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- Crona, Joakim, et al.
(författare)
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Somatic Mutations and Genetic Heterogeneity at the CDKN1B Locus in Small Intestinal Neuroendocrine Tumors
- 2015
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Ingår i: Annals of Surgical Oncology. - : Springer Science and Business Media LLC. - 1068-9265 .- 1534-4681. ; 22, s. 1428-1435
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Until recently, the genetic landscape of small intestinal neuroendocrine tumors (SI-NETs) was limited to recurrent copy number alterations, most commonly a loss on chromosome 18. Intertumor heterogeneity with nonconcordant genotype in paired primary and metastatic lesions also is described, further contributing to the difficulty of unraveling the genetic enigma of SI-NETs. A recent study analyzing 55 SI-NET exomes nominated CDKN1B (p27) as a haploinsufficient tumor suppressor gene.METHODS: This study aimed to determine the frequency of CDKN1B inactivation and to investigate genotype-phenotype correlations. It investigated 362 tumors from 200 patients. All samples were resequenced for mutations in CDKN1B using automated Sanger sequencing. The expression of p27 was investigated in 12 CDKN1B mutant and nine wild type tumors.RESULTS: Some 8.5 % (17/200) of patients had tumors with pathogenic mutations in CDKN1B including 13 insertion deletions, four nonsense variants, and one stop-loss variant. All variants with available nontumoral DNA were classified as somatic. Inter- and intratumor heterogeneity at the CDKN1B locus was detected respectively in six of ten and two of ten patients. Patients with CDKN1B mutated tumors had both heterogeneous disease presentation and diverse prognosis. Expression of the p27 protein did not correlate with CDKN1B mutation status, and no differences in the clinical characteristics between CDKN1B mutated and CDKN1B wild type tumor carriers were found.CONCLUSION: This study corroborates the finding of CDKN1B as a potential haplo-insufficient tumor suppressor gene characterized by inter- and intratumor heterogeneity in SI-NETs.
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| 3. |
- Edfeldt, Katarina, 1979-, et al.
(författare)
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A Plausible Role for Actin Gamma Smooth Muscle 2 (ACTG2) in Small Intestinal Neuroendocrine Tumorgenesis
- 2016
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Ingår i: BMC Endocrine Disorders. - : BioMed Central (BMC). - 1472-6823. ; 16
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Small intestinal neuroendocrine tumors (SI-NETs) originate from the enterochromaffin cells in the ileum and jejunum. The knowledge about genetic and epigenetic abnormalities is limited. Low mRNA expression levels of actin gamma smooth muscle 2 (ACTG2) have been demonstrated in metastases relative to primary SI-NETs. ACTG2 and microRNA-145 (miR-145) are aberrantly expressed in other cancers and ACTG2 can be induced by miR-145. The aim of this study was to investigate the role of ACTG2 in small intestinal neuroendocrine tumorigenesis.METHODS: Protein expression was analyzed in SI-NETs (n = 24) and in enterochromaffin cells by immunohistochemistry. The cell line CNDT2.5 was treated with the histone methyltransferase inhibitor 3-deazaneplanocin A (DZNep), the selective EZH2 inhibitor EPZ-6438, or 5-aza-2'-deoxycytidine, a DNA hypomethylating agent. Cells were transfected with ACTG2 expression plasmid or miR-145. Western blotting analysis, quantitative RT-PCR, colony formation- and viability assays were performed. miR-145 expression levels were measured in tumors.RESULTS: Eight primary tumors and two lymph node metastases displayed variable levels of positive staining. Fourteen SI-NETs and normal enterochromaffin cells stained negatively. Overexpression of ACTG2 significantly inhibited CNDT2.5 cell growth. Treatment with DZNep or transfection with miR-145 induced ACTG2 expression (>10-fold), but no effects were detected after treatment with EPZ-6438 or 5-aza-2'-deoxycytidine. DZNep also induced miR-145 expression. SI-NETs expressed relatively low levels of miR-145, with reduced expression in metastases compared to primary tumors.CONCLUSIONS: ACTG2 is expressed in a fraction of SI-NETs, can inhibit cell growth in vitro, and is positively regulated by miR-145. Theoretical therapeutic strategies based on these results are discussed.
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| 7. |
- Edfeldt, Katarina, 1979-, et al.
