Azita Monazzam - Academia.edu (original) (raw)
Papers by Azita Monazzam
Journal of biomolecular techniques, 2011
Many cancers can be diagnosed using positron emission tomography (PET) and PET can also be used t... more Many cancers can be diagnosed using positron emission tomography (PET) and PET can also be used to monitor how effective various treatments are in individual patients. Tumor spheroids are cancer cells grown on agar coated dishes forming a 3D structure. They are widely used in preclinical cancer research, where the multicellular tumor spheroid model is considered biologically and physiologically similar to in vivo grown tumors. In this study we have used Two-dimensional Difference Gel Electrophoresis (2-D DIGE) analysis to gain more insight in differences in protein expression as a result of drug treatment of multicellular tumor spheroids. 2-D DIGE can be used to identify possible new biomarkers for development of new PET tracers and drug targets. Combining 2-D DIGE and PET results can be used for improving diagnosis and treatment.
European Journal of Pharmaceutical Sciences, Feb 1, 2021
With the ambition of improving the management of pancreatic neuroendocrine tumors (P-NETs), we de... more With the ambition of improving the management of pancreatic neuroendocrine tumors (P-NETs), we developed and preliminary validated a novel fluorine-18 labelled HSP 90 ligand. Methods: A precursor containing methoxymethyl ethers protecting groups and a tosyl as leaving group was synthesized. The target compound was labeled with nucleophilic 18 F-fluoride and the protecting groups was subsequently removed with hydrochloric acid before purification. In vitro cell-and frozen section autoradiography and in vivo animal studies were performed. Results: The precursor was successfully synthesized and utilized in the 18 F-radiolabeling giving 0.5-1.0 GBq of pure product with a synthesis time of 70 min. In vitro experiments indicated a high specific binding, but in vivo studies showed no tumor uptake due to fast hepatobiliary metabolism and excretion. Conclusions: Despite the unfavorable in vivo properties of the tracer, the promising results from in vitro autoradiography experiments in frozen sections of P-NETs from surgical resection encourage us to continue the project aiming the improvement of in vivo properties of the tracer.
and its co-culture with malignant melanoma cell lines
<b>Copyright information:</b>Taken from "Application of the multicellular tumour... more <b>Copyright information:</b>Taken from "Application of the multicellular tumour spheroid model to screen PET tracers for analysis of early response of chemotherapy in breast cancer"http://breast-cancer-research.com/content/9/4/R45Breast cancer research : BCR 2007;9(4):R45-R45.Published online 22 Jul 2007PMCID:PMC2206720.
<b>Copyright information:</b>Taken from "Application of the multicellular tumour... more <b>Copyright information:</b>Taken from "Application of the multicellular tumour spheroid model to screen PET tracers for analysis of early response of chemotherapy in breast cancer"http://breast-cancer-research.com/content/9/4/R45Breast cancer research : BCR 2007;9(4):R45-R45.Published online 22 Jul 2007PMCID:PMC2206720.
Figure S1. Enhanced Akt phosphorylation in absence of menin is PI3K-Ca+â 2 dependent, but MAPK in... more Figure S1. Enhanced Akt phosphorylation in absence of menin is PI3K-Ca+â 2 dependent, but MAPK independent. Figure S2. Rictor in mTORC2 interacts with menin. Figure S3. Absence of menin or its downregulation do not affect the proliferation upon rapamycin treatment. Figure S4. Absence of menin reduces apoptotic signals. (PPTX 448 kb)
American journal of nuclear medicine and molecular imaging, 2012
The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorecta... more The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorectal cancer with trivalent bispecific antibody TF2 and two hapten molecules, [(67/68)Ga]Ga-IMP461 and [(67/68)Ga]Ga-IMP485 by means of pretargeting. Colorectal cancer tissue samples obtained from surgery at Uppsala University Hospital, were frozen fresh and cryosectioned. The two hapten molecules comprising 1,4,7-triazacyclononanetriacetic acid chelate moiety (NOTA) were labeled with (67)Ga or (68)Ga. The autoradiography was conducted by incubating the tissue samples with the bispecific antibody TF2, followed by washing and incubation with one of the radiolabeled hapten molecules. After washing, drying and exposure to phosphor imager plates, the autoradiograms were analyzed and compared to standard histochemistry (hematoxylin-eosin). Pronounced binding was found in the tissue from colorectal cancer using the bispecific antibody TF2 and either of the haptens [(67/68)Ga]Ga-IMP461 and [(67/68)...
