| 1. |
- Aljabery, Firas, et al.
(author)
-
Radio-guided sentinel lymph node detection and lymph node mapping in invasive urinary bladder cancer : a prospective clinical study.
- 2017
-
In: BJU International. - : Wiley-Blackwell Publishing Inc.. - 1464-4096 .- 1464-410X. ; 120:3, s. 329-336
-
Journal article (peer-reviewed)abstract
- OBJECTIVES: To investigate the possibility of detecting sentinel lymph nodes (SNs) in patients with urinary bladder cancer (BCa) intra-operatively and whether the histopathological status of the identified SNs reflected that of the lymphatic field.PATIENTS AND METHODS: We studied 103 patients with BCa pathological stage T1-T4 who were treated with cystectomy and pelvic lymph node (LN) dissection during 2005-2011 at the Department of Urology, Linköping University Hospital. Radioactive tracer Nanocoll 70 MBq and blue dye were injected into the bladder wall around the primary tumour before surgery. SNs were detected ex vivo during the operation with a handheld Geiger probe (Gamma Detection System; Neoprobe Corp., Dublin, OH, USA). All LNs were formalin-fixed, sectioned three times, mounted on slides and stained with haematoxylin and eosin. An experienced uropathologist evaluated the slides.RESULTS: The mean age of the patients was 69 years, and 80 (77%) were male. Pathological staging was T1-12 (12%), T2-20 (19%), T3-48 (47%) and T4-23 (22%). A mean (range) number of 31 (7-68) nodes per patient were examined, totalling 3 253 nodes. LN metastases were found in 41 patients (40%). SNs were detected in 83 of the 103 patients (80%). Sensitivity and specificity for detecting metastatic disease by SN biopsy (SNB) varied between LN stations, with average values of 67% and 90%, respectively. LN metastatic density (LNMD) had a significant prognostic impact; a value of ≥8% was significantly related to shorter survival. Lymphovascular invasion (LVI) occurred in 65% of patients (n = 67) and was significantly associated with shorter cancer-specific survival (P < 0.001).CONCLUSION: We conclude that SNB is not a reliable technique for peri-operative localization of LN metastases during cystectomy for BCa; however, LNMD has a significant prognostic value in BCa and may be useful in the clinical context and in BCa oncological and surgical research. LVI was also found to be a prognostic factor.
|
|
| 2. |
- Aljabery, Firas
(author)
-
Staging and tumor biological mechanisms of lymph node metastasis in invasive urinary bladder cancer
- 2017
-
Doctoral thesis (other academic/artistic)abstract
- Aim: To study the possibility of detecting lymph node metastasis in locally advanced urinary bladder cancer (UBC) treated with radical cystectomy (RC) by using preoperative positron emission tomography/computed tomography (PET/CT) and peroperative sentinel node biopsy (SNB) technique. We also investigate the clinical significance of macrophage traits expression by cancer cells, M2-macrophage infiltration (MI) in tumor stroma and the immunohistochemical expression of biomarkers in cancer cells in relation to clinicopathologic data.Patients and Methods: We studied prospectively 122 patients with UBC, pathological stage pT1–pT4 treated with RC and pelvic lymph node dissection (PLND) during 2005–2011 at the Department of Urology, Linköping University Hospital. In the first study, we compared the results of preoperative PET/CT and conventional CT with the findings of postoperative histopathological evaluation of lymph nodes (LNs). In the second study we investigated the value of SNB technique for detecting pathological LNs during RC in patients with UBC. W also examined the significance of the primary tumor location in the bladder in predicting the site of LN metastases, and the prognostic significance of lympho-vascular invasion (LVI) and lymph node metastasis density (LNMD) on survival. In the third study, we investigate the clinical significance of macrophage infiltration (MI) in tumor stroma and macrophage-traits expression by tumor cells. In the fourth study, we investigate the cell cycle suppression proteins p53, p21, pRb, p16, p14 ARF as well as tumors proliferative protein Ki67 and DNA repair protein ERCC1 expression in cancer cells. The results were compared with clinical and pathological characteristics and outcome.Results: Prior to RC, PET/CT was used to detect LN metastasis in 54 patients. PET/CT had 41% sensitivity, 86% specificity, 58% PPV, and 76% NPV, whereas the corresponding figures for conventional CT were 41%, 89%, 64%, and 77%. SNB was performed during RC in 103 patients. A median number of 29 (range 7–68) nodes per patient were examined. SNs were detected in 83 out of 103 patients (81%). The sensitivity and specificity for detecting metastatic disease by SNB varied among LN stations, with