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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An in vitro model has been devised so that mixtures of human tumor cells can be grown together for studies related to drug-induced or -selected changes in sensitivity. In the studies reported here, two human astrocytoma clones, one sensitive and one resistant to 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea (MeCCNU), were carefully matched for doubling times, cell cycle phase distributions, and colony-forming efficiencies. The clones were mixed and grown together, and after only three weekly treatments with MeCCNU (10 micrograms/ml for 1 h each week) the sensitive cells in the mixture were killed, leaving behind a population that was almost 100% resistant to further exposures to MeCCNU. The loss of the sensitive cells from the mixture each week was easily detected by visual observation of flow microfluorometry histograms since the clones had different DNA indices. Repeated weekly exposures of the unmixed resistant clone (AST 1-1) to MeCCNU caused very little accumulated cell kill. Similar exposures of the unmixed sensitive clone (AST 3-4) produced a linear decrease in survival over the first three weekly treatments with 10 micrograms MeCCNU/ml, but after that time these cells became progressively more resistant to MeCCNU. It is unlikely that the change to resistance in the AST 3-4 clone occurred because of contamination with the resistant AST 1-1 cells, because their DNA index remained stable. These data show that repeated treatments with a single agent can cause a tumor cell population to become more resistant. It remains to be tested whether this resistance was the result of cellular interactions, drug-induced changes in sensitivity, or selection for resistant cells already present in the populations. This mixture model may be useful in studies on how cellular interactions influence growth and drug sensitivity in tumor and normal cell populations.
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PMID:Treatment-induced changes in sensitivity in a multiclonal human tumor mixture model in vitro. 335 35

The effect of fish treated with gamma-beams on the animal body on the whole and on some organs and tissues was studied in chronic experiments on 4 generations of Wistar rats of both sexes. The animals' status was evaluated according to the rats' appearance, behavior, and the time-course of changes in the body weight. In rats of the basic generation, the rate of tumor occurrence and tumor sites were also examined. Morphological and biochemical investigations were carried out over time, namely after 4, 8, 12 and 17 months. The measurements were taken of blood serum and liver proteins, blood sulfhydryl groups and hemoglobin, ascorbic acid in the liver and adrenals, as well as of the activity of AST, ALT and cholinesterase in the blood serum and in the liver. In the majority of cases, the findings obtained in experimental animals did not differ from those in controls.
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PMID:[Toxicological evaluation of gamma ray-treated fresh fish in an experiment on rats]. 406 Jun 88

The present work investigates whether computer-assisted techniques can contribute any significant information to the characterization of astrocytic tumor aggressiveness. Two complementary computer-assisted methods were used. The first method made use of the digital image analysis of Feulgen-stained nuclei, making it possible to compute 15 morphonuclear and 8 nuclear DNA content-related (ploidy level) parameters. The second method enabled the most discriminatory parameters to be determined. This second method is the Decision Tree technique, which forms part of the Supervised Learning Algorithms. These two techniques were applied to a series of 250 supratentorial astrocytic tumors of the adult. This series included 39 low-grade (astrocytomas, AST) and 211 high-grade (47 anaplastic astrocytomas, ANA, and 164 glioblastomas, GBM) astrocytic tumors. The results show that some AST, ANA and GBM did not fit within simple logical rules. These "complex" cases were labeled NC-AST, NC-ANA and NC-GBM because they were "non-classical" (NC) with respect to their cytological features. An analysis of survival data revealed that the patients with NC-GBM had the same survival period as patients with GBM. In sharp contrast, patients with ANA survived significantly longer than patients with NC-ANA. In fact, the patients with ANA had the same survival period as patients who died from AST, while the patients with NC-ANA had a survival period similar to those with GBM. All these data show that the computer-assisted techniques used in this study can actually provide the pathologist with significant information on the characterization of astrocytic tumor aggressiveness.
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PMID:Identification of high versus lower risk clinical subgroups in a group of adult patients with supratentorial anaplastic astrocytomas. 774 36

