Histological type and marker expression of the primary tumour compared with its local recurrence after breast-conserving therapy for ductal carcinoma in situ

We have investigated primary ductal carcinomas in situ (DCIS) of the breast and their local recurrences after breast-conserving therapy (BCT) for histological characteristics and marker expression. Patients who were randomized in the EORTC trial 10853 (wide local excision versus excision plus radiotherapy) and who developed a local recurrence were identified. Histology was reviewed for 116 cases; oestrogen and progesterone receptor status, and HER2/ neu and p53 overexpression were assessed for 71 cases. Comparing the primary DCIS and the invasive or non-invasive recurrence, concordant histology was found in 62%, and identical marker expression in 63%. Although 11% of the recurrences developed at a distance from the primary DCIS, nearly all these showed the same histological and immunohistochemical profile. 5 patients developed well-differentiated DCIS or grade I invasive carcinoma after poorly differentiated DCIS. Although these recurrences occurred in the same quadrant as the primary DCIS, they may be considered as second primary tumours. Only 4 patients developed poorly differentiated DCIS or grade III invasive carcinoma after well differentiated DCIS. We conclude that in most cases the primary DCIS and its local recurrence are related histologically or by marker expression, suggesting that local recurrence usually reflects outgrowth of residual DCIS; progression of well differentiated DCIS towards poorly differentiated DCIS or grade III invasive carcinoma is a non-frequent event. © 2001 Cancer Research Campaign http://www.bjcancer.co

Use of Preclinical Models to Improve Treatment of Retinoblastoma

Dyer and colleagues examine the most promising preclinical models that recapitulate the molecular, genetic, and cellular features of retinoblastoma

Adenomatous polyposis coli-mediated control of β-catenin is essential for both chondrogenic and osteogenic differentiation of skeletal precursors

Background: During skeletogenesis, protein levels of β-catenin in the canonical Wnt signaling pathway determine lineage commitment of skeletal precursor cells to osteoblasts and chondrocytes. Adenomatous polyposis coli (Apc) is a key controller of β-catenin turnover by down-regulating intracellular levels of β-catenin. Results: To investigate whether Apc is involved in lineage commitment of skeletal precursor cells, we generated conditional knockout mice lacking functional Apc in Col2a1-expressing cells. In contrast to other models in which an oncogenic variant of β-catenin was used, our approach resulted in the accumulation of wild type β-catenin protein due to functional loss of Apc. Conditional homozygous Apc mutant mice died perinatally showing greatly impaired skeletogenesis. All endochondral bones were misshaped and lacked structural integrity. Lack of functional Apc resulted in a pleiotropic skeletal cell phenotype. The majority of the precursor cells lacking Apc failed to differentiate into chondrocytes or osteoblasts. However, skeletal precursor cells in the proximal ribs were able to escape the noxious effect of functional loss of Apc resulting in formation of highly active osteoblasts. Inactivation of Apc in chondrocytes was associated with dedifferentiation of these cells. Conclusion: Our data indicate that a tight Apc-mediated control of β-catenin levels is essential for differentiation of skeletal precursors as well as for the maintenance of a chondrocytic phenotype in a spatio-temporal regulated manner

The diagnostic pathway of Parkinson's disease: A cross-sectional survey study of factors influencing patient dissatisfaction

