73 research outputs found
Microsurgical Lymph Node Dissection for Metastatic Asymptomatic C-Cell Carcinoma
In persistent, clinically inapparent medullary thyroid carcinoma, microsurgical dissection of all lymph node compartments of the neck was performed. Between August 1988 and September 1991, 28 cases (mean age 43.3 years) were treated with 38 surgical interventions. Twenty patients had the sporadic form and eight patients the familial form. Unilateral neck dissection resulted in normalization of serum calcitonin (CT) levels even after pentagastrin stimulation in two patients whereas 16 patients exhibited abnormal CT stimulation tests. Eight of ten patients who had bilateral neck dissections had positive pentagastrin test results after surgery. The main postoperative complications included loss of local cutaneous sensation, generally temporary, and unilateral recurrent laryngeal nerve paralysis
Chemoembolization of the Lung Improves Tumor Control in a Rat Model
ABSTRACT Purpose: The novel method of organ-specific drug application we present here is unilateral chemoembolization of the lung by injecting the pulmonary artery with degradable starch microspheres and cytotoxic drugs to improve tumor control in lung metastases. Experimental Design: In a solitary metastasis rat model (CC531 adenocarcinoma), we studied the clinical and histological tumor response as well as subacute toxicity of the lung. Fourteen days after tumor induction, animals were randomized into five groups. Groups I and II served as controls. Group III received carboplatin i.v. (45 mg/kg). Isolated lung perfusion with buffered starch solution and carboplatin (15 mg/kg) was installed in group IV. Chemoembolization with carboplatin (15 mg/kg) was performed in group V. Results: Seven days later, the difference in the tumor volume before and after treatment was ؉422 mm 3 (؎226) in group I, ؉697 mm 3 (؎423) in group II, ؉70 mm 3 (؎31) in group III, ؊8 mm 3 (؎17) in group IV, and ؊17 mm 3 (؎16) in group V (P < 0.05 groups IV and V versus groups I, II, and III). No pleural spread was observed in groups IV and V. Histologically, the area of tumor necrosis was largest in group IV. Mild alveolar cell hyperplasia, pulmonary edema, and hemorrhage without subacute fibrotic changes were noted in all groups. Conclusion: This is the first study to perform chemoembolization of the lung. Compared with i.v. therapy, chemoembolization was more effective without serious toxicity. Its efficacy was comparable with that of isolated lung perfusion but less stressful for a possible clinical application
T cell responses against tumor associated antigens and prognosis in colorectal cancer patients
INTRODUCTION: Spontaneous T cell responses against specific tumor-associated antigens (TAA) are frequently detected in peripheral blood of tumor patients of various histiotypes. However, little is known about whether these circulating, spontaneously occurring, TAA-reactive T cells influence the clinical course of disease. METHODS: Fifty-four HLA-A2 positive colorectal cancer patients had been analyzed for the presence of T cell responses against epitopes derived from the TAA Ep-CAM, her-2/neu, and CEA either by ELISPOT assay or by intracellular cytokine staining. Then, Kaplan-Meier survival analysis was performed comparing T-cell-responders and T-cell-non-responders. For comparison, a group of T-cell-non-responders was compiled stringently matched to T-cell-responders based on clinical criteria and also analyzed for survival. RESULTS: Sixteen out of 54 patients had a detectable T cell response against at least one of the three tested TAA. Two out of 21 patients (9.5%) with limited stage of disease (UICC I and II) and 14 out of 33 patients (42.4%) with advanced disease (UICC III and IV) were T cell response positive. Comparing all T-cell-responders (n = 16) and all T-cell-non-responders (n = 38), no survival difference was found. In an attempt to reduce the influence of confounding clinical factors, we then compared 16 responders and 16 non-responders in a matched group survival analysis; and again no survival difference was found (p = 0.7). CONCLUSION: In summary, we found no evidence that spontaneous peripheral T cell responses against HLA-A2-binding epitopes of CEA, her-2/neu and Ep-CAM are a strong prognostic factor for survival
A genome-wide map of aberrantly expressed chromosomal islands in colorectal cancer
BACKGROUND: Cancer development is accompanied by genetic phenomena like deletion and amplification of chromosome parts or alterations of chromatin structure. It is expected that these mechanisms have a strong effect on regional gene expression. RESULTS: We investigated genome-wide gene expression in colorectal carcinoma (CRC) and normal epithelial tissues from 25 patients using oligonucleotide arrays. This allowed us to identify 81 distinct chromosomal islands with aberrant gene expression. Of these, 38 islands show a gain in expression and 43 a loss of expression. In total, 7.892 genes (25.3% of all human genes) are located in aberrantly expressed islands. Many chromosomal regions that are linked to hereditary colorectal cancer show deregulated expression. Also, many known tumor genes localize to chromosomal islands of misregulated expression in CRC. CONCLUSION: An extensive comparison with published CGH data suggests that chromosomal regions known for frequent deletions in colon cancer tend to show reduced expression. In contrast, regions that are often amplified in colorectal tumors exhibit heterogeneous expression patterns: even show a decrease of mRNA expression. Because for several islands of deregulated expression chromosomal aberrations have never been observed, we speculate that additional mechanisms (like abnormal states of regional chromatin) also have a substantial impact on the formation of co-expression islands in colorectal carcinoma
Genome-wide expression patterns of invasion front, inner tumor mass and surrounding normal epithelium of colorectal tumors
