uu.seUppsala University Publications
Change search
Refine search result
12 1 - 50 of 62
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Alimohammadi, Mohammad
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Björklund, Peyman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Hallgren, Åsa
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Pöntynen, Nora
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Szinnai, Gabor
    Shikama, Noriko
    Keller, Marcel P
    Ekwall, Olov
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Kinkel, Sarah A
    Husebye, Eystein S
    Gustafsson, Jan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Rorsman, Fredrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Peltonen, Leena
    Betterle, Corrado
    Perheentupa, Jaakko
    Åkerström, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Scott, Hamish S
    Holländer, Georg A
    Kämpe, Olle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Autoimmune polyendocrine syndrome type 1 and NALP5, a parathyroid autoantigen2008In: New England Journal of Medicine, ISSN 0028-4793, E-ISSN 1533-4406, Vol. 358, no 10, p. 1018-1028Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Autoimmune polyendocrine syndrome type 1 (APS-1) is a multiorgan autoimmune disorder caused by mutations in AIRE, the autoimmune regulator gene. Though recent studies concerning AIRE deficiency have begun to elucidate the molecular pathogenesis of organ-specific autoimmunity in patients with APS-1, the autoantigen responsible for hypoparathyroidism, a hallmark of APS-1 and its most common autoimmune endocrinopathy, has not yet been identified. METHODS: We performed immunoscreening of a human parathyroid complementary DNA library, using serum samples from patients with APS-1 and hypoparathyroidism, to identify patients with reactivity to the NACHT leucine-rich-repeat protein 5 (NALP5). Subsequently, serum samples from 87 patients with APS-1 and 293 controls, including patients with other autoimmune disorders, were used to determine the frequency and specificity of autoantibodies against NALP5. In addition, the expression of NALP5 was investigated in various tissues. RESULTS: NALP5-specific autoantibodies were detected in 49% of the patients with APS-1 and hypoparathyroidism but were absent in all patients with APS-1 but without hypoparathyroidism, in all patients with other autoimmune endocrine disorders, and in all healthy controls. NALP5 was predominantly expressed in the cytoplasm of parathyroid chief cells. CONCLUSIONS: NALP5 appears to be a tissue-specific autoantigen involved in hypoparathyroidism in patients with APS-1. Autoantibodies against NALP5 appear to be highly specific and may be diagnostic for this prominent component of APS-1.

  • 2.
    Backman, Samuel
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Maharjan, Rajani
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Falk Delgado, Alberto
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Plastic Surgery.
    Crona, Joakim
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Cupisti, Kenko
    Marien Hosp, Dept Surg, Euskirchen, Germany..
    Stålberg, Peter
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Hellman, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Björklund, Peyman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Global DNA Methylation Analysis Identifies Two Discrete clusters of Pheochromocytoma with Distinct Genomic and Genetic Alterations2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, article id 44943Article in journal (Refereed)
    Abstract [en]

    Pheochromocytomas and paragangliomas (PPGLs) are rare and frequently heritable neural-crest derived tumours arising from the adrenal medulla or extra-adrenal chromaffin cells respectively. The majority of PPGL tumours are benign and do not recur with distant metastases. However, a sizeable fraction of these tumours secrete vasoactive catecholamines into the circulation causing a variety of symptoms including hypertension, palpitations and diaphoresis. The genetic landscape of PPGL has been well characterized and more than a dozen genes have been described as recurrently mutated. Recent studies of DNA-methylation have revealed distinct clusters of PPGL that share DNA methylation patterns and driver mutations, as well as identified potential biomarkers for malignancy. However, these findings have not been adequately validated in independent cohorts. In this study we use an array-based genome-wide approach to study the methylome of 39 PPGL and 4 normal adrenal medullae. We identified two distinct clusters of tumours characterized by different methylation patterns and different driver mutations. Moreover, we identify genes that are differentially methylated between tumour subcategories, and between tumours and normal tissue.

