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81.
Poor prognosis in carcinoma is associated with a gene expression signature of aberrant PTEN tumor suppressor pathway activity 总被引:7,自引:0,他引:7 下载免费PDF全文
Saal LH Johansson P Holm K Gruvberger-Saal SK She QB Maurer M Koujak S Ferrando AA Malmström P Memeo L Isola J Bendahl PO Rosen N Hibshoosh H Ringnér M Borg A Parsons R 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(18):7564-7569
Pathway-specific therapy is the future of cancer management. The oncogenic phosphatidylinositol 3-kinase (PI3K) pathway is frequently activated in solid tumors; however, currently, no reliable test for PI3K pathway activation exists for human tumors. Taking advantage of the observation that loss of PTEN, the negative regulator of PI3K, results in robust activation of this pathway, we developed and validated a microarray gene expression signature for immunohistochemistry (IHC)-detectable PTEN loss in breast cancer (BC). The most significant signature gene was PTEN itself, indicating that PTEN mRNA levels are the primary determinant of PTEN protein levels in BC. Some PTEN IHC-positive BCs exhibited the signature of PTEN loss, which was associated to moderately reduced PTEN mRNA levels cooperating with specific types of PIK3CA mutations and/or amplification of HER2. This demonstrates that the signature is more sensitive than PTEN IHC for identifying tumors with pathway activation. In independent data sets of breast, prostate, and bladder carcinoma, prediction of pathway activity by the signature correlated significantly to poor patient outcome. Stathmin, encoded by the signature gene STMN1, was an accurate IHC marker of the signature and had prognostic significance in BC. Stathmin was also pathway-pharmacodynamic in vitro and in vivo. Thus, the signature or its components such as stathmin may be clinically useful tests for stratification of patients for anti-PI3K pathway therapy and monitoring therapeutic efficacy. This study indicates that aberrant PI3K pathway signaling is strongly associated with metastasis and poor survival across carcinoma types, highlighting the enormous potential impact on patient survival that pathway inhibition could achieve. 相似文献
82.
Background:
Management of femoral diaphyseal fractures in the age group of 6-16 years is controversial. There has been a resurgence worldwide for operative fixation.Materials and Methods:
Twenty-two children (18 boys, 4 girls) aged 6-16 years with recent (> 3 days) femoral diaphyseal fractures (20 closed, 2 open) were stabilized with Titanium Elastic Nail (TEN). These fractures were in proximal third (n=3), middle third (n=15) and in the distal third (n=4) 17 patients underwent surgery within seven days of their injury. The results were evaluated using Flynn''s scoring criteria. Statistical analysis was done using Fischer''s exact test.Results:
All 22 patients were available for evaluation after a mean of 26 months (14-36 months) of followup. Radiological union in all cases were achieved in a mean time of 8.7 weeks. Full weight bearing was possible in a mean time of 8.8 weeks. Mean duration of hospital stay was 9.8 days. The results were excellent in 13 patients (59.0%), successful in six (27.2%) and poor in three patients (13.6%). All patients had early return to school.Conclusion:
Intramedullary fixation titanium elastic nailing is an effective treatment of diaphyseal fractures of the femur in properly selected patients of the 6-16 years age group. 相似文献83.
Linderholm BK Gruvberger-Saal S Gruvbreger-Saal S Fernö M Bendahl PO Malmström P 《Breast (Edinburgh, Scotland)》2008,17(5):484-491
We investigate the prognostic significance of the pro-angiogenic cytokine vascular endothelial growth factor (VEGF), urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor 1 (PAI-1), and S-phase fraction (SPF) for distant disease free survival (DDFS) in 219 premenopausal patients with node-negative breast cancer (NNBC). In univariate analysis significantly shorter DDFS was observed for patients with high VEGF (p=0.006), high uPA (p=0.001), and high SPF (p<0.001). The prognostic significance of VEGF varied over time being very strong for early relapses (0-2.25 years follow-up) (HR=7.9; p=0.006) while no difference was seen in the subsequent follow-up period (HR=1.3; p=0.62). In a series of bivariate analyses VEGF provided prognostic information during the whole observation period (0-72 months) in addition to age, tumour size, oestrogen receptor (ER), progesterone receptor (PgR), and uPA. Also this effect was more pronounced during the first follow-up period suggesting VEGF as a marker of early recurrences. 相似文献
84.