average values of 67% -90%. LNMD or ≥8% and LVI were significantly related to shorter survival. In 103 patients, MI was high in 33% of cases, while moderate and low infiltration occurred in 42% and 25% of tumors respectively. Patients with tumors containing high and moderate compared to low MI had low rate of LN metastases (P=0.06) and improved survival (P=0.06), although not at significant level. The expression of different tumor suppression proteins was altered in 47-91% of the patients. There were no significant association between cancer specific survival (CSS) and any of the studied biomarkers. In case of altered p14ARF, ERCC1 or p21, CSS was low in case of low p53 immunostaining but increased in case of p53 accumulation, although not at a significant level, indicating a possible protective effect of p53 accumulation in these cases.Conclusion: PET/ CT provided no improvement over conventional CT in detection and localization of regional LN metastases in bladder cancer. It is possible to detect the SN but the technique is not a reliable for perioperative localization of LN metastases; however, LVI and LNMD at a cut-off level of 8% had significant prognostic values. MI in the tumor microenvironment but not CD163 expression in tumor cells seems to be synergistic with the immune response against urinary bladder cancer. Our results further indicate that altered p53 might have protective effect on survival in case of altered p14ARF, p21, or ERCC1 indicating an interaction between these biomarkers.
|
|
| 3. |
|
|
| 4. |
- Bengtsson, Daniel, 1975-
(författare)
-
Cushing’s disease and aggressive pituitary tumours : Aspects on epidemiology, treatment, and long-term follow-up
- 2021
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on clinical and epidemiological aspects of aggressive pituitary tumours/carcinomas and Cushing’s disease. Pituitary carcinomas account for only 0.1-0.2% of the tumours originating from the anterior pituitary gland and are defined solely by the event of distant metastases, whereas aggressive pituitary tumours are defined by their clinical behaviour of rapid/progressive growth despite optimal treatment with surgery, radiotherapy and medical agents. The prognosis for individuals with aggressive tumours/carcinomas has been poor with few treatment options. However, case reports indicated better outcomes after treatment with the alkylating agent temozolomide. In study I and III, we investigated 24 patients (16 aggressive tumours and 8 carcinomas) given treatment with temozolomide. We found an initial response rate (tumour regression ≥30%) in 10/21 evaluable patients, with complete regression in two carcinomas. Favourable response was associated with low tumour expression of the DNA repair protein MGMT; in responders median 9% (range 5-20%) vs non-responders median 93% (50-100%). Our results also indicated a longer survival in patients with low MGMT. Out of 11 patients with MGMT >10%, nine died with an estimated median survival of 26 months (95% CI 14-38), whereas only 1/6 patients with lower MGMT died from tumour progression during a follow-up of median 83 months (range 12-161).One of the patients in study I and III had a corticotroph pituitary carcinoma and in addition, Lynch syndrome (LS), a hereditary cancer-predisposing syndrome caused by germline mutations in DNA mismatch repair (MMR) genes and primarily associated with colon and endometrial carcinomas. In study II, we investigated the characteristics of the pituitary carcinoma and found loss of MSH2 and MSH6 protein expression, consistent with the patient’s germline mutation in MSH2. This was the first published case of a pituitary tumour associated with LS. In addition, we identified all known Swedish patients with LS (n=910) and searched for diagnostic codes consistent with a pituitary tumour in the Swedish national patient register. We found in total three patients with clinically relevant pituitary tumours, the reported prevalence in the background population is around 1:1000.The last two studies in the thesis focused on Cushing’s disease (CD), i.e. an ACTH-secreting pituitary tumour resulting in excess levels of cortisol. CD is associated with multiple comorbidities and increased mortality. The reversibility of comorbidities and mortality risk after remission of cortisol levels have been under debate. Study IV examined psychiatric consequences of CD, measured by the use of psychotropic drugs. 