Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Okadaic acid (OA), a potent mouse skin tumor promoter and inhibitor of the protein phosphatases 1 and 2A, was investigated for its effects on the expression of tumor-associated early and secondary response genes in mouse keratinocytes. Adult mice were treated topically with 12.5 nmol of OA, and the steady-state levels of various gene transcripts in the skin were determined at different times after treatment. The nuclear proto-oncogenes c-fos and c-jun are referred to as early response genes because the classical tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) induces their expression to maximal levels within 2 h after treatment. OA induced the expression of c-fos 2-72 h after treatment, with two peaks at 6 and 48 h. The steady-state level of expression of c-jun was relatively high in untreated skin, and OA induced a slight increase in its expression from 12 to 48 h after treatment. Transin and plasminogen-activator (PA) urokinase, whose induced expression peaks at least 4 h after TPA treatment, are referred to as secondary response genes. OA induced their expression more slowly than TPA. In mouse papilloma cell line 308, OA induced higher and more sustained steady-state levels of c-jun and c-fos than an equimolar dose of TPA. Transin and PA-urokinase were induced to similar levels by TPA and OA in 308 cells; however, the induction of these genes by OA was slower than induction by TPA. The existence of different patterns of induced expression of early and secondary response genes by OA and TPA suggests that these tumor promoters affect gene expression in mouse keratinocytes through different pathways.
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PMID:Okadaic acid induces the expression of both early and secondary response genes in mouse keratinocytes. 154 37

On the basis of reports of rat mammary- and pancreas-tumor models, we hypothesized that an increase in consumption of linoleic acid (LA) would also cause an enhancement in mouse skin-tumor promotion. SEN-CAR mice were placed on diets containing 0.8%, 2.2%, 3.5%, 4.5%, 5.6%, 7.0%, or 8.4% LA, 1 week after initiation with 7,12-dimethylbenz(a)anthracene and 3 weeks before starting promotion with 12-O-tetradecanoylphorbol-13-acetate. An inverse correlation (r = -0.92) was observed between papilloma number and level of LA; however, there was little difference in tumor incidence. A relationship between diet and carcinoma incidence was also found. The fatty acid composition of epidermal phospholipids reflected the dietary LA levels. 12-O-Tetradecanoylphorbol-13-acetate-induced epidermal prostaglandin E2 levels generally decreased with increasing dietary LA. To determine whether this inverse correlation between dietary LA and tumor yield was due to species differences or organ-model differences, a mammary carcinogenesis experiment was performed. SENCAR mice were fed the 0.8%, 4.5%, and 8.4% LA diets. All mice received 6 mg 7,12-dimethylbenz(a)anthracene, administered intragastrically at 1 mg/week. Tumor appearance was delayed in the 0.8% LA diet group, and a positive dose-response relationship between dietary LA and mammary-tumor incidence was observed. These studies suggest that the effect of dietary LA on tumor development is target tissue specific rather than species specific.
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PMID:Differential effects of dietary linoleic acid on mouse skin-tumor promotion and mammary carcinogenesis. 154 40

A case of inverted papilloma of the posterior urethra is reported. A 59-year-old male was admitted with the chief complaint of hematuria. Urethrogram revealed a small defect in the neck of the bladder. Endoscopic examination revealed a polypoid tumor on the stalk arising from prostatic urethra, and transurethral resection was performed. The patient has been subsequently followed up and there has been no evidence of recurrence. Although 141 cases of inverted papilloma have been reported in many anatomical sites of the urinary tract, only 19 cases involving the posterior urethra have been described in Japan. This is the 20th case of a posterior urethra.
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PMID:[A case report of inverted papilloma of the posterior urethra]. 156 60

The mortality rate of nonmelanoma skin cancer is higher than generally considered. An actual nonmelanoma skin cancer is a risk factor not only for other skin cancers but also for cancers in other organs. The recurrence rate can, according to the method of calculation, yield surprisingly diverging results. Statistical mapping of subclinical tumor growth in basal cell carcinoma supplies the margins for tumor-free excision. An even better but more expensive tool for therapy planning is tumor imaging with magnetic resonance imaging. Psoralen plus ultraviolet light of the A wavelength-treated patients run a dose-dependent risk of developing squamous cell carcinoma of the skin but also cancers in other organs. Human papilloma virus-16 seems not to be associated with squamous cell carcinoma of the skin except for the anogenital region and possibly the finger. The finding of retroviruslike particles in endemic non-acquired immunodeficiency syndrome Kaposi's sarcoma strongly suggests that a virus other than human immunodeficiency virus may play a role in the pathogenesis of this disease.
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PMID:Basal cell and squamous cell carcinoma and Kaposi's sarcoma. 159 11

Focal pulmonary masses in children encompass a spectrum of conditions including congenital lesions, inflammatory masses, hematomas, and benign and malignant tumors. Congenital masses include bronchial atresia, sequestration, cystic adenomatoid malformation, and pulmonary vascular anomalies. Inflammatory masses most commonly result from infection and include pulmonary abscess, granulomas, and postinflammatory pseudotumors. Blunt trauma can cause a hematoma, which decreases in size on serial radiographs. Pulmonary neoplasms may be benign such as papilloma, hamartoma, and bronchial carcinoid tumor (low-grade malignancy), or they may be malignant as in sarcoma, carcinoma, and pulmonary blastoma. Because computed tomography (CT) is the most sensitive technique in detecting and helping characterize parenchymal disease, it has become the procedure of choice for further investigation of lesions seen or suggested on plain chest radiographs. Understanding the CT appearance of these lesions can allow an accurate diagnosis and optimize management of the patient's condition.
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PMID:CT of focal pulmonary masses in childhood. 160 41

