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1.
Usha Patel Manish Pandey Sadhana Kannan Tanuja A. Samant Poonam Gera Neha Mittal Swapnil Rane Asawari Patil Vanita Noronha Amit Joshi Vijay M. Patil Kumar Prabhash Manoj B. Mahimkar 《British journal of cancer》2020,123(12):1757
Background Anti-EGFR-based therapies have limited success in HNSCC patients. Predictive biomarkers are greatly needed to identify the patients likely to be benefited from these targeted therapies. Here, we present the prognostic and predictive association of biomarkers in HPV-negative locally advanced (LA) HNSCC patients.Methods Treatment-naive tumour tissue samples of 404 patients, a subset of randomised Phase 3 trial comparing cisplatin radiation (CRT) versus nimotuzumab plus cisplatin radiation (NCRT) were analysed to evaluate the expression of HIF1α, EGFR and pEGFR by immunohistochemistry and EGFR gene copy change by FISH. Progression-free survival (PFS), locoregional control (LRC) and overall survival (OS) were estimated by Kaplan–Meier method. Hazard ratios were estimated by Cox proportional hazard models.Results Baseline characteristics of the patients were balanced between two treatment groups (CRT vs NCRT) and were representative of the trial cohort. The median follow-up was of 39.13 months. Low HIF1α was associated with better PFS [HR (95% CI) = 0.62 (0.42–0.93)], LRC [HR (95% CI) = 0.56 (0.37–0.86)] and OS [HR (95% CI) = 0.63 (0.43–0.93)] in the CRT group. Multivariable analysis revealed HIF1α as an independent negative prognostic biomarker. For patients with high HIF1α, NCRT significantly improved the outcomes [PFS:HR (95% CI) = 0.55 (0.37–0.82), LRC:HR (95% CI) = 0.55 (0.36–0.85) and OS:HR (95% CI) = 0.54 (0.36–0.81)] compared to CRT. While in patients with low HIF1α, no difference in the clinical outcomes was observed between treatments. Interaction test suggested a predictive value of HIF1α for OS (P = 0.008).Conclusions High HIF1α expression is a predictor of poor clinical response to CRT in HPV-negative LA-HNSCC patients. These patients with high HIF1α significantly benefited with the addition of nimotuzumab to CRT.Clinical trial registration Registered with the Clinical Trial Registry of India (Trial registration identifier—CTRI/2014/09/004980).Subject terms: Tumour biomarkers, Head and neck cancer, Tumour biomarkers, Head and neck cancer, Predictive markers 相似文献
2.
Myectomy versus myotomy as an adjunct to membranectomy in the surgical repair of discrete and tunnel subaortic stenosis 总被引:1,自引:0,他引:1
J Lavee L Porat A Smolinsky J Hegesh H N Neufeld D A Goor 《The Journal of thoracic and cardiovascular surgery》1986,92(5):944-949
The results of membranectomy and deep myectomy in the left ventricular outflow tract were compared to those of membranectomy and myotomy in 42 patients who underwent surgical repair of discrete and tunnel subaortic stenosis. Fifteen consecutive patients (Group A) underwent membranectomy and myotomy, and 27 consecutive patients (Group B) underwent membranectomy and myectomy. Two patients of Group A and nine of Group B had tunnel subaortic stenosis. The preoperative mean (+/- standard deviation) peak systolic gradients across the left ventricular outflow tract in patients with discrete subaortic stenosis types I and II were 64 +/- 29 mm Hg in Group A and 52 +/- 3 mm Hg in Group B (p = not significant). In the patients with tunnel subaortic stenosis the preoperative mean gradients were 97 +/- 74 mm Hg in Group A and 73 +/- 26 mm Hg in Group B (p = not significant). In patients with discrete subaortic stenosis types I and II, postoperative catheterization at a mean follow-up of 21 months revealed residual mean gradients of 29 +/- 24 mm Hg in Group A and 10 +/- 13 mm Hg in Group B (p less than 0.01). In the patients with tunnel subaortic stenosis, the postoperative mean gradients were 25 +/- 7 and 30 +/- 30 mm Hg in Groups A and B, respectively (p = not significant). We conclude that in the surgical management of discrete subaortic stenosis types I and II, deep myectomy (in addition to membranectomy) produces better relief of the left ventricular outflow obstruction than do membranectomy and myotomy. In patients with tunnel subaortic stenosis myectomy is less effective than in the non-tunnel type but still produces acceptable results and may delay radical procedures to a later age. 相似文献
3.
Gera D Eytan 《Biomedicine & Pharmacotherapy》2005,59(3):90-97
Passive uptake of drugs into cells is described in terms of the following steps: (1) massive immediate binding of the drugs to the outer leaflet of the plasma membrane resulting in practical equilibrium between extremely high drug concentrations at the cell surface compared to the drug concentration in the medium. (2) Due to their amphipathic nature, anticancer drugs are practically excluded from the lipid core of the membrane. They cross the lipid core by distinct flip-flop events that occur in the case of doxorubicin and daunorubicin after an average period of 0.7 and 0.15 min, respectively. (3) The drug reaching the inner leaflet of the plasma membrane is in practical equilibrium with the drug present in the cytoplasm. (4) Almost all the amounts of anticancer drugs present in the cells are bound by molecular sinks, such as DNA or cytoskeleton elements. The resistance afforded to multidrug resistant (MDR) cells by extrusion pumps, such as P-glycoprotein, is negatively correlated with the affinity of the drugs to the membranes and with their flip-flop rates across membranes. Binding rates of the drugs to membranes and intracellular sinks have no effect on drug concentration in the cytoplasm once equilibrium is reached between the passive uptake of drugs and their active extrusion. 相似文献
4.
