273 research outputs found

    Overcoming evasive resistance from vascular endothelial growth factor a inhibition in sarcomas by genetic or pharmacologic targeting of hypoxia-inducible factor 1Ī±

    Get PDF
    Increased levels of hypoxia and hypoxia-inducible factor 1Ī± (HIF-1Ī±) in human sarcomas correlate with tumor progression and radiation resistance. Prolonged antiangiogenic therapy of tumors not only delays tumor growth but may also increase hypoxia and HIF-1Ī± activity. In our recent clinical trial, treatment with the vascular endothelial growth factor A (VEGF-A) antibody, bevacizumab, followed by a combination of bevacizumab and radiation led to near complete necrosis in nearly half of sarcomas. Gene Set Enrichment Analysis of microarrays from pretreatment biopsies found that the Gene Ontology category ā€œResponse to hypoxiaā€ was upregulated in poor responders and that the hierarchical clustering based on 140 hypoxia-responsive genes reliably separated poor responders from good responders. The most commonly used chemotherapeutic drug for sarcomas, doxorubicin (Dox), was recently found to block HIF-1Ī± binding to DNA at low metronomic doses. In four sarcoma cell lines, HIF-1Ī± shRNA or Dox at low concentrations blocked HIF-1Ī± induction of VEGF-A by 84ā€“97% and carbonic anhydrase 9 by 83ā€“93%. HT1080 sarcoma xenografts had increased hypoxia and/or HIF-1Ī± activity with increasing tumor size and with anti-VEGF receptor antibody (DC101) treatment. Combining DC101 with HIF-1Ī± shRNA or metronomic Dox had a synergistic effect in suppressing growth of HT1080 xenografts, at least in part via induction of tumor endothelial cell apoptosis. In conclusion, sarcomas respond to increased hypoxia by expressing HIF-1Ī± target genes that may promote resistance to antiangiogenic and other therapies. HIF-1Ī± inhibition blocks this evasive resistance and augments destruction of the tumor vasculature. Whatā€™s new? Despite their initial promise, anti-angiogenic therapies have been a disappointment in the clinic. One reason is that solid tumors often become resistant to these drugs. Tumors that respond poorly to this type of therapy have increased activation of the hypoxia-induced transcription factor HIF-1Ī± which can enhance tumor survival and progression. In this study, the authors report that this evasive resistance can be overcome by adding low-dose doxorubicin or shRNA to inhibit HIF-1Ī± activity. They are thus developing a clinical trial combining the angiogenesis inhibitor bevacizumab with metronomic doxorubicin in sarcoma patients

    Incidence of acute cerebrovascular events in patients with rheumatic or calcific mitral stenosis: a systematic review and meta-analysis

    Get PDF
    Background Patients with mitral stenosis (MS) may be predisposed to acute cerebrovascular events (ACE) and peripheral thromboembolic events (TEE). Concomitant atrial fibrillation (AF), mitral annular calcification (MAC) and rheumatic heart disease (RHD) are independent risk factors. Our aim was to evaluate the incidence of ACEs in MS patients and the implications of AF, MAC, and RHD on thromboembolic risks. Methods This systematic review was registered on PROSPERO (CRD42021291316). Six databases were searched from inception to 19th December 2021. The clinical outcomes were composite ACE, ischaemic stroke/transient ischaemic attack (TIA), and peripheral TEE. Results We included 16 and 9 papers, respectively, in our qualitative and quantitative analyses. The MS cohort with AF had the highest incidence of composite ACE (31.55%; 95%CI 3.60-85.03; I 2 =99%), followed by the MAC (14.85%; 95%CI 7.21-28.11; I 2 =98%), overall MS (8.30%; 95%CI 3.45-18.63; I 2 =96%) and rheumatic MS population (4.92%; 95%CI 3.53-6.83; I 2 =38%). Stroke/TIA were reported in 29.62% of the concomitant AF subgroup (95%CI 2.91-85.51; I 2 =99%) and in 7.11% of the overall MS patients (95%CI 1.91-23.16; I 2 =97%). However, the heterogeneity of the pooled incidence of clinical outcomes in all groups, except the rheumatic MS group, were substantial and significant. The logit-transformed proportion of composite ACE increased by 0.0141 (95% CI 0.0111-0.0171; p<0.01) per year of follow-up. Conclusion In the MS population, MAC and concomitant AF are risk factors for the development of ACE. The scarcity of data in our systematic review reflects the need for further studies to explore thromboembolic risks in all MS subtypes

    Gemcitabine and cisplatin in a multimodality treatment for locally advanced non-small cell lung cancer