Background: The diagnostic pathway of Parkinson’s disease (PD) is often complicated. Experiences during this pathway can affect patients’ satisfaction and their confidence and trust in healthcare providers. Although healthcare providers cannot influence the impact of the diagnosis, they can influence how patients experience the pathway. This study, therefore, aims to provide insight into PD patients’ dissatisfaction with the diagnostic pathway and to describe the factors that influence it. Methods: We carried out a cross-sectional survey study among 902 patient members of the Dutch Parkinson’s Disease Association, who were each asked to write an essay about their diagnostic pathway. A coding format was developed to examine the content of these essays. Inter-observer agreement on coding patient dissatisfaction was calculated using Cohen’s kappa. The χ2 test and a multivariable logistic regression analysis were performed to assess the relation between dissatisfaction and sex, level of education, duration of the pathway, communication with the general practitioner (GP) and the neurologist, the number of healthcare providers involved, whether or not a second opinion had taken place (including the person who initiated it) and diagnostic delay (taking into consideration who caused the delay according to the patient). A subgroup analysis was performed to gain insight into sex-related differences. Results: Of all patients, 16.4% explicitly described they were dissatisfied with the diagnostic pathway, whereas 4.8% were very satisfied. The inter-observer agreement on coding dissatisfaction was κ = 0.82. The chance of dissatisfaction increased with a lower level of education, the involvement of more than one additional healthcare provider, a second opinion initiated by the patient and delay caused by a healthcare provider. When only the GP and the neurologist were involved, women were more likely to be dissatisfied than men. Conclusions: PD patients’ dissatisfaction with the diagnostic pathway is related to a lower level of education, a second opinion initiated by the patient and experienced diagnostic delay. GPs can positively influence patients’ experiences if they are aware of these risk factors for dissatisfaction and pay extra attention to communication and shared decision making. This will contribute to a trusting therapeutic relationship that is indispensable with progression of the diseaseThis study was supported by funds of the Dutch Parkinson’s Disease Association (Funding number 2012-V15) and the Health Insurers Innovation Foundation (Funding number 2687)

Avoiding false-positive signals with nuclease-vulnerable molecular beacons in single living cells

There have been a growing number of studies where molecular beacons (MBs) are used to image RNA expression in living cells; however, the ability to make accurate measurements can be hampered by the generation of false-positive signals resulting from non-specific interactions and/or nuclease degradation. In the present study, we found that such non-specific signals only arise in the nucleus of living cells. When MBs are retained in the cytoplasmic compartment, by linking them to quantum dots (QDs), false-positive signals are reduced to marginal levels. Consequently, MB–QD conjugates were used to measure the expression of the endogenous proto-oncogene c-myc in MCF-7 breast cancer cells by quantifying the total fluorescent signal emanating from individual cells. Upon the addition of tamoxifen, measurements of MB fluorescence indicated a 71% reduction in c-myc expression, which correlated well with RT-PCR measurements. Variations in MB fluorescence resulting from instrumental fluctuations were accounted for by imaging fluorescent calibration standards on a daily basis. Further, it was established that measurements of the total fluorescent signal were not sensitive to the focal plane. Overall, these results provide evidence that accurate measurements of RNA levels can be made when MBs are retained in the cytoplasm

Time Trends in the Incidence and Treatment of Extra-Abdominal and Abdominal Aggressive Fibromatosis: A Population-Based Study

BACKGROUND: Aggressive fibromatosis (AF) is a locally infiltrating soft-tissue tumor. In a population-based study in the Netherlands, we evaluated time trends for the incidence and treatment of AF. METHODS: In PALGA: Dutch Pathology Registry, all patients diagnosed between 1993 and 2013 as having extra-abdominal or abdominal wall aggressive fibromatosis were identified and available pathology data of the patients were evaluated. Epidemiological and treatment-related factors were analyzed with χ(2)and regression analysis. RESULTS: During the study period, 1134 patients were identified. The incidence increased from 2.10 to 5.36 per million people per year. Median age at the time of diagnosis increased annually by B 0.285 (P = 0.001). Female gender prevailed and increased over time [annual odds ratio (OR) 1.022; P = 0.058]. All anatomic localizations, but in particular truncal tumors, became more frequent. During the study period diagnostic histological biopsies were performed more often (annual OR 1.096; P < 0.001). The proportion of patients who underwent surgical treatment decreased (annual OR 0.928; P < 0.001). When resection was preceded by biopsy, 49.8 % of the patients had R0-resection versus 30.7 % in patients without biopsy (P < 0.001). CONCLUSIONS: In this population-based study, an increasing incidence of extra-abdominal and abdominal-wall aggressive fibromatosis was observed. The workup of patients improved and a trend towards a nonsurgical treatment policy was observed

