Biomedical subjects

R Metzger

Publications and source records attributed to R Metzger.

At least 19 recordsLinked to original sources

PubMed2002

Management of the primary obstructed megaureter (POM) and indication for operative treatment.

Presented is the diagnostic and therapeutic management of the primary obstructed megaureter (POM). 42 patients presented with 53 ureteral units (UU) of POM (5 females, 37 males, 36 neonates and 6 children aged 3 to 8 years). Of the 53 megaureters 10 UU (19%) were on the right and 27 UU(51 %)were on the left. 8 patients (19%)with 16 UU (30%)showed a bilateral abnormality. In 41% of the patients, hydronephrosis had been discovered by prenatal ultrasound. All patients were evaluated postnatally by ultrasound (US), voiding cysturethrogram (VCUG), intravenous pyelogram (IVP) and diuresis renogram (MAG-3) (DR). Due to the percentage of urinary drainage,the renogram results were classified into different categories:no obstruction, functional obstruction, equivocal and obstruction. A partial renal function was also calculated. Follow-up of the patients ranges between 5 to 48 months (mean: 22.1). All patients underwent serial US and serial DR were obtained in 36 patients. Initially, 9 (17%) UU showed a functional obstruction, 34 (64.2%) an equivocal and 10 (18.8%) an obstructive urinary drainage pattern. 2 kidneys showed a significant decreased partial function of 20, respectively 26%. Surgery was performed in an initial im-paired renal function with an obstructive pattern or in cases with normal function and at least equivocal urinary drainage pattern with no improvement or deterioration of the urinary drainage and/or function in the follow-up. Considering these criteria, 5(9.6%) patients needed surgery. No loss of kidney function has been observed in follow-up. DR is the most valuable diagnostic tool. Criteria interpreting the results are demonstrated in this article.

Child↗

PubMed2001

Loss of expression of HDAC-recruiting methyl-CpG-binding domain proteins in human cancer.

Dysregulation of CpG-methylation is a common feature of many human cancers and tumour suppressor genes can be silenced by hypermethylation. Recently, 2 methyl-CpG-binding domain proteins have been linked to gene inactivation by their ability to recruit co-repressors and HDAC-activity to methylated gene promoters. Here, we have analysed mRNA expression of these genes, MeCP2 and MBD2, in a wide variety of primary human tumours. In solid tumours, expression levels of MBD2 (57/71) and MeCP2 (64/71) were significantly reduced in the majority of primary tumours as detected by quantitative real-time RT-PCR. Western blot analyses of MeCP2 in matched tumour-normal samples of patients with non-small-cell lung cancer (NSCLC) indicated reduced protein in a significant percentage of patients. In acute myelogenous leukaemia (n = 26), expression levels were only slightly reduced and did not differ between samples analysed at diagnosis or at the time of relapse. In early-stage NSCLC (n = 70) expression of MeCP2 and MBD2 was significantly lower in squamous cell carcinoma than in adenocarcinoma or large cell carcinoma (P = 0.03 and P = 0.01). To further elucidate the mechanisms of gene regulation, we analysed MeCP2 and MBD2 regulation during haematopoietic differentiation. No significant changes in MeCP2 or MBD2 expression were found when NB4 cells were differentiated toward granulocytes suggesting that neither differentiation nor cell cycle status were relevant for the reduced expression of these genes in human cancer. In conclusion, the significant loss of MeCP2 and MBD2 expression in human cancers suggests a potential role of this phenomenon in the development of solid human tumours.

Cell Differentiation↗

PubMed2001

Towards in-vitro prediction of an in-vivo cytostatic response of human tumor cells with a fast chemosensitivity assay.