Colorectal tumors have characteristic genome-wide expression patterns that allow their distinction from normal colon epithelia and facilitate clinical prognosis. The expression heterogeneity within a primary colorectal tumor has not been studied on a genome scale yet. Here we investigated three compartments of colorectal tumors, the invasion front, the inner tumor mass, and surrounding normal epithelial tissue by microdissection and microarray-based expression profiling. In both tumor compartments many genes were differentially expressed when compared to normal epithelium. The sets of significantly deregulated genes in both compartments overlapped to a large extent and revealed various interesting known and novel pathways that could have contributed to tumorigenesis. Cells from the invasion front and inner tumor mass, however, did not show significant differences in their expression profile, neither on the single gene level nor on the pathway level. Instead, gene expression differences between individuals are more pronounced as all patient-matched tumor samples clustered in close proximity to each other. With respect to invasion front and inner tumor mass we conclude that the specific tumor cell micro-environment does not have a strong influence on expression patterns: largely similar genome-wide expression programs operate in the invasion front and interior compartment of a colorectal tumor
An expression module of WIPF1-coexpressed genes identifies patients with favorable prognosis in three tumor types
Wiskott–Aldrich syndrome (WAS) predisposes patients to leukemia and lymphoma. WAS is caused by mutations in the protein WASP which impair its interaction with the WIPF1 protein. Here, we aim to identify a module of WIPF1-coexpressed genes and to assess its use as a prognostic signature for colorectal cancer, glioma, and breast cancer patients. Two public colorectal cancer microarray data sets were used for discovery and validation of the WIPF1 co-expression module. Based on expression of the WIPF1 signature, we classified more than 400 additional tumors with microarray data from our own experiments or from publicly available data sets according to their WIPF1 signature expression. This allowed us to separate patient populations for colorectal cancers, breast cancers, and gliomas for which clinical characteristics like survival times and times to relapse were analyzed. Groups of colorectal cancer, breast cancer, and glioma patients with low expression of the WIPF1 co-expression module generally had a favorable prognosis. In addition, the majority of WIPF1 signature genes are individually correlated with disease outcome in different studies. Literature gene network analysis revealed that among WIPF1 co-expressed genes known direct transcriptional targets of c-myc, ESR1 and p53 are enriched. The mean expression profile of WIPF1 signature genes is correlated with the profile of a proliferation signature. The WIPF1 signature is the first microarray-based prognostic expression signature primarily developed for colorectal cancer that is instrumental in other tumor types: low expression of the WIPF1 module is associated with better prognosis
Effect of Network Architecture on Synchronization and Entrainment Properties of the Circadian Oscillations in the Suprachiasmatic Nucleus
In mammals, the suprachiasmatic nucleus (SCN) of the hypothalamus constitutes the central circadian pacemaker. The SCN receives light signals from the retina and controls peripheral circadian clocks (located in the cortex, the pineal gland, the liver, the kidney, the heart, etc.). This hierarchical organization of the circadian system ensures the proper timing of physiological processes. In each SCN neuron, interconnected transcriptional and translational feedback loops enable the circadian expression of the clock genes. Although all the neurons have the same genotype, the oscillations of individual cells are highly heterogeneous in dispersed cell culture: many cells present damped oscillations and the period of the oscillations varies from cell to cell. In addition, the neurotransmitters that ensure the intercellular coupling, and thereby the synchronization of the cellular rhythms, differ between the two main regions of the SCN. In this work, a mathematical model that accounts for this heterogeneous organization of the SCN is presented and used to study the implication of the SCN network topology on synchronization and entrainment properties. The results show that oscillations with larger amplitude can be obtained with scale-free networks, in contrast to random and local connections. Networks with the small-world property such as the scale-free networks used in this work can adapt faster to a delay or advance in the light/dark cycle (jet lag). Interestingly a certain level of cellular heterogeneity is not detrimental to synchronization performances, but on the contrary helps resynchronization after jet lag. When coupling two networks with different topologies that mimic the two regions of the SCN, efficient filtering of pulse-like perturbations in the entrainment pattern is observed. These results suggest that the complex and heterogeneous architecture of the SCN decreases the sensitivity of the network to short entrainment perturbations while, at the same time, improving its adaptation abilities to long term changes
Postoperative Pentagastrin-Stimulated Serum Calcitonin Concentrations in Patients with Medullary Thyroid Carcinoma: Reoperations in Patients with Concentrations Bordering the Detection Limit
The case reports on two patients with medullary thyroid carcinoma show that even postoperatively stimulated serum calcitonin (CT) concentrations near the detection limit (using a polyclonal antibody against synthetic CT) can demonstrate persistent disease. Stimulated CT concentrations can be lowered to nondetectable levels by a second and third operation if a meticulous technique is used for dissection of the lymph compartments. The patient can then be assumed lo be cured. Diagnostic accuracy at very low CT concentrations can be improved by selective venous catheterization with blood sampling for CT after stimulation
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