Increased copy number at 3p14 in breast cancer

INTRODUCTION: The present study was conducted to investigate if chromosome band 3p14 is of any pathogenic significance in the malignant process of breast cancer. Genetic studies have implicated a tumour suppressor gene on chromosome arm 3p and we have proposed LRIG1 at 3p14 as a candidate tumour suppressor. The LRIG1 gene encodes an integral membrane protein that counteracts signalling by receptor tyrosine kinases belonging to the ERBB family. LRIG1 mRNA and protein are expressed in many tissues, including breast tissue. METHODS: In the present report we analysed the LRIG1 gene by fluorescence in situ hybridisation (FISH), LRIG1 mRNA by quantitative RT-PCR, and LRIG1 protein by western blot analysis. Two tumour series were analysed; one series consisted of 19 tumour samples collected between 1987 and 1995 and the other series consisted of 9 tumour samples with corresponding non-neoplastic breast tissues collected consecutively. RESULTS: The LRIG1 gene showed increased copy number in 11 out of 28 tumours (39%) and only one tumour showed a deletion at this locus. Increased LRIG1 copy number was associated with increased levels of LRIG1 mRNA (two of three tumours) and protein (four of four tumours) in the tumours compared to matched non-neoplastic breast tissue, as assessed by RT-PCR and western blot analysis. CONCLUSION: The molecular function of LRIG1 as a negative regulator of ERBB receptors questions the biological significance of increased LRIG1 copy number in breast cancer. We propose that a common, but hitherto unrecognised, breast cancer linked gene is located within an amplicon containing the LRIG1 locus at 3p14.3

Fuzzy Tandem Repeats Containing p53 Response Elements May Define Species-Specific p53 Target Genes

Evolutionary forces that shape regulatory networks remain poorly understood. In mammals, the Rb pathway is a classic example of species-specific gene regulation, as a germline mutation in one Rb allele promotes retinoblastoma in humans, but not in mice. Here we show that p53 transactivates the Retinoblastoma-like 2 (Rbl2) gene to produce p130 in murine, but not human, cells. We found intronic fuzzy tandem repeats containing perfect p53 response elements to be important for this regulation. We next identified two other murine genes regulated by p53 via fuzzy tandem repeats: Ncoa1 and Klhl26. The repeats are poorly conserved in evolution, and the p53-dependent regulation of the murine genes is lost in humans. Our results indicate a role for the rapid evolution of tandem repeats in shaping differences in p53 regulatory networks between mammalian species

Bayesian Comparison of Neurovascular Coupling Models Using EEG-fMRI

Functional magnetic resonance imaging (fMRI), with blood oxygenation level-dependent (BOLD) contrast, is a widely used technique for studying the human brain. However, it is an indirect measure of underlying neuronal activity and the processes that link this activity to BOLD signals are still a topic of much debate. In order to relate findings from fMRI research to other measures of neuronal activity it is vital to understand the underlying neurovascular coupling mechanism. Currently, there is no consensus on the relative roles of synaptic and spiking activity in the generation of the BOLD response. Here we designed a modelling framework to investigate different neurovascular coupling mechanisms. We use Electroencephalographic (EEG) and fMRI data from a visual stimulation task together with biophysically informed mathematical models describing how neuronal activity generates the BOLD signals. These models allow us to non-invasively infer the degree of local synaptic and spiking activity in the healthy human brain. In addition, we use Bayesian model comparison to decide between neurovascular coupling mechanisms. We show that the BOLD signal is dependent upon both the synaptic and spiking activity but that the relative contributions of these two inputs are dependent upon the underlying neuronal firing rate. When the underlying neuronal firing is low then the BOLD response is best explained by synaptic activity. However, when the neuronal firing rate is high then both synaptic and spiking activity are required to explain the BOLD signal