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3621. DNA markers predicting benefit from adjuvant fluorouracil in patients with colon cancer: a molecular study.

作者: P L Barratt.;M T Seymour.;S P Stenning.;I Georgiades.;C Walker.;K Birbeck.;P Quirke.; .
来源: Lancet. 2002年360卷9343期1381-91页
Present clinical algorithms assign adjuvant chemotherapy according to prognosis, but clinical decision-making would be greatly improved if reliable predictive markers were available to identify which subsets of patients benefit most from treatment. We examined molecular markers in preserved tissue from patients with Dukes' B or C colon cancer randomised to receive, or not, adjuvant fluorouracil, and assessed each marker's prognostic and predictive value.

3622. Effects of risk counseling on interest in breast cancer genetic testing for lower risk women.

作者: Deborah J Bowen.;Wylie Burke.;Yutaka Yasui.;Anne McTiernan.;Dale McLeran.
来源: Genet Med. 2002年4卷5期359-65页
A randomized trial was conducted to test the effects of two counseling methods (genetic counseling and group counseling) against a control no-intervention condition on interest in genetic testing in lower risk women.

3623. Associations between carcinogen-DNA damage, glutathione S-transferase genotypes, and risk of lung cancer in the prospective Physicians' Health Cohort Study.

作者: Frederica P Perera.;LaVerne A Mooney.;Meir Stampfer.;David H Phillips.;Douglas A Bell.;Andrew Rundle.;Stan Cho.;Wei-Yann Tsai.;Jing Ma.;Anne Blackwood.;Deliang Tang.; .
来源: Carcinogenesis. 2002年23卷10期1641-6页
DNA damage from polycyclic aromatic hydrocarbons (PAH) and other aromatic/hydrophobic compounds has been implicated in case-control studies as a risk factor for lung cancer, as have common polymorphisms in the glutathione S-transferase (GST) genes involved in carcinogen detoxification. However, their joint effects have not been evaluated in prospective studies, leaving open questions about predictive value of these biomarkers. In this matched case-control study nested within the prospective Physicians' Health Study, we evaluated whether biomarkers measured in white blood cells (WBC) significantly predicted risk, alone and in combination, after controlling for level of smoking. The biomarkers reported here are aromatic/hydrophobic-DNA adducts and polymorphisms in genes coding for the GSTM1 and GSTP1 enzymes. Our study population was composed of 89 cases of primary lung cancer and 173 controls, matched in a 1:2 ratio on smoking, age and duration of follow up. Adducts were measured in WBC DNA by the nuclease P1-enhanced (32)P-post-labeling method. Genotypes (GSTM1 null versus non-null and GSTP1 Val versus GSTP1 Ile) were determined by genomic amplification and restriction fragment length polymorphism analysis. Among current smokers, adducts were significant predictors of lung cancer risk (after adjusting for GST genotypes, OR = 3.10, 95% CI 1.07, 9.01). The combined GSTM1 null/GSTP1 Val genotype was associated with lung cancer overall and especially among former smokers, before and after adjusting for adducts (OR for former smokers = 4.21, CI 1.08, 16.41; adjusted OR = 4.68, CI 1.17, 18.71). Among cases only, adducts were significantly higher among current or former smokers with the GSTM1 non-null/GSTP1 Ile genotype. The two risk factors (adducts and genotypes) appear to be independent predictors of risk. The findings underscore the complex and important role of biological susceptibility as a determinant of risk from carcinogens found in tobacco smoke and other environmental compounds.

3624. First results from the International Breast Cancer Intervention Study (IBIS-I): a randomised prevention trial.

作者: J Cuzick.;J Forbes.;R Edwards.;M Baum.;S Cawthorn.;A Coates.;A Hamed.;A Howell.;T Powles.; .
来源: Lancet. 2002年360卷9336期817-24页
Three clinical trials on the use of tamoxifen to prevent breast cancer have reported mixed results. The overall evidence supports a reduction in the risk of breast cancer, but whether this benefit outweighs the risks and side-effects associated with tamoxifen is unclear.

