| 1. |
- Biermann, Jana, et al.
(författare)
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Radiation-induced genomic instability in breast carcinomas of the Swedish haemangioma cohort.
- 2019
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Ingår i: Genes, chromosomes & cancer. - : Wiley. - 1098-2264 .- 1045-2257. ; 58:9, s. 627-35
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Tidskriftsartikel (refereegranskat)abstract
- Radiation-induced genomic instability (GI) is hypothesized to persist after exposure and ultimately promote carcinogenesis. Based on the absorbed dose to the breast, an increased risk of developing breast cancer was shown in the Swedish haemangioma cohort that was treated with radium-226 for skin haemangioma as infants. Here, we screened 31 primary breast carcinomas for genetic alterations using the OncoScan CNV Plus Assay to assess GI and chromothripsis-like patterns associated with the absorbed dose to the breast. Higher absorbed doses were associated with increased numbers of copy number alterations (CNAs) in the tumour genome and thus a more unstable genome. Hence, the observed dose-dependent GI in the tumour genome is a measurable manifestation of the long-term effects of irradiation. We developed a highly predictive Cox regression model for overall survival based on the interaction between absorbed dose and GI. The Swedish haemangioma cohort is a valuable cohort to investigate the biological relationship between absorbed dose and GI in irradiated humans. This work gives a biological basis for improved risk assessment to minimize carcinogenesis as a secondary disease after radiation therapy. This article is protected by copyright. All rights reserved.
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| 2. |
- Biermann, Jana, et al.
(författare)
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Tumour clonality in paired invasive breast carcinomas
- 2019
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Ingår i: Cancer Research. - 0008-5472.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Background: Multiple invasive breast tumours may represent either independent primary tumours or clonal recurrences of the first tumour, where the same progenitor cell gives rise to all of the detected tumours. Consequently, the driver events for the progenitor cell need to have been identical in early tumour development. Molecular classification of tumour clonality is not currently evaluated in multiple invasive breast carcinomas, despite evidence suggesting common clonal origins. Furthermore, there is no consensus about which type of biological data (e.g. copy number, mutation, histology) and especially which statistical method is most suitable to distinguish clonal recurrences from independent primary tumours. Methods: Thirty-seven invasive breast tumour pairs were stratified by laterality (bilateral vs. ipsilateral) and the time interval between the diagnoses of the first and second tumours (synchronous vs. metachronous). Both tumours from the same patient were analysed by integrating clinical characteristics (n = 37), DNA copy number (n = 37), DNA methylation (n = 8), gene expression microarray (n = 7), RNA sequencing (n = 3), and SNP genotyping data (n = 3). Different statistical methods, e.g. the diagnostic similarity index (SI), distance measure, shared segment analysis etc., were used to classify the tumours from the same patient as clonally related recurrences or independent primary tumours. Results: The SI applied on DNA copy numbers derived from aCGH (array comparative genomic hybridization) data was determined as the strongest indicator of clonal relatedness as it showed the highest concordance with all other methods. The distance measure was the most conservative method and the shared segment analysis most liberal. Concordant evidence for tumour clonality was found in 46% (17/37) of the patients. Notably, no significant association was found between the clinical characteristics and molecular tumour features. Conclusions: A more accurate classification of clonal relatedness between multiple breast tumours may help to mitigate treatment failure and relapse by integrating tumour-associated molecular features, clinical parameters, and statistical methods. In cases of extremely similar or different tumour pairs, the results showed consistency regardless of the method used. The SI can be easily integrated into clinical routine using FFPE samples to obtain copy number data. However, clinical guidelines with exact thresholds need to be defined to standardize clonality testing in a routine diagnostic setting.
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| 3. |
- Biermann, Jana
(författare)
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Tumour evolution and novel biomarkers in breast cancer
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Several gene signatures have been proposed in the past two decades to improve outcome prediction for breast cancer patients and to guide treatment decisions. Current treatment guidelines, however, primarily focus on established clinicopathological features. In Paper I, we identified a novel 18-marker gene expression signature predicting breast cancer-specific survival. The 18-marker signature was validated in three independent cohorts and showed increased predictive power over the clinically validated Oncotype Dx signature. Despite increasing survival rates, about 6-23% of patients suffer from recurrences within five years of initial diagnosis indicating treatment failure. It is highly important to differentiate between clonally related recurrences and independent primary tumours due to potentially differing prognoses and treatment regimes. Currently, there is no consensus on how to define clonal relatedness between multiple tumours in the same patient. In Paper II, we identified the Similarity Index (SI) as the most reliable tool to classify tumour clonality. The mammary gland is known to be highly sensitive to radiation, especially at a young age. In the years from 1920-1965, a total of 17,200 female Swedish infants were treated with ionizing radiation for skin haemangioma, resulting in an increased risk of developing breast cancer. In Paper III, we analysed breast tumours for genomic instability, which can be induced by ionizing radiation. Patients with higher absorbed doses to the breast exhibited increased genomic instability compared to patients exposed to lower absorbed doses. These results strongly suggest radiation-induced genomic instability as a biological link between ionizing radiation exposure at a young age and the increased breast cancer risk in subsequent decades. In conclusion, this work highlights the importance of complementing established clinicopathological features with molecular biology and statistical models to improve breast cancer risk assessment and personalize treatment strategies.
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| 4. |
- Engqvist, Hanna, 1985, et al.
(författare)
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Immunohistochemical validation of COL3A1, GPR158 and PITHD1 as prognostic biomarkers in early-stage ovarian carcinomasn
- 2019
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Ingår i: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 19:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Ovarian cancer is the main cause of gynecological cancer-associated death. However, 5- Methods: Here, we evaluated the prognostic role of 29 genes for early-stage (I and II) ovarian Results: We provide evidence of aberrant protein expression patterns for Collagen type III alpha 1 Conclusions: The novel biomarkers identified here may improve prognostication at the time of
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| 5. |
- Jana, Somnath, et al.
(författare)
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Charge disproportionate antiferromagnetism at the verge of the insulator-metal transition in doped LaFeO3
- 2019
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Ingår i: Physical Review B. - : American Physical Society. - 2469-9950 .- 2469-9969. ; 99:7
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Tidskriftsartikel (refereegranskat)abstract
- We explore the effects of electron doping in lanthanum ferrite, LaFeO3 by doping Mo at the Fe sites. Based on magnetic, transport, scanning tunneling spectroscopy, and x-ray photoelectron spectroscopy measurements, we find that the large gap, charge-transfer, antiferromagnetic (AFM) insulator LaFeO3 becomes a small gap AFM band insulator at low Mo doping. With increasing doping concentration, Mo states, which appear around the Fermi level, is broadened and become gapless at a critical doping of 20%. Using a combination of calculations based on density functional theory plus Hubbard U (DFT+U) and x-ray absorption spectroscopy measurements, we find that the system shows charge disproportionation (CD) in Fe ions at 25% Mo doping, where two distinct Fe sites, having Fe2+ and Fe3+ nominal charge states appear. A local breathing-type lattice distortion induces the charge disproportionation at the Fe site without destroying the antiferromagnetic order. Our combined experimental and theoretical investigations establish that the Fe states form a CD antiferromagnet at 25% Mo doping, which remains insulating, while the appearance of Mo states around the Fermi level is showing an indication towards the insulator-metal transition.
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