    Download full text (pdf)
    fulltext
  • 3.
    Backman, Samuel
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Åkerström, Tobias
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Maharjan, Rajani
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery. Uppsala Univ, Dept Surg Sci, Uppsala, Sweden.
    Cupisti, Kenko
    Marien Hosp, Dept Surg, Euskirchen, Germany.
    Willenberg, Holger S.
    Rostock Univ, Med Ctr, Div Endocrinol & Metab, Rostock, Germany.
    Hellman, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Björklund, Peyman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    RNA Sequencing Provides Novel Insights into the Transcriptome of Aldosterone Producing Adenomas2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, article id 6269Article in journal (Refereed)
    Abstract [en]

    Aldosterone producing adenomas (APAs) occur in the adrenal glands of around 30% of patients with primary aldosteronism, the most common form of secondary hypertension. Somatic mutations in KCNJ5, ATP1A1, ATP2B3, CACNA1D and CTNNB1 have been described in similar to 60% of these tumours. We subjected 15 aldosterone producing adenomas (13 with known mutations and two without) to RNA Sequencing and Whole Genome Sequencing (n = 2). All known mutations were detected in the RNA-Seq reads, and mutations in ATP2B3 (G123R) and CACNA1D (S410L) were discovered in the tumours without known mutations. Adenomas with CTNNB1 mutations showed a large number of differentially expressed genes (1360 compared to 106 and 75 for KCNJ5 and ATP1A1/ATP2B3 respectively) and clustered together in a hierarchical clustering analysis. RT-PCR in an extended cohort of 49 APAs confirmed higher expression of AFF3 and ISM1 in APAs with CTNNB1 mutations. Investigation of the expression of genes involved in proliferation and apoptosis revealed subtle differences between tumours with and without CTNNB1 mutations. Together our results consolidate the notion that CTNNB1 mutations characterize a distinct subgroup of APAs.

    Download full text (pdf)
    FULLTEXT01
  • 4.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Backman, Samuel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Epigenetics of pheochromocytoma and paraganglioma2018In: Molecular and Cellular Endocrinology, ISSN 0303-7207, E-ISSN 1872-8057, Vol. 469, p. 92-97Article in journal (Refereed)
    Abstract [en]

    Pheochromocytomas and paragangliomas (PPGLs) are neuroendocrine tumors arising in the medullae of the adrenal glands or in paraganglia. The knowledge of the tumor biology of these lesions has increased dramatically during the past two decades and more than a dozen recurrently mutated genes have been identified. Different clusters have been described that share epigenetic signatures. Mutations in the succinate dehydrogenase complex subunit genes play a pivotal role in reprogramming the epigenetic state of these tumors by inhibiting epigenetic regulators such as TET enzymes and histone demethylases. Another subgroup of tumors carries hypomethylated genomes, and overexpression of several microRNAs has been described. While much remains to be investigated regarding the epigenetics of PPGLs, it is clear that it plays an important role in PPGL biology.

  • 5.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Cupisti, Kenko
    Fryknäs, Mårten
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Pharmacology.
    Isaksson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Willenberg, H. S.
    Åkerström, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Hellman, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Stathmin as a Marker for Malignancy in Pheochromocytomas2010In: Experimental and clinical endocrinology & diabetes, ISSN 0947-7349, E-ISSN 1439-3646, Vol. 118, no 1, p. 27-30Article in journal (Refereed)
    Abstract [en]

    Pheochromocytomas of the adrenal medulla may be life-threatening catecholamine-producing tumors which are malignant in about 10% of cases. Differential diagnosis between malignant and benign tumors is dependent on the development of metastasis or extensive local invasion. A number of genetic aberrations have been described in pheochromocytomas, but no marker associated to malignancy has been reported. We applied an expression microarray containing 7770 cDNA clones and analysed the expression profiles in eleven tumors compared to normal adrenal medulla. Stathmin (STMN1, Op18) was most conspiciously overexpressed among the differentially expressed genes. RT-PCR analysis further confirmed mRNA overexpression, 6 to 8-fold for benign and malignant tumors, and 16-fold for metastases. Stathmin protein overexpression was observed by immunohistochemistry, and distinct differential protein expression between benign and malignant/metastasis specimens was confirmed by Western blot analysis. The results introduce stathmin as a possible diagnostic marker for malignant pheochromocytomas, and further evaluations are warranted.