The objective of this study is to evaluate a novel approach to chemosensitivity testing with respect to its predictive value in the selection of clinically effective cytostatic drugs to optimize the therapeutic treatment of cancer. The chemosensitivity assay, which we used in this study, has its roots in pharmaceutical drug screening and the surrounding intellectual property is protected by various patent applications and trademarks. Therefore, we will refer to this test in the following pages as ChemoSelect. ChemoSelect is a sensor-chip based diagnostic test, which permits the functional and continuous real-time measurement of induced tumor cell cytotoxicity following the administration of chemotherapeutic drugs. Chemosensitivity is measured through the reduction of the excretion of lactic and carbonic acids--by-products of the metabolic processes of glycolysis and respiration and a parameter for cell vitality--generated specifically by ATP hydrolysis and lactic acid production. We used this test to study the applicability of this assay for tumor cells based on the analysis of tumor cell lines and tumor specimens. In this preliminary study, this test was studied in predicting chemoresistance and chemosensitivity in cell lines and tumor specimens for which the result was already predetermined by the properties of the cell line or the tumor specimen used in the experiment. The applicability in a clinical setting was studied by confirming the trends on selected drug sensitivity and drug resistance with an interim analysis of an ongoing clinical study in selected patients with breast cancer undergoing neoadjuvant chemotherapy. The minimum detection limit of cells and biologic cell responses, an important variable determining the applicability of the test in routine clinical use, was also assessed. ChemoSelect avoids many of the limitations of existing chemoresistance assays and provides more comprehensive information and output, as it has a 24-h turnaround time, is applicable to the majority of solid tumors and available cytostatic drugs, does not need more than 10(5) cells in total, cultivated tumor cells, provides dynamic monitoring of cellular responses through on-line data read-out during the perfusion with drugs and can be extended to the analysis of novel therapeutic modalities such as biologics.

Antineoplastic Agents↗

PubMed2001

Randomized trial of tacrolimus plus mycophenolate mofetil or azathioprine versus cyclosporine oral solution (modified) plus mycophenolate mofetil after cadaveric kidney transplantation: results at 2 years.

BACKGROUND: A previous report described the 1-year results of a prospective, randomized trial designed to investigate the optimal combination of immunosuppressants in kidney transplantation. Recipients of first cadaveric kidney allografts were treated with tacrolimus+mycophenolate mofetil (MMF), cyclosporine oral solution (modified) (CsA)+MMF, or tacrolimus+azathioprine (AZA). Results at 1 year revealed that optimal efficacy and safety were achieved with a regimen containing tacrolimus+MMF. The present report describes results at 2 years. METHODS: Two hundred twenty-three recipients of first cadaveric kidney allografts were randomized to receive tacrolimus+MMF, CsA+MMF, or tacrolimus+AZA. All regimens contained corticosteroids, and antibody induction was used only in patients who experienced delayed graft function. Patients were followed up for 2 years. RESULTS: The results at 2 years corroborate and extend the findings of the previous report. Patients randomized to either treatment arm containing tacrolimus experienced improved kidney function. New-onset insulin dependence remained in four, three, and four patients in the tacrolimus+MMF, CsA+MMF, and tacrolimus+AZA treatment arms, respectively. Furthermore, patients with delayed graft function/acute tubular necrosis who were treated with tacrolimus+MMF experienced a 23% increase in allograft survival compared with patients receiving CsA+MMF (P=0.06). Patients randomized to tacrolimus+MMF received significantly lower doses of MMF compared with those administered CsA+MMF. CONCLUSIONS: All three immunosuppressive regi-mens provided excellent safety and efficacy. How-ever, the best results overall were achieved with tacrolimus+MMF. The combination may provide particular benefit to kidney allograft recipients who develop delayed graft function/acute tubular necrosis. Renal function at 2 years was better in the tacrolimus treatment groups compared with the CsA group.

Administration, Oral↗

PubMed2001

Adenomatous polyposis coli gene promoter hypermethylation in non-small cell lung cancer is associated with survival.

