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

The histologic, morphometric, immunohistochemical, and ultrastructural study of a malignant Brenner tumor in a postmenopausal women presenting with vaginal bleeding is described. A comparison with transitional cell carcinomas is made, and the use of morphometry in grading the urothelial-like epithelium in malignant Brenner tumors is suggested. High preoperative urinary estrogen, low serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels and histologically confirmed atypical endometrial hyperplasia suggested a hyperestrogenism. The reduction in urinary estrogen and the increase in serum LH and FSH after tumor removal and the presence of aromatase activity detected in tumor microsomes confirmed that the tumor was synthesizing estrogen. Estrogen receptors were undetectable both by biochemical and histochemical analysis in the tumor.
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PMID:Malignant Brenner tumor. A histologic, morphometrical, immunohistochemical, and ultrastructural study. 242 24

In an attempt to induce a high incidence of prostate carcinoma, N-methylnitrosourea (MNU), a multipotential carcinogen, was given during the period of cell proliferation of the prostate gland induced by administration of methyltestosterone (MT) to F344 rats pretreated with ethinyl estradiol (EE). Rats were given diet containing EE for 3 weeks and then diet containing 300 ppm of MT for 5 days. On the 3rd day of MT-treatment, they were given a single intravenous injection of 50 mg/kg body wt. of MNU. Control rats (group 4) were given vehicle only. After treatment with MT for 5 days, the rats were given basal diet (group 1), diet containing MT (group 2) or diet periodically containing EE (groups 3 and 4) until the end of the experiment (week 60). Carcinoma of the prostate was found only in 1 of 17 rats in group 3. Atypical hyperplasia of the prostate was found in 1 of 10 rats in group 1 and 3 of 17 rats in group 2. The incidences of atypical hyperplasia of the seminal vesicles in groups 1-3 were 0%, 41% and 29%, respectively. No tumor promoting effect of MT or EE was observed except promotion by MT on the development of atypical hyperplasia of the seminal vesicles.
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PMID:Lesions of the prostate glands and seminal vesicles induced by N-methylnitrosourea in F344 rats pretreated with ethinyl estradiol. 243 49

Tissue culture techniques have been developed for studying the influence of hormones on human breast tissues. The present study demonstrated that estrogen induced a highly significant increase in 3H-thymidine incorporation into DNA and labelling index of ductal epithelium of fibrocystic disease; there was no effect of progesterone, either alone or in combination with ovine prolactin, on benign lesions. Estrogen stimulated certain malignant tumors derived from postmenopausal women. These studies also showed that there was an inhibitory effect of 3H-thymidine incorporation into DNA by the effect of progesterone on malignant lesions. When menopausal status was considered, it was found that DNA synthesis was significantly higher in the presence of insulin and hydrocortisone in malignant tumors derived from premenopausal women than from postmenopausal women, or than in benign lesions. Thus, the present findings may provide evidence that specific activity may be an important measurement for breast tumor DNA synthesis in response to ovarian hormones or other substances.
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PMID:Influence of hormones on DNA synthesis of breast tumors in culture. 243 57

Clinical and laboratory evidence of an association of oral contraceptive (OC) use with the subsequent development of benign and malignant hepatobiliary neoplasia is growing. The authors present a case in which an adenoma within a large, multicentric anaplastic spindle cell carcinoma occurred in a woman with a long history of OC use. The patient, a 38-year-old gravida 2, para 2, was diagnosed following low-grade fevers and right upper quadrant pain. A partial hepatectomy was performed with no complications; however, a follow-up examination 2 months later revealed widespread intra-abdominal tumor recurrence histologically identical to the original tumor. Immunostaining for alpha 1 antitrypsin and keratin was strongly positive in tumor cells, indicating a biliary derivation. Electron microscopy indicated an epithelial derivation as well, including the presence of intracellular lumens, intermediary filaments, and numerous intercellular junctions. Estrogen and progesterone receptors were negative in the tumor. The tritiated thymidine labeling index was 5.05%, with an estimated potential doubling time of 11 days. This woman had no history of hepatitis, no family or personal history of neoplasms, and no known hepatotoxin exposure. The only medication used by the patient was Norlestrin, an OC containing 1 mg norethindrone and 50 mcg ethinyl estradiol that she had taken continuously for the past 8 years.
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PMID:Hepatic adenoma within a spindle cell carcinoma in a woman with a long history of oral contraceptives. 243 48