3625. Dietary antioxidants and DNA damage in patients on long-term acid-suppression therapy: a randomized controlled study.

作者: K L M White.;D M Chalmers.;I G Martin.;S M Everett.;P M Neville.;G Naylor.;A E Sutcliffe.;M F Dixon.;P C Turner.;C J Schorah.
来源: Br J Nutr. 2002年88卷3期265-71页
Free radicals and reactive species produced in vivo can trigger cell damage and DNA modifications resulting in carcinogenesis. Dietary antioxidants trap these species limiting their damage. The present study evaluated the role of vitamins C and E in the prevention of potentially premalignant modifications to DNA in the human stomach by supplementing patients who, because of hypochlorhydria and possible depletion of gastric antioxidants, could be at increased risk of gastric cancer. Patients undergoing surveillance for Barrett's oesophagus (n 100), on long-term proton pump inhibitors were randomized into two groups: vitamin C (500 mg twice/d) and vitamin E (100 mg twice/d) for 12 weeks (the supplemented group) or placebo. Those attending for subsequent endoscopy had gastric juice, plasma and mucosal measurements of vitamin levels and markers of DNA damage. Seventy-two patients completed the study. Plasma ascorbic acid, total vitamin C and vitamin E were elevated in the supplemented group consistent with compliance. Gastric juice ascorbic acid and total vitamin C levels were raised significantly in the supplemented group (P=0.01) but supplementation had no effect on the mucosal level of this vitamin. However, gastric juice ascorbic acid and total vitamin C were within normal ranges in the unsupplemented group. Mucosal malondialdehyde, chemiluminescence and DNA damage levels in the comet assay were unaffected by vitamin supplementation. In conclusion, supplementation does not affect DNA damage in this group of patients. This is probably because long-term inhibition of the gastric proton pump alone does not affect gastric juice ascorbate and therefore does not increase the theoretical risk of gastric cancer because of antioxidant depletion.

3626. The use of audiotapes in consultations with women from high risk breast cancer families: a randomised trial.

作者: E Lobb.;P Butow.;B Meiser.;A Barratt.;J Kirk.;M Gattas.;E Haan.;K Tucker.
来源: J Med Genet. 2002年39卷9期697-703页

3627. Prognostic significance of FLT3 internal tandem repeat in patients with de novo acute myeloid leukemia treated with reinforced courses of chemotherapy.

作者: N Boissel.;J M Cayuela.;C Preudhomme.;X Thomas.;N Grardel.;X Fund.;I Tigaud.;E Raffoux.;P Rousselot.;F Sigaux.;L Degos.;S Castaigne.;P Fenaux.;H Dombret.
来源: Leukemia. 2002年16卷9期1699-704页
FLT3 internal tandem duplications (FLT3-ITDs) are present in nearly 25% of patients with AML and have been associated with poor response to conventional therapy and poor outcome. We retrospectively evaluated the effect of reinforced courses of chemotherapy on the prognostic value of FLT3-ITDs in 159 AML patients prospectively enrolled in the ALFA-9000 trial, which randomly compared three reinforced induction regimens (standard 3+7 including high-dose daunorubicin, double induction, and timed-sequential therapy). FLT3-ITD was present in 40/159 (25%) blast samples and associated with high WBC (P = 0.002) and cytogenetics (P < 0.001) with a higher incidence (35%) in patients with a normal karyotype. There was no difference in CR rate between FLT3-wt and FLT3-ITD patients (80% vs 78%). Relapse-free survival (RFS) was similar in both groups (5-year RFS, 33% vs 32%; P = 0.41), even after adjustment for age, sex, WBC, cytogenetics, and treatment arm. A trend to a worse survival was observed in the FLT3-ITD group (estimated 5-year OS, 23% vs 37%; P = 0.09), mainly in patients with a normal karyotype. This was associated with a dramatic outcome in relapsing FLT3-ITD patients (estimated 3-year post-relapse survival, 0% vs 27%; P = 0.04). These results suggest that the bad prognosis associated with FLT3-ITDs in AML might be partly overcome using reinforced chemotherapy. Early detection of FLT3 mutations might thus be useful to intensify induction as well as post-remission therapy in FLT3-ITD patients.