Methylation of 5' CpG islands in promoter and upstream coding regions has been identified as a mechanism for transcriptional inactivation of tumor suppressor genes. The purpose of this study was to determine whether hypermethylation of the adenomatous polyposis coli (APC) gene promoter occurs in primary non-small cell lung cancer (NSCLC), and whether hypermethylated APC has any relationship with survival. APC promoter 1A methylation was determined in normal and corresponding tumor tissue from 91 NSCLC patients and in a control group of 10 patients without cancer, using a quantitative fluorogenic real-time PCR (Taqman) system. APC promoter methylation was detectable in 86 (95%) of 91 tumor samples, but also in 80 (88%) of 91 normal samples of NSCLC patients, and in only two (20%) of 10 normal lung tissues of the control group. The median level of APC promoter methylation was 4.75 in tumor compared to 1.57 in normal lung tissue (P<0.001). Patients with low methylation status showed significantly longer survival than did patients with high methylation status (P=0.041). In a multivariate analysis of prognostic factors, APC methylation was a significant independent prognostic factor (P=0.044), as were pT (P=0.050) and pN (P<0.001) classifications. This investigation shows that APC gene promoter methylation occurs in the majority of primary NSCLCs. High APC promoter methylation is significantly associated with inferior survival, showing promise as a biomarker of biologically aggressive disease in NSCLC.

Adenocarcinoma↗

PubMed2001

Cyclin E is the only cyclin-dependent kinase 2-associated cyclin that predicts metastasis and survival in early stage non-small cell lung cancer.

Progression through G1-S transition and S phase of the cell cycle is mediated by cyclin-dependent kinase 2 (cdk2), which interacts with several cyclins. Two of these, cyclin E and cyclin A2 (also known as cyclin A), are overexpressed in many cancers. Cyclin E2 and cyclin A1 are recently discovered cdk2-interacting cyclins that are found in malignant tumor cell lines and in acute myeloid leukemia, respectively. Expression and prognostic role of these cyclins in solid tumors is unknown. Here, we have analyzed expression and prognostic relevance of the cdk2-associated cyclins in non-small cell lung cancer (NSCLC). Fresh-frozen biopsies (n = 70) from completely resected tumors with stage I to IIIA NSCLC were studied. Gene expression was analyzed by quantitative real-time reverse transcription-PCR. Expression levels of cyclin E (P = 0.04) and cyclin A2 (P = 0.004) were significantly higher in the tumor samples than in normal controls. Cyclin A1, cyclin A2, and cyclin E2 expression levels did not have prognostic relevance for survival. The mean survival time associated with low and high levels of cyclin E was 69.4 and 47.2 months, respectively, which was statistically significant (P = 0.03). Differences in survival were particularly pronounced in stages I and II. Cyclin E was also closely associated with the development of distant metastasis (P = 0.01). Finally, we confirmed by immunohistochemistry analyses that cyclin E mRNA expression was closely associated with cyclin E protein expression. In conclusion, cyclin E is a strong independent prognostic indicator in patients with early-stage NSCLC, whereas cyclin E2, cyclin A1, and cyclin A2 do not have a prognostic role in NSCLC.

Adult↗

PubMed2001

Increased c-myb mRNA expression in Barrett's esophagus and Barrett's-associated adenocarcinoma.

BACKGROUND: Esophageal adenocarcinoma develops through a multistage process which is characterized histopathologically by progression from Barrett's intestinal metaplasia to Barrett's esophagus with dysplasia and ultimately to adenocarcinoma. The genetic basis of this process is increasingly well understood, but no studies have examined the role of the transcription factor c-myb in this disease. MATERIALS AND METHODS: c-myb mRNA expression levels were measured using a quantitative reverse transcription-polymerase chain reaction (RT-PCR) method in specimens of Barrett's intestinal metaplasia (n = 16), adenocarcinoma (n = 22), matching normal squamous esophagus tissues (n = 38), and normal squamous esophagus tissues from patients without Barrett's esophagus or chronic gastroesophageal reflux disease (n = 10). RESULTS: The median c-myb mRNA expression levels were significantly increased in Barrett's intestinal metaplasia tissues compared to normal esophagus tissues (P = 0.013) and in Barrett's-associated adenocarcinoma tissues compared to normal squamous esophagus tissues (P = 0.001). The c-myb expression levels increased progressively and significantly in histopathologically worse tissue types, with an increase from normal squamous esophagus mucosa to Barrett's intestinal metaplasia, and from Barrett's intestinal metaplasia to adenocarcinoma of the esophagus (P = 0.002). Median c-myb expression levels were also significantly higher in histologically normal squamous esophagus tissues from cancer patients compared to normal esophagus tissues from patients without cancer (P < 0.001) and a control group without evidence of Barrett's esophagus or gastroesophageal reflux disease (P = 0.003). Very high c-myb mRNA expression levels were found only in patients with cancer. CONCLUSION: These findings suggest that upregulation of c-myb mRNA expression is an early event in the development of Barrett's esophagus and associated adenocarcinoma, that high c-myb mRNA expression levels may be a clinically useful biomarker for the detection of occult adenocarcinoma, and that a widespread cancer "field" effect is present in the esophagus of patients with Barrett's-associated adenocarcinoma.