No significant testing in screening or early diagnosis of cancer is possible at present. Tumor markers of different origin are useful in the search for occult locoregional recurrence, metastatic disease, or early detection of progression irrespective of localization. The comparative analysis of tumor markers for follow-up is mandatory. Estrogen- and progesterone-receptor assays for prognostic evaluation in endometrial and breast carcinoma, and in some cases of ovarian tumors, should complete any pretherapeutic step. There is a possible link with epidermal-growth factor (EGF) with regard to uncontrolled growth of tumors in hormone-dependent (target) organs.
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PMID:Antigenic markers of genital carcinoma. 245 60

Two cDNA libraries have been constructed with RNA prepared from the estrogen-responsive breast cancer cell lines, MCF7 and ZR 75. They were screened by differential hybridization for estrogen-regulated sequences. A total of 11 different RNAs were isolated from the MCF7 cell cDNA library and four from the ZR 75 cell cDNA library. Only two sequences were isolated from both libraries. The levels of the 13 different RNAs are induced between 2.5- and 100-fold by estrogen in MCF7 cells. The expression and regulation by estrogen of the RNAs was examined in eight different human tumor cell lines. The relative abundance of each RNA varied in the different cell lines. The expression of three RNAs (pNR-1, pNR-2, and pNR-25) was detected only in estrogen-responsive breast cancer cells. The sequences that were expressed in all eight cell lines were regulated by estrogen only in the three estrogen-responsive breast cancer cell lines. The response of the RNAs to other classes of steroids and to different concentrations of estrogen was characterized in more detail. The extent to which different concentrations of estradiol induced each RNA varied, but half-maximal induction of most of the RNAs occurred between 2 and 5 X 10(-11) M. The time at which increased RNA levels were first detected following exposure to estradiol also varied. Estrogen increased the levels of some RNAs within 15 min, while for others there was a lag of 4 h.
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PMID:Identification and characterization of estrogen-regulated RNAs in human breast cancer cells. 245 37

The steroid hormone receptor content of 32 malignant ovarian tumors was compared with the in vitro effectiveness of 4 hydroxytamoxifen (OH-TAM) and medroxy-progesterone acetate (MPA) tested in the Human Tumor Colony Forming Assay (HTCFA). The sensitivity for the receptor determination was 5 fmol/mg cytosol protein. Estrogen receptors (ER) and progesterone receptors (PR) were found in 15 (47%) and 13 (41%) of the tumors respectively. As standard criteria for the HTCFA, a minimum of 30 colonies with a diameter of more than 60 microns and 100 microns was used in the control group. The in-vitro sensitivity of ovarian tumors to OH-TAM and MPA was independent on the ER or PR content, and amounted to 9% for OH-TAM and 6% for MPA. However, all 12 ER-PR-tumors proved resistant to OH-TAM and MPA. 18 ovarian tumors showed a sufficient colony growth, even in the size class exceeding 100 microns. With a minimum colony size of 60 microns and 100 microns, 17% and 33% respectively were sensitive to OH-TAM. A similar effect on the proliferative capacity of the Tumor Colony Forming Units (TCFUs), unrelated to PR, was observed with MPA. Dependent on colony size, we found an increasing sensitivity against MPA from 11% to 22%. The in-vitro effectiveness of both OH-TAM and MPA in the clonogenic assay of malignant ovarian tumors was certainly not as potent as suggested by the results obtained in biochemical steroid hormone receptor analysis. To prove the hormonal response in the HTCFA, it is necessary to determine number and size of the colonies as an expression of their proliferative potential.
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PMID:[Hormone dependence of malignant ovarian tumors--an in vitro model]. 254 77