Basal-like phenotype is not associated with patient survival in estrogen-receptor-negative breast cancers 总被引:5,自引:1,他引:4 下载免费PDF全文
Jumppanen M Gruvberger-Saal S Kauraniemi P Tanner M Bendahl PO Lundin M Krogh M Kataja P Borg A Fernö M Isola J 《Breast cancer research : BCR》2007,9(1):R16-10
Introduction
Basal-phenotype or basal-like breast cancers are characterized by basal epithelium cytokeratin (CK5/14/17) expression, negative estrogen receptor (ER) status and distinct gene expression signature. We studied the clinical and biological features of the basal-phenotype tumors determined by immunohistochemistry (IHC) and cDNA microarrays especially within the ER-negative subgroup.Methods
IHC was used to evaluate the CK5/14 status of 445 stage II breast cancers. The gene expression signature of the CK5/14 immunopositive tumors was investigated within a subset (100) of the breast tumors (including 50 ER-negative tumors) with a cDNA microarray. Survival for basal-phenotype tumors as determined by CK5/14 IHC and gene expression signature was assessed.Results
From the 375 analyzable tumor specimens, 48 (13%) were immunohistochemically positive for CK5/14. We found adverse distant disease-free survival for the CK5/14-positive tumors during the first years (3 years hazard ratio (HR) 2.23, 95% confidence interval (CI) 1.17 to 4.24, p = 0.01; 5 years HR 1.80, 95% CI 1.02 to 3.15, p = 0.04) but the significance was lost at the end of the follow-up period (10 years HR 1.43, 95% CI 0.84 to 2.43, p = 0.19). Gene expression profiles of immunohistochemically determined CK5/14-positive tumors within the ER-negative tumor group implicated 1,713 differently expressed genes (p < 0.05). Hierarchical clustering analysis with the top 500 of these genes formed one basal-like and a non-basal-like cluster also within the ER-negative tumor entity. A highly concordant classification could be constructed with a published gene set (Sorlie's intrinsic gene set, concordance 90%). Both gene sets identified a basal-like cluster that included most of the CK5/14-positive tumors, but also immunohistochemically CK5/14-negative tumors. Within the ER-negative tumor entity there was no survival difference between the non-basal and basal-like tumors as identified by immunohistochemical or gene-expression-based classification.Conclusion
Basal cytokeratin-positive tumors have a biologically distinct gene expression signature from other ER-negative tumors. Even if basal cytokeratin expression predicts early relapse among non-selected tumors, the clinical outcome of basal tumors is similar to non-basal ER-negative tumors. Immunohistochemically basal cytokeratin-positive tumors almost always belong to the basal-like gene expression profile, but this cluster also includes few basal cytokeratin-negative tumors. 相似文献85.
JK Gass SK Chan E Rytina DC Greenberg NP Burrows 《Journal of the European Academy of Dermatology and Venereology》2010,24(5):601-603
Background Merkel cell carcinoma (MCC) is a rare malignant cutaneous tumour, the incidence of which is increasing. Second malignancies have been reported to occur with high incidence in these patients. Objectives We report the rate and nature of multiple malignancies in patients with MCC treated over a 10 year period in Addenbrooke’s Hospital in Cambridge, United Kingdom, as well as the temporal relationship of these additional malignancies to the diagnosis of MCC. Results The 27 patients had an approximately equal sex incidence with a median age at diagnosis of 79 years. Seventy percent (n=19) of patients had a second primary malignant tumour; and 7 of these patients had two or more tumours in addition to the MCC. Eighteen patients had additional cutaneous malignancies: melanoma, squamous cell carcinoma and basal cell carcinoma, and 8 patients presented non‐cutaneous malignancy including colorectal, haematological and breast tumours. Of the 28 additional tumours in our patients, half were diagnosed prior to presentation of MCC, 32% within 6 months of diagnosis, and 18% between 6 months and 3 years after diagnosis. Possible reasons for the high rate of additional tumours in this population are discussed. Conclusions Our figures reflect a higher incidence of multiple malignancies in those with Merkel cell tumour than has previously been reported. This has important implications for the care and surveillance of these patients. 相似文献
86.