Adenocarcinoma↗

PubMed2001

Coincidence of nutritional habits and esophageal cancer in Germany.

INTRODUCTION: The incidence rates for adenocarcinoma (AC) of the esophagus have risen rapidly in Western nations, whereas the incidence rates for esophageal squamous cell carcinoma (SCC) have remained nearly stable. There are studies about body mass index, smoking, alcohol, and development of AC or SCC. The aim of this study was to evaluate differences in nutritional habits of patients with AC or SCC compared with the population in Cologne. PATIENTS AND METHODS: From January 1, 1997 to December 31, 1998, 85 patients with esophageal cancer (SCC n = 45, AC n = 40) were interviewed about their nutritional habits using a computerized program (EBIS). By random sample, 100 citizens of Cologne who were similar of age, residence, and nationality were chosen as healthy control group (CG) and were also interviewed with EBIS. RESULTS: The known risk factors, alcohol and tobacco for SCC as well as alcohol and a high body mass index for AC, were confirmed in this study. The CG had a higher daily intake of calcium, magnesium and iron compared to patients with esophageal cancer (p < 0.05). In addition, the tumor group had a significant lower daily supply of carbohydrates, fruits, and dietary fiber (p < 0.001). About 80% of the patients ate more than 100 g meat/day in comparison to 50% of participants in the CG. Patients with AC consumed more magnesium, milk, and animal protein than patients with SCC or the participants of the CG. CONCLUSION: There are differences in nutrition between healthy controls and patients with esophageal cancer and between patients with SCC and AC. Patients with cancer of the esophagus had a nutritonal deficit in fresh fruit, vegetables, dietary fiber, and carbohydrates. Compared with the other groups, patients with AC had a higher intake of protein, fat, and milk.

Adenocarcinoma↗

PubMed2001

Epidermal growth factor receptor and HER2-neu mRNA expression in non-small cell lung cancer Is correlated with survival.

The prognostic role of epidermal growth factor receptor (EGFR) and HER2-neu remains controversial in patients with non-small cell lung cancer (NSCLC). We studied the association between the mRNA expression of EGFR, HER2-neu, and survival in primary tumor and matching nonmalignant tissues from 83 patients with NSCLC. Analysis was performed using a quantitative real-time PCR system (Taqman). EGFR and HER2-neu mRNA expression was detectable in all (100%) specimens analyzed. Twenty-nine (34.9%) patients had high HER2-neu expression, and 28 (33.7%) patients had high EGFR expression. A high HER2-neu and EGFR coexpression was detectable in 14 (16.9%) patients. High HER2-neu expression was associated with inferior survival (P = 0.004), whereas high EGFR expression showed a trend toward inferior survival (P = 0.176). The impact of HER2-neu and EGFR coexpression on patients' survival was additive (P = 0.003). Multivariate analysis determined high HER2-neu expression (P = 0.041), and high EGFR/HER2-neu coexpression (P = 0.030) as significant and independent unfavorable prognostic factors. These findings indicate that HER2-neu and EGFR play a crucial role in the biological behavior of NSCLCs. Testing of molecular marker coexpression (EGFR and HER2-neu) improves the estimation of prognosis and appears to define low- and high-risk groups for treatment failure in curatively resected NSCLC.

