Carcinoma-associated fibroblasts stimulate tumor progression of initiated human epithelium

The present study demonstrates that fibroblasts associated with carcinomas stimulate tumor progression of initiated nontumorigenic epithelial cells both in an in vivo tissue recombination system and in an in vitro coculture system. Human prostatic carcinoma-associated fibroblasts grown with initiated human prostatic epithelial cells dramatically stimulated growth and altered histology of the epithelial population. This effect was not detected when normal prostatic fibroblasts were grown with the initiated epithelial cells under the same experimental conditions. In contrast, carcinoma-associated fibroblasts did not affect growth of normal human prostatic epithelial cells under identical conditions. From these data, we conclude that in this human prostate cancer model, carcinoma-associated fibroblasts stimulate progression of tumorigenesis. Thus, carcinoma-associated fibroblasts can direct tumor progression of an initiated prostate epithelial cell

The needle in the haystack - searching for genetic and epigenetic differences in monozygotic twins discordant for Tetralogy of Fallot

Congenital heart defects (CHDs) are the most common birth defect in human with an incidence of almost 1% of all live births. Most cases have a multifactorial origin with both genetics and the environment playing a role in its development and progression. Adding an epigenetic component to this aspect is exemplified by monozygotic twins which share the same genetic background but have a different disease status. As a result, the interplay between the genetic, epigenetic and the environmental conditions might contribute to the etiology and phenotype. To date, the underlying causes of the majority of CHDs remain poorly understood. In this study, we performed genome-wide high-throughput sequencing to examine the genetic, structural genomic and epigenetic differences of two identical twin pairs discordant for Tetralogy of Fallot (TOF), representing the most common cyanotic form of CHDs. Our results show the almost identical genetic and structural genomic identity of the twins. In contrast, several epigenetic alterations could be observed given by DNA methylation changes in regulatory regions of known cardiac-relevant genes. Overall, this study provides first insights into the impact of genetic and especially epigenetic factors underlying monozygotic twins discordant for CHD like TOF

Prognostic relevance of number and bilaterality of positive surgical margins after radical prostatectomy

Item does not contain fulltextPURPOSE: Positive surgical margin (PSM) status following radical prostatectomy (RP) is a well-established prognostic factor. The aim of the present study is to evaluate whether number of PSMs or bilaterality of PSMs might have prognostic significance for biochemical recurrence (BCR) in the population with a PSM status following RP. METHODS: We evaluated 1,395 RP pathology reports from our center between 1980 and 2006. All patients who underwent (neo)-adjuvant therapy were excluded, leaving a cohort of 1,009 patients, with 249 (24.7%) subjects having a PSM at RP of whom 29.4% had multiple PSMs (>/= 2 sites), while 13.6% had bilateral PSMs. Median follow-up was 40 months (range 0-258 months). We used BCR-free survival as the primary study outcome. BCR was defined as any rise in PSA above or equal to 0.2 ng/ml. RESULTS: Of patients with a PSM status, 41% (95% CI: 33-49%) developed BCR within 5 years, compared to 12% (95% CI: 9-15%) in the population without a PSM. Multivariable analysis identified PSA at diagnosis and RP Gleason score as independent predictive factors for BCR. Increasing number and/or bilaterality of PSM did not lead to significant higher rates of BCR. CONCLUSION: In patients with a PSM, the number of positive sites or bilaterality of PSM status does not add prognostic information for risk of BCR. Survival curve slopes were different for patients with bilateral PSM, showing a significant tendency to progress to BCR earlier during follow-up than patients with unilateral PSM.1 februari 201

Cytogenetic monoclonality in multifocal uroepithelial carcinomas: evidence of intraluminal tumour seeding

Twenty-one multifocal urinary tract transitional cell carcinomas, mostly bladder tumours, from a total of six patients were processed for cytogenetic analysis after short-term culturing of the tumour cells. Karyotypically related, often identical, cytogenetically complex clones were found in all informative tumours from each case, including the recurrent tumours. Rearrangement of chromosome 9, leading to loss of material from the short and/or the long arm, was seen in all cases, indicating that this is an early, pathogenetically important event in transitional cell carcinogenesis. The presence of related clones with great karyotypic similarity in anatomically distinct tumours from the same bladder indicates that multifocal uroepithelial tumours have a monoclonal origin and arise via intraluminal seeding of viable cancer cells shed from the original tumour. Later lesions may develop also from cells shed from the so called second primary tumours. The relatively complex karyotypes seen in all lesions from most cases argue that the seeding of tumour cells is a late event that succeeds the acquisition by them of multiple secondary genetic abnormalities. © 1999 Cancer Research Campaig

PPARα Deficiency in Inflammatory Cells Suppresses Tumor Growth

Inflammation in the tumor bed can either promote or inhibit tumor growth. Peroxisome proliferator-activated receptor (PPAR)α is a central transcriptional suppressor of inflammation, and may therefore modulate tumor growth. Here we show that PPARα deficiency in the host leads to overt inflammation that suppresses angiogenesis via excess production of the endogenous angiogenesis inhibitor thrombospondin-1 and prevents tumor growth. Bone marrow transplantation and granulocyte depletion show that PPARα expressing granulocytes are necessary for tumor growth. Neutralization of thrombospondin-1 restores tumor growth in PPARα-deficient mice. These findings suggest that the absence of PPARα activity renders inflammatory infiltrates tumor suppressive and, thus, may provide a target for inhibiting tumor growth by modulating stromal processes, such as angiogenesis