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

Altered carbohydrate metabolism associated with fibrosarcomas and chondrosarcomas has been well-documented in past literature. This report describes abnormal carbohydrate metabolism in 2 osteosarcoma patients, and abnormalities in growth hormone and somatomedin serum levels. Experimental evidence is presented showing in vitro suppression of osteosarcoma tumor cell proliferation by 17 beta Estradiol. Estrogen inhibition of linear bone growth, cartilage proliferation, and somatomedin is discussed with reference to possible estrogen therapy in osteosarcoma.
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PMID:Investigation of carbohydrate metabolism and somatomedin in osteosarcoma patients. 105 23

Recent evidence suggests that endocrine factors play an important role in the natural history of osteosarcoma. The occurrence of this tumor in the metaphysis of rapidly growing adolescents, coupled with increased female survival led to the investigation of the effects of various hormones on cultured osteosarcoma cells. The in vitro effects of physiologic concentrations of human growth hormone, 17beta estradiol, and progesterone on cultured osteosarcoma cells and chondrocytes are presented. Growth hormone significantly enhances 3H-thymidine incorporation in osteosarcoma cells and chondrocytes, in the presence of human serum. The use of other sera, culture media, or heat inactivation of the human serum abolishes this effect. Estradiol and progesterone, alone, or in combination produce significant suppression of DNA synthesis in cultured tumor cells. Several sera contain a heat-labile factor which has the capacity to block the suppressive effect of estradiol. This factor could be overcome by increasing the concentration of hormone, or by heat-inactivation of the serum. The use of hormone therapy in the treatment of osteosarcoma has never been reported, despite its demonstrated value in certain other malignancies. In light of these observations and considering the poor prognosis in this disease it seems reasonable to initiate a study of adjunctive hormone therapy in osteosarcama.
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PMID:Hormone suppression of DNA synthesis in cultured chondrocyte and osteosarcoma cell line. 105 8

A 53-year-old normotensive, normokalemic female presented with a 6-month history of virilization. Estradiol, LH, FSH, urinary-free cortisol, and DHEA-S levels were normal. Pelvic ultrasound and computerized tomography were also within normal limits. Her serum testosterone (551 ng/dl; nl, 20-70) and plasma prorenin (124 ng AI/ml/hr; nl, less than 50) levels were elevated. At surgery, a lipoid/steroid cell tumor of the right ovary was removed. Postoperative testosterone and prorenin levels were normal. Ovarian tumor cells, in culture, produced large amounts of prorenin. Immunohistochemistry localized prorenin and/or renin to tumor cells. Determining plasma prorenin levels may be a useful adjunct in diagnosing or following patients with nonepithelial ovarian tumors. A larger clinical study of prorenin levels in patients with such tumors is needed.
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PMID:Secretion of prorenin by a virilizing ovarian tumor. 131 55

Recent studies using both normal and tumoral pituitary cell cultures have demonstrated that growth hormone (GH) and prolactin (PRL) secreting populations contain cells which release either one or both of these hormones. In order to determine whether these two cell types can be differentially regulated by hypothalamic factors we performed the following study employing plaque assays for GH and PRL. Using cultures of GH3 cells, a rat tumor cell line which contains both of these cell types, we found that the hypothalamic factors vasoactive intestinal peptide (VIP) and thyrotropin releasing hormone (TRH) when used together had a greater influence on plaque formation than when each was used individually. This suggested that cells were present in culture that responded to one peptide but not the other. Estradiol-treated cultures (which contain only dual-secreting cells) were then evaluated for VIP and TRH responsiveness and found to respond to TRH but not VIP. Finally, we assessed the peptide sensitivity of cultures that were exposed to a conjugate of VIP and the A-chain of ricin (a potent cytotoxin). In addition to eliminating VIP-responsive cells, this treatment markedly reduced the proportions of cells secreting GH-only while having no appreciable influence on dual-hormone secretors. When taken together, our findings indicate that single and dual secretors respond differently to at least two hypothalamic secretagogues and suggest that regulatory differences between these cell types may be important in the control of GH and PRL secretion.
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PMID:Single and dual hormone secretors in GH3 cultures respond differently to hypothalamic factors. 144 81

