Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006826 (cancer)
 1,092,456 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Male F344 rats, 8 weeks of age, were given 16 intrarectal administrations of N-methyl-N-nitrosourea (NMU) at one of three dose levels over a period of 8 weeks. Five days after the final NMU instillation, rats were placed on one of three diets: chow with gelatin beadlets, chow with beadlets containing 0.024% 13-cis-retinoic acid, or chow and beadlets with 0.006% of the trimethylmethoxy phenyl analog of retinoic acid ethylamide. Groups of 20-40 rats were killed at 22-26 weeks after the first carcinogen treatment. The number of rats with colon carcinoma and the number of tumors per rat were dose related. In addition, "blind" histopathologic evaluation of four predesignate colon locations revealed a dose-related incidence of microscopic preinvasive and invasive colon carcinomas. The feeding of diets containing these two retinoids did not significantly alter the incidence of these parameters of carcinogenesis or the mean histopathologic score at predesignated colon locations for preinvasive or invasive neoplastic lesions. Over 90% of the colon neoplasms induced were invasive tubulopapillary adenocarcinomas. The diameters of the tumors correlated significantly with degrees of invasion of the colons. Only 1 tumor (a signet ring carcinoma) metastasized to the peritoneal cavity. Only 2 of 300 rats treated with NMU had tumors at sites other than the colon.
J Natl Cancer Inst 1978 Jun
PMID:Dose response to intrarectal administration of N-methyl-N-nitrosourea and histopathologic evaluation of the effect of two retinoids on colon lesions induced in rats. 65 Jul 11

The DNA alkaline elution technique provides a sensitive assay for the effects of DNA-damaging drugs in mammalian cells. We have adapted this method to permit measurements of effects on DNA in solid tumors. Human colon carcinoma xenografts in nude mice were treated with a single i.p. injection of 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea, and the effects on the DNA were followed for 19 hr. Drug doses in the pharmacological range produced significant reductions in DNA alkaline elution rates in assays in which X-ray was used to introduce a standard frequency of single-strand breaks. These changes in alkaline elution rate were attribute to the production of both DNA interstrand and DNA-protein cross-links, which were distinguished from each other on the basis of the extent to which the effect on elution could be reversed by proteinase K. Crosslinking increased for about 8 hr after treatment with little change thereafter up to 19 hr. A drug-resistant tumor line exhibited substantially less cross-linking than did a drug-sensitive line at all time points examined.
Cancer Res 1978 Aug
PMID:DNA cross-linking by in vivo treatment with 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea of sensitive and resistant human colon carcinoma xenograms in nude mice. 66 42

Recent developments in the field of polyps of the colon are discussed. The WHO classification represents a definite improvement. Apart from standardization, non-neoplastic polypoid changes of varying etiology and hamartomatous polyps are clearly distinguished from neoplastic, non-malignant adenomas. The various changes are outlined briefly in their essential characteristics. Clear-cut differentiation from early invasive cancer is of considerable importance for practical therapeutic purposes. Focal carcinoma within an adenoma is referred to only if invasion through the muscularis mucosae is established, while all other changes confined to the mucosa are termed adenomas with focal epithelial atypia. With regard to the relation between adenoma and cancer of the colon, recent results on topographical distribution of adenomas through the colon are of considerable significance. From serial studies of biopsy and autopsy specimens on the one hand, and from assessment of colon carcinoma incidence compared with mortality rates in carcinomas of different localizations on the other, it is evident that special attention should be given henceforward to adenomas, possible precursors, and carcinomas in the upper segments of the colon.
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PMID:[Pathology of colonic polyps]. 67 94

The growth characteristics and metastatic behavior of human tumors growing in athymic nude mice were studied. Human tumor cell lines HEp-2 (carcinoma or larynx) and SW480 (colon carcinoma) were transplanted into athymic nude mice of BALB/c origin. Tumor cells (1 x 10(6) and 2 x 10(7)) were given either s.c. or i.p. Following s.c. injection tumors developed rapidly to become easily palpable with 2 weeks forming a s.c. tumor focus surrounded by a thick fibrous capsule. Animals with s.c. transplants were little affected by the growing tumor. At the time they were sacrificed at Day 34 (HEp-2) and 62 (SW480), a large part of the tumor was necrotic. Capsular infiltration and invasion of lymphatic vessels and perineural and perivascular lymphatic spaces were observed. Metastases to regional lymph nodes were seen in animals kept alive for up to 6 months. Following i.p. transplantation, tumors spread widely in the peritoneal cavity, invaded intraabdominal organs, and metastasized to mediastinal lymph nodes and lungs. Fifteen of 26 animals (60%) developed metastases. Necrosis of the i.p. growing tumors was minimal. All animals in this group died as a result of tumor growth.
Cancer Res 1978 Oct
PMID:Growth patterns and metastatic behavior of human tumors growing in athymic mice. 68 9

Several biochemical effects of 5-fluorouracil (5-FU) including inhibition of the incorporation of 3H-deoxyuridine (3H-UdR) into DNA, inhibition of ribosome formation, and formation of 5-fluoro-2'-deoxyuridine-5'-monophosphate (FdUMP) were examined in samples of human colon carcinomas to determine if any of these drug effects might have predictive value as a reliable guide to 5-FU therapy. For comparison, the solid rat Walker 256 carcinosarcoma, which is only minimally responsive to 5-FU, was also studied. For each of the biochemical effects of 5-FU measured in the various samples of Walker 256 tumors, the responses were consistent and varied within a narrow range. In contrast, the formation of FdUMP from 5-FU and the degree of inhibition of the incorporation of 3H-UdR into DNA by 5-FU were extremely variable in the population of human colon carcinomas examined. In all human tumors examined, 5-FU caused a reduction in the formation of ribosomes, but even in the absence of 5-FU, the total amount of ribosome synthesis was so low that it makes measurement difficult to quantitate. Based on our data, a study might be warranted to determine if there is a correlation between FdUMP formation and responsiveness of colon carcinoma to 5-FU therapy.
Cancer Treat Rep 1978 Jul
PMID:Effects of 5-fluorouracil on human colon carcinoma and solid rat Walker 256 carcinosarcoma: evaluation as in vitro predictors of clinical response. 68 47