Consecutive serial cryostat-frozen sections of 157 human mammary carcinomas and the uteri of six immature New Zealand white rabbits were stained histochemically for cytoplasmic estrogen receptor (ER) and nuclear ER by a fluorescent estrogen compound (Fluorocep Estrogen, Zeus Technologies, Inc., Raritan, NJ) and by a monoclonal antibody immunoperoxidase technique (ER-ICA, Abbott Laboratories, North Chicago, IL), respectively. The percentage of the ER-positive cells in the cancer cell population under observation was estimated and recorded. The results of the cytoplasmic ER assay were compared with those of the nuclear ER assay in each tumor; all cancers with less than 10% ER-positive cancer cells were grouped together as ER-negative tumors, the cancers with 30% or more ER-positive cancer cells as ER-positive tumors, and those with 10% to 29% ER-positive cancer cells as borderline positive. According to this manner of classification, 94% to 97% of the ER-positive mammary carcinomas diagnosed by one histochemical assay would have been identified as such by the other with no more than 10% difference in the ER-positive cell counts. The majority of ER-positive breast cancer cells and practically all of the luminal lining cells of the immature rabbit endometrium had coexistent cytoplasmic and nuclear ER. In the mammary cancers containing less than 30% ER-positive cancer cells, there was a greater (up to 20%) discrepancy in positive cell counts between the cytoplasmic ER assay and the nuclear ER assay. This discrepancy may be due to sampling errors of small clones of ER-positive cancer cells in two adjacent sections, difference in antigenic determinants between the cytoplasmic and the nuclear ER, and the binding sites in the nuclear ER being preoccupied by estrogen. The findings of this study appear to support the hypothesis that there are ER in the cytoplasm and the nucleus of the mammary carcinoma cells and the epithelial cells of the endometrium.
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PMID:Coexistence of cytoplasmic and nuclear estrogen receptors. A histochemical study on human mammary cancer and rabbit uterus. 255 Jan 22

Estrogen is known to stimulate the proliferation and basement membrane invasiveness of the MCF-7 human breast cancer cell line. We have compared the new steroidal antiestrogen ICI 164,384, the triphenylethylene 4-hydroxytamoxifen (OHT), and the benzothiophene LY 117018, for their effects on the proliferation and invasiveness of the MCF-7 cell line and its antiestrogen-resistant variant LY-2. While all three antiestrogens blocked the proliferative effects of 17 beta-estradiol on MCF-7 cells, OHT and LY 117018, but not ICI 164,384 stimulated their proliferation in the absence of estrogen. The proliferative effects of OHT and LY 117018 were blocked by ICI 164,384. Basement membrane invasiveness of MCF-7 cells was stimulated by 17 beta-estradiol and OHT, but not LY 117018 or ICI 164,384. Both ICI 164,384 and LY 117018 were able to block the invasiveness induced by either 17 beta-estradiol or OHT. The LY-2 antiestrogen-resistant variant of the MCF-7 cell line showed increased basal proliferation, and responded only slightly to estrogen. ICI 164,384, but not OHT or LY 117018 antagonized the effects of 17 beta-estradiol, but did not reduce proliferation below control levels. The LY-2 line was not resistant to the antiestrogenic effects of LY 117018 or ICI 164,384 on invasiveness, and was stimulated by LY 117018 for this parameter. Thus, ICI 164,384 is a pure antiestrogen for MCF-7 cell proliferation and invasiveness, and may offer clinical advantage over nonsteroidal antiestrogens which can stimulate these activities in tumor models in vitro.
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PMID:ICI 164,384, a pure antagonist of estrogen-stimulated MCF-7 cell proliferation and invasiveness. 258 35

Estrogen-producing activity of common epithelial tumors (54 cases) and metastatic tumors (4 cases) of the ovary was clinically and endocrinologically studied in postmenopausal patients. High serum concentrations of E1 (greater than or equal to 50 pg/ml) and E2 (greater than or equal to 30 pg/ml) were demonstrated in 78% in the group of postmenopausal patients. Mucinous tumors were more commonly associated with high estrogen levels than serous tumors. Patients with malignant tumors more frequently have a high level of serum estrogen than those with benign tumors. Estrogen decreased to normal after complete resection of the tumor, but returned to the abnormal range following a recurrence. The local-peripheral gradient of the estrogen level was noted by measuring the estrogen concentration in the blood of the affected ovarian and peripheral veins at the time of laparotomy. These results indicated that serum estrogen in the patient was originally produced in the ovarian tumor mass. The increased estrogen were reflected in such target tissues as the endometrium and vaginal mucosa. Proliferation, hyperplasia, atypical hyperplasia and even a case of carcinoma of the endometrium were observed in patients with ovarian tumors. An increase in the karyopyknotic index (KPI) of the vaginal smear, as well as uterine bleeding, could be an important signs of asymptomatic ovarian tumors in postmenopausal women.
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PMID:[Estrogen production in epithelial tumors of the ovary--clinical and endocrinological study in postmenopausal women]. 259 2


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