  • 6.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Hellman, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Culture of Parathyroid Cells2012In: Human Cell Culture Protocols: Third edition / [ed] Ragai R. Mitry and Robin D. Hughes, Springer, 2012, p. 43-53Chapter in book (Refereed)
    Abstract [en]

    The parathyroid cells are highly differentiated with more or less their only function to secrete parathyroid hormone in response to the extracellular calcium level. Tumours from the parathyroid glands are >99% benign, and have a slow proliferation rate. Culture of parathyroid cells is known to be very difficult most likely due to the high differentiation level. This chapter reveals some details in order how to get parathyroid cells to survive in culture after dispersion of normal bovine parathyroid glands or pathological human parathyroid tumours. Detailed protocols describing cell dispersion with collagenase, short-term cultures, and establishment of long-term cultures are presented.

  • 7.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Krajisnik, Tijana
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Internal Medicine.
    Åkerström, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Larsson, Tobias E.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Internal Medicine.
    Type I membrane Klotho expression is decreased and inversely correlated to serum calcium in primary hyperparathyroidism2008In: Journal of Clinical Endocrinology and Metabolism, ISSN 0021-972X, E-ISSN 1945-7197, Vol. 93, no 10, p. 4152-4157Article in journal (Refereed)
    Abstract [en]

    Context: The type I membrane protein Klotho was recently shownto mediate PTH secretion in parathyroid cells in response tolow extracellular calcium. In contrast, Klotho inhibits PTHsecretion indirectly through the action of fibroblast growthfactor-23. Abnormal Klotho expression in parathyroid disordersremains to be elucidated.

    Objective: The aim of the study was to determine: 1) Klothoexpression in parathyroid adenomas from patients with primaryhyperparathyroidism (pHPT) compared to normal tissue; and 2)its relation to the serum calcium and PTH levels.

    Design: Surgically removed parathyroid glands (n = 40) and fournormal parathyroid tissue specimens were analyzed for KlothomRNA and protein levels by quantitative real-time PCR and immunohistochemistry.In vitro effects of calcium on Klotho mRNA expression were studiedin bovine parathyroid cells.

    Results: Klotho mRNA levels were significantly decreased (n= 23) or undetectable (n = 17) in parathyroid adenomas comparedto normal tissues (P < 0.001). Reduced Klotho protein expressionwas confirmed by immunohistochemistry. Klotho mRNA levels wereinversely correlated to serum calcium (r = –0.97; P <0.0001), and calcium dose-dependently decreased Klotho mRNAexpression in normal parathyroid cells in vitro (P < 0.01).Serum calcium was the only significant marker of Klotho expressionin multivariate analysis with calcium, phosphate, PTH, and adenomaweight as independent variables.

    Conclusions: Parathyroid Klotho expression is decreased or undetectablein pHPT. We provide evidence that 1) serum calcium is stronglyassociated with parathyroid Klotho expression in pHPT; and 2)abnormal PTH secretion in hypercalcemic pHPT subjects is mediatedby Klotho-independent mechanisms.

  • 8.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Lindberg, Daniel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Åkerström, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Stabilizing mutation of CTNNB1/beta-catenin and protein accumulation analyzed in a large series of parathyroid tumors of Swedish patients2008In: Molecular Cancer, ISSN 1476-4598, E-ISSN 1476-4598, Vol. 7, p. 53-Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Aberrant accumulation of beta-catenin plays an important role in a variety of human neoplasms. We recently reported accumulation of beta-catenin in parathyroid adenomas from patients with primary hyperparathyroidism (pHPT). In CTNNB1 exon 3, we detected a stabilizing mutation (S37A) in 3 out of 20 analyzed adenomas. The aim of the present study was to determine the frequency and zygosity of mutations in CTNNB1 exon 3, and beta-catenin accumulation in a large series of parathyroid adenomas of Swedish patients. RESULTS: The mutation S37A (TCT > GCT) was detected by direct DNA sequencing of PCR fragments in 6 out of 104 sporadic parathyroid adenomas (5.8%). Taking our previous study into account, a total of 9 out of 124 (7.3%) adenomas displayed the same mutation. The mutations were homozygous by DNA sequencing, restriction enzyme cleavage, and gene copy number determination using the GeneChip 500 K Mapping Array Set. All tumors analyzed by immunohistochemistry, including those with mutation, displayed aberrant beta-catenin accumulation. Western blotting revealed a slightly higher expression level of beta-catenin and nonphosphorylated active beta-catenin in tumors with mutation compared to those without. Presence of the mutation was not related to distinct clinical characteristics. CONCLUSION: Aberrant accumulation of beta-catenin is very common in parathyroid tumors, and is caused by stabilizing homozygous mutation in 7.3% of Swedish pHPT patients.