(författare)
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DcR3, TFF3 and Midkine are Novel Serum Biomarkers in Small Intestinal Neuroendocrine Tumors
- 2017
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Ingår i: Neuroendocrinology. - : S. Karger AG. - 0028-3835 .- 1423-0194. ; 105:2, s. 170-181
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Tidskriftsartikel (refereegranskat)abstract
- Small intestinal neuroendocrine tumors (SI-NETs) are amine- and peptide producing neoplasms. Most patients display metastases at the time of diagnosis, they have an unpredictable individual disease course and the tumors are often therapy resistant. Chromogranin A (CgA) and 5-hydroxyindoleacetic acid (5-HIAA) are the clinically most used biomarkers today, but there is a great need for novel diagnostic and prognostic biomarkers and new therapeutic targets. Sixty-nine biomarkers were screened in serum from 23 SI-NET patients and 23 healthy controls using multiplex PLA (proximity ligation assay). A refined method, PEA (proximity extension assay), was used to analyze 76 additional biomarkers. Statistical testing and multivariate classification were performed. Immunohistochemistry and ELISA assays were performed in an extended cohort. Using PLA, 19 biomarkers showed a significant difference in serum concentrations between patients and controls, and PEA revealed difference in concentrations in 13 proteins. Multivariate classification analysis revealed decoy receptor 3 (DcR3), trefoil factor 3 (TFF3) and Midkine to be good biomarkers for disease, which was confirmed by ELISA analysis. All three biomarkers were expressed in tumor tissue. DcR3 concentrations were elevated in patients with stage IV disease. High concentrations of DcR3 and TFF3 were correlated to poor survival. DcR3, TFF3 and Midkine exhibited elevated serum concentrations in SI-NET patients compared to healthy controls, and DcR3 and TFF3 were associated with poor survival. DcR3 seems to be a marker for liver metastases while TFF3 and Midkine may be new diagnostic biomarkers for SI-NETs.
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| 8. |
- Edfeldt, Katarina, et al.
(författare)
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Different gene expression profiles in metastasizing midgut carcinoid tumors
- 2011
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Ingår i: Endocrine-Related Cancer. - 1351-0088 .- 1479-6821. ; 18:4, s. 479-489
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Tidskriftsartikel (refereegranskat)abstract
- The genetic events leading the progression of midgut carcinoid tumors are largely unknown. The disease course varies from patient to patient, and there is a lack of reliable prognostic markers. In order to identify genes involved in tumor progression, gene expression profiling was performed on tumor specimens. Samples comprised 18 primary tumors, 17 lymph node (LN) metastases, and seven liver metastases from a total of 19 patients. Patients were grouped according to clinical data and histopathology into indolent or progressive course. RNA was subjected to a spotted oligo microarray and B-statistics were performed. Differentially expressed genes were verified using quantitative real-time PCR. Self-organizing maps demonstrated three clusters: 11 primary tumors separated in one cluster, five LN metastases in another cluster, whereas all seven liver metastases, seven primary, and 12 LN metastases formed a third cluster. There was no correlation between indolent and progressive behavior. The primary tumors with Ki67>5%, with low frequency of the carcinoid syndrome, and a tendency toward shorter survival grouped together. Primary tumors differed in expression profile from their associated LN metastases; thus, there is evidence for genetic changes from primary tumors to metastases. ACTG2, GREM2, REG3A, TUSC2, RUNX1, TPH1, TGFBR2, and CDH6 were differentially expressed between clusters and subgroups of tumors. The expression profile that assembles tumors as being genetically similar on the RNA expression level may not be concordant with the clinical disease course. This study reveals differences in gene expression profiles and novel genes that may be of importance in midgut carcinoid tumor progression.
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| 9. |
- Edfeldt, Katarina, 1979-, et al.
(författare)
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Improved health‐related quality of life during peptide receptor radionuclide therapy in patients with neuroendocrine tumours
- 2023
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Ingår i: Journal of neuroendocrinology. - : John Wiley & Sons. - 0953-8194 .- 1365-2826. ; 35:10
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Tidskriftsartikel (refereegranskat)abstract
- Neuroendocrine tumours (NETs) can arise in different locations in the body, and may give rise to hormonal symptoms, which amongst other factors may affect patients' health-related quality of life (HRQoL). Up to four cycles of peptide receptor radionuclide therapy (PRRT) have been shown effective for symptom alleviation and prolonging progression-free survival. The aim of this study was to assess the patient's perspective regarding changes in their HRQoL during PRRT. HRQoL was assessed using the questionnaires for cancer in general, EORTC QLQ-C30, and the gastrointestinal NET-specifically EORTC QLQ-GINET21. Patients with NET (n = 204) rated their HRQoL before PRRT cycles one and four. The medical records of patients were reviewed and their HRQoL was compared to a matched reference population (n = 4910). HRQoL was found to improve during PRRT in aspects of global quality of life; role, social, and emotional functioning, and multiple symptom relief. Potential risk groups for worse HRQoL during PRRT were patients with overweight (BMI >25) who completed four cycles of PRRT and older patients (>65 years old). In conclusion, we found that PRRT improves HRQoL in patients with NETs. The results of this study may be used to improve person-centred care.
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