179 patients with CD and a quadrupled matched control group were followed from diagnosis and at 5- and 10-year follow-up. We found that use of antidepressants remained at around 25% of patients with CD, regardless of remission status, at diagnosis and follow-up, whereas drugs for somatic comorbidities decreased. Use of antidepressants, sleeping pills and anxiolytics was higher in patients with CD compared to controls at diagnosis and 5-year follow-up. A cross-sectional analysis of 76 patients in sustained biochemical remission for median 9.3 years showed that 25% were taking antidepressants, a significantly higher use than controls, OR 2.0 (95% CI 1.1-3.8). In addition, patients with CD had a higher use of psychotropic drugs, already in the 5-year period before diagnosis.Study V investigated mortality and causes of death in 371 patients with CD, compared to a quadrupled matched control group. Follow-up was median 10.6 years (IQR 5.7-18.2) after time of diagnosis. Overall mortality was increased in patients with CD, HR 2.1 (95% CI 1.5-2.8) and remained elevated for patients in remission at last follow-up (n=303), HR 1.5 (1.02-2.2). For patients not in remission (n=31), HR was 5.6 (2.7-11.6). Cardiovascular diseases (32/66) and infections (12/66) were overrepresented causes of death in patients with CD. Main conclusions of the thesis:Temozolomide improves outcome in patients with aggressive pituitary tumours/carcinomas and a low MGMT expression in the tumour predicts a favourable outcome. As additional therapies evolve, MGMT may help to tailor the treatment.Germline mutations in MMR genes may contribute to the development and clinical course of pituitary tumours and may be a novel cause of hereditary pituitary tumours.Patients with Cushing’s disease have a high use of psychotropic drugs that remains elevated despite achievement of biochemical remission, suggesting persisting negative effects on mental health and highlighting the need for long-term monitoring of psychiatric symptoms. In addition, psychiatric symptoms may be early and important signs of CD.Efforts to achieve biochemical remission are crucial to reduce mortality in CD. However, patients in remission still have an increased mortality compared to controls. This underscores the need for life-long monitoring and treatment of associated comorbidities in patients with CD.
|
|
| 5. |
- Dutta, Ravi Kumar, 1983-
(författare)
-
Genetic and molecular alterations in aldosterone producing adenomas
- 2020
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Aldosterone producing tumors (APA, also known as Conn tumors) are adrenal tumors that overproduce aldosterone, a hormone that regulates the sodium levels in blood and contributes to blood pressure (BP) regulation. Excessive production of aldosterone causes hypertension and approximately 5-15% of hypertensive patients have hyperaldosteronism, known as primary aldosteronism (PA). Major causes of PA are bilateral adrenal hyperplasia (BAH) or aldosterone producing adenoma (APA) and about 30% of PA patients have APAs. In most cases, the disease is unilateral, in rare case bilateral. Patients with APA are often detected when they have elevated blood pressure (BP>160/100mmHg) or when BP cannot be controlled with drugs. Surgery dramatically normalizes or lowers BP in patients with APA.In this thesis, we first explored the mutation frequency in susceptibility genes in sporadic APAs. About 60% of APAs displayed complementary mutations in the KCNJ5, ATP1A1, ATP2B3, CTNNB1, CACNAID and CLCN2 genes (Paper I, II & III). Copy number variation analysis of 35 APAs identified amplification of chromosome 10q24.31 in two tumors, where CALHM1-3- genes encoding for potential calcium ion channels are located. Only CALHM2 is expressed in adrenals and sequencing of CALHM2 revealed three different heterozygous sequence variants; c.341_42delCT (CALHM2P114Rfs*12), c.286G>A (CALHM2A96T) and c.580G>A (CALHM2V194M) in 5 APAs. CALHM2 is expressed in the mitochondrial membranes and Ca2+ imaging revealed that CALHM2 has selection of another ion rather than Ca2+. The genetic variant CALHM2V194M converts CALHM2 into a non-selective channel and results in higher Ca2+ conductance in mitochondria. We further found that loss of CALHM2 function upregulates REELIN/LRP8 signaling activating β-catenin dependent transcription of target genes (Paper II). In Paper IV, we investigated Scandinavian APA cases (n=35) and Swedish controls (n=60) for GWAS and discovered a susceptibility locus on chromosome Xq13.3 in a 4 Mb region to be significantly associated with APAs. Significance level was still same after genotyping the sentinel SNP rs2224095 in a replication cohort of APAs (n=52) and controls (n=740). Sequencing of an adjacent gene of the sentinel SNP, MAGEE1, identified a rare variant in one APA, which is complementary to other mutations in our primary cohort. In Summary, our studies have increased the knowledge of molecular genetic events in APAs. The results may contribute to find future non-surgical treatments for APAs.
|
|
| 6. |
- Eneholm, Johan, et al.