  • 9.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Pacak, K.
    NIH, Eunice Kennedy Shriver Natl Inst Child Hlth & Hum, Sect Med Neuroendocrinol Program Reprod & Adult E, Bethesda, MD USA..
    Crona, Joakim
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Precision medicine in pheochromocytoma and paraganglioma: current and future concepts2016In: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 286, no 6, p. 559-573Article in journal (Refereed)
    Abstract [en]

    Pheochromocytoma and paraganglioma (PPGL) are rare diseases but are also amongst the most characterized tumour types. Hence, patients with PPGL have greatly benefited from precision medicine for more than two decades. According to current molecular biology and genetics-based taxonomy, PPGL can be divided into three different clusters characterized by: Krebs cycle reprogramming with oncometabolite accumulation or depletion (group 1a); activation of the (pseudo)hypoxia signalling pathway with increased tumour cell proliferation, invasiveness and migration (group 1b); and aberrant kinase signalling causing a pro-mitogenic and anti-apoptotic state (group 2). Categorization into these clusters is highly dependent on mutation subtypes. At least 12 different syndromes with distinct genetic causes, phenotypes and outcomes have been described. Genetic screening tests have a documented benefit, as different PPGL syndromes require specific approaches for optimal diagnosis and localization of various syndrome-related tumours. Genotype-tailored treatment options, follow-up and preventive care are being investigated. Future new developments in precision medicine for PPGL will mainly focus on further identification of driver mechanisms behind both disease initiation and malignant progression. Identification of novel druggable targets and prospective validation of treatment options are eagerly awaited. To achieve these goals, we predict that collaborative large-scale studies will be needed: Pheochromocytoma may provide an example for developing precision medicine in orphan diseases that could ultimately aid in similar efforts for other rare conditions.

  • 10.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Starker, Lee F
    Department of Surgery, Yale University School of Medicine, New Haven, CT, USA.
    Fonseca, A
    Carling, T
    Molecular Basis of Primary Hyperparathyroidism2010In: World Journal of Endocrine Surgery, ISSN 0975-5039, Vol. 2, no 2, p. 63-70Article in journal (Other academic)
    Abstract [en]

    During the past decade and a half, studies of genetic predisposition, parathyroid tumorigenesis, and molecular genetics of familialhyperparathyroid disorders have started to unveil the molecular basis of pHPT. Primary HPT is found in several distinct disorders withautosomal dominant inheritance such as in multiple endocrine neoplasia type 1 (MEN1), MEN2A, the HPT-jaw tumor syndrome (HPT-JT),familial isolated hyperparathyroidism (FIHPT), autosomal dominant mild hyperparathyroidism (ADMH), and neonatal severe HPT (NSHPT).