3628. Tailoring communication in consultations with women from high risk breast cancer families.

作者: E A Lobb.;P N Butow.;B Meiser.;A Barratt.;C Gaff.;M A Young.;J Kirk.;G K Suthers.;K Tucker.
来源: Br J Cancer. 2002年87卷5期502-8页
This multicentre study examined the influence of patient demographic, disease status and psychological variables on clinical geneticists/genetic counsellors (consultants) behaviours in initial consultations with women from high-risk breast cancer families. One hundred and fifty-eight women completed a pre-clinic self-report questionnaire. The consultations were audiotaped, transcribed verbatim and coded. Consultants did not vary their behaviour according to women's expectations. However, significantly more aspects of genetic testing were discussed with women who were affected with breast cancer (P<0.001), screening and management with unaffected women (P=0.01) and breast cancer prevention with younger women (P=0.01). Prophylactic mastectomy was discussed more frequently with women with medical and allied health training (P=0.02), and prophylactic oophorectomy with women affected with breast cancer (P=0.03), those in non-professional occupations (P=0.04) and with a family history of breast and ovarian cancer (P<0.001). Consultants used significantly more behaviours to facilitate understanding with women who were in non-professional occupations (P=0.04); facilitated active patient involvement more with women affected with breast cancer (P<0.001) and used more supportive and counselling behaviours with affected women (P=0.02). This study showed that patient demographics were more likely to predict consultants' communication behaviours than the woman's psychological status. Methods to facilitate assessment of psychological morbidity are needed to allow more tailored communication.

3629. Mucin gene expression in the ileoanal reservoir is altered and may be relevant to the risk of inflammation and dysplasia.

作者: P A Sylvester.;M Walsh.;N Myerscough.;B F Warren.;A P Corfield.;M G Thomas.;P Durdey.
来源: Gut. 2002年51卷3期386-91页
Adaptive colonic phenotypic change of the ileal mucosa is a feature of the ileoanal reservoir (IAR) with time, as described by mucin glycoprotein and histological analysis. Mucin gene expression is altered in colorectal neoplasia and inflammatory bowel disease but little is known of its expression in the IAR.

3630. Controversies in the current therapy of carcinoma of the esophagus.

作者: Dennis Blom.;Jeffrey H Peters.;Tom R DeMeester.
来源: J Am Coll Surg. 2002年195卷2期241-50页

3631. Phase II randomized study of ISIS 3521 and ISIS 5132 in patients with locally advanced or metastatic colorectal cancer: a National Cancer Institute of Canada clinical trials group study.

作者: M Christine Cripps.;Alvaro T Figueredo.;Amit M Oza.;Marianne J Taylor.;Anthony L Fields.;John T Holmlund.;Lynn W McIntosh.;Richard S Geary.;Elizabeth A Eisenhauer.
来源: Clin Cancer Res. 2002年8卷7期2188-92页
Because treatment of metastatic colon cancer is noncurative, new treatments are needed. This trial evaluated the antitumor effects of two targeted anticancer agents: (a) ISIS 3521, an antisense inhibitor of the protein kinase C alpha; and (b) ISIS 5132, an antisense inhibitor of c-raf kinase in patients untreated previously with recurrent or metastatic colorectal carcinoma.

3632. Overexpression of vascular endothelial growth factor (VEGF) and its cellular receptor KDR (VEGFR-2) in the bone marrow of patients with acute myeloid leukemia.