The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorecta... more The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorectal cancer with trivalent bispecific antibody TF2 and two hapten molecules, (67/68Ga)Ga-IMP461 and (67/68Ga)Ga-IMP485 by means of pretargeting. Colorectal cancer tissue samples obtained from surgery at Uppsala University Hospital, were frozen fresh and cryosectioned. The two hapten molecules comprising 1,4,7-triazacyclononanetriacetic acid chelate moiety (NOTA) were labeled with 67Ga or 68Ga. The autoradiography was conducted by incubating the tissue samples with the bispecific antibody TF2, followed by washing and incubation with one of the radiolabeled hapten molecules. After washing, drying and exposure to phosphor imager plates, the autoradiograms were analyzed and compared to standard histochemistry (hematoxylin-eosin). Pronounced binding was found in the tissue from colorectal cancer us- ing the bispecific antibody TF2 and either of the haptens (67/68Ga)Ga-IMP461 and (67/68Ga)Ga-IMP4...
Positron Emission Tomography (PET) has gained an important roll in clinical for diagnosis, stagin... more Positron Emission Tomography (PET) has gained an important roll in clinical for diagnosis, staging and prognosis of a range of cancer types. Utilization of PET for monitoring and evaluation of canc ...
Scientific Reports
Adrenocortical carcinoma is a rare aggressive disease commonly recurring regardless of radical su... more Adrenocortical carcinoma is a rare aggressive disease commonly recurring regardless of radical surgery. Although data on genomic alterations in malignant tumors are accumulating, knowledge of molecular events of importance for initiation of adrenocortical transformation is scarce. In an attempt to recognize early molecular alterations, we used adrenals from young multiple endocrine neoplasia type 1 conventional knock-out mice (Men1+/−) closely mimicking the human MEN1 trait (i.e. transformation of pituitary, parathyroid, endocrine pancreatic, and adrenocortical cells). MicroRNA array and hierarchical clustering showed a distinct pattern. Twenty miRNAs were significantly upregulated and eleven were downregulated in Men1+/− compared to wild type littermates. The latter included the known suppressor miRNA miR-486-3p, which was chosen for transfection in human adrenocortical carcinoma cell lines H295R and SW13. Cell growth decreased in miR-486-3p overexpressing clones and levels of the ...
![Research paper thumbnail of s response to reviews Title : Masked Volume Wise Principal Component Analysis Improves Signal Detection , Separation and Analysis of Small Adrenocortical Tumors in Dynamic [ 11 C ]-Metomidate Positron Emission Tomography](https://attachments.academia-assets.com/77357344/thumbnails/1.jpg)
](The authors wish to thank you and the reviewers for fruitful and useful comments in clarifying so... more The authors wish to thank you and the reviewers for fruitful and useful comments in clarifying some points, and improving the content of the manuscript. Now, we have revised the manuscript based on reviewers' comments and it has been checked carefully by a native English speaker as well. We hope that you and the reviewers are satisfied with the revised version. If you need further information, please do not hesitate to contact us.
![Research paper thumbnail of Para-chloro-2-[18F]fluoroethyl-etomidate: A promising new PET radiotracer for adrenocortical imaging](https://attachments.academia-assets.com/77357340/thumbnails/1.jpg)
](Introduction: [11C]Metomidate ([11C]MTO), the methyl ester analogue of etomidate, was developed a... more Introduction: [11C]Metomidate ([11C]MTO), the methyl ester analogue of etomidate, was developed as a positron emission tomography (PET) radiotracer for adrenocortical tumours and has also been suggested for imaging in primary aldosteronism (PA). A disadvantage of [11C]MTO is the rather high non-specific binding in the liver, which impacts both visualization and quantification of the uptake in the right adrenal gland. Furthermore, the short 20-minute half-life of carbon-11 is a logistic challenge in the clinical setting. Objectives: The aim of this study was to further evaluate the previously published fluorine-18 (T1/2=109.5 min) etomidate analogue, para-chloro-2-[18F]fluoroethyl etomidate; [18F]CETO, as an adrenal PET tracer. Methods: In vitro experiments included autoradiography on human and cynomolgus monkey (non-human primate, NHP) tissues and binding studies on adrenal tissue from NHPs. In vivo studies with [18F]CETO in mice, rats and NHP, using PET and CT/MRI, assessed biodist...