Adult↗

PubMed2000

In vitro toxicology in hepatocyte bioreactors-extracellular acidification rate (EAR) in a target cell line indicates hepato-activated transformation of substrates.

In this article we introduce an in vitro model for hepato-mediated toxicity testing consisting of a Hepatocyte-Bioreactor connected to a microphysiometer system for monitoring of the extracellular acidification rate (EAR) of cells. The EAR in this system represented the metabolic activity of a tested cell line under the influence of bioreactor supernatant. Cyclophosphamide (CYCL), a well-known hepato-activated cytostatic drug was used as a model substrate because of its widespread clinical use. The predrug CYCL needed CYP 450 dependent activation to its active cytotoxic metabolite 4-OH cyclophosphamide. Primary pig hepatocytes from slaughterhouse organs were cultured in a collagen sandwich configuration in specially designed flasks and after 3 days introduced into a 50 ml recirculating perfusion system including 30 microg/ml CYCL. In a parallel open circuit, this bioreactor was connected to three perfusion chambers of a microphysiometer system housing 1.5 x 10(5) ZR 751 cells (breast tumor cell line). Bioreactor supernatant including CYCL was pumped at 150 microl/min into the microphysiometer. The recorded EARs under CYCL influence were correlated to controls, which were set to be 100%. After 1 and 7 h of bioreactor supernatant perfusion, including activated CYCL, the ZR 751 cell line showed an EAR of 98.99%+/-3.15 (mean+/-SD) and 81. 32%+/-10.18 (P<0.05), respectively, as compared to controls (bioreactor supernatant from the identical set-up without CYCL). The inactivated predrug CYCL showed no effect on the EAR: Perfusion of medium with 30 microg/ml CYCL alone, excluding the bioreactor activation, resulted in an EAR of 100. 11%+/-4.74 (mean+/-SD) after 7 h. Thus the presented model of hepato-activated toxicity showed an EAR decrease in the ZR 751 cell line that reflected the toxic activation of the predrug by the bioreactor.

Albumins↗

PubMed2000

Randomized trial of tacrolimus (Prograf) in combination with azathioprine or mycophenolate mofetil versus cyclosporine (Neoral) with mycophenolate mofetil after cadaveric kidney transplantation.

BACKGROUND: Our clinical trial was designed to investigate the optimal combination of immunosuppressants for renal transplantation. METHODS: A randomized three-arm, parallel group, open label, prospective study was performed at 15 North American centers to compare three immunosuppressive regimens: tacrolimus + azathioprine (AZA) versus cyclosporine (Neoral) + mycophenolate mofetil (MMF) versus tacrolimus + MMF. All patients were first cadaveric kidney transplants receiving the same maintenance corticosteroid regimen. Only patients with delayed graft function (32%) received antilymphocyte induction. A total of 223 patients were randomized, transplanted, and followed for 1 year. RESULTS: There were no significant differences in baseline demography between the three treatment groups. At 1 year the results are as follows: acute rejection 17% (95% confidence interval 9%, 26%) in tacrolimus + AZA; 20% (confidence interval 11%, 29%) in cyclosporine + MMF; and 15% (confidence interval 7%, 24%) in tacrolimus + MMF. The incidence of steroid resistant rejection requiring antilymphocyte therapy was 12% in the tacrolimus + AZA group, 11% in the cyclosporine + MMF group, and 4% in the tacrolimus + MMF group. There were no significant differences in overall patient or graft survival. Tacrolimus-treated patients had a lower incidence of hyperlipidemia through 6 months posttransplant. The incidence of posttransplant diabetes mellitus requiring insulin was 14% in the tacrolimus + AZA group, 7% in the cyclosporine + MMF and 7% in the tacrolimus + MMF groups. CONCLUSIONS: All regimens yielded similar acute rejection rates and graft survival, but the tacrolimus + MMF regimen was associated with the lowest rate of steroid resistant rejection requiring antilymphocyte therapy.

