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101.
PURPOSE: C-Jun NH(2)-terminal kinase (JNK) has been implicated in numerous functions including stress responses, apoptosis,and transformation. The role in transformation is based largely on studies of isolated cell types with little indication of whether JNK plays a general role in a specific human tumor type or whether this occurs in vivo. EXPERIMENTAL DESIGN: We examined 9 human prostate carcinoma cell lines in vitro and a representative line in vivo. RESULTS: For all of the cell lines proliferation is highly correlated with serum-supported JNK activity (r(Pearson) = 0.91; P = 0.004), whereas no relationship was observed for 10 human breast cancer cell lines (r(Pearson) = -0.32). Treatment with characterized antisense oligonucleotides complementary to sequences common to either the JNK1 or JNK2 family of isoforms showed that, whereas antisense JNK1 inhibited growth by a maximum of 57%, antisense JNK2 inhibited proliferation up to 80%. Sense and scrambled control oligonucleotides had little effect (average 3.7 +/- 1.5%). Moreover, systemic treatment of mice bearing established xenografts of PC3 prostate carcinoma cells with antisense JNK1 and JNK2 led to inhibition tumor growth by 57% (P < 0.002) and 80% (P < 0.001), respectively. The difference is significant (P < 0.012). Combined antisense treatment led to a significant increase in frequency of tumor regression (P = 0.022). CONCLUSION: These results indicate that JNK is required for growth of prostate carcinoma cells in vitro and in vivo, and additionally indicate that JNK2 plays a dominant role. The JNK pathway is a novel target in the treatment of prostate carcinoma.  相似文献   
102.
The Human Genome Project will have an enormous impact on our ability to study and understand human disease by providing maps of human genes. However, many of the most prevalent human diseases result from the complex interaction of numerous genes. Even with the use of a catalogue of human genes, the task of analyzing complex genetic and environmental interactions involved in the common human disorders will be formidable. Due to its demographic specificities and large size, the Chinese population offers a unique resource for the study of human genetics and the ability to capitalize upon the recent revolution in biotechnology. Reasons that China provides an exceptional population for genetic studies of complex diseases include: (i) the resource of 1.3 billion people makes obtaining a large number of subjects with rare (and common) diseases possible; (ii) relative genetic homogeneity in many regions has been preserved; (iii) stratification is distinct; (iv) urban/rural and geograph ic contrasts, both in environmental factors and disease occurrence, are quite marked; (v) family members tend to stay congregated; and (vi) epidemiologic study is cost-beneficial.  相似文献   
103.
Endometrial carcinomas are classified by their morphology into two major subtypes. Endometrioid carcinomas (type I) are generally estrogen dependent, well-differentiated, superficially invasive, and have a good outcome. Serous carcinomas (type II) are hormone independent, frequently deeply invasive and widely metastatic, and have a poor prognosis. Microarray technology and analysis allows us to determine if the global gene expression profiles of these two subtypes correlate with their morphologic phenotype. Fresh tissue from 18 endometrial carcinomas was studied: 7 well-, 2 moderately, and one poorly differentiated endometrioid, 4 serous carcinomas, and 4 high-grade mixed endometrioid-serous carcinomas. Labeled cDNA probes were synthesized (Cy5 for tumor, Cy3 for reference) and applied to microarrays containing 18,098 cDNA clones or ESTs. A pool of equal amounts of total RNA from each tumor served as the reference RNA. By unsupervised cluster analysis, the endometrioid carcinomas clustered together and were separate from the serous carcinomas. The high-grade mixed carcinomas clustered with the serous carcinomas. Using a statistical algorithm based on gene expression pattern and conducting a supervised analysis of the two defined groups, we have identified 315 genes that statistically differentiate type I from type II endometrial carcinomas. In addition to corroborating the predicted overexpression of known markers (e.g., ras and catenin in endometrioid carcinomas), the cDNA microarray technique has revealed novel alterations in gene expression relevant to cell cycle, cell adhesion, signal transduction, apoptosis, and tumor progression not previously implicated in endometrial carcinomas. For serous carcinomas, these include aldolase, desmoplakin, integrin-linked kinase, PKC, and metallopeptidase. In conclusion, the gene expression profiles of type I and type II endometrial carcinomas are different. Refinement of these profiles will permit more accurate diagnostic tumor classification and the development of prognosis assays.  相似文献   
104.