Scientific Reports
Among patients with the rare diagnosis of pancreatic neuroendocrine tumor (P-NET), a substantial ... more Among patients with the rare diagnosis of pancreatic neuroendocrine tumor (P-NET), a substantial proportion suffer from the inherited cancer syndrome multiple endocrine neoplasia type 1 (MEN1), which is caused by germline mutations of the MEN1 suppressor gene. Somatic mutations and loss of the MEN1 protein (menin) are frequently also found in sporadic P-NETs. Thus, a human neuroendocrine pancreatic cell line with biallelic inactivation of MEN1 might be of value for studying tumorigenesis. We used the polyclonal human P-NET cell line BON1, which expresses menin, serotonin, chromogranin A and neurotensin, to generate a monoclonal stable MEN1 knockout BON1 cell line (MEN1-KO-BON1) by CRISPR/Cas9 editing. Changes in morphology, hormone secretion, and proliferation were analyzed, and proteomics were assessed using nanoLC-MS/MS and Ingenuity Pathway Analysis (IPA). The menin-lacking MEN1-KO-BON1 cells had increased chromogranin A production and were smaller, more homogenous, rounder and g...
Cell Communication and Signaling
Background: Mammalian target of rapamycin (mTOR) is a master regulator of various cellular respon... more Background: Mammalian target of rapamycin (mTOR) is a master regulator of various cellular responses by forming two functional complexes, mTORC1 and mTORC2. mTOR signaling is frequently dysregulated in pancreatic neuroendocrine tumors (PNETs). mTOR inhibitors have been used in attempts to treat these lesions, and prolonged progression free survival has been recorded. If this holds true also for the multiple endocrine neoplasia type 1 (MEN1) associated PNETs is yet unclear. We investigated the relationship between expression of the MEN1 protein menin and mTOR signaling in the presence or absence of the mTOR inhibitor rapamycin. Methods: In addition to use of menin wild type and menin-null mouse embryonic fibroblasts (MEFs), menin was silenced by siRNA in pancreatic neuroendocrine tumor cell line BON-1. Panels of protein phosphorylation, as activation markers downstream of PI3k-mTOR-Akt pathways, as well as menin expression were evaluated by immunoblotting. The impact of menin expression in the presence and absence of rapamycin was determinate upon Wound healing, migration and proliferation in MEFs and BON1 cells. Results: PDGF-BB markedly increased phosphorylation of mTORC2 substrate Akt, at serine 473 (S473) and threonine 450 (T450) in menin −/− MEFs but did not alter phosphorylation of mTORC1 substrates ribosomal protein S6 or eIF4B. Acute rapamycin treatment by mTORC1-S6 inhibition caused a greater enhancement of Akt phosphorylation on S473 in menin −/− cells as compared to menin +/+ MEFs (116% vs 38%). Chronic rapamycin treatment, which inhibits both mTORC1and 2, reduced Akt phosphorylation of S473 to a lesser extent in menin −/− MEFs than menin +/+ MEFs (25% vs 75%). Silencing of menin expression in human PNET cell line (BON1) also enhanced Akt phosphorylation at S473, but not activation of mTORC1. Interestingly, silencing menin in BON1 cells elevated S473 phosphorylation of Akt in both acute and chronic treatments with rapamycin. Finally, we show that the inhibitory effect of rapamycin on serum mediated wound healing and cell migration is impaired in menin −/− MEFs, as well as in menin-silenced BON1 cells. Conclusions: Menin is involved in regulatory mechanism between the two mTOR complexes, and its reduced expression is accompanied with increased mTORC2-Akt signaling, which consequently impairs anti-migratory effect of rapamycin.
![Research paper thumbnail of Increased Expression of GLP-1R in Proliferating Islets of Men1 Mice is Detectable by [68Ga]Ga-DO3A-VS-Cys40-Exendin-4 /PET](https://attachments.academia-assets.com/72237323/thumbnails/1.jpg)
](Scientific Reports
Multiple endocrine neoplasia type 1 (MEN1) is an endocrine tumor syndrome caused by heterozygous ... more Multiple endocrine neoplasia type 1 (MEN1) is an endocrine tumor syndrome caused by heterozygous mutations in the MEN1 tumor suppressor gene. The MEN1 pancreas of the adolescent gene carrier frequently contain diffusely spread pre-neoplasias and microadenomas, progressing to macroscopic and potentially malignant pancreatic neuroendocrine tumors (P-NET), which represents the major death cause in MEN1. The unveiling of the molecular mechanism of P-NET which is not currently understood fully to allow the optimization of diagnostics and treatment. Glucagon-like peptide 1 (GLP-1) pathway is essential in islet regeneration, i.e. inhibition of β-cell apoptosis and enhancement of β-cell proliferation, yet involvement of GLP-1 in MEN1 related P-NET has not yet been demonstrated. The objective of this work was to investigate if normal sized islets of Men1 heterozygous mice have increased Glucagon-like peptide-1 receptor (GLP-1R) expression compared to wild type islets, and if this increase is detectable in vivo with positron emission tomography (PET) using [68Ga]Ga-DO3A-VS-Cys40-Exendin-4 (68Ga-Exendin-4). 68Ga-Exendin-4 showed potential for early lesion detection in MEN1 pancreas due to increased GLP1R expression.
