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Breast cancer micrometastases: Different interactions of carcinoma cells with normal and cancer patients' bone marrow stromata 总被引:6,自引:1,他引:6
Nicola MH Bizon R Machado JJ Sollero T Rodarte RS Nobre JS Magalhães MM Takiya CM Borojevic R 《Clinical & experimental metastasis》2003,20(5):471-479
The apparently dormant breast cancer micrometastases in haemopoietic marrow are correlated with distant metastatic carcinoma
dissemination. We studied in vitro interactions of carcinoma cells with adjacent stromata, using connective tissue cell cultures from breast and bone marrow
samples of normal donors, comparing them to the pericancerous breast tissue and bone marrows of 12 selected patients with
invasive breast carcinomas. Cancer cells were detected by immunocytochemistry and RT-PCR in all the bone marrows and in most
blood samples of the studied patients. We monitored the growth and interaction of carcinoma MCF-7 cells with the stromata.
The normal breast stroma sustained typical massive cancer growth. The pericancerous breast stroma induced the invasive mesenchymal
pattern of growth. Normal bone marrow stroma induced the same conversion and was highly adhesive, retaining the cells in the
stroma, but carcinoma patients' bone marrow stromata underwent low adhesive interactions with cancer cells, releasing them
potentially into the circulation. The semi-quantitative RT-PCR indicated an enhanced expression of the hepatocyte growth factor
and its receptor c-met in breast and bone marrow stromata of cancer patients. The input of cancer cells into the normal bone marrow may induce modifications
of the local microenvironment, favourable for growth and release of carcinoma cells into the systemic circulation, which correlate
with the poor prognosis of patients with bone marrow micrometastases.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Presymptomatic diagnosis in Portuguese FAP families using intragenic RFLPs and (CA)n flanking markers by fluorescence based semiautomated DNA analysis.
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R Almeida P Fidalgo E Ramalho A Brás N Leit?o C Mira J Rueff C Monteiro 《Journal of medical genetics》1996,33(3):244-247
Owing to the large size of the APC gene, responsible for familial adenomatous polyposis, direct screening for individual mutations is not a practical approach. In the present study we establish the methodology of fluorescence based semi-automated DNA analysis to perform presymptomatic diagnosis of members at risk from 11 Portuguese FAP families with three (CA)n markers flanking the APC gene, MBC, CB26, and YN5.64, and four intragenic RFLPs. Haplotypes were constructed on the basis of individual genotypes and their segregation through generations were followed. The study was informative for 12% of subjects using only intragenic RFLPs and increased to 90% when we used the three (CA)n flanking markers. We report two of the 11 families under study in our laboratory and show recombinant events leading to a precise localisation of the CB26 marker between D5S82 and the APC gene. In one family there was a loss of (CA) units of one allele of the CB26 marker from an unaffected mother to her son. 相似文献
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Cardoso O Leitão R Figueiredo A Sousa JC Duarte A Peixe LV 《Microbial drug resistance (Larchmont, N.Y.)》2002,8(2):93-97
Resistance to carbapenems is emerging, and it is a great problem to therapeutics. Three isolates of Pseudomonas aeruginosa from a Portuguese hospital identified in urine and sputum, in 1995, presented a high-level resistance to imipenem (> 32 mg/L). Afterward, one isolate of P. aeruginosa recovered from urine of an ambulatory patient in 1998 showed high resistance to imipenem and meropenem. The resistance to carbapenems in these strains was associated with the production of a class B beta-lactamase, as was demonstrated by imipenem hydrolysis and inhibition by EDTA. Using primers described for bla(IMP) and bla(VIM), the amplification of the latter was observed in all isolates and a VIM-2 metallo-enzyme was identified. The pulsed-field gel electrophoresis (PFGE) patterns of these isolates were indistinguishable, suggesting dissemination to the community of this VIM-2 producer. 相似文献
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Analysis of human papillomavirus prevalence and TP53 polymorphism in head and neck squamous cell carcinomas 总被引:1,自引:0,他引:1
Cortezzi SS Provazzi PJ Sobrinho JS Mann-Prado JC Reis PM de Freitas SE Filho JF Fukuyama EE Cordeiro JA Cury PM Maniglia JV Villa LL Tajara EH Rahal P 《Cancer Genetics and Cytogenetics》2004,150(1):44-49
Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa from 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors. 相似文献
8.
Evangelista André Nobre dos Santos Flávia Franciele de Oliveira Martins Lorena Pacheco Gaiad Thais Peixoto Machado Alex Sander Dias Rocha-Vieira Etel Costa Karine Beatriz Santos Ana Paula Oliveira Murilo Xavier 《Lasers in medical science》2021,36(6):1201-1208
Lasers in Medical Science - The aim of the present study was to investigate the effects of photobiomodulation (PBM) therapy on the expression of heat shock protein 70 (HSP70) and tissue repair in... 相似文献
9.
Mathematical location models have been increasingly applied in the health services at the international level. In Brazil, although incipient, there exists an enormous potential for the use of such models in the area of public health. In this paper several location models that can be applied to public health are presented initially, and the location of non-emergency services, of emergency services and of services hierarchically related are analysed. A hierarchical model is then applied to the location of maternal and perinatal assistance in the municipality of Rio de Janeiro. In this part, after presenting some related data for the municipality, a four-level hierarchical model (location of out-patient units, maternity hospitals, neonatal hospitals and general hospitals) is proposed and the impact that the adoption of this methodology would have as compared with that of the present system is analysed. 相似文献
10.
The impact of oral rehydration therapy (ORT) on the recent decline in diarrhoea mortality in the northeast of Brazil was studied. Proportionate infant mortality fell from 32% in 1980 to 17% in 1989 and infant deaths attributed to diarrhoea dropped from 41% to 25%, resulting in an overall reduction of 57%. Similar decreases were observed for children aged 1-4 years. Diarrhoea admissions also fell from 57% of infant hospitalizations in 1980 to 30% in 1990. None of the other major causes of death or admissions showed such decline. ORT was introduced in the early 1980s, being used in 35% of all episodes in 1991 and in 62% of those regarded as severe by the mother. Other changes included a worsening of socioeconomic conditions and increases in water supply, vaccine coverage, breastfeeding duration and nutritional status. A simulation model estimated that changes in factors other than ORT would lead to a 21% reduction in infant diarrhoea mortality, or about one-third of the actual decline. Finally, an ecological analysis showed that ORT use rates were inversely correlated to infant diarrhoea mortality (r=-0.61; p=0.04). Despite the shortcomings of the available data, these findings suggest an important impact of ORT on diarrhoea mortality. 相似文献