  • 11.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Svedlund, Jessica
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Olsson, Anna-Karin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Åkerström, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    The internally truncated LRP5 receptor presents a therapeutic target in breast cancer2009In: PloS one, ISSN 1932-6203, Vol. 4, no 1, p. e4243-Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Breast cancer is a common malignant disease, which may be caused by a number of genes deregulated by genomic or epigenomic events. Deregulated WNT/beta-catenin signaling with accumulation of beta-catenin is common in breast tumors, but mutations in WNT signaling pathway components have been rare. An aberrantly spliced internally truncated LRP5 receptor (LRP5Delta666-809, LRP5Delta) was shown recently to be resistant to DKK1 inhibition, and was required for beta-catenin accumulation in hyperparathyroid tumors and parathyroid tumor growth. METHODOLOGY/PRINCIPAL FINDINGS: Here we show, by reverse transcription PCR and Western blot analysis, that LRP5Delta is frequently expressed in breast tumors of different cancer stage (58-100%), including carcinoma in situ and metastatic carcinoma. LRP5Delta was required in MCF7 breast cancer cells for the non-phosphorylated active beta-catenin level, transcription activity of beta-catenin, cell growth in vitro, and breast tumor growth in a xenograft SCID mouse model. WNT3 ligand, but not WNT1 and WNT3A augmented the endogenous beta-catenin activity of MCF7 cells in a DKK1-insensitive manner. Furthermore, an anti-LRP5 antibody attenuated beta-catenin activity, inhibited cell growth, and induced apoptosis in LRP5Delta-positive MCF7 and T-47D breast cancer cells, but not in control cells. CONCLUSIONS/SIGNIFICANCE: Our results suggest that the LRP5Delta receptor is strongly implicated in mammary gland tumorigenesis and that its aberrant expression present an early event during disease progression. LRP5 antibody therapy may have a significant role in the treatment of breast cancer.

  • 12.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Åkerström, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    A LRP5 receptor with internal deletion in hyperparathyroid tumors with implications for deregulated Wnt/β-catenin signaling2007In: PLoS Medicine, ISSN 1549-1277, E-ISSN 1549-1676, Vol. 4, no 11, p. 1829-1841Article in journal (Refereed)
    Abstract [en]

    Background Hyperparathyroidism (HPT) is a common endocrine disorder with incompletely understood etiology, characterized by enlarged hyperactive parathyroid glands and increased serum concentrations of parathyroid hormone and ionized calcium. We have recently reported activation of the Wnt signaling pathway by accumulation of beta-catenin in all analyzed parathyroid tumors from patients with primary HPT (pHPT) and in hyperplastic parathyroid glands from patients with uremia secondary to HPT (sHPT). Mechanisms that may account for this activation have not been identified, except for a few cases of beta-catenin (CTNNB1) stabilizing mutation in pHPT tumors. Methods and Findings Reverse transcription PCR and Western blot analysis showed expression of an aberrantly spliced internally truncated WNT coreceptor low-density lipoprotein receptor-related protein 5 (LRP5) in 32 out of 37 pHPT tumors (86%) and 20 out of 20 sHPT tumors (100%). Stabilizing mutation of CTNNB1 and expression of the internally truncated LRP5 receptor was mutually exclusive. Expression of the truncated LRP5 receptor was required to maintain the nonphosphorylated active beta-catenin level, transcription activity of beta-catenin, MYC expression, parathyroid cell growth in vitro, and parathyroid tumor growth in a xenograft severe combined immunodeficiency ( SCID) mouse model. WNT3 ligand and the internally truncated LRP5 receptor strongly activated transcription, and the internally truncated LRP5 receptor was insensitive to inhibition by DKK1. Conclusions The internally truncated LRP5 receptor is strongly implicated in deregulated activation of the WNT/beta-catenin signaling pathway in hyperparathyroid tumors, and presents a potential target for therapeutic intervention.

  • 13.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Åkerström, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Accumulation of nonphosphorylated β-catenin and c-myc in primary and uremic secondary hyperparathyroid tumors2007In: Journal of Clinical Endocrinology and Metabolism, ISSN 0021-972X, E-ISSN 1945-7197, Vol. 92, no 1, p. 338-344Article in journal (Refereed)
    Abstract [en]