An animal model for studying tumor dormancy was established by two-way selection of tumor-progressive and nonprogressive (tumor-dormant state) ddY mice in the same basal stock. In the tumor-progressive (prg) substrain of mice, Ehrlich ascites tumor cells (2 x 10(7)) subcutaneously inoculated into the dorsal skin formed a progressive solid tumor. In the tumor-dormant substrain (drm) of mice, the same tumor cells did not grow at all but formed a small caked nodule (1 to 3 mm in diameter) within 1 week. Some of the tumor cells persisted in the nodule at least 3 months without apparent mitotic figures. Such dormant tumor cells emerged and revealed outgrowth to overt solid tumors after they were transplanted into the dorsal skin of prg mice or into athymic mice (C57BL/6J nu/nu). To estimate the predisposition of drm mice to form tumors, the effect of certain drugs on the tumor-dormant state was examined. Estradiol, progesterone, dexamethasone, prostaglandin E2, Cyclosporin A, and collagenase all failed to promote the emergence of dormant tumor cells in drm mice.
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PMID:Tumor dormancy and the effect of selected drugs on the tumor-dormant state. 147 6

The effects of hormonal ablation, estrogen, estrogen-derived cytotoxic agent, and estrogen antagonist therapies used clinically were evaluated on in vitro colony formation, in vivo growth, and lymphatic and pulmonary metastasis of the PAIII tumor. Ventral prostatic and seminal vesicle weights were evaluated in the same animals to assess androgen-related responses. Estradiol, estramustine phosphate, and testosterone had no effects on PAIII colony formation in vitro. Castration, hypophysectomy, estradiol benzoate, and estramustine phosphate treatment of PAIII-bearing Lobund Wistar rats produced significant (P less than 0.05) regression of male accessory sex organs. Of these treatments, only hypophysectomy had significant (P less than 0.05) inhibitory effects on primary PAIII growth and lymphatic and pulmonary metastasis. LY117018 [6-hydroxy-2-(p-hydroxyphenyl)benzo(b)thien-3-yl-p-2-(l-pyrrolidin yl)ethoxy phenyl ketone] has antiestrogenic activity but produces no significant agonist responses. LY117018 had no effect upon PAIII colony formation in vitro. Following s.c. implantation of PAIII cells, LY117018 (2.0, 10.0, or 20.0 mg/kg s.c.) had no effect on primary tumor growth in the tail. In vitro LY117018 administration produced marked antimetastatic effects. In a dose-dependent manner, LY117018 inhibited PAIII metastasis to the gluteal (97%) and iliac lymph nodes (88%) (P less than 0.05 for both). LY117018 also maximally inhibited pulmonary metastasis by 86% (P less than 0.05). Maximal regression of 42% for ventral prostatic and 35% for seminal vesicle weights were also seen after LY117018 administration (P less than 0.05 for both). Co-administration of estradiol benzoate had no antagonistic effect upon the antitumor responses produced by LY117018. The mechanism of action of LY117018 is not known. The failure of estradiol benzoate to affect PAIII growth and metastasis supports the contention that the responses to LY117018 are not attributable to simple antagonism of estrogen action. LY117018 may be exerting its antitumor effects through autocrine, paracrine, or endocrine mechanisms. LY117018 represents a class of agents with potential utility in treating metastatic cancer of the prostate.
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PMID:Comparative antitumor effects of hormonal ablation, estrogen agonist, estrogen cytotoxic derivative, and antiestrogen in the PAIII rat prostatic adenocarcinoma. 151 32

Estradiol 17 beta-hydroxysteroid dehydrogenase (E2DH) is the enzyme responsible for the interconversion of estrone (E1), and the more biologically potent steroid, estradiol (E2), and has a crucial role in regulating breast tissue concentrations of E2. It has previously been shown that breast tumor cytosol is able to preferentially stimulate the reductive conversion of E1 to E2 in cultured MCF-7 breast cancer cells. In this study the stimulatory factor(s) from breast tumor cytosol have been partially purified by gel filtration and affinity chromatography. Human serum albumin (HSA) has been identified as a component of this bioactive fraction. Subsequent testing of commercially purified HSA preparations has revealed the ability of some preparations to be highly stimulatory. The albumin present in breast tumor cytosol may therefore be a contributing factor to the observed stimulation of reductive E2DH activity in cultured MCF-7 cells. Such a mechanism may account in part for the higher concentrations of E2 which are observed in breast tumors in vivo.
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PMID:Identification of albumin in breast tumor cytosol as a factor involved in the stimulation of estradiol 17 beta-hydroxysteroid dehydrogenase (reductive) activity. 155 73