Adult↗

PubMed2000

Organ-specific distribution of major histocompatibility antigens in rats.

The present study systematically investigated the expression and distribution of the major histocompatibility complex (MHC) classes I and II in the rat. About 150 native tissue probes from eight adult Lewis rats were taken, representative for most organs, tissues, and the vascular system. MHC expression was analyzed by two monoclonal antibodies (mAb) generated against the non-polymorphic determinants of rat MHC class I (Ox-18) and class II (Ox-6). Immunoreactivities were compared to those of different endothelial (HIS52, TLD-3A12, Ox-43, REHA-1 antigen), histiocytic (ED1, ED2), B-cell (RLN-9D3), and T-cell (MRC Ox-52) markers. A nonspecific mAb (MR12/53) served as a negative control. Pretested concentrations on various tissues and the alkaline phosphatase-anti-alkaline phosphatase technique allowed semiquantitative evaluation of serial cryostat tissue sections. MHC class I expression was detected on most immunocompetent cells. Endothelial cells were stained heterogeneously along the vascular system and the organ-specific microcirculation. Furthermore, some organs showed staining of parenchymal cells. MHC class II was found on all immunocompetent cells positive for the B-cell marker and about 15% of cells positive for the histiocytic markers. Besides the well-known expression of MHC class II in the outer zone of the renal proximal tubule, further organ-specific cell forms were found positive. In conclusion, the present study outlines tissue-specific distribution of MHC I/ II and implies that each organ carries a variable immunologic burden that needs to be considered for any transplantation model.

Adrenal Cortex↗

PubMed2000

Proliferation, zonal maturation, and steroid production of fetal adrenal transplants in adrenalectomized rats.

The present study investigated the histologic maturation, proliferative capacity, and steroid production of fetal adrenal transplants (Tx) in adrenalectomized rats. A pair of fetal adrenal glands (18-20 days of gestation) was transplanted into the omentum of syngeneic Lewis rats (n = 45). Four weeks later, in 5 animals the grafts were excised for morphologic evaluation. Proliferation was investigated by immunohistochemical staining for KI-67 protein and quantified by the proliferation index (PI = positive cells/100 counts). All other hosts (Tx; n = 40) underwent bilateral adrenalectomy (AE) to induce Addisonian crisis. Postoperatively, survival and concentrations of potassium, sodium, aldosterone, and corticosterone were recorded for 6 months. These data were compared to controls (C=only AE; n = 30) and a sham group (S; n = 10). At the end of the study period all surviving hosts were killed for histologic examination of grafts. At 4 weeks post-Tx the adrenal grafts demonstrated a distinct zona glomerulosa and frequent proliferation with a PI of 0.084, comparable to normal control (0.092). Following AE survival was significantly prolonged in Tx (86% vs 12% of C, P < 0.05). Control animals developed severe hyponatremia and hyperkalemia, whereas in Tx only transient signs of Addisonian crisis were recorded. Levels of aldosterone dropped within 7 days in the Tx and C groups, but returned to normal for Tx within 8 weeks. Corticosterone levels of Tx animals fell to 25% within week, but steadily increased to 70% by the end of the study. At 6 months, grafts revealed a mature adrenocortical structure with little proliferative activity, which was comparable to controls. In a syngeneic rat model fetal adrenal transplants thus mature and proliferate to provide sufficient steroid production for adrenalectomized hosts.

Adrenal Glands↗

PubMed2000

CD143 in the development of atherosclerosis.