105.
PURPOSE: To determine the incidence of second malignancies among patients with Hodgkin's lymphoma (HL) treated with autologous hematopoietic stem cell transplantation (AHSCT) compared with patients receiving conventional therapy alone and to identify potential risk factors for their occurrence. PATIENTS AND METHODS: We analyzed data on 1,732 consecutive patients with HL treated at the British Columbia Cancer Agency from 1976 to 2001, including 202 patients undergoing AHSCT. The median follow-up duration was 9.8 years for the whole cohort, 9.7 years for those patients treated with conventional therapy, and 7.8 years from AHSCT. RESULTS: The cumulative incidence of developing any second malignancy 15 years after therapy for HL was 9% (risk ratio = 3.5; P < .001); however, the incidence did not differ between those patients receiving conventional therapy alone compared with those undergoing AHSCT (10% and 8%, respectively; P = .48). In multivariate analysis, the only factor significantly associated with an increased risk of developing any second neoplasm or solid tumor was age > or = 35 years (P < .0001). An increased risk of therapy-induced acute myeloid leukemia and therapy-induced myelodysplastic syndrome was seen for patients aged > or = 35 years (P = .03) and stage III/IV (P = .04). CONCLUSION: Patients with HL are at increased risk of developing a second neoplasm. However, those patients undergoing AHSCT do not seem to be at greater risk compared with those patients receiving conventional therapy alone, at least during the first decade after therapy.  相似文献   
106.
PURPOSE: Ifosfamide, carboplatin, etoposide, and vincristine, alone and in combination, are highly active against small-cell lung cancer (SCLC). This trial was designed to investigate whether survival could be improved by a regimen of all four drugs (ICE-V) compared with standard chemotherapy in patients with SCLC and good performance status, and to assess the patients' quality of life (QL). PATIENTS AND METHODS: Patients were randomly assigned to receive six cycles of either ICE-V at 4-week intervals without dose reduction or standard chemotherapy administered according to local practice. The recommended standard control regimens were cyclophosphamide, doxorubicin, and etoposide; and cisplatin and etoposide. RESULTS: A total of 402 patients were randomly assigned, and 350 (87%) patients have died. Overall survival was longer in the ICE-V group (hazard ratio, 0.74; 95% CI, 0.60 to 0.91; P = .0049), median survival was 15.6 months in the ICE-V group and 11.6 months in the control group, and 2-year survival rates were 20% and 11%, respectively. There was no evidence that the relative survival benefit for ICE-V was less in extensive-stage than in limited-stage patients. An increased rate of septicemia was reported in the ICE-V group (15% v 7% in the control group), but this did not result in an increase in reported treatment-related deaths (four patients [2%] in both groups). The findings on QL were broadly similar in both groups, with some benefit in favor of ICE-V. CONCLUSION: Compared with standard chemotherapy, the ICE-V regimen improves overall survival without QL penalties, despite an increased but manageable level of toxicity.  相似文献   
107.
Imexon is an aziridine-containing small molecule currently in Phase I clinical trials. This agent has been shown to bind to thiols and increase intracellular oxidants, inducing apoptosis in hematologic cancer cells. Pancreatic cancers are known to be sensitive to oxidation, suggesting this disease may be an appropriate target for this agent. The current report examines the activity of imexon in pancreatic cells. Imexon induced concentration-dependent and time-dependent apoptosis in a panel of six human pancreatic carcinoma cell (PCC) lines. The mean IC50 (SD) for growth inhibition by the SRB assay was 200 (101) µM for a 48 h exposure with a range of 64–358 µM. Cell killing was schedule-dependent, favoring exposure times ≥48 h. Imexon-treated MiaPaCa-2 cells underwent non-lethal growth arrest following exposure to concentrations ≤200 µM for 48 h. When concentrations were increased to 300 µM for ≥48 h, the MiaPaCa-2 cells arrested in G2 phase and activated caspases 3, 8, and 9 were detected. After a 72 h exposure to the IC80 concentration of imexon, cells exhibited a loss of mitochondrial membrane potential detected by CMXRos staining. However, there was no loss of reduced cellular thiols unless very high concentrations of ≥400 µM were used. In contrast, reactive oxygen species (ROS) were elevated in a dose-dependent fashion, starting at very low imexon concentrations. Imexon also significantly inhibited MiaPaCa-2 tumor growth in SCID mice at 100 mg/kg/d for 9 d. The tumor growth inhibition (% T/C) was 27% of control, and the tumor growth delay was 21 d, indicating an active agent by NCI standards. The levels of imexon that are cytotoxic in human PCC’s are achievable based on the preliminary results of the ongoing Phase I trial. Imexon appears to be active against PCCs in vitro and has an entirely novel mechanism of action involving G2 arrest, accumulation of ROS, and the induction of apoptosis.  相似文献   
108.
