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21.
BACKGROUND: Hypermethylation is studied as a new, relevant mechanism for silencing tumor suppressor genes. It is a potentially reversible epigenetic change and it is the target of novel anticancer compounds with demethylating activity. In this perspective, we investigated E-cadherin gene (CDH1) promoter hypermethylation in gastric carcinomas and its correlation with E-cadherin protein expression. METHODS: Consecutive cases of gastric carcinoma with assessable paraffin-embedded tumor blocks and paired normal mucosa were considered eligible for study entry. CDH1 promoter hypermethylation and E-cadherin protein expression were determined by methylation-specific polymerase chain reaction and immunohistochemistry, respectively. RESULTS: CDH1 promoter hypermethylation was found in 20 out of 70 gastric carcinomas and the epigenetic change occurred in the early, as well as in the locally advanced disease. In five cases, hypermethylation was also detected in the normal mucosa. Eighteen out of 20 hypermethylated tumors were of the diffuse histotype (P=0.0001). Of 24 tumors with reduced or negative E-cadherin expression, 19 were hypermethylated and 5 were unmethylated (P=0.0001). CONCLUSIONS: CDH1 promoter hypermethylation frequently occurs in gastric carcinomas of the diffuse histotype and it is significantly associated with downregulated E-cadherin expression. The knowledge on the hypermethylation status of tumor suppressor genes may be relevant to the development of demethylating drugs and novel chemopreventive strategies in solid tumors.  相似文献   
22.
The benefit of postoperative adjuvant chemotherapy in patients with Dukes' B colorectal cancer is still uncertain and its routine use is not recommended. Prognostic biomarkers may be useful for identifying high-risk patients with resected, node-negative disease, and this stratification may represent an innovative strategy for designing adjuvant chemotherapy trials. Featured prognostic molecular markers can be divided into the following categories: cell proliferation indices (Ki-67, Mib-1, proliferating cell nuclear antigen); oncogenes/tumor suppressor genes [p53, K-ras, Deleted in Colorectal Cancer (DCC), Bcl-2, c-erbB2]; DNA repair (microsatellite instability); markers of angiogenesis (vascular count, vascular endothelial growth factor); markers of invasion/metastasis (plasminogen-related molecules, matrix metalloproteinases); and biochemical markers (thymidylate synthase). Studies that have investigated their prognostic role in Dukes' B colorectal cancer patients are reviewed here. Current data do not provide sufficient evidence for the incorporation of available prognostic biomarkers into clinical practice. However, a biomarker-based approach could be an effective strategy for improving results of postoperative adjuvant treatments in high-risk Dukes' B colorectal cancer patients. Markers of altered DCC function have shown promising prognostic role and sufficient prevalence in retrospective investigations and they deserve further assessment in prospective studies.  相似文献   
23.
OBJECTIVE: To determine the relationship between p53 overexpression and vascular endothelial growth factor (VEGF) upregulation in liver and abdominal metastases from colon cancer. The analysis in the two metastatic sites was carried out to evaluate the potential role of microenvironment in the molecular regulation of VEGF. METHODS: Bioptic specimens of liver and abdominal metastases from colon carcinomas were examined by immunohistochemistry for p53 and VEGF expressions. Consecutive cases with assessable tumor tissue were selected. RESULTS: The study population consisted of 24 cases having liver metastases and 34 cases having abdominal metastases. Abdominal metastases showed a higher number of VEGF-positive cases and a higher intensity of VEGF immunoreactivity than liver metastases did (p = 0.01). The combined analysis of p53 and VEGF showed a strong association between the two markers in the 24 liver metastases; 9 cases were VEGF positive/p53 positive and 15 cases were VEGF negative/p53 negative. This relationship was not found in the 34 abdominal metastases, which showed concordance between the two markers in 9 VEGF-positive/p53-positive cases only. CONCLUSIONS: Microenvironment factors like hypoxia may have a predominant role in inducing VEGF expression and they can override the molecular control of p53 on VEGF.  相似文献   
24.
BACKGROUND: In gastric juice, high levels of the carcinoembryonic antigen (CEA) and the carbohydrate antigen 19-9 (CA 19-9) have been found to correlate with precancerous lesions and gastric cancer. So far, sampling of gastric juice has required upper endoscopy. In place of this invasive procedure, we investigated a new tool for the quantitation of tumor markers in gastric juice. MATERIALS AND METHODS: The study population consisted of healthy controls and consecutive subjects with suspected gastric cancer or dyspepsia/epigastric distress. Patients were asked to swallow a small gelatine capsule (14 mm in length and 5 mm in diameter) containing a pierced plastic cover and surrounding a piece of absorbent paper. The capsule was left in the gastric cavity for 60 min to allow saturation of the absorbent paper with gastric juice. A 45-50 cm length of nylon thread connected to the inner capsule was used to remove the device from the gastric cavity. After processing the absorbent paper for radioimmunoassay, CEA and CA 19-9 levels were correlated to the findings of upper endoscopy and biopsies of gastric mucosa or suspected lesions. RESULTS: The endogastric capsule did not cause any side-effects and 62 participants were fully compliant to the procedure. Assessable gastric juice samples were taken from 23 patients with gastric cancer, 15 patients with intestinal metaplasia or dysplasia, 12 patients with gastritis and 12 controls without gastric diseases. In the 12 samples of gastric juice from control patients, mean values of CEA and CA 19-9 were 1.1 +/- 0.9 ng/ml and 16 +/- 7.5 ng/ml, respectively. The mean levels of both markers were found to increase according to the severity of gastric lesions and in patients with cancer, mean CEA and CA 19-9 levels were 513 +/- 627 ng/ml and 545 +/- 510 ng/ml, respectively. Patients with precancerous lesions and cancer showed higher levels of CEA and CA 19-9 than patients with normal findings or gastritis (P <0.001). CONCLUSIONS: The endogastric capsule is a simple, non-invasive tool for the measurement of CEA and CA 19-9 levels in gastric juice. These values may discriminate between normal or minor pathologic changes and precancerous lesions or carcinomas. Further investigations are warranted, since this may represent a new method for gastric cancer screening.  相似文献   