作者: T Padró.;R Bieker.;S Ruiz.;M Steins.;S Retzlaff.;H Bürger.;T Büchner.;T Kessler.;F Herrera.;J Kienast.;C Müller-Tidow.;H Serve.;W E Berdel.;R M Mesters.
来源: Leukemia. 2002年16卷7期1302-10页
Vascular endothelial growth factor (VEGF) and its cellular receptor VEGFR-2 have been implicated as the main endothelial pathway required for tumor neovascularization. However, the importance of the VEGF/VEGFR-2 system for angiogenesis in hematologic malignancies such as AML remains to be elucidated. In 32 patients with newly diagnosed untreated AML, we observed by immunohistochemical analysis of bone marrow biopsies significantly higher levels of VEGF and VEGFR-2 expression than in 10 control patients (P <0.001). In contrast, VEGFR-1 staining levels in AML patients were in the same range as in the controls. Expression of VEGF and VEGFR-2 was significantly higher in patients with a high degree of microvessel density compared to those with a low degree (VEGF: P =0.024; VEGFR-2: P =0.040) and correlated well with bone marrow microvessel density (r(s)=0.566 and 0.609, respectively; P <0.001). Furthermore, in patients who achieved a complete remission following induction chemotherapy VEGFR-2 staining levels decreased into the normal range. In conclusion, our results provide evidence for increased expression of VEGF/VEGFR-2 of leukemic blasts and correlation with angiogenesis in the bone marrow of AML patients. Thus, VEGF/VEGFR-2 might constitute promising targets for antiangiogenic and antileukemic treatment strategies in AML.

3633. Linkage disequilibrium between the 677C>T and 1298A>C polymorphisms in human methylenetetrahydrofolate reductase gene and their contributions to risk of colorectal cancer.

作者: Jia Chen.;Jing Ma.;Meir J Stampfer.;Caroline Palomeque.;Jacob Selhub.;David J Hunter.
来源: Pharmacogenetics. 2002年12卷4期339-42页
A common polymorphism in a folate-metabolizing gene, methylenetetrahydrofolate reductase (MTHFR) 677C>T has been associated with reduced risk of colorectal cancer. In this study, we investigated whether a second common polymorphism of the gene, MTHFR 1298A>C, is an independent risk factor for colorectal cancer and if it is associated with plasma folate and total homocysteine (tHcy) levels. We also examined whether the 677C>T and 1298A>C polymorphisms are in linkage disequilibrium and whether combined heterozygosity confers additional (or reduced) risk of colorectal cancer. We conducted a nested case-control study of 211 incident colorectal cancer cases and 343 controls in the prospective Physicians' Health Study. The MTHFR 677C>T and 1298A>C polymorphisms were in linkage disequilibrium in this population. Compared to MTHFR 1298AA genotype, multivariate-adjusted relative risk of colorectal cancer was 0.73 (95% CI 0.37-1.43) for the MTHFR 1298CC genotype. The slight reduction in risk was not a result of its linkage disequilibrium with the 677C>T polymorphism. This polymorphism was not significantly correlated with the plasma folate and tHcy levels. The combined heterozygosity did not modify the cancer risk; nor did it change the plasma folate and tHcy significantly. We conclude that the MTHFR 1298A>C polymorphism is a less substantial independent risk factor for colorectal cancer compared to the 677C>T polymorphism.

3634. Family history and prostate cancer screening with prostate-specific antigen.

作者: Tuukka Mäkinen.;Teuvo L J Tammela.;Ulf-Håkan Stenman.;Liisa Määttänen.;Sakari Rannikko.;Jussi Aro.;Harri Juusela.;Matti Hakama.;Anssi Auvinen.
来源: J Clin Oncol. 2002年20卷11期2658-63页
Early detection of prostate cancer has been recommended for men with affected first-degree relatives despite the lack of evidence for mortality reduction. We therefore evaluated the impact of family history in the Finnish prostate cancer screening trial.

3635. K-ras mutations in sporadic colorectal tumors in Israel: unusual high frequency of codon 13 mutations and evidence for nonhomogeneous representation of mutation subtypes.