Prior studies confirm the increased incidence of carcinoma of the colon in chronic ulcerative colitis. The authors reviewed clinical and histologic data retrospectively in 23 patients with colon carcinoma and chronic ulcerative colitis. Twenty-two of these patients had dysplasia of colonic epithelium remote from the cancer. The authors prospectively reviewed clinical data and rectal and colonoscopic biopsy specimens on 36 patients with chronic ulcerative colitis, 12 with Crohn's colitis, and 12 with miscellaneous disorders. Eight patients with chronic ulcerative colitis had dysplasia; 6 have had colectomy, and 2 of these had carcinoma. No patient without chronic ulcerative colitis had dysplasia. Patients with chronic ulcerative colitis should have periodic rectal and colonoscopic biopsies, and those with moderate to marked dysplasia require colectomy because of the increased risk of colon carcinoma.
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PMID:Malignant potential of chronic ulcerative colitis. Preliminary report. 75 30

With the paired-labeled antibody technique, the in vivo localization of radioiodinate, affinity-purified antibody to carcinoembryonic antigen (CEA) was studied in GW-39, a xenografted, CEA-producing tumor model. When compared to the whole immunoglobulin G fraction, a 4-fold greater tumor accumulation of radioantibody was obtained with affinity-purified specific CEA antibody. The degree of increased tumor localization of affinity-purified antibody was similar to its improved immunoreactivity as observed in radioimmunoassay and binding to CEA immunoadsorbent. Affinity-purified antibody cross-reactive with CEA and colon carcinoma antigen III was as equally effective in tumor localization as was specific CEA antibody prepared similarly. It thus appears that affinity-purified CEA radioantibody will provide a superior tumor-imaging agent for clinical use.
Cancer Res 1977 May
PMID:Localization of GW-39 human tumors in hamsters by affinity-purified antibody to carcinoembryonic antigen. 85 62

Antibody-dependent lymphocyte cytotoxicity against human colon carcinoma cells grown in vitro was demonstrated with rabbit anti-carcinoembryonic antigen (CEA) antisera and normal human lymphocytes. The same antisera produced no tumor cell lysis in a complement-dependent cytotoxicity test. The specificity of the reaction was demonstrated by the inhibition of antibody-dependent lymphocyte cytotoxicity after the addition of increasing amounts of purified CEA to the antiserum and by the fact that only tumor cell lines expressing CEA on their surface were lysed. Antibody-dependent lymphocyte cytotoxicity was also observed against two colon carcinoma cell lines that expressed Blood Group A antigen, using a human serum containing anti-Blood Group A antibodies of the immunoglobulin G class. This reaction was specifically inhibited by absorption with Blood Group A red cells, whereas the anti-CEA-dependent cytotoxicity was not inhibited by absorption with red cells of different blood groups.
Cancer Res 1977 Aug
PMID:Antibody-dependent cell-mediated cytolysis of human colon carcinoma cells induced by specific antisera against carcinoembryonic antigen. 87 92

Antibody dependent lymphocyte (K cell) mediated lysis of tumor cells in vitro was used to assay for cell surface associated carcinoembryonic antigen (CEA) and two CEA-related normal tissue components, "normal glycoprotein" (NGP) and biliary glycoprotein I (BGP I). Three tumor cell lines were used as target cells. These were HT-29, colon carcinoma, T-24, urinary bladder transitional cell carcinoma and Mel-1, malignant melanoma. To induce lysis we used the IgG-fraction of specific rabbit and monkey anti-CEA sera and of specific rabbit anti-NGP and anti-BGP I sera, respectively. Purified human lymphocytes were used as effector cells. HT-29 was efficiently killed by low concentrations of rabbit anti-CEA and less efficiently by monkey anti-CEA. T-24 and Mel-1 were not lysed by anti-CEA, HT-29 and T-24 were lysed by low concentrations of anti-BGP I. In contrast only HT-29 was lysed by anti-NGP. Only a fraction of the tumor cells was killed by the different antisera although kinetic studies showed that the lytic reaction was complete well before the end of the eighteen hour incubation period used in the assay. Anti-CEA and anti-BGP I gave 30-40% corrected lysis of HT-29. With anti-NGP the corresponding figure was 10-20%.
Int J Cancer 1977 Jun 15
PMID:K cell mediated lysis of cultured colon carcinoma and urinary bladder carcinoma cells induced by monospecific antisera against carcinoembryonic antigen (CEA) and two CEA-related normal glycoproteins. 87 41

Scintigraphic criteria for hepatic metastases were studied by examination of 333 liver scintigrams performed on 275 patients with primary cancers of the colon or breast. Focal defects in radiocolloid distribution correctly signaled the presence of metastatic colon carcinoma in 88% of the patients with that disease and incorrectly pointed to only 6% of the patients without such metastases. In contrast, the same criterion detected only 67% of hepatic metastases from breast carcinoma. This lower sensitivity could be improved to 87% by adding heterogeneity or hepatomegaly to the criteria for abnormality when patients with breast cancer are examined. Scintigraphic indicators of metastatic disease may vary according to the site of primary cancer.
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PMID:Scintigraphic criteria for hepatic metastases from cancer of the colon and breast. 93 8


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