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991.
Lilia Suárez María-Belén Vidriales José García-Lara?a Guillermo Sanz María-José Moreno Antonio López Susana Barrena Rafael Martínez Mar Tormo Luis Palomera Esperanza Lavilla Ma Consuelo López-Berges María de Santiago M Encarnación Pérez de Equiza Jesús F San Miguel Alberto Orfao 《Clinical cancer research》2004,10(22):7599-7606
Myelodysplastic syndromes and acute myeloid leukemia (AML) are heterogeneous disorders in which conflicting results in apoptosis and multidrug resistance (MDR) have been reported. We have evaluated by multiparameter flow cytometry the expression of apoptosis- (APO2.7, bcl-2, and bax) and MDR-related proteins [P-glycoprotein (P-gp), multidrug resistance protein (MRP), and lung resistance protein (LRP)] specifically on bone marrow (BM) CD34+ cells, and their major CD32-/dim and CD32+ subsets, in de novo AML (n=90), high-risk myelodysplastic syndrome (n=9), and low-risk myelodysplastic syndrome (n=21) patients at diagnosis, and compared with normal BM CD34+ cells (n=6). CD34+ myeloid cells from AML and high-risk myelodysplastic syndrome patients displayed higher expression of bcl-2 (P <0.0001) and lower reactivity for APO2.7 (P=0.002) compared with low-risk myelodysplastic syndrome and normal controls. Similar results applied to the two predefined CD34+ myeloid cell subsets. No significant differences were found in the expression of P-gp, MRP, and LRP between low-risk myelodysplastic syndrome patients and normal BM, but decreased expression of MRP (P <0.03) in AML and high-risk myelodysplastic syndromes and P-gp (P=0.008) in high-risk myelodysplastic syndromes were detected. Hierarchical clustering analysis showed that low-risk myelodysplastic syndrome patients were clustered next to normal BM samples, whereas high-risk myelodysplastic syndromes were clustered together and mixed with the de novo AML patients. In summary, increased resistance to chemotherapy of CD34+ cells from both AML and high-risk myelodysplastic syndromes would be explained more appropriately in terms of an increased antiapoptotic phenotype rather than a MDR phenotype. In low-risk myelodysplastic syndromes abnormally high apoptotic rates would be restricted to the CD34- cell compartments. 相似文献
992.
卵巢癌高频转移细胞模型中nm23-H1基因表达的相关性研究 总被引:1,自引:0,他引:1
目的 筛选高频转移卵巢恶性肿瘤细胞,研究不同转移潜能的细胞和nm23的相关性。方法 通过反复动物接种和体外培养,观察动物肺转移状况,筛选高频转移细胞株,比较原发肿瘤和转移肿瘤的特征,并应用Northera-blot方法测定各类肿瘤细胞nm23 mRNA表达水平。结果 8株卵巢恶性肿瘤细胞中4株有较高转移潜能。多次培养接种可筛选出高频转移细胞亚群。测定各类细胞nm23 mRNA表达水平与肿瘤转移特性呈负相关。结论 由基因分子水平决定的肿瘤转移趋势在不同肿瘤种类及细胞亚群中有明显差异;卵巢癌中nm23 mRNA和蛋白的表达与其转移能力的降低有密切关系,可作为判定卵巢癌预后的敏感指标。 相似文献
993.
目的 为研究与人前列腺癌细胞(PC-3M)侵袭能力相关的靶分子。方法 采用有限稀释法分离单克隆细胞株,并应用单层细胞侵袭等实验鉴定各亚系的体外侵袭能力;借助RT-PCR和免疫组化的方法,分别在转录和翻译水平检测5株侵袭能力不同的PC-3M亚系尿激酶型纤溶酶原激活物受体(u-PAR)的表达。结果 高侵袭亚系u-PAR基因mRNA的表达和蛋白质水平均明显高于低侵袭亚系。结论 PC-3M亚系u-PAR的高表达与其较强的侵袭能力密切相关,而u-PAR可能是抑制高侵袭亚系侵袭效应的一个重要靶分子。 相似文献
994.