(författare)
-
A retrospective study comparing minimally invasive versus open surgical resection of small intestinal neuroendocrine neoplasms at a tertiary referral center
- 2024
-
Ingår i: European Journal of Surgical Oncology. - : Elsevier. - 0748-7983 .- 1532-2157. ; 50:2
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: Neuroendocrine neoplasms (SI-NEN) are the commonest malignancies of the small intestine. Traditionally, surgical treatment for SI-NEN has been open surgery.Purpose: The purpose of this study was to compare minimally invasive surgery (MIS) with the traditional open surgery approach for treating SI-NEN in a Swedish population.Methods: Patients with histopathological confirmed SI-NEN who underwent open surgery or MIS resection within 2009-2021 were extracted from the hospital's medical records.Results: 65 patients were included in this study, with 35 (54 %) undergoing MIS and 30 (46 %) undergoing open surgery. We found no statistically significant difference (p = 0.173) in the frequency of R0 resections (MIS group n = 34 (97 %), open surgery group n = 26 (87 %)). Nor was there a significant difference (p = 0.101) when comparing the median number of resected lymph nodes (MIS group n = 13.5, open surgery group n = 10). A post-operative paralytic ileus was more often reported (p = 0.052) in the MIS group (n = 9, 26 %) compared to the open surgery group (n = 2, 7 %). In light of this, the days of hospital stay did not differ significantly (MIS group median = 6, IQR (5-8), open surgery group median = 6, IQR (5-9)). The Kaplan-Meier analysis did not reveal differences concerning cancer-related deaths (p = 0.109).Conclusion: The results from this study support that a MIS approach for the treatment of SI-NEN may not be inferior to open surgery. The higher number of resected lymph nodes and R0 resections may even speak in favor for a MIS approach. More studies with a longer time of observation are needed to further support this conclusion.
|
|
| 7. |
- Haj-Hosseini, Neda, 1980-, et al.
(författare)
-
Optiska metoder för identifiering av bisköldkörtel och sköldkörtel
- 2017
-
Konferensbidrag (refereegranskat)abstract
- Identifiering av bisköldkörtlar är viktigt vid sköldkörtel- och bisköldkörtelkirurgi och kan vara svårt då de liknar omgivande vävnad såsom fett och lymfkörtlar. Peroperativ detektering av dessa vävnader kan förbättra möjligheten att bota patienter med hyperparathyroidism och minska risken för bisköldkörtelskador vid thyroideakirurgi. Optiska metoder är potentiella tekniker för att möjliggöra detta. Optiska tekniker utvärderades på vävnadsprover från patienter vid bisköldkörtel- och sköldkörteloperation. Teknikerna bestod av nära infraröd fluorescens (NIR) spektroskopi och optisk koherenstomografi (OCT) som ger en bild av vävnadens mikrostruktur liknande till ultraljud med högre upplösning (10 μm).