Clinical and morphological findings in 91 patients with infantile hemangioendothelioma of the liver are reported. The study comprised 56 girls and 35 boys ranging in age from premature infant to 3 yr; one outlier patient was 18 yr old. Most patients with infantile hemangioendothelioma (87%) were first seen before the age of 6 mo. Congestive heart failure was evident in 15%. Skin hemangiomas were noted in 11%. Anemia, hyperbilirubinemia and increased AST level were present. Solitary lesions were more common than multiple ones (3:2). Immunohistochemical staining of tumor cells for factor VIII was positive in 20 of 21 cases tested; testing for blood group antigen was positive in 8 of 28 cases. Cytokeratin staining verified the presence of bile ducts, some of which appeared to be the result of transformation of injured liver. No pericytes were identified on electron microscopy. The 6-mo survival rate, based on 71 cases, was 70%. Average time of follow-up for the survivors was 7.7 yr. All deaths occurred during the initial presentation/hospitalization of infants, with the exception of two patients who died 3 mo and 7 mo after diagnosis. More recent analytic methods, including immunohistochemical stains and flow cytometric studies, do not contribute to the practical assessment of this tumor. Covariates with significant value in predicting death 6 mo after diagnosis included presence of congestive heart failure, jaundice, multiple tumor nodules and absence of cavernous differentiation.
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PMID:Infantile hemangioendothelioma of the liver. 802 Sep 3

To assess the features of multicentric occurrence in hepatocellular carcinoma, we analyzed 10 of 72 patients (14%) who had undergone hepatic resection for hepatocellular carcinoma from May 1989 to October 1992 both clinically and pathologically. The multicentric occurrence of hepatocellular carcinoma was defined among the simultaneously detected small tumors as (a) at least one tumor consisting of extremely well-differentiated (grade I) hepatocellular carcinoma growing in a replacing pattern or (b) one of a group of hepatocellular carcinomas growing in an area of adenomatous hyperplasia. Of the 10 patients, the tumors in 9 were diagnosed as synchronous multicentric hepatocellular carcinomas, whereas the tumor in 1 was considered metachronous. All patients had cirrhosis; one of them had hepatitis B virus infection and nine patients had HCV infection. The inflammatory findings in the parenchyma were determined on the basis of serum enzyme values (AST, 89 +/- 27 IU/L; ALT, 96 +/- 43 IU/L). One or two tumors in 9 of 10 patients had thin trabecular or trabecular patterns showing replacing growth. In addition, one of the two tumors in two of nine patients was observed growing in areas of adenomatous hyperplasia. Recurrences were found in 4 of 10 patients. The 3-yr disease-free survival rate was 23%. Multiple recurrences were recognized in the two patients, and in the patients who underwent repeat surgery, grade I tumors were also found. Even though these tumors were small and well-differentiated, the recurrence rate was high. Therefore to detect the recurrence of metachronous multicentric hepatocellular carcinoma at an earlier stage, careful follow-up after surgery should be carried out.
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PMID:Possible multicentric occurrence of hepatocellular carcinoma: a clinicopathological study. 813 62

Light-activated merocyanine 540 (pMC540) has been shown in our earlier studies to be effective against certain types of tumor cells and viruses, including human immunodeficiency virus (HIV-1). To test the potential extracorporeal and systemic use of pMC540, its toxicity was investigated in DBA/2 mice, pigs, and dogs. The lethal dose in DBA/2 mice after an i.p. injection was 370 mg/kg, and the 50% lethal dose (LD50) was 320 mg/kg; however, following i.v. administration, the lethal dose and the LD50 dose were 240 and 160 mg/kg, respectively. Tritium-labeled MC540 was used to study the biodistribution of pMC540 in DBA/2 mice. Almost 70% of the injected radioactivity was excreted within 6 h of injection. After 1 week, the pMC540 was almost completely cleared, with only 1.89% of the activity remaining, and had a plasma half-life of 23 h. Pigs injected with an accumulated dose of 10 mg/kg and followed for a period of 30 days did not show adverse signs of toxicity as monitored by SMAC-28 analysis, CBC profile, and blood-coagulation studies. A dog injected with a single dose of 20 mg/kg showed induction of the hepatic enzymes glutamic oxaloacetic transaminase (AST) and glutamic pyruvic transaminase (AST); however, serum levels of gamma-glutamyl transpeptidase (GGT) remained unchanged. The data presented herein may serve to identify certain drug-dose limitations in the systemic use of pMC540.
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PMID:Biodistribution and toxicity of photoproducts of merocyanine 540. 845 86

The study is a trial to test certain biochemical parameters as differential diagnostic markers between some pathological malignant cases. The first part of the present article was carried out in order to investigate the effect of both cancerous infestation and schistosomal infection on Lactate dehydrogenase (LDH), two transaminases (ALT and AST) activities and total proteins in both serum and tumor tissue isolated from bladder carcinoma patients. The activities were measured in neighboring mucosa to carcinoma tissues together with bladded tissues excised because of malignant lesions and malignant tissues excised because of urinary schistosomiasis, in Egyptian human patients. The second part was design in order to estimate the effect of cancerous disorders on the previous parameters in serum and isolated tumors among colonic carcinoma patients. In addition, the study was extended to explore the changes that might occurred in serum LDH isoenzymatic pattern among some selected cases from these patients.
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PMID:A preliminary report on the prognostic value of selected diagnostic enzymes among certain malignant and schistosomal malignant patients. 858 61