25.
PURPOSE: We compared the efficacy of combination chemotherapy versus single-agent therapy in patients with advanced non-small-cell lung cancer. PATIENTS AND METHODS: A total of 561 eligible patients were randomly assigned to receive paclitaxel alone or in combination with carboplatin. RESULTS: The response rate was 17% in the paclitaxel arm and 30% in the carboplatin-paclitaxel arm (P < .0001). Median failure-free survival was 2.5 months in the paclitaxel arm and 4.6 months in the carboplatin-paclitaxel arm (P = .0002). Median survival times were 6.7 months (95% CI, 5.8 to 7.8) and 8.8 months (95% CI, 8.0 to 9.9), and 1-year survival rates were 32% (95% CI, 27% to 38%), and 37% (95% CI, 32% to 43%), respectively. The overall survival distributions were not statistically different: hazard ratio = 0.91 (95% CI, 0.77 to 1.17; P = .25). Hematological toxicity and nausea were more frequent in the combination arm, but febrile neutropenia and toxic deaths were equally low in both arms. There was no significant survival difference in elderly patients. Performance status 2 patients treated with combination chemotherapy had a better survival rate than those treated with single-agent therapy (P = .019). CONCLUSION: Combination chemotherapy improves response rate and failure-free survival compared with single-agent therapy, but there was no statistically significant difference in the primary end point of overall survival. The results in elderly patients were similar to younger patients. Performance status 2 patients had a superior outcome when treated with combination chemotherapy.  相似文献   
26.
2,3-Dimercaptosuccinic acid (DMSA) is an orally effective orphan drug that is more specific and has a wider therapeutic index than other currently available drugs used for lead intoxication. Its investigational use in the United States has been limited to the treatment of men with occupational plumbism. Twenty-one children with blood lead concentrations of 31 to 49 micrograms/dl, who also had a positive calcium disodium edetate (CaNa2EDTA) mobilization test result, were hospitalized for 7 days. Fifteen children were randomly assigned to three groups that received either 350, 700, or 1050 mg/m2/day, respectively, of DMSA in three divided doses daily. A fourth group of six children received conventional treatment with 1000 mg/m2/day of intravenously administered CaNa2EDTA in two divided doses daily. The 1050 mg/m2/day dose of DMSA was significantly more effective than lower doses of DMSA or intravenously administered CaNa2EDTA in reducing blood lead levels and restoring erythrocyte delta-aminolevulinic acid dehydratase activity. Intravenously administered CaNa2EDTA significantly increased the urinary excretion of several essential minerals (zinc, copper, iron, and calcium), whereas DMSA did not. The DMSA was well tolerated and appears extremely promising as a drug that will simplify the management of childhood lead poisoning.  相似文献   
27.
OBJECTIVE: To determine the rate of medical record documentation of urinary incontinence (UI) symptoms during the third trimester of pregnancy and postpartum period. STUDY DESIGN: Third-trimester prenatal patients were invited to participate in an institutional board-approved prospective study. Participants completed the 15-item, validated Medical, Epidemiological and Social Aspects of Aging (MESA) questionnaire. The MESA was readministered to participants during a 6-8-week postpartum visit. Outpatient and inpatient medical records were reviewed to determine whether UI symptoms were documented. RESULTS: One hundred sixty women had antenatal MESA and 90 had postpartum MESAs. Of the 160 women with antenatal MESAs, 118 were symptomatic (73%). Five medical records (3.1%) reflected any assessment of UI. Postpartum, 43% of women were incontinent by MESA. Documentation of incontinence assessment was present in 21% of medical records. CONCLUSION: Medical record documentation of UI symptom screening throughout pregnancy and postpartum rarely occurred in this study population.  相似文献   
28.
Androgen deficiency in older men   总被引:1,自引:0,他引:1  
Androgen deficiency in older men can be related to age associated changes of neuro-endocrine mechanisms controlling the hormones secreted by the testis and adrenal cortex. We listed the clinical consequences of androgen deficiency at three different levels in three areas: somatic (body composition, glucidic and lipid metabolism, erythropoiesis), sexual and psychological (cognition and affectivity). Observational studies and randomized placebo controlled trials have been reviewed from medical literature. Testosterone, now preferentially administered as transdermal gel, and dehydroepiandrosterone represent two possible treatments. New compounds designed to target androgen receptors in specific tissues are promising options as anabolic agents.  相似文献   
29.
Management of cervicocarcinoma during pregnancy is influenced by gestational age, stage of disease, and patient's desire to maintain her pregnancy. We report a case of a pregnant patient with locally advanced cervicocarcinoma successfully treated by neoadjuvant chemotherapy, followed by caesarean section and radical surgery.  相似文献   
30.