    CONTEXT: Primary hyperparathyroidism (pHPT) resulting from parathyroid tumors is a common endocrine disorder with incompletely understood etiology, affecting about 1% of the adult population, with an even higher prevalence for elderly individuals. In renal failure, secondary hyperparathyroidism (sHPT) occurs with multiple tumor development as a result of calcium and vitamin D regulatory disturbance. OBJECTIVE: Aberrant Wnt/beta-catenin signaling with accumulation of beta-catenin in the cytoplasm/nucleus is involved in the development of a variety of neoplasms. The aim of this study was to evaluate whether the Wnt/beta-catenin signaling pathway is activated in parathyroid adenomas of pHPT and in hyperplastic glands from uremic patients with sHPT. DESIGN: Immunohistochemistry, Western blotting, real-time quantitative RT-PCR, and DNA sequencing were performed. RESULTS: beta-Catenin was accumulated in all analyzed parathyroid tumors (n = 47) from patients with pHPT and from patients with HPT secondary to uremia. The accumulation included nonphosphorylated, stabilized (transcriptionally active) beta-catenin. The overexpression was not related to increased beta-catenin mRNA levels. A protein-stabilizing mutation in exon 3 of beta-catenin (S37A) was detected in three of 20 pHPT tumors (15%). No mutation was detected in secondary hyperplastic glands (n = 20), and no evidence for truncated adenomatosis polyposis coli proteins was found in adenomas and secondary hyperplastic glands. Mutations in other Wnt signaling components leading to beta-catenin accumulation, other than in beta-catenin itself, are therefore anticipated. The beta-catenin target gene c-myc was overexpressed in a substantial fraction of the parathyroid tumors. CONCLUSION: Our results strongly suggest that modifications in the Wnt/beta-catenin signaling pathway may be involved in the development of hyperparathyroidism.

  • 14.
    Björklund, Peyman
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Åkerström, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Activated β-catenin in the novel human parathyroid tumor cell line sHPT-12007In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 352, no 2, p. 532-536Article in journal (Refereed)
    Abstract [en]

    Misregulation of the Wnt/beta-catenin signalling pathway is involved in the development and progression of many cancers. Recently, we presented evidence for aberrant accumulation of non-phosphorylated (stabilized) beta-catenin in benign parathyroid tumors from patients with primary hyperparathyroidism (pHPT) or HPT secondary to uremia (sHPT). Here we have used a human parathyroid hormone (PTH)-producing cell line (sHPT-1), established from a hyperplastic parathyroid gland removed at operation of a patient with sHPT, to further investigate the potential importance of beta-catenin in parathyroid tumorigenesis. Our studies demonstrate that efficient and specific knockdown of beta-catenin by small interfering RNA (siRNA) markedly decreased endogenous beta-catenin transcriptional activity as well as expression of the Wnt/beta-catenin target genes cyclin D1 and c-myc, known to be overexpressed in a substantial fraction of parathyroid tumors. Furthermore, siRNA to beta-catenin inhibited cellular growth and induced cell death. Growth and survival of the parathyroid tumor cells are thus dependent on maintained expression level of beta-catenin. The Wnt/beta-catenin signalling pathway, and beta-catenin in particular, presents a potential therapeutic target for HPT.

  • 15. Choi, Murim
    et al.
    Scholl, Ute I.
    Yue, Peng
    Björklund, Peyman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Zhao, Bixiao
    Nelson-Williams, Carol
    Ji, Weizhen
    Cho, Yoonsang
    Patel, Aniruddh
    Men, Clara J.
    Lolis, Elias
    Wisgerhof, Max V.
    Geller, David S.
    Mane, Shrikant
    Hellman, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Åkerström, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Wang, Wenhui
    Carling, Tobias
    Lifton, Richard P.
    K+ Channel Mutations in Adrenal Aldosterone-Producing Adenomas and Hereditary Hypertension2011In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 331, no 6018, p. 768-772Article in journal (Refereed)
    Abstract [en]

    Endocrine tumors such as aldosterone-producing adrenal adenomas (APAs), a cause of severe hypertension, feature constitutive hormone production and unrestrained cell proliferation; the mechanisms linking these events are unknown. We identify two recurrent somatic mutations in and near the selectivity filter of the potassium (K+) channel KCNJ5 that are present in 8 of 22 human APAs studied. Both produce increased sodium (Na+) conductance and cell depolarization, which in adrenal glomerulosa cells produces calcium (Ca2+) entry, the signal for aldosterone production and cell proliferation. Similarly, we identify an inherited KCNJ5 mutation that produces increased Na+ conductance in a Mendelian form of severe aldosteronism and massive bilateral adrenal hyperplasia. These findings explain pathogenesis in a subset of patients with severe hypertension and implicate loss of K+ channel selectivity in constitutive cell proliferation and hormone production.