    Get PDF
    The role of new cytotoxic agents like gemcitabine has not yet been proven in the neoadjuvant settings. We designed a phase II study to test the feasibility of using gemcitabine and cisplatin before local treatment for stage III non-small cell lung cancer patients. Patients received three cycles of induction chemotherapy of gemcitabine (1000ā€‰mgā€‰māˆ’2, days 1, 8, 15) and cisplatin (90ā€‰mgā€‰māˆ’2, day 15) every 4 weeks before evaluation for operability. Operable patients underwent radical resection. Inoperable patients and patients who had incomplete resection received concurrent chemoradiotherapy with daily low dose cisplatin. All patients who did not progress after local treatment received three more cycles of adjuvant chemotherapy of gemcitabine and cisplatin. Fifty-two patients received induction treatment. Two patients had complete response and 31 patients had partial response (response rate 63.5%) after induction chemotherapy. Thirty-six patients (69%) were operable. Eighteen patients (35%) had their tumours completely resected. Two patients had pathological complete response. Median overall survival was 19.1 months, projected 1-year survival was 66% and 2-year survival was 34%. Three cycles of gemcitabine and cisplatin is effective and can be used as induction treatment before surgery for locally advanced non-small cell lung cancer patients

    Independent Predictors of Cardiac Mortality and Hospitalization for Heart Failure in a Multi-Ethnic Asian ST-segment Elevation Myocardial Infarction Population Treated by Primary Percutaneous Coronary Intervention

    Get PDF
    We aimed to identify independent predictors of cardiac mortality and hospitalization for heart failure (HHF) from a real-world, multi-ethnic Asian registry [the Singapore Myocardial Infarction Registry] of ST-segment elevation myocardial infarction (STEMI) patients treated by primary percutaneous coronary intervention. 11,546 eligible STEMI patients between 2008 and 2015 were identified. In-hospital, 30-day and 1-year cardiac mortality and 1-year HHF rates were 6.4%, 6.8%, 8.3% and 5.2%, respectively. From the derivation cohort (70% of patients), age, Killip class and cardiac arrest, creatinine, hemoglobin and troponin on admission and left ventricular ejection fraction (LVEF) during hospitalization were predictors of in-hospital, 30-day and 1-year cardiac mortality. Previous ischemic heart disease (IHD) was a predictor of in-hospital and 30-day cardiac mortality only, whereas diabetes was a predictor of 1-year cardiac mortality only. Age, previous IHD and diabetes, Killip class, creatinine, hemoglobin and troponin on admission, symptom-to-balloon-time and LVEF were predictors of 1-year HHF. The c-statistics were 0.921, 0.901, 0.881, 0.869, respectively. Applying these models to the validation cohort (30% of patients) showed good fit and discrimination (c-statistic 0.922, 0.913, 0.903 and 0.855 respectively; misclassification rate 14.0%, 14.7%, 16.2% and 24.0% respectively). These predictors could be incorporated into specific risk scores to stratify reperfused STEMI patients by their risk level for targeted intervention

    Resectable adenocarcinomas in the pancreatic head: the retroperitoneal resection margin is an independent prognostic factor

    Get PDF
    Pancreatic cancer is a lethal disease, and even after assumed margin-free pancreatoduodenectomy, most patients die within few years. The aims were to evaluate the importance of standardised histopathologic assessment for adequacy of reporting and survival estimates, and to report on prognostic factors in a setting of standardised histopathologic assessment. We performed immunohistochemical evaluation, slide review, and review of histopathologic reports from all pancreatoduodenectomies at Rikshospitalet University Hospital in 1980ā€“2004. Reports from 1998-2004 at this institution were compared with reports from all other Norwegian institutions in the same period. Standardised histopathologic assessment and reporting was found necessary to avoid underestimation of poor prognostic factors, and to avoid misdiagnosis of tumours originating from non-pancreatic tissue (ampulla, distal bile duct, duodenum). Standardised histopathology was more important than surgical volume for completeness of reporting and for reliability of survival estimates, particularly with respect to lymph node evaluation. Immunostaining for MUC1 and MUC4 identified a subgroup of patients with particularly poor prognosis. Standardised histopathologic evaluation should be a first prerequisite to assure adequate histopathology after pancreatoduodenectomy. Immunostaining may identify tumour markers potentially targetable in future adjuvant treatments for pancreatic cancer

    Identification of a Danish breast/ovarian cancer family double heterozygote for BRCA1 and BRCA2 mutations

    Get PDF
    Mutations in the two breast cancer susceptibility genes BRCA1 and BRCA2 are associated with increased risk of breast and ovarian cancer. Patients with mutations in both genes are rarely reported and often involve Ashkenazi founder mutations. Here we report the first identification of a Danish breast and ovarian cancer family heterozygote for mutations in the BRCA1 and BRCA2 genes. The BRCA1 nucleotide 5215GĀ >Ā A/c.5096GĀ >Ā A mutation results in the missense mutation Arg1699Gln, while the BRCA2 nucleotide 859Ā +Ā 4AĀ >Ā G/c.631Ā +Ā 4AĀ >Ā G is novel. Exon trapping experiments and reverse transcriptase (RT)ā€“PCR analysis revealed that the BRCA2 mutation results in skipping of exon 7, thereby introducing a frameshift and a premature stop codon. We therefore classify the mutation as disease causing. Since the BRCA1 Arg1699Gln mutation is also suggested to be disease-causing, we consider this family double heterozygote for BRCA1 and BRCA2 mutations
    • ā€¦
    corecore