The expression of CD143 (angiotensin-I-converting enzyme, ACE) in cardiovascular diseases may be an important determinant of local angiotensin and kinin concentrations. Much of the experimental and clinical evidence suggests a crucial role for Ang II in fibrogenesis and the development of atherosclerosis. Therefore, we have studied the distribution of CD143 in atherosclerotic and non-atherosclerotic segments isolated from different parts of the human vascular tree, including aorta and coronary, carotid, brachial, renal, iliac and femoral arteries, and staged according to the AHA. Two hundred and thirty native and formalin-fixed specimens of 80 patients were analysed by sensitive APAAP-technique using ten different monoclonal and polyclonal antibodies to human CD143 and several controls. In non-atherosclerotic segments or intimal thickening, CD143 was found almost restricted to the endothelial cells of adventitial arterioles and small muscular arteries. In contrast, a striking accumulation of CD143 was detected in all early and advanced atherosclerotic lesions. This de-novo occurrence of CD143 within the intimal vascular wall was caused by spindle-shaped subendothelial cells with macrophagic/histocytic features, activated macrophages and foam cells. In addition, advanced lesions of atherosclerosis showed a marked neo-expression of CD143 in newly formed intimal microvessels. Hypocellular fibrotic plaques depleted in microvessels and macrophages showed only little CD143. The de-novo occurrence of CD143 was dependent on the stage of atherosclerosis but not on its particular localisation within the vascular system. This early and obligatory CD143 expression at an unusual vascular site may contribute to unusual tissue levels of angiotensins as indicated by co-localisation of immunoreactive Ang II. Thus, it may be an important pathogenetic step in the development of atherosclerosis and an established target for pharmacological prevention.

Adolescent↗

PubMed2000

Somatic isoform of angiotensin I-converting enzyme in the pathology of testicular germ cell tumors.

Retained fetal expression of angiotensin I-converting enzyme (ACE, CD143) has recently been shown in intratubular germ cell neoplasms (IGCN) and invasive germ cell tumors (GCT), suggesting the somatic isoform (sACE) as a characteristic component of neoplastic germ cells. We analyzed the distribution of sACE in 159 testicular GCT, including 87 IGCN. sACE protein was determined by immunohistochemistry (MAb CG2) on routinely formalin-fixed and paraffin-embedded tissue sections, supplemented by mRNA expression analysis using in situ hybridization. These data were compared with those obtained by germ cell/placental alkaline phosphatases (PIAP; MAbs PL8-F6 and 8A9) employing an uniform score system for the evaluation of immunoreactivity (IRS; possible values from 0 to 12). Expression of sACE and PIAP was found in all 87 analyzed IGCN (IRS > 4, median IRS of 12). Heterogeneous staining patterns were not related to the type of adjacent GCT but correlated with low expression in adjacent seminomas (P =.032 for sACE; P =.005 for PIAP). Both sACE and PIAP often showed a decreased and more heterogeneous but still moderate expression in 91 classic seminomas (median IRS of 8) and were completely absent in tumor cells of spermatocytic seminomas. Despite all similarities, we found sACE and PIAP differently regulated during GCT progression. This was documented by a well-preserved expression of either sACE or PIAP or both in all classic seminomas, low PIAP immunoreactivity in metastasis of seminomas, and completely diverging expression patterns in nonseminomatous GCT. Our findings underline the close molecular relationship between IGCN and seminoma, and suggest sACE as an appropriate marker for seminomatous differentiated tumors. HUM PATHOL 31:1466-1476.

Adolescent↗

PubMed2000

Multiple molecular marker testing (p53, C-Ki-ras, c-erbB-2) improves estimation of prognosis in potentially curative resected non-small cell lung cancer.