|
|
| 8. |
- Heenkenda, Menikae Kanchena, 1982-
(författare)
-
Understanding and Managing Thrombotic Risks in Medical Conditions : One Size Does Not Fit All
- 2024
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Hemostasis is a critical physiological process that stops bleeding at the site of an injury while ensuring normal blood flow elsewhere, thereby preventing excessive clot formation that could lead to dangerous conditions like thrombosis. This delicate balance is influenced by genetics, medical conditions such as cancer, and various medications. When a blood vessel is damaged, platelets adhere to the exposed area, become activated, and aggregate to form an initial plug. Coagulation factors, particularly thrombin, create a strong fibrin network to stabilize the clot. Disruptions in this process can result in significant bleeding or dangerous clot formation.This thesis aims to explore and understand the factors affecting coagulation and the risks of thrombotic events in different medical contexts. This includes studying genetic variability in the protease-activated receptor 4 (PAR4) gene (specifically the Ala120Thr variant) among sub-Saharan African populations, identifying genetic and non-genetic risk factors for venous thromboembolism (VTE) in patients with the brain cancer glioblastoma multiforme (GBM), and investigating the impact of intravenous morphine on platelet activity in patients with ST-elevation myocardial infarction (STEMI) treated with ticagrelor, a P2Y12 inhibitor. The A allele of the rs773902 single-nucleotide polymorphism (SNP) in the PAR4 gene (F2RL3) substitutes threonine for alanine at the 120th protein position (Thr120). This allele is more prevalent in African populations compared to Caucasian populations, although previous studies did not specify the geographic ancestry of participants. Thr120 is associated with higher PAR4-induced human platelet aggregation and Ca2+ flux. Our study found that the frequency of the A allele in the Somali population is significantly lower than previously reported for African Americans. The A allele frequency in Somalis is 38%, compared to 63% for African Americans. The A allele frequency in Somalis is closer to that of the Maasai population in Kenya (41%), but vastly different from the Esan population in Nigeria (68%). Certain cancers, such as GBM, are associated with a higher risk of VTE, including deep vein thrombosis (DVT) and pulmonary embolism (PE). Our research identified blood group B as a significant risk factor for patients with GBM (OR=6.91; 95% CI=2.2–24.1; P =0.001). Also, GBM tumors in the frontal lobe are associated with an increased risk of VTE (OR=3.14; 95% CI=1.1–10.7; P =0.05). Our study on morphine, commonly used for pain management in STEMI patients, found that morphine is associated with increased platelet aggregation one hour after percutaneous coronary intervention (PCI), impacting the efficacy of ticagrelor. Morphine delays platelet inhibition by affecting the pharmacodynamics of antiplatelet therapy, likely by delaying gastric emptying. However, this effect is short-lived, as platelet reactivity returns to similar levels in both groups 12 hours post-PCI. Despite this immediate impact on platelet function, our research found no significant differences in biomarkers of platelet activity, coagulation, or inflammation between the morphine and non-morphine groups. Additionally, all patients in our study were administered unfractionated heparin injections or bivalirudin infusion during primary PCI, which may help control the risk of blood clot formation. These studies collectively emphasize the need for individualized strategies to manage thrombotic risks and coagulation. The significant genetic variability among sub-Saharan African populations highlights the need for precise genetic research to understand how genetics influence coagulation and develop personalized medical strategies. The increased risk of cancer-associated thrombosis, particularly in patients with GBM, calls for individualized anticoagulant therapies based on unique risk profiles, such as blood group typing and tumor location. Incorporating these insights into clinical practice can help healthcare providers better identify high-risk patients and tailor thromboprophylaxis strategies accordingly. Similarly, the impact of morphine on patients with STEMI treated with ticagrelor requires careful consideration. In conclusion, these findings underscore the importance of a personalized approach in managing coagulation and thrombotic risks. The studies show that genetic variability, specific medical conditions, and medication effects are crucial in thrombotic risk. Therefore, customized strategies based on individual patient profiles and contexts are essential for effectively managing and preventing thrombotic events.
|
|
| 9. |
- Lundgren, Linda, 1973-
(författare)
-
Incidental Gallbladder Cancer : Incidence, predictors, management and outcome in a Swedish population
- 2019
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Cholecystectomy is a common surgical procedure and incidental gallbladder cancer is a rare and unexpected finding at a cholecystectomy performed upon benign indications. Whether to perform routine or selective histopathology of the gallbladder specimen is still a subject for discussion. The prognosis of gallbladder cancer is largely affected by tumour stage and treatment.Aims: The overall aim was to study whether routine histological examination of the gallbladder specimen is of clinical and health economic value; determine if there are any predictive factors of incidental gallbladder cancer at benign cholecystectomy and compare the management and outcome of incidental gallbladder cancer patients in Sweden.Methods: All studies were based on registry data from GallRiks (The Swedish Registry for Gallstone Surgery and Endoscopic Retrograde Cholangiopancreatography) between 2007 and 2016, with some modifications between studies. Complemental cross-linkage was made to national registries, and medical records were reviewed. Papers I, II and III were population-based observational studies with prospectively and retrospectively collected data. Paper IV was a health economic evaluation based on the results from papers I and III.Results and conclusions: Hospitals submitting >75 per cent of gallbladder specimens diagnosed a higher proportion of incidental gallbladder cancer than did hospitals submitting ≤25 per cent of samples (paper I). Incidental gallbladder cancer was more prevalent in older patients, women and patients with acute or previous cholecystitis, as well as ongoing jaundice. The risk model based on predictive preoperative factors was further improved by adding a macroscopic assessment of the gallbladder (paper II). Predictive factors for gallbladder cancer appeared to have an impact on which specimens were submitted in hospitals with a selective approach of histopathology (paper I). For pT2 and pT3 patients, re-resection improved diseasespecific survival, although these groups differed in terms of age and comorbidity (paper III). Residual disease was an independent factor for impaired survival. A change to routine histopathology of gallbladder specimens in Sweden would lead to increased costs with little improved health outcomes. Instead, a more standardized approach to selective histology would be needed (paper IV).