  • 16. Cromer, M. Kyle
    et al.
    Choi, Murim
    Nelson-Williams, Carol
    Fonseca, Annabelle L.
    Kunstman, John W.
    Korah, Reju M.
    Overton, John D.
    Mane, Shrikant
    Kenney, Barton
    Malchoff, Carl D.
    Stålberg, Peter
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Åkerström, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Hellman, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Carling, Tobias
    Björklund, Peyman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Lifton, Richard P.
    Neomorphic effects of recurrent somatic mutations in Yin Yang 1 in insulin-producing adenomas2015In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 112, no 13, p. 4062-4067Article in journal (Refereed)
    Abstract [en]

    Insulinomas are pancreatic islet tumors that inappropriately secrete insulin, producing hypoglycemia. Exome and targeted sequencing revealed that 14 of 43 insulinomas harbored the identical somatic mutation in the DNA-binding zinc finger of the transcription factor Yin Yang 1 (YY1). Chromatin immunoprecipitation sequencing (ChIP-Seq) showed that this T372R substitution changes the DNA motif bound by YY1. Global analysis of gene expression demonstrated distinct clustering of tumors with and without YY1(T372R) mutations. Genes showing large increases in expression in YY1(T372R) tumors included ADCY1 (an adenylyl cyclase) and CACNA2D2 (a Ca2+ channel); both are expressed at very low levels in normal beta-cells and show mutation-specific YY1 binding sites. Both gene products are involved in key pathways regulating insulin secretion. Expression of these genes in rat INS-1 cells demonstrated markedly increased insulin secretion. These findings indicate that YY1(T372R) mutations are neomorphic, resulting in constitutive activation of cAMP and Ca2+ signaling pathways involved in insulin secretion.

  • 17.
    Crona, Joakim
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Backman, Samuel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Kugelberg, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Maharjan, Rajani
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Björklund, Peyman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Hellman, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Multiregion Analysis Reveal Evolutionary Patterns and a Chromosomal Instability Signature in Pancreatic Neuroendocrine Tumours2016Conference paper (Refereed)
  • 18.
    Crona, Joakim
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Backman, Samuel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Maharjan, Rajani
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Mayrhofer, Markus
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cancer Pharmacology and Computational Medicine.
    Stålberg, Peter
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Isaksson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cancer Pharmacology and Computational Medicine.
    Hellman, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Björklund, Peyman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Spatiotemporal Heterogeneity Characterizes the Genetic Landscape of Pheochromocytoma and Defines Early Events in Tumorigenesis.2015In: Clinical Cancer Research, ISSN 1078-0432, E-ISSN 1557-3265, Vol. 21, no 19, p. 4451-4460Article in journal (Refereed)
    Abstract [en]

    PURPOSE: Pheochromocytoma and paraganglioma (PPGL) patients display heterogeneity in the clinical presentation and underlying genetic cause. The degree of inter- and intratumor genetic heterogeneity has not yet been defined.

    EXPERIMENTAL DESIGN: In PPGLs from 94 patients, we analyzed LOH, copy-number variations, and mutation status of SDHA, SDHB, SDHC, SDHD, SDHAF2, VHL, EPAS1, NF1, RET, TMEM127, MAX, and HRAS using high-density SNP array and targeted deep sequencing, respectively. Genetic heterogeneity was determined through (i) bioinformatics analysis of individual samples that estimated absolute purity and ploidy from SNP array data and (ii) comparison of paired tumor samples that allowed reconstruction of phylogenetic trees.

    RESULTS: Mutations were found in 61% of the tumors and correlated with specific patterns of somatic copy-number aberrations (SCNA) and degree of nontumoral cell admixture. Intratumor genetic heterogeneity was observed in 74 of 136 samples using absolute bioinformatics estimations and in 22 of 24 patients by comparison of paired samples. In addition, a low genetic concordance was observed between paired primary tumors and distant metastases. This allowed for reconstructing the life history of individual tumors, identifying somatic mutations as well as copy-number loss of 3p and 11p (VHL subgroup), 1p (Cluster 2), and 17q (NF1 subgroup) as early events in PPGL tumorigenesis.

