| 1. |
- Einarsdottir, Berglind Osk, 1979, et al.
(författare)
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Melanoma patient-derived xenografts accurately model the disease and develop fast enough to guide treatment decisions.
- 2014
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Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 5:20, s. 9609-18
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Tidskriftsartikel (refereegranskat)abstract
- The development of novel therapies against melanoma would benefit from individualized tumor models to ensure the rapid and accurate identification of biomarkers of therapy response. Previous studies have suggested that patient-derived xenografts (PDXes) could be useful. However, the utility of PDXes in guiding real-time treatment decisions has only been reported in anecdotal forms. Here tumor biopsies from patients with stage III and IV metastatic malignant melanoma were transplanted into immunocompromised mice to generate PDXes. 23/26 melanoma biopsies generated serially transplantable PDX models, and their histology, mutation status and expression profile resembled their corresponding patient biopsy. The potential treatment for one patient was revealed by an in vitro drug screen and treating PDXes with the MEK inhibitor trametinib. In another patient, the BRAF mutation predicted the response of both the patient and its corresponding PDXes to MAPK-targeted therapy. Importantly, in this unselected group of patients, the time from biopsy for generation of PDXes until death was significantly longer than the time required to reach the treatment phase of the PDXes. Thus, it could be clinically meaningful to use this type of platform for melanoma patients as a pre-selection tool in clinical trials.
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| 2. |
- Forsberg, Elin, et al.
(författare)
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HER2 CAR-T Cells Eradicate Uveal Melanoma and T-cell Therapy-Resistant Human Melanoma in IL2 Transgenic NOD/SCID IL2 Receptor Knockout Mice
- 2019
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Ingår i: Cancer Research. - 0008-5472. ; 79:5, s. 899-904
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Tidskriftsartikel (refereegranskat)abstract
- Chimeric antigen receptors (CAR) can transmit signals akin to those from activated T-cell receptors when bound to a cell surface target. CAR-expressing T cells against CD19 can cause curative effects in leukemia and lymphoma and is approved for clinical use. However, no CAR-T therapy is currently approved for use in solid tumors. We hypothesize that the resistance of solid tumors to CAR-T can be overcome by similar means as those used to reactivate tumor-infiltrating T lymphocytes (TIL), for example, by cytokines or immune checkpoint blockade. Here we demonstrate that CAR-T cells directed against HER2 can kill uveal and cutaneous melanoma cells in vitro and in vivo. Curative effects in vivo were only observed in xenografts grown in a NOD/SCID IL2 receptor gamma (NOG) knockout mouse strain transgenic for human IL2. The effect was target-specific, as CRISPR/Cas9-mediated disruption of HER2 in the melanoma cells abrogated the killing effect of the CAR-T cells. The CAR-T cells were also able to kill melanoma cells from patients resistant to adoptive T-cell transfer (ACT) of autologous TILs. Thus, CAR-T therapy represents an option for patients that do not respond to immunotherapy with ACT of TIL or immune checkpoint blockade. In addition, our data highlight the use of IL2 transgenic NOG mice as models to prove efficacy of CAR-T-cell products, possibly even in a personalized manner. Significance: These findings demonstrate that a novel humanized mouse model can help clinical translation of CAR-T cells against uveal and cutaneous melanoma that do not respond to TIL therapy or immune checkpoint blockade.
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| 3. |
- Hofving, Tobias, 1989, et al.