作者: Dmitry Kislitsin.;Aaron Lerner.;Gad Rennert.;Zeev Lev.
来源: Dig Dis Sci. 2002年47卷5期1073-9页
Colorectal cancer is one of the most common malignancies in the western world, including Israel. An important step in progression includes induction of activating mutations in the protooncogene K-ras. This event is very frequent and is detected in about 40% of colorectal carcinomas. Previous studies of a variety of genetic disorders revealed unique gene mutation prevalence in Jewish populations, attributed both to differences in genetic background and to variability in environmental exposure. To determine the incidence and molecular subtypes of K-ras mutations in colorectal cancer in Israel, compared with other countries, DNA was isolated from a random collection of 105 colorectal carcinoma samples, and K-ras mutations were detected by an improved designed RFLP and direct sequencing. K-ras sporadic mutations in colorectal cancer in Israel are relatively frequent, with a higher fraction in codon 13 than reported thus far. Comparison with other countries shows a vast heterogeneity in terms of the relative abundance of the affected K-ras codon and in type and representation of specific mutations. The heterogeneous distribution found may be due to a variable genetic background and different environmental factors involved in the initiation and propagation of sporadic colorectal cancer.

3636. HER-2 amplification and topoisomerase IIalpha gene aberrations as predictive markers in node-positive breast cancer patients randomly treated either with an anthracycline-based therapy or with cyclophosphamide, methotrexate, and 5-fluorouracil.

作者: Angelo Di Leo.;David Gancberg.;Denis Larsimont.;Minna Tanner.;Tero Jarvinen.;Ghizlane Rouas.;Stella Dolci.;Jean-Yves Leroy.;Marianne Paesmans.;Jorma Isola.;Martine J Piccart.
来源: Clin Cancer Res. 2002年8卷5期1107-16页
The purpose of this study is to evaluate HER-2 and topoisomerase IIalpha (topo IIalpha) as candidates for predicting the activity of anthracyclines in the adjuvant treatment of breast cancer patients.

3637. Primary chemoprevention of familial adenomatous polyposis with sulindac.

作者: Francis M Giardiello.;Vincent W Yang.;Linda M Hylind.;Anne J Krush.;Gloria M Petersen.;Jill D Trimbath.;Steven Piantadosi.;Elizabeth Garrett.;Deborah E Geiman.;Walter Hubbard.;G Johan A Offerhaus.;Stanley R Hamilton.
来源: N Engl J Med. 2002年346卷14期1054-9页
Familial adenomatous polyposis is caused by a germ-line mutation in the adenomatous polyposis coli gene and is characterized by the development of hundreds of colorectal adenomas and, eventually, colorectal cancer. Nonsteroidal antiinflammatory drugs can cause regression of adenomas, but whether they can prevent adenomas is unknown.

3638. Contribution of cyclin d1 (CCND1) and E-cadherin (CDH1) polymorphisms to familial and sporadic colorectal cancer.

作者: Timothy R Porter.;Frances M Richards.;Richard S Houlston.;D Gareth R Evans.;Janusz A Jankowski.;Fiona Macdonald.;Gail Norbury.;Stewart J Payne.;Samantha A Fisher.;Ian Tomlinson.;Eamonn R Maher.
来源: Oncogene. 2002年21卷12期1928-33页
The molecular basis for most non-HNPCC familial colorectal cancer cases is unknown, but there is increasing evidence that common genetic variants may play a role. We investigated the contribution of polymorphisms in two genes implicated in the pathogenesis of colorectal cancer, cyclin D1 (CCND1) and E-cadherin (CDH1), to familial and sporadic forms of the disease. The CCND1 870A/G polymorphism is thought to affect the expression of CCND1 through mRNA splicing and has been reported to modify the penetrance of HNPCC. Inactivation of E-cadherin is common in colorectal cancer, and truncating germline mutations have been reported to confer susceptibility to colorectal as well as diffuse gastric cancer. The -160A/C CDH1 polymorphism appears to affect expression of CDH1 and may therefore also confer an increased risk. We found a significantly higher frequency of CCND1 870A allele in 206 familial cases compared to 171 controls (P=0.03). Odds ratios in heterozygotes and homozygotes were 1.7 (95% CI: 1.0-2.66) and 1.8 (95% CI: 1.0-3.3) respectively. The difference was accounted for by an over-representation of A allele in non-HNPCC familial cases (P=0.007). Over-representation of the CCND1 A allele was also seen in sporadic colorectal cancer cases compared to controls but this did not attain statistical significance (P=0.08). No significant differences between the frequency of CDH1 -160A/C genotypes in familial, sporadic colorectal cancer cases and controls were seen, although a possible association between the low expressing A allele and right-sided tumours was detected in familial cases.

