 PMCID: PMC3360922 DOI: 10.1016/j.bbamcr.2012.01.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 01/09/2012] [Accepted: 01/18/2012] [Indexed: 02/08/2023]
Abstract
Many past and recent advances in the field of iron metabolism have relied upon the use of mouse models of disease. These models have arisen spontaneously in breeder colonies or have been engineered for global or conditional ablation or overexpression of select genes. Full phenotypic characterization of these models typically involves maintenance on iron-loaded or -deficient diets, treatment with oxidative or hemolytic agents, breeding to other mutant lines or other stresses. In this review, we focus on systemic iron biology and the contributions that mouse model-based studies have made to the field. We have divided the field into three broad areas of research: dietary iron absorption, regulation of hepcidin expression and cellular iron metabolism. For each area, we begin with an overview of the current understanding of key molecular and cellular determinants then discuss recent advances. Finally, we conclude with brief comments on prospects for future study. This article is part of a Special Issue entitled: Cell Biology of Metals.
Collapse
|
16
|
Pantopoulos K, Porwal SK, Tartakoff A, Devireddy L. Mechanisms of mammalian iron homeostasis. Biochemistry 2012; 51:5705-24. [PMID: 22703180 DOI: 10.1021/bi300752r] [Citation(s) in RCA: 383] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Iron is vital for almost all organisms because of its ability to donate and accept electrons with relative ease. It serves as a cofactor for many proteins and enzymes necessary for oxygen and energy metabolism, as well as for several other essential processes. Mammalian cells utilize multiple mechanisms to acquire iron. Disruption of iron homeostasis is associated with various human diseases: iron deficiency resulting from defects in the acquisition or distribution of the metal causes anemia, whereas iron surfeit resulting from excessive iron absorption or defective utilization causes abnormal tissue iron deposition, leading to oxidative damage. Mammals utilize distinct mechanisms to regulate iron homeostasis at the systemic and cellular levels. These involve the hormone hepcidin and iron regulatory proteins, which collectively ensure iron balance. This review outlines recent advances in iron regulatory pathways as well as in mechanisms underlying intracellular iron trafficking, an important but less studied area of mammalian iron homeostasis.
Collapse
Affiliation(s)
- Kostas Pantopoulos
- Lady Davis Institute for Medical Research, Jewish General Hospital and Department of Medicine, McGill University, Montreal, QC, Canada
| | | | | | | |
Collapse
|
17
|
Xiao L, Kovac S, Chang M, Shulkes A, Baldwin GS, Patel O. Induction of gastrin expression in gastrointestinal cells by hypoxia or cobalt is independent of hypoxia-inducible factor (HIF). Endocrinology 2012; 153:3006-16. [PMID: 22593272 PMCID: PMC3380302 DOI: 10.1210/en.2011-2069] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Gastrin and its precursors have been shown to promote mitogenesis and angiogenesis in gastrointestinal tumors. Hypoxia stimulates tumor growth, but its effect on gastrin gene regulation has not been examined in detail. Here we have investigated the effect of hypoxia on the transcription of the gastrin gene in human gastric cancer (AGS) cells. Gastrin mRNA was measured by real-time PCR, gastrin peptides were measured by RIA, and gastrin promoter activity was measured by dual-luciferase reporter assay. Exposure to a low oxygen concentration (1%) increased gastrin mRNA concentrations in wild-type AGS cells (AGS) and in AGS cells overexpressing the gastrin receptor (AGS-cholecystokinin receptor 2) by 2.1 ± 0.4- and 4.1 ± 0.3-fold (P < 0.05), respectively. The hypoxia mimetic, cobalt chloride (300 μM), increased gastrin promoter activity in AGS cells by 2.4 ± 0.3-fold (P < 0.05), and in AGS-cholecystokinin receptor 2 cells by 4.0 ± 0.3-fold (P < 0.05), respectively. The observations that either deletion from the gastrin promoter of the putative binding sites for the transcription factor hypoxia-inducible factor 1 (HIF-1) or knockdown of either the HIF-1α or HIF-1β subunit did not affect gastrin promoter inducibility under hypoxia indicated that the hypoxic activation of the gastrin gene is likely HIF independent. Mutational analysis of previously identified Sp1 regulatory elements in the gastrin promoter also failed to abrogate the induction of promoter activity by hypoxia. The observations that hypoxia up-regulates the gastrin gene in AGS cells by HIF-independent mechanisms, and that this effect is enhanced by the presence of gastrin receptors, provide potential targets for gastrointestinal cancer therapy.
Collapse
Affiliation(s)
- Lin Xiao
- The University of Melbourne, Department of Surgery, Austin Health, Studley Road, Heidelberg, Victoria 3084, Australia
| | | | | | | | | | | |
Collapse
|
18
|
Regulation of iron transport and the role of transferrin. Biochim Biophys Acta Gen Subj 2012; 1820:188-202. [DOI: 10.1016/j.bbagen.2011.10.013] [Citation(s) in RCA: 303] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2011] [Revised: 10/27/2011] [Accepted: 10/30/2011] [Indexed: 12/15/2022]
|
19
|
Espey MG, Chen P, Chalmers B, Drisko J, Sun AY, Levine M, Chen Q. Pharmacologic ascorbate synergizes with gemcitabine in preclinical models of pancreatic cancer. Free Radic Biol Med 2011; 50:1610-9. [PMID: 21402145 PMCID: PMC3482496 DOI: 10.1016/j.freeradbiomed.2011.03.007] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 03/01/2011] [Accepted: 03/04/2011] [Indexed: 12/19/2022]
Abstract
Conventional treatment approaches have had little impact on the course of pancreatic cancer, which has the highest fatality rate among cancers. Gemcitabine, the primary therapeutic agent for pancreatic carcinoma, produces minimal survival benefit as a single agent. Therefore, numerous efforts have focused on gemcitabine combination treatments. Using a ratio design, this study established that combining pharmacologically achievable concentrations of ascorbate with gemcitabine resulted in a synergistic cytotoxic response in eight pancreatic tumor cell lines. Sensitization was evident regardless of inherent gemcitabine resistance and epithelial-mesenchymal phenotype. Our analysis suggested that the promiscuous oxidative actions of H(2)O(2) derived from pharmacologic ascorbate can culminate in synergism independent of the cancer cell's underlying phenotype and resistance to gemcitabine monotherapy. Gemcitabine-ascorbate combinations administered to mice bearing pancreatic tumor xenografts consistently enhanced inhibition of growth compared to gemcitabine alone, produced 50% growth inhibition in a tumor type not responsive to gemcitabine, and demonstrated a gemcitabine dose-sparing effect. These data support the testing of pharmacologic ascorbate in adjunctive treatments for cancers prone to high failure rates with conventional therapeutic regimens, such as pancreatic cancer.
Collapse
Affiliation(s)
- Michael Graham Espey
- Molecular and Clinical Nutrition Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ping Chen
- Program in Integrative Medicine, Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
- Department of Genetic and Molecular Biology, Xi'an Jiaotong University School of Medicine, Xi'an 710061, China
| | - Brian Chalmers
- Program in Integrative Medicine, Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Jeanne Drisko
- Program in Integrative Medicine, Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Andrew Y. Sun
- Molecular and Clinical Nutrition Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mark Levine
- Molecular and Clinical Nutrition Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Qi Chen
- Program in Integrative Medicine, Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
- Corresponding author. Fax: +1 913 945 6751. (Q. Chen)
| |
Collapse
|