| 21. |
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| 22. |
- Saeter, G, et al.
(författare)
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Prognostic factors in bone sarcomas
- 1997
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Ingår i: Acta Orthopaedica Scandinavica. Supplementum. - 0300-8827. ; 68:273, s. 156-160
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Tidskriftsartikel (refereegranskat)abstract
- Based on a literature review and the SSG experience, the most important prognostic factors in high-grade osteosarcoma appear to be the presence of detectable metastases at diagnosis, tumour volume, old age, sex, histologic response, and possibly tumoral P-glycoprotein expression. However, for an adolescent patient with non-metastatic extremity disease, there is no consensus regarding prognostic factors at initial presentation, and currently there is thus no established method for dividing them into high- and low risk groups for the purpose of treatment differentiation. It should also be remembered that available prognostic factors have been identified only in a retrospective manner, following aggressive treatment of all patients. Thus patients in "favourable" prognostic groups may simply be patients who have had a good effect from aggressive treatment, and how they would have done with reduced treatment remains to be shown. Obviously the best method for prognostication would be the direct demonstration of micrometastatic disease in the lungs or in peripheral blood. In the relatively near future, this may become possible with immunoscintigrapy or immunohistochemistry utilizing monoclonal antibodies [29-31]. In Ewing's sarcoma, the most powerful factors indicating poor prognosis are metastases at diagnosis, poor histologic response, large tumour size and possibly pelvic localisation. There appears to be a somewhat better international consensus regarding prognostic factors in Ewing's sarcoma than in osteosarcoma. Although several studies have implemented intensified treatment for poor prognostic groups [8, 32], the role (if any) of high-dose treatment with stem cell rescue remains to be proven. The same factors are prognostic both for the development of metastases and local recurrence, but in addition, surgical treatment as opposed to radiotherapy appears to reduce local failure rate [12, 17, 33, 34]. As in osteosarcoma, the near future offers promise regarding the detection and quantification of micrometastatses and minimal residual disease, by means of PCR techniques recognizing specific genetic changes in the Ewing family of tumors [35].
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| 23. |
- Westberg, G, et al.
(författare)
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Secretory patterns of tryptophan metabolites in midgut carcinoid tumor cells.
- 1997
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Ingår i: Neurochemical research. - 0364-3190. ; 22:8, s. 977-83
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Tidskriftsartikel (refereegranskat)abstract
- Hormonal overproduction is a significant problem in patients with disseminated midgut carcinoid tumors. Serotonin (5-HT) is one major product secreted from such tumors and the urinary excretion of its metabolite (5-hydroxyindoleacetic acid, 5-HIAA) serves as an important tumor marker. The present study aimed at elucidating mechanisms of tryptophan metabolite secretion to facilitate the treatment of the carcinoid syndrome. When midgut carcinoid tumors were studied in primary cell cultures, several similarities with adrenergic neurons could be demonstrated. A marked dose-dependent depletion of intracellular 5-HT could be induced by reserpine, and monoamine oxidase-activity was revealed both in functional studies and by immunocytochemistry. Differences between tumors in the ratios of tryptophan metabolites released indicated that enzymes for synthesis and degradation of 5-HT were individually expressed. Treatment with the somatostatin analogue octreotide or with dexamethasone decreased the extracellular levels of tryptophan metabolites, but the mechanisms were partly different. In some tumors octreotide also decreased the synthesis of 5-HT, while dexamethasone markedly increased the intracellular 5-HIAA levels. It is of clinical interest to further elucidate these mechanisms, since the two drugs may have complementary actions in carotid crisis reactions.
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| 24. |
- Mellander, Stefan, et al.
(författare)
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Cardiovascular regulation by endogenous nitric oxide is essential for survival after acute haemorrhage
- 1997
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Ingår i: Acta Physiologica Scandinavica. - 0001-6772. ; 160:1, s. 57-65
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Tidskriftsartikel (refereegranskat)abstract
- Our previous studies have indicated that endogenous nitric oxide serves as a physiologically important inhibitor of vascular tone during acute haemorrhage. This vasodilator action attenuates the concomitant reflex adrenergic constriction and thereby prevents critical reduction of tissue blood flow. The present study aimed to evaluate the overall importance of this nitric oxide regulation for survival after acute haemorrhage. This was done by comparative observations of survival time and circulatory, metabolic and histopathological changes after an acute standardized lethal blood loss (45%) in cats exposed to nitric oxide synthase (NOS) inhibition and in matched control animals with intact nitric oxide regulation. NOS inhibition was instituted by intravenously administered N omega-nitro-L-arginine methyl ester. The survival time averaged 2 h 49 min in the NOS-blocked animals and 10 h 14 min in the control animals (P < 0.001). NOS inhibition thus reduced the posthaemorrhagic survival time to < 30% of that in the control cats. Haemorrhage in the NOS-blocked animals led to rapidly developing arterial hypotension, increased anaerobic metabolism, metabolic lactacidosis, hyperkalaemia, and morphological tissue damage especially in heart and liver, in spite of maintained arterial normoxia, which signifies tissue hypoxia caused by seriously impaired nutritional blood supply. At the time of death of the NOS-blocked cats, the control animals still exhibited a virtually normal circulatory/metabolic state. A much later, and more slowly developing circulatory/metabolic deterioration was observed in the control animals. These differences between the two groups of animals indicate that nitric oxide release, by its vasodilator action, to a significant extent helps to maintain an adequate nutritional blood supply to the tissues in acute haemorrhage.