Bergström M. "Application of Multicellular tumour spheroid model to screen PET-tracers to monitor... more Bergström M. "Application of Multicellular tumour spheroid model to screen PET-tracers to monitor early response of chemotherapy in cancer, " Patent, PH0515c, (2006). * Clonogenic assay or colony formation assay is an in vitro cell survival assay based on the ability of a single cell to grow into a colony † An anticancer drug that belongs to the family of drugs called antimetabolites
![Research paper thumbnail of Multicellular tumour spheroid as a model for evaluation of [18F]FDG as biomarker for breast cancer treatment monitoring](https://attachments.academia-assets.com/72237320/thumbnails/1.jpg)
](Cancer cell international, Jan 23, 2006
In order to explore a pre-clinical method to evaluate if [18F]FDG is valid for monitoring early r... more In order to explore a pre-clinical method to evaluate if [18F]FDG is valid for monitoring early response, we investigated the uptake of FDG in Multicellular tumour spheroids (MTS) without and with treatment with five routinely used chemotherapy agents in breast cancer. The response to each anticancer treatment was evaluated by measurement of the [18F]FDG uptake and viable volume of the MTSs after 2 and 3 days of treatment. The effect of Paclitaxel and Docetaxel on [18F]FDG uptake per viable volume was more evident in BT474 (up to 55% decrease) than in MCF-7 (up to 25% decrease). Doxorubicin reduced the [18F]FDG uptake per viable volume more noticeable in MCF-7 (25%) than in BT474 MTSs. Tamoxifen reduced the [18F]FDG uptake per viable volume only in MCF-7 at the highest dose of 1 microM. No effect of Imatinib was observed. MTS was shown to be appropriate to investigate the potential of FDG-PET for early breast cancer treatment monitoring; the treatment effect can be observed before a...
Cancer cell international, Jan 14, 2005
Considering the width and importance of using Multicellular Tumor Spheroids (MTS) in oncology res... more Considering the width and importance of using Multicellular Tumor Spheroids (MTS) in oncology research, size determination of MTSs by an accurate and fast method is essential. In the present study an effective, fast and semi-automated method, SASDM, was developed to determinate the size of MTSs. The method was applied and tested in MTSs of three different cell-lines. Frozen section autoradiography and Hemotoxylin Eosin (H&E) staining was used for further confirmation. SASDM was shown to be effective, user-friendly, and time efficient, and to be more precise than the traditional methods and it was applicable for MTSs of different cell-lines. Furthermore, the results of image analysis showed high correspondence to the results of autoradiography and staining. The combination of assessment of metabolic condition and image analysis in MTSs provides a good model to evaluate the effect of various anti-cancer treatments.
American journal of nuclear medicine and molecular imaging, 2012
The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorecta... more The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorectal cancer with trivalent bispecific antibody TF2 and two hapten molecules, [(67/68)Ga]Ga-IMP461 and [(67/68)Ga]Ga-IMP485 by means of pretargeting. Colorectal cancer tissue samples obtained from surgery at Uppsala University Hospital, were frozen fresh and cryosectioned. The two hapten molecules comprising 1,4,7-triazacyclononanetriacetic acid chelate moiety (NOTA) were labeled with (67)Ga or (68)Ga. The autoradiography was conducted by incubating the tissue samples with the bispecific antibody TF2, followed by washing and incubation with one of the radiolabeled hapten molecules. After washing, drying and exposure to phosphor imager plates, the autoradiograms were analyzed and compared to standard histochemistry (hematoxylin-eosin). Pronounced binding was found in the tissue from colorectal cancer using the bispecific antibody TF2 and either of the haptens [(67/68)Ga]Ga-IMP461 and [(67/68)...
