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51.
52.
Isolation and characterization of propagable cell lines (HUNC) from the androgen-sensitive Dunning R3327H rat prostatic adenocarcinoma 总被引:1,自引:0,他引:1
Presnell SC; Borchert KM; Glover WJ; Gregory CW; Mohler JL; Smith GJ 《Carcinogenesis》1998,19(4):585-590
The Dunning H rat prostate tumor (R3327H) is a widely used experimental
model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been
characterized as androgen-sensitive, androgen-receptor (AR) positive,
prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To
date, the tumor has been maintained by serial passage in vivo because of
the lack of an in vitro cell line that retains the characteristics of the
in vivo tumor. The objective of the present study was to establish a
propagable cell line from R3327H adenocarcinoma that maintained androgen
sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in
vivo R3327H tumor was dissociated with collagenase and placed into
Richter's improved media (with supplements). A cytokeratin-positive
epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line
(HUNC-S) were generated from the primary culture, subcultured continuously
for >300 days, and passaged >50 times. Survival of the HUNC-E cell
line in vitro depended on several media supplements, including
nicotinamide, insulin, transferrin, selenium and epidermal growth factor
(EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the
culture period, as confirmed by immunocytochemistry and Western blot
analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT)
to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent
growth and PSA production, which demonstrated the androgen-sensitive nature
of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1
ratio and introduced subcutaneously into syngeneic male hosts, tumors
formed in 2/3 animals with an average latency of 7 months. RT-PCR and
immunocytochemical characterization of the HUNC cell lines revealed that
the cells expressed several growth factors and their cognate receptors,
including HGF, TGF-alpha and the TGF-betas, indicating the establishment of
potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S
CaP cell lines, which retain the characteristics of the epithelial and
stromal components of the in vivo R3327H tumor, will allow a more thorough
and informative molecular and biological analysis of prostatic
adenocarcinoma.
相似文献
53.
Previous work has shown that sustained increased and decreased cell
proliferation, induced by dietary zinc deficiency and caloric restriction
respectively, influence the course of N- nitrosomethylbenzylamine
(NMBA)-induced esophageal carcinogenesis in rats. The present study
considered whether the increased cell proliferation and esophageal tumor
incidence induced by zinc deficiency are reversed upon zinc replenishment.
Weanling rats were maintained initially on a deficient diet containing 4
p.p.m. zinc. After 5 weeks, carcinogen-treated animals were given six
intragastric doses of NMBA (2 mg/kg twice weekly). Controls were untreated.
After the second NMBA dose, the rats were divided into three dietary
groups. One group was continued on the deficient diet, while the other two
groups were switched to diets containing either 75 or 200 p.p.m. zinc, with
half of the members in each group fed ad libitum and half pair-fed with
deficient rats. NMBA-untreated controls were similarly replenished. At
various time points, esophageal cell proliferation was assessed in five
animals from each group by immunohistochemical detection of cells in S
phase, with in vivo 5-bromo-2'deoxyuridine labeling. At 11 weeks after the
first dose, esophageal tumor incidence was greatly reduced, from 100% in
the deficient group to 26 and 14% respectively in the replenished groups
fed ad libitum 75 and 200 p.p.m. zinc and to 14 and 11% respectively in the
replenished groups pair-fed 75 and 200 p.p.m. zinc. In addition, the number
of tumors per esophagus was reduced from 9.93 +/- 4.25 in deficient rats,
to a range of 0.11 +/- 0.31-0.30 +/- 0.54 in replenished animals. Following
zinc replenishment, esophageal cell proliferation, as measured by labeling
index (LI), the number of labeled cells and the total number of cells, was
markedly decreased in NMBA-untreated and -treated esophagi as compared with
those in corresponding deficient esophagi. Thus, the esophageal cell
proliferation induced by zinc deficiency is reversed by zinc replenishment
and replenished animals have a markedly lower incidence of esophageal
tumors.
相似文献
54.
55.