    CONCLUSIONS: Genomic landscapes of PPGL are specific to mutation subtype and characterized by genetic heterogeneity both within and between tumor lesions of the same patient.

  • 19.
    Crona, Joakim
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Björklund, Peyman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Welin, Staffan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Oncology.
    Kozlovacki, Gordana
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Oncology.
    Öberg, Kjell
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Oncology.
    Granberg, Dan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Oncology.
    Treatment, prognostic markers and survival in thymic neuroendocrine tumours: A study from a single tertiary referral centre2013In: Lung Cancer, ISSN 0169-5002, E-ISSN 1872-8332, Vol. 79, no 3, p. 289-293Article in journal (Refereed)
    Abstract [en]

    Thymic neuroendocrine tumours (TNETs) are uncommon but malignant neoplasms, usually associated with a poor prognosis. The number of cases reported is limited to a few hundreds and there are few prognostic factors available. All 28 patients (22 male, 6 female; median age 46.5 years) with thymic neuroendocrine tumour, treated at the Department of Endocrine Oncology, Uppsala University Hospital, Uppsala, Sweden between 1985 and 2011 were studied. The overall 3, 5 and 10-year survival was 89%, 79% and 41% respectively. Ki67<10% (p=0.018) as well as surgical resection (p=0.001) and macroscopically radical primary surgery (p=0.034) was associated with increased survival. Staging & grading according to Masaoka and ENETS systems did not correlate with survival. However, a modified ENETS grading showed a positive correlation (p=0.015). Median time to progression was 20.5 months with Temozolomide and 18 months with platinum based therapy. Partial responses were noted in three patients (38%) treated with platinum based therapy and in two patients (20%) treated with Temozolomide based therapy. High proliferative rate, measured by Ki67 index, and absence of macroscopically radical primary resection as well as no surgical resection are three negative prognostic factors in patients with TNETs. Temozolomide or Platinum based chemotherapy should be considered as first-line medical therapy in patients with metastatic or non-resectable tumours.

  • 20.
    Crona, Joakim
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Experimental Surgery.
    Granberg, Dan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Oncology.
    Norlén, Olov
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Wärnberg, Fredrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Stålberg, Peter
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Hellman, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Björklund, Peyman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Metastases from Neuroendocrine Tumors to the Breast Are More Common than Previously Thought. A Diagnostic Pitfall?2013In: World Journal of Surgery, ISSN 0364-2313, E-ISSN 1432-2323, Vol. 37, no 7, p. 1701-1706Article in journal (Refereed)
    Abstract [en]

    Metastases from neuroendocrine tumors (NETs) to the breast have been described as a rare phenomenon. Presentation, imaging results, and cytopathologic findings of these tumours may closely mimic those of a mammary carcinoma. This study was a retrospective review of 661 patients with metastatic NETs, of whom 280 were females, treated at Uppsala University Hospital, Uppsala, Sweden. Patients with pathological breast lesions were identified. Histopathological slides from available NET breast lesions were analyzed for mammary carcinoma and neuroendocrine markers. We have identified 20 female patients with NET metastases to the breast, 11/235 with small intestinal NETs, 8/55 with lung NETs, and 1/6 with thymic NETs. There were no male patients with NET metastatic to the breast. Four patients had their breast lesion initially diagnosed as mammary carcinoma. Retrospectively, these lesions showed negative staining for mammary carcinoma markers. Metastases to the breast from neuroendocrine tumors may be more common than previously thought. Patients with a lesion to the breast and symptoms typical for NET may benefit from additional histopathological investigation, because NET metastases and mammary carcinoma have different immunohistochemical profiles.

  • 21.
    Crona, Joakim
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Gustavsson, Tobias
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Norlén, Olov
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Edfeldt, Katarina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Åkerström, Tobias
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Westin, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Hellman, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Björklund, Peyman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Stålberg, Peter
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Somatic Mutations and Genetic Heterogeneity at the CDKN1B Locus in Small Intestinal Neuroendocrine Tumors2015In: Annals of Surgical Oncology, ISSN 1068-9265, E-ISSN 1534-4681, Vol. 22, p. 1428-1435Article in journal (Refereed)