Progress in Neuro-Psychopharmacology and Biological Psychiatry, 2002
Anabolic-androgenic steroids (AAS) have recently been shown to induce neurochemical alterations i... more Anabolic-androgenic steroids (AAS) have recently been shown to induce neurochemical alterations in areas of the male rat CNS related to behavioural changes that have been observed among AAS misusers. In the present study, positron emission tomography (PET) is suggested as a suitable in vivo method in order to visualize the density of the dopamine transporter ([ 11 C]-FE-b-CIT) as well as the dopamine D 1-like ([ 11 C]-(+)-SCH23390) and the D 2-like receptors ([ 11 C]-raclopride) in the male rat brain. Chronic treatment with the AAS nandrolone decanoate (15 mg/kg/day for 14 days) caused an up-regulation of the binding potential of the dopamine transporter in the striatum.
Journal of biomolecular techniques, 2011
Many cancers can be diagnosed using positron emission tomography (PET) and PET can also be used t... more Many cancers can be diagnosed using positron emission tomography (PET) and PET can also be used to monitor how effective various treatments are in individual patients. Tumor spheroids are cancer cells grown on agar coated dishes forming a 3D structure. They are widely used in preclinical cancer research, where the multicellular tumor spheroid model is considered biologically and physiologically similar to in vivo grown tumors. In this study we have used Two-dimensional Difference Gel Electrophoresis (2-D DIGE) analysis to gain more insight in differences in protein expression as a result of drug treatment of multicellular tumor spheroids. 2-D DIGE can be used to identify possible new biomarkers for development of new PET tracers and drug targets. Combining 2-D DIGE and PET results can be used for improving diagnosis and treatment.
European Journal of Pharmaceutical Sciences, Feb 1, 2021
With the ambition of improving the management of pancreatic neuroendocrine tumors (P-NETs), we de... more With the ambition of improving the management of pancreatic neuroendocrine tumors (P-NETs), we developed and preliminary validated a novel fluorine-18 labelled HSP 90 ligand. Methods: A precursor containing methoxymethyl ethers protecting groups and a tosyl as leaving group was synthesized. The target compound was labeled with nucleophilic 18 F-fluoride and the protecting groups was subsequently removed with hydrochloric acid before purification. In vitro cell-and frozen section autoradiography and in vivo animal studies were performed. Results: The precursor was successfully synthesized and utilized in the 18 F-radiolabeling giving 0.5-1.0 GBq of pure product with a synthesis time of 70 min. In vitro experiments indicated a high specific binding, but in vivo studies showed no tumor uptake due to fast hepatobiliary metabolism and excretion. Conclusions: Despite the unfavorable in vivo properties of the tracer, the promising results from in vitro autoradiography experiments in frozen sections of P-NETs from surgical resection encourage us to continue the project aiming the improvement of in vivo properties of the tracer.
and its co-culture with malignant melanoma cell lines
<b>Copyright information:</b>Taken from "Application of the multicellular tumour... more <b>Copyright information:</b>Taken from "Application of the multicellular tumour spheroid model to screen PET tracers for analysis of early response of chemotherapy in breast cancer"http://breast-cancer-research.com/content/9/4/R45Breast cancer research : BCR 2007;9(4):R45-R45.Published online 22 Jul 2007PMCID:PMC2206720.
<b>Copyright information:</b>Taken from "Application of the multicellular tumour... more <b>Copyright information:</b>Taken from "Application of the multicellular tumour spheroid model to screen PET tracers for analysis of early response of chemotherapy in breast cancer"http://breast-cancer-research.com/content/9/4/R45Breast cancer research : BCR 2007;9(4):R45-R45.Published online 22 Jul 2007PMCID:PMC2206720.
Figure S1. Enhanced Akt phosphorylation in absence of menin is PI3K-Ca+â 2 dependent, but MAPK in... more Figure S1. Enhanced Akt phosphorylation in absence of menin is PI3K-Ca+â 2 dependent, but MAPK independent. Figure S2. Rictor in mTORC2 interacts with menin. Figure S3. Absence of menin or its downregulation do not affect the proliferation upon rapamycin treatment. Figure S4. Absence of menin reduces apoptotic signals. (PPTX 448 kb)
American journal of nuclear medicine and molecular imaging, 2012
The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorecta... more The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorectal cancer with trivalent bispecific antibody TF2 and two hapten molecules, [(67/68)Ga]Ga-IMP461 and [(67/68)Ga]Ga-IMP485 by means of pretargeting. Colorectal cancer tissue samples obtained from surgery at Uppsala University Hospital, were frozen fresh and cryosectioned. The two hapten molecules comprising 1,4,7-triazacyclononanetriacetic acid chelate moiety (NOTA) were labeled with (67)Ga or (68)Ga. The autoradiography was conducted by incubating the tissue samples with the bispecific antibody TF2, followed by washing and incubation with one of the radiolabeled hapten molecules. After washing, drying and exposure to phosphor imager plates, the autoradiograms were analyzed and compared to standard histochemistry (hematoxylin-eosin). Pronounced binding was found in the tissue from colorectal cancer using the bispecific antibody TF2 and either of the haptens [(67/68)Ga]Ga-IMP461 and [(67/68)...