3639. A randomized trial of specialist genetic assessment: psychological impact on women at different levels of familial breast cancer risk.

作者: K Brain.;P Norman.;J Gray.;C Rogers.;R Mansel.;P Harper.
来源: Br J Cancer. 2002年86卷2期233-8页
The aim was to compare the psychological impact of a multidisciplinary specialist genetics service with surgical provision in women at high risk and those at lower risk of familial breast cancer. Women (n=735) were randomized to a surgical consultation with (trial group) or without (control group) specialist genetic risk assessment and the possible offer of presymptomatic genetic testing. Participants completed questionnaires before and immediately after the consultation to assess anxiety, cancer worry, perceived risk, interest in genetic testing and satisfaction. Responses of subgroups of women stratified by clinicians as low, moderate, or high risk were analyzed. There were no significant main effects of study intervention on any outcome variable. Regardless of risk information, there was a statistically significant reduction in state anxiety (P<0.001). Reductions in cancer worry and perceived risk were significant for women at low or moderate risk (P<0.001) but not those at high risk, and satisfaction was significantly lower in the high risk group (P<0.001). In high risk women who received specialist genetic input, there was a marginally significant trend towards increased perceived risk. The effect of risk information on interest in genetic testing was not significant. Breast care specialists other than geneticists might provide assessments of breast cancer risk, reassuring women at reduced risk and targeting those at high risk for specialist genetic counselling and testing services. These findings are discussed in relation to the existing UK Calman-Hine model of service delivery in cancer genetics. DOI: 10.1038/sj/bjc/6600051 www.bjcancer.comCopyright 2002 The Cancer Research Campaign

3640. Microsatellite instability and cytogenetic survey in myeloid leukemias.

作者: E M S F Ribeiro.;J M Rodriguez.;V M Cóser.;M G Sotero.;J M Fonseca Neto.;R Pasquini.;I J Cavalli.
来源: Braz J Med Biol Res. 2002年35卷2期153-9页
Microsatellites are short tandem repeat sequences dispersed throughout the genome. Their instability at multiple genetic loci may result from mismatch repair errors and it occurs in hereditary nonpolyposis colorectal cancer. This instability is also found in many sporadic cancers. In order to evaluate the importance of this process in myeloid leukemias, we studied five loci in different chromosomes of 43 patients, 22 with chronic myelocytic leukemia (CML) in the chronic phase, 7 with CML in blast crisis, and 14 with acute myeloid leukemia (AML), by comparing leukemic DNA extracted from bone marrow and constitutional DNA obtained from buccal epithelial cells. Only one of the 43 patients (2.1%), with relapsed AML, showed an alteration in the allele length at a single locus. Cytogenetic analysis was performed in order to improve the characterization of leukemic subtypes and to determine if specific chromosome aberrations were associated with the presence of microsatellite instability. Several chromosome aberrations were observed, most of them detected at diagnosis and during follow-up of the patients, according to current literature. These findings suggest that microsatellite instability is an infrequent genetic event in myeloid leukemias, adding support to the current view that the mechanisms of genomic instability in solid tumors differ from those observed in leukemias, where specific chromosome aberrations seem to play a major role.
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