1/26. Corticotropin-releasing factor-like activity in ACTH producing tumors.Corticotropin-releasing factor (CRF)-like activity in two different kinds of ACTH-producing tumors (human ectopic ACTH-producing colonic cancer and rat MtT/F4 tumor) was determined by an in vitro method using isolated normal rat pituitary cells. The ACTH content of the post mortem colonic cancer was 5.5 ng/g w.wt. The ACTH content of the medium of MtT/F4 tumor cells was 153 /-32 pg/10(5) cells. The ACTH content of MtT/F4 tumor cell suspensions was elevated with increasing doses of hypothalamic median eminence extract (HME). The response of MtT/F4 tumor cells to HME was suppressed by 1 mug/ml of dexamethasone. Extracts of colonic cancer, MtT/F4 tumor and HME produced elevation of the ACTH content of the medium of isolated rat pituitary cells. The CRF-like activities of two kinds of tumor extracts in multiple dilutions ran parallel to that of HME. The CRF-like activities were 0.037 HME equiv/mg w.wt in MtT/F4 tumor and 0.052 HME equiv/mg w.wt. in colonic cancer. These results demonstrated that CRF-like activity existed in these two kinds of ACTH-producing tumors.- - - - - - - - - - ranking = 1keywords = rat (Clic here for more details about this article) |
2/26. Cancer: the eighth plague--a suggestion of pathogenesis.The current treatment of cancer is based on the assumption that this disease is the result of autonomous clonal proliferation of aberrant cells which must be excised, irradiated or selectively poisoned to achieve a cure. The presumption that the malignant cell constitutes the disease is now challenged by a variety of clinical observations and experimental studies. Like the grasshopper, which is transformed into a locust under altered environmental conditions, the cancer cell may be the manifestation of a defect in homeostatic regulation of cellular proliferation. Identification of the specific regulatory defect could allow for a more rational and more effective treatment of cancer in man.- - - - - - - - - - ranking = 0.75keywords = rat (Clic here for more details about this article) |
3/26. Granulocytosis and colony-stimulating activity (CSA) produced by a human squamous cell carcinoma.A patient with a squamous cell carcinoma accompanied by a marked granulocytosis (100,000/mm3) of unknown origin was examined for Colony-Stimulating Activity (CSA). The pleural fluid and the tumor extract revealed high CSA. The floating cells in the pleural fluid were successfully transplanted into nude mice as a localized tumor with cyst formation. The tumor invariably caused a marked granulocytosis (100,000--300,000/mm3) with induction of a conspicuous splenic granulopoiesis in the transplanted mice. High CSA were demonstrated in their cystic fluid as well. Media conditioned by the primary cultures of these tumor cells revealed the same CSA, demonstrating the direct production of CSA by the tumor itself. These results indicate the presence of human CSA producing tumor and that such a tumor may in part account for a marked granulocytosis of unknown origin observed in some patients with cancer.- - - - - - - - - - ranking = 0.5keywords = rat (Clic here for more details about this article) |
4/26. Immunodiagnosis of mesothelioma: use of antimesothelial cell serum in an indirect immunofluorescence assay.Cells isolated from human serous effusions were cultured in vitro. Monolayers of large multipolar cells were established. Antisera to the cultured cells were prepared in rabbits and rats. The antisera were absorbed with human red cells, liver powder and MOLT-4F cell line lymphocytes. Specificity of the absorbed antisera for human mesothelial cells were demonstrated in an indirect immunofluorescence assay. The antisera were used to confirm the diagnosis of mesothelioma in two cases. In both the patients, the morphologically identifiable malignant cell populations in the effusions stained positively with the antimesothelial cell serum thus establishing their mesothelial origin. Normal nonmesothelial tissue and known nonmesothelial tumors failed to react with the antisera thus confirming the specificity of the antisera.- - - - - - - - - - ranking = 0.5keywords = rat (Clic here for more details about this article) |
5/26. Metastasizing extradural ependymoma of the sacrococcygeal region: case report and review of literature.A case is discussed in which the patient presented with a primary extradural sacrococcygeal ependymoma and synchronous pulmonary metastasis. The clinical course has been characterized by recurrent pulmonary metastases. Management has consisted of repeated surgical resections of the pulmonary metastases and the tumor at the primary site; and the use of a wide spectrum of chemotherapeutic agents. transplantation of this tumor into nude mice initially resulted in rapid growth but there was spontaneous regression in the second transplants. A general discussion of the management of such lesions is presented, and the literature pertaining to this tumor is discussed.- - - - - - - - - - ranking = 1.25keywords = rat (Clic here for more details about this article) |
6/26. growth of osteoid osteoma transplanted into athymic nude mice.An osteoid osteoma, excised from the neck of the femur of a 23-year-old man, was cut into four 1.5 mm3 fragments and immediately transplanted into muscle pouches in athymic nude mice. One fragment was devitalized by lyophilization before implantation. The viable tumor cell xenografts grew, differentiated into uncalcified osteoid, and retained the characteristics of the original tumor. The killed implants were resorbed, but both the surviving viable and nonviable tumor tissue induced the connective tissue cells of the mouse host bed to proliferate and differentiate into normal cartilage and calcified bone. The mouse new bone deposits were remodeled and colonized by bone marrow, a tissue not seen in osteoid osteomas. These observations suggest that the sclerotic bone shell characteristic of osteoid osteomas may be an inductive reaction of host bed tissue to an osteoma cell product that is comparable to bone morphogenetic protein (BMP) produced by normal bone cells and transferred by normal bone matrix.- - - - - - - - - - ranking = 0.25keywords = rat (Clic here for more details about this article) |