|
|
| 10. |
- Lundgren, Linda, et al.
(författare)
-
Management of incidental gallbladder cancer in a national cohort
- 2019
-
Ingår i: British Journal of Surgery. - : Oxford University Press (OUP). - 0007-1323 .- 1365-2168. ; 106:9, s. 1216-1227
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Incidental gallbladder cancer is a rare event, and its prognosis is largely affected by the tumour stage and treatment. The aim of this study was to analyse the management, treatment and survival of patients with incidental gallbladder cancer in a national cohort over a decade. Methods: Patients were identified through the Swedish Registry of Gallstone Surgery (GallRiks). Data were cross-linked to the national registry for liver surgery (SweLiv) and the Cancer Registry. Medical records were collected if registry data were missing. Survival was measured as disease-specific survival. The study was divided into two intervals (2007–2011 and 2012–2016) to evaluate changes over time. Results: In total, 249 patients were identified with incidental gallbladder cancer, of whom 92 (36·9 per cent) underwent re-resection with curative intent. For patients with pT2 and pT3 disease, median disease-specific survival improved after re-resection (12·4 versus 44·1 months for pT2, and 9·7 versus 23·0 months for pT3). Residual disease was present in 53 per cent of patients with pT2 tumours who underwent re-resection; these patients had a median disease-specific survival of 32·2 months, whereas the median was not reached in patients without residual disease. Median survival increased by 11 months for all patients between the early and late periods (P = 0·030). Conclusion: Re-resection of pT2 and pT3 incidental gallbladder cancer was associated with improved survival, but survival was impaired when residual disease was present. A higher re-resection rate and more R0 resections in the later time period may have been associated with improved survival.
|
|
| 11. |
- Rezaei, Shiva, et al.
(författare)
-
GBS-MeDIP : A protocol for parallel identification of genetic and epigenetic variation in the same reduced fraction of genomes across individuals
- 2022
-
Ingår i: STAR protocols. - : Cell Press. - 2666-1667. ; 3:1
-
Tidskriftsartikel (refereegranskat)abstract
- The GBS-MeDIP protocol combines two previously described techniques, Geno-type-by-Sequencing (GBS) and Methylated-DNA- Immunoprecipitation (MeDIP). Our method allows for parallel and cost-efficient interrogation of genetic and methylomic variants in the DNA of many reduced genomes, taking advantage of the barcoding of DNA samples performed in the GBS and the subsequent creation of DNA pools, then used as an input for the MeDIP. The GBS-MeDIP is particularly suitable to identify genetic and methylomic biomarkers when resources for whole genome interrogation are lacking.
|
|
| 12. |
- Rezaei, Shiva, et al.
(författare)
-
GBS-MeDIP: A protocol for parallel identification of genetic and epigenetic variation in the same reduced fraction of genomes across individuals
- 2022
-
Ingår i: STAR Protocols. - : Cell Press. - 2666-1667. ; 3:1
-
Tidskriftsartikel (refereegranskat)abstract
- Summary:The GBS-MeDIP protocol combines two previously described techniques, Genotype-by-Sequencing (GBS) and Methylated-DNA-Immunoprecipitation (MeDIP). Our method allows for parallel and cost-efficient interrogation of genetic and methylomic variants in the DNA of many reduced genomes, taking advantage of the barcoding of DNA samples performed in the GBS and the subsequent creation of DNA pools, then used as an input for the MeDIP. The GBS-MeDIP is particularly suitable to identify genetic and methylomic biomarkers when resources for whole genome interrogation are lacking.
|
|
| 13. |
- Tabebi, Mouna, et al.