A prospective study was performed in patients with non-small cell lung cancer (NSCLC) to evaluate the prognostic importance of multiple molecular marker (p53, c-Ki-ras, c-erbB-2) testing. 103 patients with potentially curative resections (RO resection) for NSCLC in histopathological stages I-IIIA were included. SSCP analysis and DNA sequencing for p53 and c-Ki-ras genes were performed on paired tumour and normal lung tissue samples and immunohistochemistry (c-erbB-2) was done on frozen tissue sections with a specific anti-c-erbB-2 monoclonal antibody. 46/103 (44.6%) NSCLC showed p53 mutations and 17/103 (16.5%) c-Ki-ras mutations including 12/37 (32.4%) adenocarcinomas. Overexpression of c-erbB-2 (p185) was detected in 56/103 (54.4%) tumours. 24/103 (23.3%) NSCLC were negative for alterations in all 3 parameters (c-Ki-ras, p53 and p185) whereas 79/103 (76.7%) were positive for at least one of the 3 parameters. In a regression model including a multiple molecular marker parameter (negative for all 3 markers versus positive for at least one marker), histopathological stage (P<0.00001), respectively the pT (P<0.01) and pN (P<0.00001) categories and the multiple molecular marker parameter (P<0.01) were of significant prognostic importance. This study demonstrates that testing 3 molecular markers (c-Ki-ras, p53 and c-erbB-2) improves estimation of prognosis compared to single marker testing and appears to define low (82.6%+/-7.9% 5-year survival) and high risk (40.2%+/-5.5% 5-year survival) groups for treatment failure in potentially curative (RO) resected NSCLC.

Adult↗

PubMed2000

Colorectal tumors responding to 5-fluorouracil have low gene expression levels of dihydropyrimidine dehydrogenase, thymidylate synthase, and thymidine phosphorylase.

We had previously shown that high gene expressions (mRNA levels) of thymidylate synthase (TS; Leichman et al., J. Clin. Oncol., 15: 3223-3229, 1997) and thymidine phosphorylase (TP; Metzger et al., Clin. Cancer Res., 4: 2371-2376, 1998) in pretreatment tumor biopsies could identify tumors that would be nonresponsive to 5-fluorouracil (5-FU)-based therapy. In this study, we investigated the association between intratumoral gene expression of the pyrimidine catabolism enzyme dihydropyrimidine dehydrogenase (DPD) and the response of colorectal tumors to the same 5-FU-based protocol. DPD expressions were measured by quantitative reverse transcription-PCR in 33 pretreatment biopsies of colorectal tumors from patients who went on to receive treatment with 5-FU and leucovorin (LV). The range of DPD gene expression in those tumors that were nonresponsive to 5-FU was much broader than that of the responding tumors. None of the tumors with basal-level DPD expressions above a DPD:beta-actin ratio of 2.5 x 10(-3) (14 of 33) were responders to 5-FU/LV therapy, whereas those tumors with DPD gene expressions below DPD: beta-actin ratio of 2.5 x 10(-3) had a response rate of 50%. There was no correlation among DPD, TS, and TP expression values in this set of colorectal tumors, which indicated that these gene expressions are independent variables. All of the tumors that responded to 5-FU therapy (11 of 33) had expression values of all three of the genes, TS, TP, and DPD, below their respective nonresponse cutoff values, whereas, in each of the nonresponding tumors, at least one of these gene expressions was high. The patients with low expression of all three of the genes had significantly longer survival than patients with a high value of any one of the gene expressions. The results of this study show that intratumoral gene expression level of DPD is associated with tumor response to 5-FU and that the use of more than one independent determinant of response permits the identification of a high percentage of responding patients.

Antimetabolites, Antineoplastic↗

PubMed2000

[Preoperative radiochemotherapy of esophageal carcinoma. Light at the end of the tunnel?].

Studies on neoadjuvant therapy of esophageal cancer showed that not either preoperative chemotherapy or radiotherapy lead to a significant improvement of prognosis. However, two prospective studies showed a significant prognostic improvement after neoadjuvant combined radio/chemotherapy. Most treatment protocols include a radiation with 30-45 Gy and a simultaneous therapy with Cis-Platin/5-Fluorouracil. As an increase of perioperative morbidity and mortality has to be expected through this treatment, a careful selection of patients is necessary. Several studies have shown that mostly patients with good response benefit from this neoadjuvant therapy. The clinical response evaluation is difficult and response is best proved by classification of the histomorphologic regression of the tumor. For future research, predictive response analyses based on molecular biologic and immuno-histochemic techniques are of great importance and first differentiations by biomarkers have been detected.

Adenocarcinoma↗