7/26. Cell lines from human colon carcinoma with unusual cell products, double minutes, and homogeneously staining regions.Two human colon carcinoma cell lines derived from the same tumor specimen were characterized. The cell lines, COLO 320 and COLO 321, have amine precursor uptake and decarboxylation cell properties, such as ectopic production of norepinephrine, epinephrine, serotonin, adrenocorticotropic hormone, and parathyroid hormone. The cells were morphologically different from most colon cell lines. Double minutes (DM) were initially present in nearly 100% of the metaphases. In a few subcultures of COLO 320, DM have persisted for 1.5 years. However, in COLO 321 and some subcultures of COLO 320, a loss of DM was observed and new marker chromosomes with homogeneously staining regions were observed. These unusual cell lines should be valuable for studies of apudomas of the colon and the cytogenetic phenomena of DM and homogeneously staining regions.- - - - - - - - - - ranking = 0.25keywords = rat (Clic here for more details about this article) |
8/26. Morphological, biological, and biochemical characteristics of a benign human trichilemmoma cell line in vivo and in vitro.A cell line of a benign tumor, trichilemmoma, was established in vitro and has been maintained in culture for 1.5 years with more than 30 passages. Plating efficiency was less than 0.1%, and population doubling time was 10 days. Saturation density was 10(5) cells/sq cm at the time of a monolayer with 98% cell viability. Ultrastructurally, tissue-cultured trichilemmoma cells showed desmosome-tonofilament complexes at cell-to-cell junctions. The tissue-cultured cells synthesized abundant glycogen (50 to 100 microgram/10(6) cells) e was 10 days. Saturation density was 10(5) cells/sq cm at the time of a monolayer with 98% cell viability. Ultrastructurally, tissue-cultured trichilemmoma cells showed desmosome-tonofilament complexes at cell-to-cell junctions. The tissue-cultured cells synthesized abundant glycogen (50 to 100 microgram/10(6) cells) e was 10 days. Saturation density was 10(5) cells/sq cm at the time of a monolayer with 98% cell viability. Ultrastructurally, tissue-cultured trichilemmoma cells showed desmosome-tonofilament complexes at cell-to-cell junctions. The tissue-cultured cells synthesized abundant glycogen (50 to 100 microgram/10(6) cells) as observed in vivo. Gas chromatographic analysis revealed that extracted glycogen was composed of glucose alone. Chromosome analyses with trypsin-Giemsa banding showed an abnormal karyotype with hypodiploid modal numbers of 44 and 45. There were four marker chromosomes observed in 100% of cells in 100 metaphase cells examined. Cells did not grow on fibroblast monolayers or in soft agar in vitro but did induce tumors in athymic nude mice (12 of 15) after the s.c. injection of tissue-cultured cells (2.5 x 10(6) to 4.5 x 10(7) cells/mouse). The histological characteristics of the tumors in nude mice were similar to those of the original tumor. This is the first time, to our knowledge, that a benign human tumor cell line has been established in vitro which can induce tumors in nude mice.- - - - - - - - - - ranking = 0.75keywords = rat (Clic here for more details about this article) |
9/26. Transcatheter microembolization with ferropolysaccharide. A new approach to ferromagnetic embolization of tumors: preliminary report.A new embolic material has been devised to improve the therapeutic effect of ferromagnetic embolization upon tumors. iron sponge microspheres (diameter 10-30 mu) were suspended in viscous, aqueous polysaccharide solution, dextran 40, and sodium carboxymethyl cellulose (Ferro-polysaccharide, FPS). Transcatheter embolization with FPS was performed under external magnetic control (2,800 gauss) in dog kidneys and VX2 carcinomas of rabbits, causing widespread, intraparenchymal vascular occlusion of target vessels. Neither recanalization nor collateral circulation was found to the infarcted areas, and the embolized tumors had extensive necrosis with resultant tumor regression. No significant untoward reaction or other undesirable embolization was noted serologically or histologically, even after intravenous administration of FPS. Clinical application to two patients, one with a hepatoma and the other with a renal cell carcinoma, resulted in excellent tumor infarction with no significant side effects.- - - - - - - - - - ranking = 0.25keywords = rat (Clic here for more details about this article) |
10/26. Attempt at local administration of anticancer agents in the form of fat emulsion.A fat emulsion when injected into tissue is scarcely taken up by the blood vascular system but is retained within the tissue over a relatively extended period, and is distributed slowly into the surrounding tissues and to the regional lymph nodes. Attempts were made to use this property of the emulsion in the local administration of anticancer agents in emulsion, both in experimental animals and in man. The concentrations of bleomycin in the tumor tissue of rats were significantly higher after the intratumoral injection of the emulsion form than when the drug was administered in the aqueous solution, either systemically or intratumorally. Experimental antitumor activity against this tumor was superior after the bleomycin emulsion, as well. In the clinical trials six of eight patients with either squamous cell carcinoma of skin or local recurrence of adenocarcinoma of the breast responded favorably to this treatment.- - - - - - - - - - ranking = 2.25keywords = rat (Clic here for more details about this article) |
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