(författare)
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The Microenvironment of Small Intestinal Neuroendocrine Tumours Contains Lymphocytes Capable of Recognition and Activation after Expansion
- 2021
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Ingår i: Cancers. - : MDPI AG. - 2072-6694. ; 13:17
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Tidskriftsartikel (refereegranskat)abstract
- Simple Summary The body's immune system can recognize tumors because they often contain proteins that are either different from or more abundant than in normal cells. Here, we characterised the immune cells of a rare tumor type called small-intestinal neuroendocrine tumors (SINET). We find that so called tumour-infiltrating lymphocytes (TILs) can be grown in the laboratory and activated by challenging them with digested tumor. This study provides insights into the largely unknown SINET immune landscape and reveals the anti-tumour reactivity of TILs, which might merit adoptive T cell transfer as a feasible treatment option for patients with SINET. Traditionally, immune evasion and immunotherapy have been studied in cancers with a high mutational load such as melanoma or lung cancer. In contrast, small intestinal neuroendocrine tumours (SINETs) present a low frequency of somatic mutations and are described as genetically stable tumours, rendering immunotherapies largely unchartered waters for SINET patients. SINETs frequently metastasise to the regional lymph nodes and liver at the time of diagnosis, and no curative treatments are currently available for patients with disseminated disease. Here, we characterised the immune landscape of SINET and demonstrated that tumour-infiltrating lymphocytes (TILs) can be expanded and activated during autologous tumour challenge. The composition of lymphocyte subsets was determined by immunophenotyping of the SINET microenvironment in one hepatic and six lymph node metastases. TILs from these metastases were successfully grown out, enabling immunophenotyping and assessment of PD-1 expression. Expansion of the TILs and exposure to autologous tumour cells in vitro resulted in increased T lymphocyte degranulation. This study provides insights into the largely unknown SINET immune landscape and reveals the anti-tumour reactivity of TILs, which might merit adoptive T cell transfer as a feasible treatment option for patients with SINET.
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| 4. |
- Sjölund, Katarina, et al.
(författare)
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Downsizing treatment with tyrosine kinase inhibitors in patients with advanced gastrointestinal stromal tumors improved resectability.
- 2010
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Ingår i: World journal of surgery. - : Springer Science and Business Media LLC. - 1432-2323 .- 0364-2313. ; 34:9, s. 2090-2097
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Gastrointestinal stromal tumors (GISTs) express the receptor tyrosine kinase KIT. Most GISTs have mutations in the KIT or PDGFRA gene, causing activation of tyrosine kinase. Imatinib, a tyrosine kinase inhibitor (TKI), is the first-line palliative treatment for advanced GISTs. Sunitinib was introduced for patients with mutations not responsive to imatinib. The aim was to compare the survival of patients with high-risk resected GISTs treated with TKI prior to surgery with historical controls and to determine if organ-preserving surgery was facilitated. METHODS: Ten high-risk GIST-patients had downsizing/adjuvant TKI treatment: nine with imatinib and one with sunitinib. The patients were matched with historical controls (n = 89) treated with surgery alone, from our population-based series (n = 259). Mutational analysis of KIT and PDGFRA was performed in all cases. The progression-free survival was calculated. RESULTS: The primary tumors decreased in mean diameter from 20.4 cm to 10.5 cm on downsizing imatinib. Four patients with R0 resection and a period of adjuvant imatinib had no recurrences versus 67% in the historical control group. Four patients with residual liver metastases have stable disease on continuous imatinib treatment after surgery. One patient has undergone reoperation with liver resection. The downsizing treatment led to organ-preserving surgery in nine patients and improved preoperative nutritional status in one patient. CONCLUSIONS: Downsizing TKI is recommended for patients with bulky tumors with invasion of adjacent organs. Sunitinib can be used for patients in case of imatinib resistance (e.g., wild-type GISTs), underlining the importance of mutational analysis for optimal surgical planning.
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| 5. |
- Ahlman, Håkan, 1947, et al.
(författare)
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Aspects on diagnosis and treatment of the foregut carcinoid syndrome.
- 1992
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Ingår i: Scandinavian journal of gastroenterology. - 0036-5521. ; 27:6, s. 459-71
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Tidskriftsartikel (refereegranskat)abstract
- Eight patients with the foregut carcinoid syndrome (two gastric and six bronchial primary tumors) are reported. The patients presented with complex clinical symptoms including ectopic production of adrenocorticotrophic hormone and growth hormone-releasing factors. The most alarming symptoms were facial flush and edema, accompanied by severe bronchoconstriction, which easily was misinterpreted as asthmatic attacks. Conventional bronchodilatory drugs may be potentially dangerous in these patients, in whom combined blockade of histamine receptors and treatment with cortisone and octreotide are recommended. Owing to the patients' age and general condition individualized long-term therapy was instituted. Surgical therapy under optimal protection by drugs can be of substantial value also in patients with advanced disease. One patient with life-threatening hormonal symptoms underwent hyperthermic perfusion of the liver with cytotoxic drugs, resulting in good palliation.