Clinical evaluation of the simultaneous determination of tumor markers in fluid and serum and their ratio in the differential diagnosis of serous effusions. 总被引:13,自引:0,他引:13
We evaluated the diagnostic utility of simultaneous determination of 5 tumor markers, CEA, CA 125, CA 15-3, CA 19-9 and cytokeratin 19 (CYFRA 21-1), in fluid and serum from 101 patients, 52 with pleural effusion (22 malignant) and 49 patients with ascites (14 malignant). Tumor marker concentrations in fluid from patients with malignant effusions were significantly higher than those obtained in benign fluids or serum. However, there are two types of tumor markers: those released/secreted by normal mesothelia such as CA 125 and cytokeratin 19 (higher levels in benign fluids than in serum) and non-released/secreted tumor markers (low concentrations in benign fluids) such as CEA, CA 19-9 and CA 15-3. The fluid/serum (F/S) ratio showed better sensitivity with maximum specificity than a single determination in fluid for CEA, CA 15-3 and CA 19-9, but not for CA 125 and CYFRA. The combination of a F/S ratio greater than 1.2 and a cut-off of 5 ng/ml for CEA, 30 U/ml for CA 15-3 and 37 U/ml for CA 19-9 showed sensitivities of 58, 57 and 44%, respectively, and a specificity of 100%, with a combined sensitivity of 82% for overall effusions and 79% for fluids with negative cytology with a specificity of 100%. In conclusion, the use of the F/S ratio in nonsecreted tumor markers such as CEA, CA 19-9 and CA 15-3 improve the sensitivity and specificity and allow standardization of the cut-off. 相似文献
995.
Vicente Valentín Maganto Maite Murillo González María Valentín Moreno 《Clinical & translational oncology》2004,6(7):448-457
Continuous care for the cancer patient is an open concept that is not only applicable only to the terminal stage. Such a simplification
could generate inequities of therapy and discrimination. Historically, oncology services have been structured as networks
dispensing chemotherapy and radiotherapy rather than services dedicated to the integrated care of the cancer patient. This
situation has changed in a continuous and progressive manner over the past few years, as reflected in the latest Spanish Libro
Blanco de Oncología. We are still far from reaching the optimum level of integrated care, possibly because we have not, as
yet, achieved services that are structured and appropriate for the care-needs of the patient and, perhaps, to the lack of
the necessary personnel. We must always make sure that cancer patients receive the best possible treatment, irrespective of
whet-her the disease is in relapse. Oncologists must not “give up”, indicating that, in addition to using the most effective
anticancer treatments available, they should deploy their best knowledge and experience to control the symptoms of cancer
while providing psycho-social help to the patient and family. This is best conducted with a communication that is adjusted
to the changing needs of the patient over the longterm clinical process, and should be provided by a multidisciplinary team,
according to the needs of the patient and the family.
Within a program of integrated care, it is possible to coordinate the existing care structures without creating parallel health
networks so as to cover the needs of the greatest number of cancer patients in advanced stage of the disease. 相似文献
996.
Pseudomixoma peritoneal tipo adenomucinosis peritoneal diseminada con imágenes radiológicas atípicas
Manuel Vallalta Morales Ángel Segura Huerta Carmen Gil Adiego Laura Palomar Abad Jorge Molina Saera Roberto Díaz Beveridge 《Clinical & translational oncology》2004,6(3):173-175
Pseudomyxoma peritonei is an unusual condition that has caused much confusion regarding its aetiology, clinical manifestations, treatment and prognosis. It is characterised by mucinous ascites and diffuse mucinous invasions of the peritoneum. Three histological subtypes have been defined: a) disseminated peritoneal adenomucinosis (peritoneal lesions composed of abundant extra-cellular mucin containing scant simple-to-focally-proliferating mucinous epithelium with little cytological atypia or mitotic activity); b) peritoneal mucinous carcinomatosis (peritoneal lesions composed of more abundant mucinous epithelium with the architectural and cytological features of carcinoma); and c) an intermediate group. The different histological subtypes have different prognoses. We report a case of disseminated peritoneal adenomatosis, and discuss its clinical management. 相似文献
997.
Beata Gawdis-Wojnarska Marek Brzosko Jacek Fliciński Krzysztof Marlicz Teresa Starzyńska Rodney J Scott Jan Lubiński 《Hereditary cancer in clinical practice》2004,2(2):65-68
Gastric cancer is the second most frequently diagnosed malignancy worldwide and therefore represents a significant healthcare burden. Environmental and genetic factors are involved in the development of gastric cancer. To date only one clear genetic predisposition has been identified involving mutations in the E-cadherin gene. The disease phenotype in patients harbouring E-cadherin mutations appears to be specifically related to diffuse gastric cancer. Little is known genetically about the other forms of gastric cancer. Since there is a growing awareness about the necessity of early intervention criteria have been developed that aid the identification of hereditary forms of gastric cancer. The aim of the current study was to identify minimal inclusion criteria so that nuclear pedigree families can be provided with risk assessment and/or genetic testing.The results reveal that inclusion features described herein such as (a) gastric cancer diagnosed before 46 years of age; (b) two gastric cancers among first degree relatives diagnosed over the age of 50 are useful in identifying suspected hereditary gastric cancer patients. 相似文献
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