The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorecta... more The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorectal cancer with trivalent bispecific antibody TF2 and two hapten molecules, (67/68Ga)Ga-IMP461 and (67/68Ga)Ga-IMP485 by means of pretargeting. Colorectal cancer tissue samples obtained from surgery at Uppsala University Hospital, were frozen fresh and cryosectioned. The two hapten molecules comprising 1,4,7-triazacyclononanetriacetic acid chelate moiety (NOTA) were labeled with 67Ga or 68Ga. The autoradiography was conducted by incubating the tissue samples with the bispecific antibody TF2, followed by washing and incubation with one of the radiolabeled hapten molecules. After washing, drying and exposure to phosphor imager plates, the autoradiograms were analyzed and compared to standard histochemistry (hematoxylin-eosin). Pronounced binding was found in the tissue from colorectal cancer us- ing the bispecific antibody TF2 and either of the haptens (67/68Ga)Ga-IMP461 and (67/68Ga)Ga-IMP4...
Positron Emission Tomography (PET) has gained an important roll in clinical for diagnosis, stagin... more Positron Emission Tomography (PET) has gained an important roll in clinical for diagnosis, staging and prognosis of a range of cancer types. Utilization of PET for monitoring and evaluation of canc ...
Scientific Reports
Adrenocortical carcinoma is a rare aggressive disease commonly recurring regardless of radical su... more Adrenocortical carcinoma is a rare aggressive disease commonly recurring regardless of radical surgery. Although data on genomic alterations in malignant tumors are accumulating, knowledge of molecular events of importance for initiation of adrenocortical transformation is scarce. In an attempt to recognize early molecular alterations, we used adrenals from young multiple endocrine neoplasia type 1 conventional knock-out mice (Men1+/−) closely mimicking the human MEN1 trait (i.e. transformation of pituitary, parathyroid, endocrine pancreatic, and adrenocortical cells). MicroRNA array and hierarchical clustering showed a distinct pattern. Twenty miRNAs were significantly upregulated and eleven were downregulated in Men1+/− compared to wild type littermates. The latter included the known suppressor miRNA miR-486-3p, which was chosen for transfection in human adrenocortical carcinoma cell lines H295R and SW13. Cell growth decreased in miR-486-3p overexpressing clones and levels of the ...
The authors wish to thank you and the reviewers for fruitful and useful comments in clarifying so... more The authors wish to thank you and the reviewers for fruitful and useful comments in clarifying some points, and improving the content of the manuscript. Now, we have revised the manuscript based on reviewers' comments and it has been checked carefully by a native English speaker as well. We hope that you and the reviewers are satisfied with the revised version. If you need further information, please do not hesitate to contact us.
Introduction: [11C]Metomidate ([11C]MTO), the methyl ester analogue of etomidate, was developed a... more Introduction: [11C]Metomidate ([11C]MTO), the methyl ester analogue of etomidate, was developed as a positron emission tomography (PET) radiotracer for adrenocortical tumours and has also been suggested for imaging in primary aldosteronism (PA). A disadvantage of [11C]MTO is the rather high non-specific binding in the liver, which impacts both visualization and quantification of the uptake in the right adrenal gland. Furthermore, the short 20-minute half-life of carbon-11 is a logistic challenge in the clinical setting. Objectives: The aim of this study was to further evaluate the previously published fluorine-18 (T1/2=109.5 min) etomidate analogue, para-chloro-2-[18F]fluoroethyl etomidate; [18F]CETO, as an adrenal PET tracer. Methods: In vitro experiments included autoradiography on human and cynomolgus monkey (non-human primate, NHP) tissues and binding studies on adrenal tissue from NHPs. In vivo studies with [18F]CETO in mice, rats and NHP, using PET and CT/MRI, assessed biodist...