Objectives

In Parkinson disease (PD), sarcopenia may represent the common downstream pathway that from motor and nonmotor symptoms leads to the progressive loss of resilience, frailty, and disability. Here we (1) assessed the prevalence of sarcopenia in older adults with PD using 3 different criteria, testing their agreement, and (2) evaluated the association between PD severity and sarcopenia.

Design

Cross-sectional, observation study.

Setting

Geriatric day hospital.

Participants

Older adults with idiopathic PD.

Measurements

Body composition was evaluated through dual energy x-ray absorptiometry. Handgrip strength and walking speed were measured. Sarcopenia was operationalized according to the Foundation for the National Institutes of Health, the European Working Group on Sarcopenia in Older Persons, and the International Working Group. Cohen k statistics was used to test the agreement among criteria.

Results

Among the 210 participants (mean age 73 years; 38% women), the prevalence of sarcopenia was 28.5%–40.7% in men and 17.5%–32.5% in women. The prevalence of severe sarcopenia was 16.8%–20.0% in men and 11.3%–18.8% in women. The agreement among criteria was poor. The highest agreement was obtained between the European Working Group on Sarcopenia in Older Persons (severe sarcopenia) and International Working Group criteria (k = 0.52 in men; k = 0.65 in women; P < .01 for both). Finally, severe sarcopenia was associated with PD severity (odds ratio 2.30; 95% confidence interval 1.15–4.58).

Conclusions

Sarcopenia is common in PD, with severe sarcopenia being diagnosed in 1 in every 5 patients with PD. We found a significant disagreement among the 3 criteria evaluated, in detecting sarcopenia more than in ruling it out. Finally, sarcopenia is associated with PD severity. Considering its massive prevalence, further studies should address the prognosis of sarcopenia in PD.  相似文献   
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