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| 6. |
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| 7. |
- Arne, Gabriella, et al.
(författare)
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Expression profiling of GIST: CD133 is associated with KIT exon 11 mutations, gastric location, and poor prognosis.
- 2011
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Ingår i: International journal of cancer. Journal international du cancer. - : Wiley. - 1097-0215 .- 0020-7136. ; 129:5, s. 1149-1161
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Tidskriftsartikel (refereegranskat)abstract
- In gastrointestinal stromal tumors (GISTs), KIT exon 11 deletions are associated with poor prognosis. The aim of this study was to determine the gene expression profiles of GISTs carrying KIT exon 11 deletions and to identify genes associated with poor prognosis. Expression profiling was performed on 9 tumors with KIT exon 11 deletions and 7 without KIT exon 11 mutations using oligonucleotide microarrays. In addition, gene expression profiles for 35 GISTs were analyzed by meta-analysis. Expression of CD133 (prominin-1) protein was examined by tissue microarray (TMA) analysis of 204 GISTs from a population-based study in western Sweden. Survival analysis was performed on patients subjected to R0 resection (n=180) using the Cox proportional hazards model. Gene expression profiling, meta-analysis, and qPCR showed up regulation of CD133 in GISTs carrying KIT exon 11 deletions. Immunohistochemical analysis on TMA confirmed CD133 expression in 28% of all tumors. CD133 positivity was more frequent in gastric GISTs (48%) than in small intestinal GISTs (4%). CD133 positivity was also more frequent in GISTs with KIT exon 11 mutations (41%) than in tumors with mutations in KIT exon 9, PDGFRA, or wild-type tumors (0-17%). Univariate survival analysis showed a significant correlation between the presence of CD133 protein and shorter overall survival (hazard ratio=2.23, P=0.027). Multivariate analysis showed that CD133 provided additional information on patient survival compared to age, sex, NIH risk group and mutational status. CD133 is expressed in a subset of predominantly gastric GISTs with KIT exon 11 mutations and poor prognosis.
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| 8. |
- Arne, Gabriella, et al.
(författare)
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Gastrointestinal stromal tumors (GISTs) express somatostatin receptors and bind radiolabeled somatostatin analogs.
- 2013
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Ingår i: Acta oncologica (Stockholm, Sweden). - 1651-226X .- 0284-186X. ; 52:4, s. 783-792
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Tidskriftsartikel (refereegranskat)abstract
- Background. Gastrointestinal stromal tumors (GISTs) can be effectively treated with tyrosine kinase inhibitors (TKIs). However, some patients with GIST develop drug resistance, and alternative treatment strategies are therefore needed. The aim of this study was to analyze the expression of somatostatin receptors (SSTR) in GIST as a target for peptide receptor-mediated radiotherapy (PRRT). Material and methods. Expression profiling of SSTR1-5 was performed on biopsies from 34 GISTs (16 gastric tumors, 15 small intestinal tumors, and three rectal tumors). SSTR scintigraphy ((111)In-octreotide) and measurement of (111)In activity in tumor specimens was performed in seven patients. Uptake and internalization of (177)Lu- octreotate was studied in primary cell cultures from two patients. Results. Quantitative PCR analysis showed expression of SSTR1 and SSTR2 in the majority of tumors, while SSTR3-5 were expressed at low levels. Immunohistochemical analysis confirmed the presence of SSTR1 and SSTR2 proteins in all GISTs, and SSTR3-5 in a subset of tumors. Diagnostic imaging by SSTR scintigraphy, using (111)In-octreotide, demonstrated tumor uptake of (111)In in three of six GIST patients. Measurement of (111)In activity in excised tumor specimens from five patients gave tumor-to-blood (T/B) activity ratios of between eight and 96. Tumor cells in primary culture (gastric and small intestinal GIST) specifically bound and internalized (177)Lu when incubated with the therapeutic compound (177)Lu-octreotate for 4-48 hours (p < 0.05). Conclusion. Peptide receptor-mediated radiotherapy via SSTR may provide a novel treatment strategy in carefully selected GIST patients with TKI-resistant tumors.