Scientific Reports
Among patients with the rare diagnosis of pancreatic neuroendocrine tumor (P-NET), a substantial ... more Among patients with the rare diagnosis of pancreatic neuroendocrine tumor (P-NET), a substantial proportion suffer from the inherited cancer syndrome multiple endocrine neoplasia type 1 (MEN1), which is caused by germline mutations of the MEN1 suppressor gene. Somatic mutations and loss of the MEN1 protein (menin) are frequently also found in sporadic P-NETs. Thus, a human neuroendocrine pancreatic cell line with biallelic inactivation of MEN1 might be of value for studying tumorigenesis. We used the polyclonal human P-NET cell line BON1, which expresses menin, serotonin, chromogranin A and neurotensin, to generate a monoclonal stable MEN1 knockout BON1 cell line (MEN1-KO-BON1) by CRISPR/Cas9 editing. Changes in morphology, hormone secretion, and proliferation were analyzed, and proteomics were assessed using nanoLC-MS/MS and Ingenuity Pathway Analysis (IPA). The menin-lacking MEN1-KO-BON1 cells had increased chromogranin A production and were smaller, more homogenous, rounder and g...
Cell Communication and Signaling
Background: Mammalian target of rapamycin (mTOR) is a master regulator of various cellular respon... more Background: Mammalian target of rapamycin (mTOR) is a master regulator of various cellular responses by forming two functional complexes, mTORC1 and mTORC2. mTOR signaling is frequently dysregulated in pancreatic neuroendocrine tumors (PNETs). mTOR inhibitors have been used in attempts to treat these lesions, and prolonged progression free survival has been recorded. If this holds true also for the multiple endocrine neoplasia type 1 (MEN1) associated PNETs is yet unclear. We investigated the relationship between expression of the MEN1 protein menin and mTOR signaling in the presence or absence of the mTOR inhibitor rapamycin. Methods: In addition to use of menin wild type and menin-null mouse embryonic fibroblasts (MEFs), menin was silenced by siRNA in pancreatic neuroendocrine tumor cell line BON-1. Panels of protein phosphorylation, as activation markers downstream of PI3k-mTOR-Akt pathways, as well as menin expression were evaluated by immunoblotting. The impact of menin expression in the presence and absence of rapamycin was determinate upon Wound healing, migration and proliferation in MEFs and BON1 cells. Results: PDGF-BB markedly increased phosphorylation of mTORC2 substrate Akt, at serine 473 (S473) and threonine 450 (T450) in menin −/− MEFs but did not alter phosphorylation of mTORC1 substrates ribosomal protein S6 or eIF4B. Acute rapamycin treatment by mTORC1-S6 inhibition caused a greater enhancement of Akt phosphorylation on S473 in menin −/− cells as compared to menin +/+ MEFs (116% vs 38%). Chronic rapamycin treatment, which inhibits both mTORC1and 2, reduced Akt phosphorylation of S473 to a lesser extent in menin −/− MEFs than menin +/+ MEFs (25% vs 75%). Silencing of menin expression in human PNET cell line (BON1) also enhanced Akt phosphorylation at S473, but not activation of mTORC1. Interestingly, silencing menin in BON1 cells elevated S473 phosphorylation of Akt in both acute and chronic treatments with rapamycin. Finally, we show that the inhibitory effect of rapamycin on serum mediated wound healing and cell migration is impaired in menin −/− MEFs, as well as in menin-silenced BON1 cells. Conclusions: Menin is involved in regulatory mechanism between the two mTOR complexes, and its reduced expression is accompanied with increased mTORC2-Akt signaling, which consequently impairs anti-migratory effect of rapamycin.
Scientific Reports
Multiple endocrine neoplasia type 1 (MEN1) is an endocrine tumor syndrome caused by heterozygous ... more Multiple endocrine neoplasia type 1 (MEN1) is an endocrine tumor syndrome caused by heterozygous mutations in the MEN1 tumor suppressor gene. The MEN1 pancreas of the adolescent gene carrier frequently contain diffusely spread pre-neoplasias and microadenomas, progressing to macroscopic and potentially malignant pancreatic neuroendocrine tumors (P-NET), which represents the major death cause in MEN1. The unveiling of the molecular mechanism of P-NET which is not currently understood fully to allow the optimization of diagnostics and treatment. Glucagon-like peptide 1 (GLP-1) pathway is essential in islet regeneration, i.e. inhibition of β-cell apoptosis and enhancement of β-cell proliferation, yet involvement of GLP-1 in MEN1 related P-NET has not yet been demonstrated. The objective of this work was to investigate if normal sized islets of Men1 heterozygous mice have increased Glucagon-like peptide-1 receptor (GLP-1R) expression compared to wild type islets, and if this increase is detectable in vivo with positron emission tomography (PET) using [68Ga]Ga-DO3A-VS-Cys40-Exendin-4 (68Ga-Exendin-4). 68Ga-Exendin-4 showed potential for early lesion detection in MEN1 pancreas due to increased GLP1R expression.