We report one case of urothelial carcinoma with diffuse intrasinusoidal metastasis to the liver and clinical presentation mimicking fulminant hepatic failure. The patient was a 69-year-old man admitted to the hospital for upper gastrointestinal hemorrhage. Two years previously he had undergone a right nephrectomy for urothelial carcinoma (T2, GII). After five days of hospital admission, he developed progressive jaundice, ascites, deteriorating mental status with high serum enzyme activities (AST, ALT, LDH, alkaline phosphatase) and death 20 days after hospitalization. No grossly detectable hepatic metastatic nodules were demonstrated. A percutaneous postmortem liver biopsy revealed a diffuse infiltration of tumor cells into the hepatic sinusoids and venous invasion.
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PMID:Acute liver failure due to diffuse intrasinusoidal metastases of urothelial carcinoma. 890 67

The oligoastrocytoma, as a mixed glioma, represents a nosologic dilemma with respect to precisely defining the oligodendroglial and astroglial phenotypes that constitute the neoplastic cell lineages of these tumors. In this study, cell image analysis with Feulgen-stained nuclei was used to distinguish between oligodendroglial and astrocytic phenotypes in oligodendrogliomas and astrocytomas and then applied to mixed oligoastrocytomas. Quantitative features with respect to chromatin pattern (30 variables) and DNA ploidy (8 variables) were evaluated on Feulgen-stained nuclei in a series of 71 gliomas using computer-assisted microscopy. These included 32 oligodendrogliomas (OLG group: 24 grade II and 8 grade III tumors according to the WHO classification), 32 astrocytomas (AST group: 13 grade II and 19 grade III tumors), and 7 oligoastrocytomas (OLGAST group). Initially, image analysis with multivariate statistical analyses (Discriminant Analysis) could identify each glial tumor group. Highly significant statistical differences were obtained distinguishing the morphonuclear features of oligodendrogliomas from those of astrocytomas, regardless of their histological grade. When compared with the 7 mixed oligoastrocytomas under study, 5 exhibited DNA ploidy and chromatin pattern characteristics similar to grade II oligodendrogliomas, I to grade III oligodendrogliomas, and I to grade II astrocytomas. Using multifactorial statistical analyses (Discriminant Analysis combined with Principal Component Analysis). It was possible to quantify the proportion of "typical" glial cell phenotypes that compose grade II and III oligodendrogliomas and grade II and III astrocytomas in each mixed glioma. Cytometric image analysis may be an important adjunct to routine histopathology for the reproducible identification of neoplasms containing a mixture of oligodendroglial and astrocytic phenotypes.
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PMID:Quantitative chromatin pattern description in Feulgen-stained nuclei as a diagnostic tool to characterize the oligodendroglial and astroglial components in mixed oligo-astrocytomas. 910 Jun 70

We previously reported that in vitro hypoxic condition enhanced VEGF level and its receptor expression in hepatic cancer cell line, HepG2. Transcatheter hepatic arterial embolization (TAE) therapy is one of the vasculo-occlusive and hypoxic challenges to hepatocellular carcinoma (HCC). Therefore, we examined the level of VEGF in sera of patients with HCC who underwent TAE during the course of the treatment. Thirty-eight patients with HCC and hepatitis C virus-positive cirrhosis were studied. Peripheral blood samples were taken before and 1, 3 and 7 days after TAE with informed consent. The serum levels of VEGF as well as hepatocyte growth factor (HGF), another hepatic remodeling factor, were measured. The molar ratio (BTR) of serum branched chain amino acid (BCAA) to tyrosine (Tyr), the serum levels of AST, ALT and LDH were also examined. Although the level of AST, ALT and LDH reached the peak value within 1 day after TAE, VEGF level increased significantly 7 days later. On the other hand, there were no significant alterations in the levels of HGF and BTR during the course of TAE. Although the level of HGF was significantly correlated with the level of VEGF before TAE, this correlation was no more observed after TAE. These data collectively suggest that VEGF may be secreted in response to clinical hypoxic intervention, TAE, independent of HGF or altered amino acid metabolism. VEGF may play a role as a sensitive marker for tumor ischemia.
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PMID:Serum vascular endothelial growth factor in the course of transcatheter arterial embolization of hepatocellular carcinoma. 1033 62


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