Estradiol, progesterone, 17-hydroxyprogesterone, androstenedione and CA125 were assayed in 25 women (12 oophorectomized before entering the study) with ovarian carcinoma. The data from patients were ordered according to the presence or absence of the gonads. The patients with ovaries (Group A) showed significantly higher levels of estradiol (p less than 0.01), progesterone (p less than 0.01) and 17-hydroxyprogesterone (p less than 0.01) than controls. This difference was not observed between oophorectomized patients (Group B) and controls. CA125 levels were significantly higher in patients that in controls (p less than 0.001) irrespective of the ovarian status of the patients. Eleven patients were followed during chemotherapy. Significant reductions of estradiol (p less than 0.01) and CA125 (p less than 0.001) levels after three courses of chemotherapy were observed. These data confirm that women with ovarian carcinoma produce an abnormal amount of steroids. Nevertheless, a marked difference between patients with and without ovaries was observed, suggesting that reported data might be biased by the presence of gonadal tissue. Thus the clinical application of steroids as tumor markers in unselected patients is limited.
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PMID:Estradiol, progesterone, 17-hydroxyprogesterone, androstenedione and CA125 in patients with ovarian carcinoma. 158 Jan 64

In March 1989, ultrasonography revealed a hepatic mass in a 40 year old nulliparous woman who was then referred to the University of Southern California--Los Angeles (UCLA) Liver Unit. She exhibited no symptoms of a liver condition. From 19-28 years old, she took the combined oral contraceptive (OC) Ovulen 21 for irregular menses. After a brief period of taking Ortho Novum 1/80, she took Demulen 1/35-24 between ages 28-34. Her physician diagnoses endometriosis at 34. He stopped OC therapy and prescribed the progestin Norlutate. She had no history of hepatitis, toxin exposure, and previous liver disease. Further no one in her family had had liver disease or neoplasms. Computer tomography identified a 6.5 cm x 3.5 cm mass in the right lobe of the liver which matched a cold defect on a liver scan using technetium Tc 99m sulfur colloid. The mass selectively took up gallium. Arteriography revealed the mass to be a vascular tumor, but it did not exhibit a typical vascular pattern of an adenoma or the neovascularity of hepatocellular carcinoma. Physicians at UCLA used peritoneoscopy to take percutaneous needle biopsies of the right lobe which confirmed a hepatic adenoma. they then removed the right lobe of the liver. The remaining part of the liver was normal. Histologic examinations of the removed section showed features of a well differentiated hepatocellular carcinoma. Further tumor cells had invaded normal hepatic parenchyma. The physicians believed that hepatic adenoma was in the process of transforming into hepatocellular carcinoma in this patient. They thought that long term OC use, and possibly long term progestin use, may have contributed to the formation of the liver neoplasms. They emphasized the need for a pilot study to develop guidelines on surveillance ultrasonography of women taking OCs over a long period.
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PMID:Hepatocellular carcinoma coexisting with hepatic adenoma. Incidental discovery after long-term oral contraceptive use. 166 98

17 alpha-Ethinylestradiol (EE2)-mediated promotion of diethylnitrosamine (DEN)-initiated liver tumors was evaluated in distinct hepatocyte subpopulations. Our initiation-promotion regime consisted of a single dose of DEN (200 mg/kg) to ovariectomized rats, followed by chronic exposure to EE2 (90 micrograms/kg/day for 30 weeks). We observed significant increases in liver and uterine organ wts which were associated with liver tumor formation. Isolated hepatocytes were separated by elutriation into seven subpopulations. The early eluting subpopulations consisted of a greater proportion of diploid cells and they exhibited a preferential uptake of acridine orange, which is characteristic of periportal cells. With the increasing order of elutriated fractions, hepatocyte subpopulations of tetraploid and octaploid cells were obtained. Elutriation revealed that EE2 promotion enhanced nuclear estrogen receptor levels (3-fold) and gamma-glutamyltranspeptidase activity (5-fold) to a greater extent in the early eluting diploid subpopulations (1 and 2), even though total estrogen receptor (ER) levels were higher in the later eluting subpopulations. The stimulatory effect of EE2 on ER levels was associated with an increased ER occupancy in all subpopulations, although the effect was greatest in the later eluting fractions. Chronic EE2 exposure induced the emergence of new hepatocyte populations within fractions 6 and 7. Enhanced cell growth was observed in the DEN/EE2-derived hepatocytes by flow cytometric measurements of DNA synthesis. The new populations of altered cells expressed high levels of epidermal growth factor receptor (EGFR), with 90% of the cells positive for EGFR-antibody. In summary, our data demonstrate that many effects of EE2 on hepatocyte pathways involved in growth control occur in nearly all populations of cells, derived by elutriation although some effects such as the emergence of an EGFR-enriched population of hepatocytes are localized in specific populations.
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PMID:Estrogen receptor, epidermal growth factor receptor and cellular ploidy in elutriated subpopulations of hepatocytes during liver tumor promotion by 17 alpha-ethinylestradiol in rats. 167 26


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