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| 25. |
- Bratt, O, et al.
(författare)
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Sons of men with prostate cancer : their attitudes regarding possible inheritance of prostate cancer, screening, and genetic testing
- 1997
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Ingår i: Urology. - 0090-4295. ; 50:3, s. 5-360
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To study attitudes regarding possible inheritance of prostate cancer among sons of men with prostate cancer.METHODS: A questionnaire was sent to 69 men with prostate cancer and their 101 unaffected sons. All participants were also interviewed by telephone. Sociodemographic data were collected, as were data about the fathers' disease.RESULTS: The response rate was high; 100 sons (99%) and 65 fathers (94%) answered all questions. Sixty of the sons claimed they had worries about having an increased risk of prostate cancer due to possible inheritance. About 90% of the sons wanted to know whether prostate cancer was inheritable (66 definitely and 24 probably), were positively inclined to undergo screening (65 definitely and 27 probably), and to undergo genetic testing (50 definitely and 41 probably), provided there had been multiple cases of prostate cancer in their family. An interest to know whether prostate cancer could be inherited was more frequent among sons with less than 12 years of education, worries about inheritance, younger age, a father treated with curative intent, and with children of their own, especially if sons. Interest in genetic testing was associated with less than 12 years of education and with worries about inheritance.CONCLUSIONS: A large majority of healthy men with a family history of prostate cancer were interested in knowing whether the disease could be inherited and were positively inclined to undergo screening and genetic testing. Our findings indicate that genetic counseling and a screening program could have beneficial psychological effects in families with multiple cases of prostate cancer.
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| 26. |
- Heidtmann, Hans-Heinrich, et al.
(författare)
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Cathepsin B and cysteine proteinase inhibitors in human lung cancer cell lines
- 1997
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Ingår i: Clinical and Experimental Metastasis. - 1573-7276. ; 15:4, s. 368-381
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Tidskriftsartikel (refereegranskat)abstract
- Cell lines derived from human squamous cell (EPCL), large cell (LCLC), and small cell lung cancer (SCLC) lines were investigated for the expression of cathepsin B (Cat B) and cysteine proteinase inhibitors (CPIs). The EPLC and LCLC lines expressed 5- to 50-fold more Cat B activity and contained more mature Cat B of M(r) 27-29 kDa (> 2.5 microg/mg total protein) than the SCLC lines (< 1.0 microg/mg total protein). The LPLC lines also secreted the highest amounts of Cat B precursor of M(r) about 46 kDa. Inhibitory activities against Cat B and papain were associated with high molecular mass (HMM) and low molecular mass (LMM) inhibitory proteins, both in cell extracts and in media. About 75% of the inhibitory activity was associated with HMM inhibitors, the majority of which were kininogens (M(r) > or = 67 kDa). The LMM inhibitors of M(r) 10-15 kDa were cystatin C and stefins A and B, which were quantitated by ELISA: stefins A and B were present in cell extracts and medium in similar concentrations (5-200 ng/10(6) cells), while 80-99% of the cystatin C was released in the medium (10-195 ng/10(6) cells). Phorbol ester (PMA), which induces protein-kinase C mediated signal transduction and enhances cellular differentiation in many non-small cell lung cancer (NSCLC) cell lines, increased intracellular Cat B activity and Cat B protein as well as its secretion in some cell lines but not in others, regardless of their histological type. PMA significantly (P < 0.049) decreased intracellular stefin A concentrations in two EPLC lines and non-significantly in two LCLC lines. PMA decreased secretion of stefin A in all EPLC lines, but not in LCLC lines, while IGF-I significantly increased stefin B secretion in both SCLC lines. These data showed that lung tumor cells produce both cysteine proteinases and cystatins. As the antagonistic molecules are regulated differently in histologically different types of lung tumor cells, it is possible that an imbalance between the proteinases and their specific inhibitors plays a role in progression of certain types of lung tumors in vivo.
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| 27. |
- Lenner, Per, et al.