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| 9. |
- Bümming, Per, 1965, et al.
(författare)
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Can the early reduction of tumour markers predict outcome in surgically treated sporadic medullary thyroid carcinoma?
- 2008
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Ingår i: Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie. - : Springer Science and Business Media LLC. - 1435-2443. ; 393:5, s. 699-703
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND AIMS: Patients with sporadic medullary thyroid carcinoma (MTC) have a variable clinical course. Our aim was to analyse the reduction of tumour markers after thyroidectomy with meticulous dissection and relate it to clinical outcome. MATERIALS AND METHODS: Twenty consecutive patients with palpable sporadic MTC underwent thyroidectomy with central and uni- or bilateral modified radical neck dissection; three were subjected to mediastinal dissection. Basal (b-) and stimulated (s-) calcitonin (CT) and carcinoembryonic antigen (CEA)-levels were measured before and 6-8 weeks after primary surgery, and the reduction of these tumour markers was determined. RESULTS: Median CT (b- and s-) were markedly reduced after surgery (98.5% and 99.1%, respectively), and CEA decreased 11 times. CT (b-) fell >99% in seven patients after surgery; in these and four additional patients, CT (s-) showed a similar reduction. During follow-up (median 52.5 months), two patients (stages IV B and C) died of MTC; they had <95% reduction of CT. Four patients (stage IV A) are alive with verified metastases. Eight patients (one stage III, seven stage IV A) are alive with hypercalcitoninemia. Five stages I-III patients and one stage IV A patient are disease-free. CONCLUSIONS: Thyroidectomy and meticulous dissection caused a pronounced reduction of tumour markers. A postoperative reduction of CT (s-) >/=97% seems to be associated with less aggressive clinical course, while CEA had lower predictive value.
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| 10. |
- Bümming, Per, 1965, et al.
(författare)
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Gastrointestinal stromal tumors regularly express synaptic vesicle proteins: evidence of a neuroendocrine phenotype.
- 2007
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Ingår i: Endocrine-related cancer. - 1351-0088. ; 14:3, s. 853-63
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Tidskriftsartikel (refereegranskat)abstract
- Gastrointestinal stromal tumors (GISTs) are thought to originate from the interstitial cells of Cajal, which share many properties with neurons of the gastrointestinal tract. Recently, we demonstrated expression of the hormone ghrelin in GIST. The aim of the present study was therefore to evaluate a possible neuroendocrine phenotype of GIST. Specimens from 41 GISTs were examined for the expression of 12 different synaptic vesicle proteins. Expression of synaptic-like microvesicle proteins, e.g., Synaptic vesicle protein 2 (SV2), synaptobrevin, synapsin 1, and amphiphysin was demonstrated in a majority of GISTs by immunohistochemistry, western blotting, and quantitative reversetranscriptase PCR. One-third of the tumors also expressed the large dense core vesicle protein vesicular monoamine transporter 1. Presence of microvesicles and dense core vesicles in GIST was confirmed by electron microscopy. The expression of synaptic-like microvesicle proteins in GIST was not related to risk profile or to KIT/platelet derived growth factor alpha (PDGFRA) mutational status. Thus, GISTs regularly express a subset of synaptic-like microvesicle proteins necessary for the regulated secretion of neurotransmitters and hormones. Expression of synaptic-like micro-vesicle proteins, ghrelin and peptide hormone receptors in GIST indicate a neuroendocrine phenotype and suggest novel possibilities to treat therapy-resistant GIST.
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