Bergström M. "Application of Multicellular tumour spheroid model to screen PET-tracers to monitor... more Bergström M. "Application of Multicellular tumour spheroid model to screen PET-tracers to monitor early response of chemotherapy in cancer, " Patent, PH0515c, (2006). * Clonogenic assay or colony formation assay is an in vitro cell survival assay based on the ability of a single cell to grow into a colony † An anticancer drug that belongs to the family of drugs called antimetabolites
Cancer cell international, Jan 23, 2006
In order to explore a pre-clinical method to evaluate if [18F]FDG is valid for monitoring early r... more In order to explore a pre-clinical method to evaluate if [18F]FDG is valid for monitoring early response, we investigated the uptake of FDG in Multicellular tumour spheroids (MTS) without and with treatment with five routinely used chemotherapy agents in breast cancer. The response to each anticancer treatment was evaluated by measurement of the [18F]FDG uptake and viable volume of the MTSs after 2 and 3 days of treatment. The effect of Paclitaxel and Docetaxel on [18F]FDG uptake per viable volume was more evident in BT474 (up to 55% decrease) than in MCF-7 (up to 25% decrease). Doxorubicin reduced the [18F]FDG uptake per viable volume more noticeable in MCF-7 (25%) than in BT474 MTSs. Tamoxifen reduced the [18F]FDG uptake per viable volume only in MCF-7 at the highest dose of 1 microM. No effect of Imatinib was observed. MTS was shown to be appropriate to investigate the potential of FDG-PET for early breast cancer treatment monitoring; the treatment effect can be observed before a...
Cancer cell international, Jan 14, 2005
Considering the width and importance of using Multicellular Tumor Spheroids (MTS) in oncology res... more Considering the width and importance of using Multicellular Tumor Spheroids (MTS) in oncology research, size determination of MTSs by an accurate and fast method is essential. In the present study an effective, fast and semi-automated method, SASDM, was developed to determinate the size of MTSs. The method was applied and tested in MTSs of three different cell-lines. Frozen section autoradiography and Hemotoxylin Eosin (H&E) staining was used for further confirmation. SASDM was shown to be effective, user-friendly, and time efficient, and to be more precise than the traditional methods and it was applicable for MTSs of different cell-lines. Furthermore, the results of image analysis showed high correspondence to the results of autoradiography and staining. The combination of assessment of metabolic condition and image analysis in MTSs provides a good model to evaluate the effect of various anti-cancer treatments.
American journal of nuclear medicine and molecular imaging, 2012
The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorecta... more The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorectal cancer with trivalent bispecific antibody TF2 and two hapten molecules, [(67/68)Ga]Ga-IMP461 and [(67/68)Ga]Ga-IMP485 by means of pretargeting. Colorectal cancer tissue samples obtained from surgery at Uppsala University Hospital, were frozen fresh and cryosectioned. The two hapten molecules comprising 1,4,7-triazacyclononanetriacetic acid chelate moiety (NOTA) were labeled with (67)Ga or (68)Ga. The autoradiography was conducted by incubating the tissue samples with the bispecific antibody TF2, followed by washing and incubation with one of the radiolabeled hapten molecules. After washing, drying and exposure to phosphor imager plates, the autoradiograms were analyzed and compared to standard histochemistry (hematoxylin-eosin). Pronounced binding was found in the tissue from colorectal cancer using the bispecific antibody TF2 and either of the haptens [(67/68)Ga]Ga-IMP461 and [(67/68)...
Progress in Neuro-Psychopharmacology and Biological Psychiatry, 2002
Anabolic-androgenic steroids (AAS) have recently been shown to induce neurochemical alterations i... more Anabolic-androgenic steroids (AAS) have recently been shown to induce neurochemical alterations in areas of the male rat CNS related to behavioural changes that have been observed among AAS misusers. In the present study, positron emission tomography (PET) is suggested as a suitable in vivo method in order to visualize the density of the dopamine transporter ([ 11 C]-FE-b-CIT) as well as the dopamine D 1-like ([ 11 C]-(+)-SCH23390) and the D 2-like receptors ([ 11 C]-raclopride) in the male rat brain. Chronic treatment with the AAS nandrolone decanoate (15 mg/kg/day for 14 days) caused an up-regulation of the binding potential of the dopamine transporter in the striatum.