(författare)
-
Genetic Alterations in Mitochondrial DNA Are Complementary to Nuclear DNA Mutations in Pheochromocytomas
- 2022
-
Ingår i: Cancers. - : MDPI. - 2072-6694. ; 14:2
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Somatic mutations, copy-number variations, and genome instability of mitochondrial DNA (mtDNA) have been reported in different types of cancers and are suggested to play important roles in cancer development and metastasis. However, there is scarce information about pheochromocytomas and paragangliomas (PCCs/PGLs) formation.Material: To determine the potential roles of mtDNA alterations in sporadic PCCs/PGLs, we analyzed a panel of 26 nuclear susceptibility genes and the entire mtDNA sequence of seventy-seven human tumors, using next-generation sequencing, and compared the results with normal adrenal medulla tissues. We also performed an analysis of copy-number alterations, large mtDNA deletion, and gene and protein expression.Results: Our results revealed that 53.2% of the tumors harbor a mutation in at least one of the targeted susceptibility genes, and 16.9% harbor complementary mitochondrial mutations. More than 50% of the mitochondrial mutations were novel and predicted pathogenic, affecting mitochondrial oxidative phosphorylation. Large deletions were found in 26% of tumors, and depletion of mtDNA occurred in more than 87% of PCCs/PGLs. The reduction of the mitochondrial number was accompanied by a reduced expression of the regulators that promote mitochondrial biogenesis (PCG1α, NRF1, and TFAM). Further, P62 and LC3a gene expression suggested increased mitophagy, which is linked to mitochondrial dysfunction.Conclusion: The pathogenic role of these finding remains to be shown, but we suggest a complementarity and a potential contributing role in PCCs/PGLs tumorigenesis.
|
|
| 14. |
- Tabebi, Mouna, et al.
(författare)
-
Loss of SDHB Induces a Metabolic Switch in the hPheo1 Cell Line toward Enhanced OXPHOS
- 2022
-
Ingår i: International Journal of Molecular Sciences. - Basel, Switzerland : MDPI. - 1661-6596 .- 1422-0067. ; 23:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Enzymes of tricarboxylic acid (TCA) have recently been recognized as tumor suppressors. Mutations in the SDHB subunit of succinate dehydrogenase (SDH) cause pheochromocytomas and paragangliomas (PCCs/PGLs) and predispose patients to malignant disease with poor prognosis.Methods: Using the human pheochromocytoma cell line (hPheo1), we knocked down SDHB gene expression using CRISPR-cas9 technology.Results: Microarray gene expression analysis showed that >500 differentially expressed gene targets, about 54%, were upregulated in response to SDHB knock down. Notably, genes involved in glycolysis, hypoxia, cell proliferation, and cell differentiation were up regulated, whereas genes involved in oxidative phosphorylation (OXPHOS) were downregulated. In vitro studies show that hPheo1 proliferation is not affected negatively and the cells that survive by shifting their metabolism to the use of glutamine as an alternative energy source and promote OXPHOS activity. Knock down of SDHB expression results in a significant increase in GLUD1 expression in hPheo1 cells cultured as monolayer or as 3D culture. Analysis of TCGA data confirms the enhancement of GLUD1 in SDHB mutated/low expressed PCCs/PGLs.Conclusions: Our data suggest that the downregulation of SDHB in PCCs/PGLs results in increased GLUD1 expression and may represent a potential biomarker and therapeutic target in SDHB mutated tumors and SDHB loss of activity-dependent diseases.
|
|
| 15. |
- Tamás, Éva, 1968-, et al.