Previous immunohistochemical studies in mouse, rat, and chick have reported that the expression of the glycoprotein and cell adhesion molecule L1, a member of the immunoglobulin superfamily, shows regulation during development of retina and optic nerve. To extend our understanding of the role of L1 in developing neural circuitry, we have examined L1 expression in the optic tract and thalamic and midbrain synaptic targets of retinal fibers in the early postnatal Syrian hamster, a well-characterized developmental model of the primary visual projection. Metabolic labeling studies reveal that a synaptically targeted, sulfated, and glycosylated form of L1 undergoes rapid axonal transport from the retina. Retinofugal transport of L1 decreases commensurate with the decline in immunoreactivity of retinal fibers in the visual pathway. Retinal ganglion cell axons show intense L1 immunoreactivity as they navigate in highly fasciculated bundles in the optic tract overlying the lateral geniculate body and in the superior colliculus. We found no evidence of L1 immunoreactivity on retinal axon collaterals as they defasciculate from the optic tract and branch into target neuropils. L1 immunoreactivity wanes in optic tract as axon terminal arbors are elaborated in the lateral geniculate body and superior colliculus and as myelination in the visual pathway commences. This pattern of L1 expression suggests that, in the early postnatal period, L1 may support fasciculation of retinal fibers, maintaining them within the optic tract, and that subsequent down-regulation of L1 may facilitate their terminal arborization and myelination. 相似文献
56.
Jiménez-Bonilla J Maldonado A Morales S Salud A Zomeño M Román J Belon J Moya F 《Clinical positron imaging : official journal of the Institute for Clinical P.E.T》2000,3(6):231-236
Purpose: To retrospectively evaluate the contribution of 18F-fluorodeoxy-glucose-positron emission tomography (FDG-PET) to the diagnosis and clinical management of patients who were suspected of recurrent ovarian carcinoma, based on elevated tumor markers levels with normal or equivocal computed tomography (CT) or nuclear magnetic resonance (NMR).Procedures: 20 patients with these characteristics underwent FDG-PET. PET findings were confirmed in 14, in 7 by surgery, and in the other 7 by clinical course.Results: Recurrence was confirmed in 12 patients, all with FDG-PET positive. In other 2, recurrence was rule out and in 1, FDG-PET was negative. FDG-PET accuracy was 93% with 4 surgeries avoided and guided other 6.Conclusions: FDG-PET is an useful technique for detecting recurrent ovarian carcinoma suspected by elevated tumor markers levels and normal or equivocal results in the morphologic imaging techniques and has an important clinical impact on the management of these patients. 相似文献
57.
58.
Emily Banks Gillian Reeves Valerie Beral Diana Bull Barbara Crossley Moya Simmonds Elizabeth Hilton Stephen Bailey Nigel Barrett Peter Briers Ruth English Alan Jackson Elizabeth Kutt Janet Lavelle Linda Rockall Matthew G Wallis Mary Wilson Julietta Patnick 《British medical journal》2004,328(7451):1291-1292
59.
Objectives: Despite prevailing beliefs about the potential benefits and harmfulness of mindfulness for people who hear voices, there is a paucity of research into staff and service user views. Q-methodology was used to explore views about mindfulness groups for voice-hearers. Method: Opportunistic sampling of mental healthcare staff (N?=?14) and service users with psychosis (N?=?17). Both samples were analysed using principle components factor analysis to identify the range of attitudes held by staff and service users. Results: Staff participants were particularly knowledgeable and interested in mindfulness. A single staff consensus factor was found suggesting mindfulness is helpful, and not harmful for mental health, but uncertainty surrounded its usefulness for voice-hearers. Service users held four distinct attitudes: (i) mindfulness helps to calm a racing mind; (ii) mindfulness helps to manage stress; (iii) mindfulness improves well-being, and does not alter the brain, reality beliefs, or cause madness; and (iv) mindfulness helps with managing thoughts, fostering acceptance, and is acceptable when delivered in a group format. Conclusions: Staff viewed mindfulness groups for psychosis as helpful, not harmful, but were uncertain about their utility. Consistent with previous research, service users viewed mindfulness groups as useful to promote well-being and reduce distress for individuals experiencing psychosis. 相似文献
60.