(författare)
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Excess Mortality from Breast Cancer in Relation to Mammograpy Screening in Northern Sweden
- 1997
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Ingår i: Journal of Medical Screening. - : Sage Publications. - 0969-1413 .- 1475-5793. ; 4:1, s. 6-9
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Tidskriftsartikel (refereegranskat)abstract
- Objectives—Previous randomised studies of mammography screening have shown a significant effect on breast cancer mortality, particularly in women aged 50–Q69 at randomisation. Breast cancer mortality has traditionally been studied by judgments on causes of death, either from cause of death registers or from medical records. In this study an alternative method was used, estimating the excess mortality associated with breast cancer.Setting—In 1990 two counties of northern Sweden started population based mammography screening of women aged 40–74. The unscreened population in the two other counties of the same region were selected as controls.Results—Excess mortality associated with breast cancer was lower in the screened population, and was discernible three to four years after the start of screening. The relative risk estimate, based on the cumulative excess number of deaths from breast cancer during 1990–95 in the screened versus the control population aged 40–74 (at diagnosis of breast cancer), was 0.72 (95% confidence interval (CI) 0.53 to 0.99). For women aged 50–69 it was 0.67 (95% CI 0.46 to 0.99). In the 50–69 age group the estimated excess number of deaths from breast cancer during 1995 was 17.0 per 100 000 women (95% CI 5.0 to 29.0) in the screened counties and 51.1 per 100 000 (95% CI 30.2 to 71.9) in the unscreened counties.Conclusions—Population based routine screening has substantial effects on breast cancer mortality in women aged 50–69. Estimation of excess mortality can be used in future studies to evaluate the effects of mammography screening on breast cancer mortality.
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| 28. |
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| 29. |
- Jóhannsson, O T, et al.
(författare)
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Tumour biological features of BRCA1-induced breast and ovarian cancer
- 1997
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Ingår i: European Journal of Cancer. - 0959-8049. ; 33:3, s. 362-371
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Tidskriftsartikel (refereegranskat)abstract
- BRCA1 mutations, although implicated in disease predisposition in a major part of the hereditary breast cancer population, do not seem to be crucially involved in tumorigenesis of sporadic breast and ovarian cancers. This suggests that tumours arising in BRCA1 mutation carriers may differ from BRCA1 negative hereditary and sporadic cancer in genetic and biological features, as well as in clinical behaviour. Prior to BRCA1 analysis, 79 breast and 19 ovarian tumours from 57 breast and breast-ovarian cancer families, and 170 tumours from a comparison group of stage II breast cancers were studied with regard to histopathological features; immunohistochemistry [c-erbB-2, p53, oestrogen receptor (ER) and progesterone receptor (PR)], DNA flow cytometry and S-phase fraction. BRCA1 mutations were found in 40 breast and 15 ovarian tumours. The BRCA1 positive breast tumours were significantly more often of ductal type, histological grade III and manifested a heavy lymphocyte infiltration. Additionally, as compared to BRCA1 negative tumours, the BRCA1 positive tumours were significantly more often ER, PgR and c-erbB-2 negative. Furthermore, they were significantly more often DNA non-diploid, as well as being characterised by higher S-phase fraction values. These results suggest that BRCA1-induced breast cancers may manifest distinct tumour biological features of clinical importance.
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| 30. |
- Tirkkonen, M, et al.
(författare)
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Distinct somatic genetic changes associated with tumor progression in carriers of BRCA1 and BRCA2 germ-line mutations
- 1997
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Ingår i: Cancer Research. - 0008-5472. ; 57:7, s. 7-1222
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Tidskriftsartikel (refereegranskat)abstract
- BRCA1 and BRCA2 mutations confer increased risk for development of breast cancer, but a number of additional, currently largely unknown, somatic genetic defects must also accumulate in the breast epithelial cells before malignancy develops. To evaluate the nature of these additional somatic genetic defects, we performed a genome-wide survey by comparative genomic hybridization on breast cancers from 21 BRCA1 mutation carriers, 15 BRCA2 mutation carriers, and 55 unselected controls. The total number of genetic changes was almost two times higher in tumors from both BRCA1 and BRCA2 mutation carriers than in the control group. In BRCA1 tumors, losses of 5q (86%), 4q (81%), 4p (64%), 2q (40%), and 12q (40%) were significantly more common than in the control group (7-13%). BRCA2 tumors were characterized by a higher frequency of 13q (73%) and 6q (60%) losses and gains of 17q22-q24 (87%) and 20q13 (60%) as compared to the prevalence of these changes in the control group (12-18%). In conclusion, accumulation of somatic genetic changes during tumor progression may follow a unique pathway in individuals genetically predisposed to cancer, especially by the BRCA1 gene. Activation or loss of genes in the affected chromosomal regions may be selected for during tumor progression in cells lacking functional BRCA1 or BRCA2. Identification of such genes could provide targets for therapeutic intervention and early diagnosis.
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