(författare)
-
Gender and Assigned Role Influences Medical Students´ Learning Experience in Interprofessional Team Training Simulations
- 2017
-
Ingår i: MedEdPublish. - Dundee, UK : Association for Medical Education in Europe. - 2312-7996. ; 6:1
-
Tidskriftsartikel (refereegranskat)abstract
- The advantages of providing standardized education avoiding exposure of real patients to interventions by novices are appealing both from patient safety and teaching aspects, thus medical simulation has become an integrated part of the healthcare curriculum.We explored the impact of gender and an acting vs. an observing role in simulation on students’ perceptions of learning outcomes, and of simulation as a learning activity.A prospective survey for graduating medical students participating in a full day simulated team training session was conducted over three terms. The questionnaire addressed issues related to the session, teamwork and simulation training in general. Participation was voluntary and the study was approved by the regional ethics committee.The overall response rate was 90.8 %. Authenticity and relevance were considered to be high, though male students scored significantly higher both for authenticity and for relevance. Communication and teamwork were considered to be different, depending on gender and assigned role. Female students and students in an acting role were more ready to discuss knowledge gaps, experienced “good” communication significantly more often, and defined their work as teamwork more frequently. The scenarios were found to be more stimulating and motivating by female students and acting individuals. Self-confidence and self-awareness were declared to be more enhanced for male students and for those who were acting during the simulation sessions. Observers and female students scored significantly lower as regards satisfaction with both the extent of the reflection and the individual feedback.The perceptions of authenticity and relevance of simulation sessions and students’ readiness to discuss knowledge gaps differed between genders. Furthermore, perceived changes in self-confidence and self-awareness seemed to be different. The observing role implies a different kind of learning process, which is not necessarily inferior to learning by acting.
|
|
| 16. |
|
|
| 17. |
- Toledo, Rodrigo A., et al.
(författare)
-
Consensus Statement on next-generation-sequencing-based diagnostic testing of hereditary phaeochromocytomas and paragangliomas
- 2017
-
Ingår i: Nature Reviews Endocrinology. - : NATURE PUBLISHING GROUP. - 1759-5029 .- 1759-5037. ; 13:4, s. 233-247
-
Tidskriftsartikel (refereegranskat)abstract
- Phaeochromocytomas and paragangliomas (PPGLs) are neural-crest-derived tumours of the sympathetic or parasympathetic nervous system that are often inherited and are genetically heterogeneous. Genetic testing is recommended for patients with these tumours and for family members of patients with hereditary forms of PPGLs. Due to the large number of susceptibility genes implicated in the diagnosis of inherited PPGLs, next-generation sequencing (NGS) technology is ideally suited for carrying out genetic screening of these individuals. This Consensus Statement, formulated by a study group comprised of experts in the field, proposes specific recommendations for the use of diagnostic NGS in hereditary PPGLs. In brief, the study group recommends target gene panels for screening of germ line DNA, technical adaptations to address different modes of disease transmission, orthogonal validation of NGS findings, standardized classification of variant pathogenicity and uniform reporting of the findings. The use of supplementary assays, to aid in the interpretation of the results, and sequencing of tumour DNA, for identification of somatic mutations, is encouraged. In addition, the study group launches an initiative to develop a gene-centric curated database of PPGL variants, with annual re-evaluation of variants of unknown significance by an expert group for purposes of reclassification and clinical guidance.
|
|
| 18. |
- Welander, Jenny, et al.
(författare)
-
Activating FGFR1 mutations in sporadic pheochromocytoma
- 2018
-
Ingår i: World Journal of Surgery. - : Springer. - 0364-2313 .- 1432-2323. ; 42:2, s. 482-489
-
Tidskriftsartikel (refereegranskat)abstract
- Pheochromocytomas are neuroendocrine tumors of the adrenal glands that cause hypertension. More than a third of the cases are associated with hereditary mutations in a growing list of susceptibility genes, some of which are also somatically altered in sporadic pheochromocytomas. However, for the majority of sporadic pheochromocytomas, a genetic explanation is still lacking. Here we investigated the genomic landscape of sporadic pheochromocytomas with whole-exome sequencing of 16 paired tumor and normal DNA samples, and discovered on average 33 non-silent somatic mutations per tumor. One of the recurrently mutated genes was FGFR1, encoding the fibroblast growth factor receptor 1, which was recently revealed as an oncogene in pilocytic astrocytoma and childhood glioblastoma. Including a subsequent analysis of a larger cohort, activating FGFR1 mutations were detected in three of 80 sporadic pheochromocytomas (3.8%). Gene expression microarray profiling showed that these tumors clustered with NF1- RET- and HRAS-mutated pheochromocytomas, indicating activation of the MAPK and PI3K-AKT signal transduction pathways. The results advance our biological understanding of pheochromocytoma and suggest that somatic FGFR1 activation is an important event in a subset of these tumors.
|
|