Twenty-one cases of inverted papilloma of the renal pelvis have been described in the literature. A 71-year-old man was admitted to our hospital to examine a right renal mass. We diagnosed a right renal tumor on the basis of the findings from excretory urogram (IVP), computerized tomography (CT) and magnetic resonance imaging (MRI). Surgical material revealed an inverted papilloma in the renal pelvis. We report on the first case of an invested papilloma of the renal pelvis associated with renal cell carcinoma.
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PMID:Inverted papilloma of the renal pelvis associated with renal cell carcinoma: a case report. 160 66

The etiology of esophagus papilloma is much debated: some authors attach greater importance to irritation factors, while others give preference to the viral hypothesis and suggest that this disease could eventually lead to squamous cell carcinoma of the esophagus. To verify the viral hypothesis, we reviewed the histological slides of the 33 cases of esophageal papilloma diagnosed in our Institute of Pathology between 1973 and 1988. We evaluated the histological diagnosis using Winckler's criteria. HPV typing was done using probes of HPV DNA types 6-11, 16-18, 31-33-35 applied to paraffin sections according to the in-situ hybridization method. Clinical and endoscopic data of 15 cases (from the CHUV) are reviewed. Oncological data was provided by the Vaud Cantonal Tumor Register. No patient in our series fulfilled all the histological criteria set by Winckler to diagnose an HPV condition. Viral DNA 31-33-35 was found in a small minority of the papillomas. The clinical impact of esophageal papilloma on epidermoid carcinogenesis is nil.
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PMID:[Is papilloma of the esophagus a preneoplastic lesion? Study of 33 cases]. 164 49

Shope papillomas induced by cottontail rabbit papilloma-virus (CRPV) in domestic rabbits frequently regress spontaneously or, failing to do so, convert into squamous cell carcinomas at a high rate. This papilloma-carcinoma complex in rabbits provides an experimental model for human papillo-mavirus-associated malignancies. The aim of this study was to prepare an experimental system in inbred rabbits by establishing culture cell lines of the tumor. Squamous cell carcinoma developed from a Shope papilloma that had been induced 6 months previously by inoculating CRPV into an inbred B/J rabbit. By in vitro culturing of the tumor cells, cell lines with potentials for terminal differentiation and tumorigenicity were established. Cloning yielded sublines that varied in these potentials and possessed episomal and integrated CRPV genomes as revealed by Southern hybridization in both one- and two-dimensional electrophoresis. Major CRPV-specific transcripts were similarly observed both in well-differentiated and in poorly differentiated sublines. Immunofluorescence with syngeneic rabbit antibody against tumor-specific antigens localized such antigens mainly in the nuclei of the cells of these sublines. This experimental system allows experiments that were not feasible in randomly bred rabbits.
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PMID:Establishment from Shope carcinoma induced in an inbred rabbit of culture cell lines with various potentials for differentiation and tumorigenicity. 164 30

Tumour viruses are thought to contribute to the development of one fifth of all human cancers, although the mechanisms involved are still obscure. Human papilloma virus (HPV) is a DNA virus associated with oral carcinomas. It has been shown that virus DNA has to become integrated into cellular DNA in order to transform normal to malignant cells. Cellular oncogenes and tumour suppressor genes are potential cancer genes. They are involved in the control of growth and differentiation of normal cells. It is known that structural or regulatory changes (activation) of these genes will lead to malignant transformation. Virus integration will sometimes take place in close relation to cellular oncogenes. Such incorporation may result in oncogene activation. Other cellular factors that may contribute to the development of oral squamous cell carcinoma are also discussed.
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PMID:[Can virus cause oral cancers?]. 165 Apr 50

Congenital brain tumors have been reported infrequently and their management remains ill defined. An 11-year review (1977-1987) of all children with brain tumors with the onset of symptoms before 1 year of age was completed. Twenty-two children with the following histological diagnoses were treated: astrocytoma (7 patients), primitive neuroectodermal tumor (6 patients), papilloma or carcinoma of the choroid plexus (3 patients), malignant teratoma (2 patients), dermoid tumor (2 patients), embryonal rhabdomyosarcoma (1 patient), and chloroma (1 patient). Fifteen tumors were supratentorial in location, and 7 were infratentorial. Initial symptoms were hydrocephalus (32%), focal neurological deficit (23%), asymptomatic increase in head circumference (18%), failure to thrive (14%), and seizures (4.5%). The goal of treatment was a radical excision when possible, with primary chemotherapy in the last 6 years of the review period. Radiation therapy was the adjunct to surgery in the initial 5-year period. All patients with papillomas of the choroid plexus and dermoid lesions underwent a total resection with no recurrence. All 7 astrocytomas were supratentorial, with 6 occurring in the diencephalon. Five of the seven patients with astrocytomas survived more than 5 years. The 6 primitive neuroectodermal tumors were located equally between the supra- and infratentorial spaces. Four of the 6 infants with these tumors received chemotherapy (2 received chemotherapy alone; 2 received chemotherapy and radiation therapy) and are tumor free 2 to 9 years later. A fifth child received radiation therapy alone early in the series and survived only 4 months. The family of the other child refused adjunctive treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Brain tumors occurring before 1 year of age: a retrospective reviews of 22 cases in an 11-year period (1977-1987). 165 61


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