Chronic heart failure (CHF) is a major cause of morbidity and mortality in western society. It is now widely accepted that the renin-angiotensin-aldosterone system (RAAS) and, in particular, angiotensin II (A-II) play a key role in the pathophysiology of CHF. Large-scale clinical trials have demonstrated that inhibitors of angiotensin-converting enzyme (ACE), the principal enzyme responsible for A-II production, improve symptoms and survival in patients with CHF. This enzyme is also responsible for the breakdown of the vasodilator hormone bradykinin. Administration of ACE inhibitors is associated with increased plasma bradykinin levels and this is thought to contribute to the vascular changes associated with ACE inhibitor therapy. However, RAAS inhibition with ACE inhibitors remains incomplete because ACE inhibitors do not block the non-ACE-mediated conversion of angiotensin I to A-II. Angiotensin receptor antagonists (angiotensin receptor blockers; ARBs) antagonize the action of A-II at the A-II type 1 (AT(1)) receptor, whilst allowing the potentially beneficial actions of A-II mediated via the A-II type 2 (AT(2)) receptor. Evidence that the clinical benefit demonstrated with ACE inhibitors in patients with CHF may extend to ARBs has only emerged recently. Combination therapy with both an ACE inhibitor and an ARB has a number of potential advantages and has been investigated in several large-scale clinical trials recently. In patients with CHF, first-line therapy should include an ACE inhibitor and a beta-adrenoceptor antagonist. The addition of an ARB provides symptomatic relief but has not been shown to improve survival. Where an ACE inhibitor is not tolerated, treatment with an ARB would seem an appropriate alternative. There is insufficient data to support the routine use of ARBs as first-line therapy in the management of CHF.  相似文献   
109.
110.
BackgroundPrevious research has demonstrated the benefits of both stabilization and non-stabilization of the scapula during stretching in individuals with posterior shoulder tightness, but limited evidence exists in patients with shoulder pain.Hypothesis/PurposeThe aim of this study was to determine the effect of stabilized scapular stretching on patients with shoulder pain. The primary hypothesis of this study is that stabilized scapular stretching will improve glenohumeral motion and pain compared to non-stabilized stretch program. A secondary hypothesis of this study is that stabilized scapular stretching will produce greater improvement in function compared to the non-stabilized stretching program.Study DesignRandomized Clinical TrialMethodsSixteen patients with sub-acromial pain associated with tendinopathy and associated pathologies presenting to physical therapy were randomized into two groups (stabilized or non-stabilized scapular stretching). Baseline pain and range of motion were measured prior to and following each treatment session for three visits that occurred over the course five to seventeen days depending on the patients availability. The dependent measurements were stabilized horizontal adduction, stabilized internal rotation, stabilized shoulder flexion, non-stabilized shoulder flexion, and current pain level.ResultsPatients in the scapular stabilization stretching group increased horizontal adduction 40° (CI95 31, 48°) compared to the non-stabilization stretching group increase of 8° (CI95 0, 17°) over the course of the three treatments (p<0.001). Similarly, the stabilized stretching group increased internal rotation 48° (CI95 26, 69°) compared to the non-stabilized stretching group increase of 26° (CI95 4, 48°) (p=0.001). Pain decreased in the stabilized stretching group by 1.4 points (CI95 -0.4, 3.2) but increased slightly in non-stabilized group by -0.5 points (CI95 -2.3, 1.3) which was not a clinically meaningful change. (p=0.03)ConclusionStabilized scapular stretching was more effective than non-stabilized stretching at gaining shoulder mobility in patients with shoulder pain. Benefits were immediate and sustained between treatment sessions. Stretching interventions improved range of motion but had limited effect on shoulder pain.Level of Evidence2  相似文献   
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