SK Ghosh D Bandyopadhyay A Ghosh 《Journal of the European Academy of Dermatology and Venereology》2010,24(2):214-218
Background Symmetrical peripheral gangrene (SPG) is characterized by sudden onset of peripheral, frequently symmetrical gangrene in the absence of major vascular occlusive disease. SPG is associated with a wide range of underlying medical problems and usually has disseminated intravascular coagulation (DIC) in the background. Although sporadic cases and a few retrospective case series of SPG have been reported, lack of any prospective study on the profile and outcome of these patients prompted us to undertake the present work. Objectives To study the clinical profile, aetiological factors, and outcome of a group of patients of SPG from eastern India. Patients/methods Prospective, observational study of consecutive patients presented at or referred to the Dermatology Department of a tertiary‐care hospital during 2001 to 2008. Results We observed 14 patients (5 males, 9 females; mean age: 43.36 years) of SPG during the study period. All had clinical and laboratory evidence of DIC in association with a shock syndrome. Associated purpura fulminans was noted in 11 patients. In 12 patients, the cause of SPG was infective, Pneumococcus being the commonest organism involved. Two patients developed DIC and SPG postoperatively. Nine patients survived and the remaining five patients died. Three patients had leukopenia and all of them died. Amongst the survivors, four patients had auto‐amputation of some parts of distal limbs; surgical amputation was done in two patients. Conclusions SPG carries a high mortality rate frequently requiring multiple limb amputations in survivors. Leukopenia may be a poor prognostic factor of SPG and DIC may occur universally. 相似文献
87.
The right mid-lung window 总被引:1,自引:0,他引:1
Goodman LR; Golkow RS; Steiner RM; Teplick SK; Haskin ME; Himmelstein E; Teplick JG 《Radiology》1982,143(1):135
88.
Aneurysm of sinus of Valsalva dissecting into interventricular septum is a rare entity. We report one such case who was incidentally diagnosed by echocardiography to have this abnormality during evaluation of a clinically suspected isolated aortic regurgitation.KEY WORDS: Aneurysm – dissecting – sinus of Valsalva, Echocardiography 相似文献
89.
B Airan Ch SK Choudhary M. Ch CSK Ready M. Ch A Saxena DM SS Kothari DM IM Rao M.Ch P Venugopal M.Ch 《Indian Journal of Thoracic and Cardiovascular Surgery》2000,16(1):15-18
Introduction The Fontan procedure has undergone many modifications to avoid atrial arrhythmias and thrombus formation. We used patient’s
interatrial septum as a flap to direct the inferior venacaval blood to the superior venacava.
Methods Seventeen patients, aged 1 to 17 years, underwent modified total cavopulmonary anastomosis. Interatrial septum was used to
create the inner half of the atrial tunnel, outer half being formed by right atrial free wall. Post-operatively, all patients
underwent echocardiography. Seven patients underwent 24 hour ambulatory Holter monitoring and 6 patients underwent cardiac
catheterization and cineangiography.
Results There was one early death due to low cardiac output. One patient had transient supraventricular arrhythmia. Two patients had
singnificant pleural effusion. Holter Monitoring reveled sinus rhythm in all 7 patients studied. Follow up ranged from 18
to 60 months and patients were evaluated as they came for follow up. Long term follow up is currently being compiled. There
was one late death from a non-cardiac cause. The remaining patients were in New York Heart Association (NYHA) Class I or II.
All patients were in sinus rhythm. Echocardiography and cineangiography revealed absence of obstruction or leak.
Conclusions Total cavopulmonary anastomosis using autogenous atrial septum is a useful modification for classical cavopulmonary anastomosis
and provides good early results. 相似文献
90.
目的 了解不同的心肌保护方法是否对体外循环 (ECC)术后房性心律失常有影响。 方法 将 12只成年杂交犬随机分为两组 ,A组 :6只犬 ,用持续温血心脏停搏液灌注 ;B组 :6只犬 ,用冷晶体心脏停搏液灌注和局部低温。两组动物主动脉阻断时间均为 30分钟。记录术前及术后 1~ 5天 2 4小时动态心电图 ,计算标准化房性心律失常 ,标准化室性心律失常和 2 4小时平均心率。 结果 ECC后两组动物均未出现心房颤动。尽管术后 A组标准化房性心律失常率高于 B组 (P<0 .0 5 ) ,但两组动物术前、术后标准化房性心律失常率无明显变化 ,标准化室性心律失常率亦无明显变化。此外 ,两组动物术后 2 4小时平均心率亦升高 ,且 B组高于 A组 (P<0 .0 5 )。 结论 不同的心肌保护方法对 ECC术后房性心律失常的发生无明显影响。 相似文献