Sequence-specific DNA binding of individual cut repeats of the human CCAAT displacement/cut homeodomain protein. 总被引:14,自引:0,他引:14 下载免费PDF全文
B Aufiero E J Neufeld S H Orkin 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(16):7757-7761
CCAAT displacement protein (CDP), a nuclear protein of 180-190 kDa, contains a triplicated motif, the cut domain, similar (80-90% conserved) to three repeats of 60-65 amino acids first identified in Drosophila cut, a homeo-domain protein involved in cell-fate decisions in development. Cut repeats bind DNA and exhibit subtle differences in target-site recognition. DNA sequences specifically bound by cut repeats were isolated by PCR-mediated DNA target-site selection. Sequences selected for cut repeat 2 and 3 (CR2 and CR3) binding are A+T-rich and favor an ATA motif with similar, but not identical, flanking base preferences. CR2 and CR3 discriminate among similar target sequences. CR1, which is more divergent from CR2 and CR3, displays the most restricted pattern of DNA sequence recognition. Methylation interference analysis demonstrates different protein-DNA contacts for CR1 and CR3 binding to a target sequence. Thus, CDP/cut is a complex protein whose DNA-binding properties reflect the combinatorial interaction of four domains (three cut repeats and one homeodomain) with target DNA sequences. 相似文献
5.
Yu WH Zhao KW Ryazantsev S Rozengurt N Neufeld EF 《Molecular genetics and metabolism》2000,71(4):573-580
The Sanfilippo syndrome type B (MPS III B) is an autosomal recessive disease caused by deficiency of alpha-N-acetylglucosaminidase (EC 3. 2.1.50), one of the lysosomal enzymes required for the degradation of heparan sulfate. The disease is characterized by profound neurodegeneration but relatively mild somatic manifestations, and is usually fatal in the second decade. A mouse model had been generated by disruption of the Naglu gene in order to facilitate the study of pathogenesis and the development of therapy for this currently untreatable disease. Recombinant human alpha-N-acetylglucosaminidase (rhNAGLU) was prepared from secretions of Lec1 mutant Chinese hamster ovary cells. The enzyme, which has only unphosphorylated high-mannose carbohydrate chains, was endocytosed by mouse peritoneal macrophages via mannose receptors, with half-maximal uptake at ca. 10(-7) M. When administered intravenously to 3 month-old mice, rhNAGLU was taken up avidly by liver and spleen but marginally if at all by thymus, lung, kidney, heart, and brain (in order of diminishing uptake). The half-life of the enzyme was 2.5 days in liver and spleen. Immunohistochemistry and electron microscopy showed that only macrophages were involved in enzyme uptake and correction in these two organs, yet the storage of glycosaminoglycan was reduced to almost normal levels. The results show that the macrophage-targeted rhNAGLU can substantially reduce the body burden of glycosaminoglycan storage in the mouse model of Sanfilippo syndrome III B. 相似文献
6.
M. Shohat V. Herman S. Melmed N. Neufeld R. Schreck S. Pulst J. M. Graham D. L. Rimoin J. R. Korenberg 《American journal of medical genetics. Part A》1991,39(1):56-63
Using a molecular analysis of the DNA from a patient with a deletion of chromosome 20 [46,XX,del(20)(p11.23)], we have excluded the growth hormone-releasing hormone (GHRH) gene from the region 20p11.23→pter. The patient had minor facial anomalies, Rieger eye anomaly, a congenital heart defect, severe failure to thrive, and a neurosecretory problem in growth hormone (GH) secretion. Since the GHRH gene was previously mapped to chromosome 20, we used molecular genetic methods to determine whether the growth abnormalities were due to the deletion of this gene. DNAs of the patient and 2 normal control subjects were analyzed by quantitative Southern blotting using a DNA probe for the GHRH gene and 2 reference DNA probes mapping to chromosome 21. The GHRH gene was found to be present in 2 copies in the patient. This indicates that the gene for GHRH maps to the region outside the patient's deletion, in 20p11.23→qter. Furthermore, our results suggest that genes other than GHRH on 20p are important for developmental steps leading to normal neurosecretory function of GH and may also be involved in generating Rieger eye anomaly. Finally, GH deficiency and Rieger eye anomaly should be sought in other patients with deletions of 20p. 相似文献
7.
There is a sequence of Stereotypie metabolic changes in rats subjected to inflammation or infection. In each stress, rats respond with increases in body temperature and plasma insulin and with decreases in plasma zinc, ketone bodies, and free fatty acids. The data suggest that infection or inflammation causes an activation of phagocytic cells and also that leukocytic endogenous mediator, when injected into rats, causes some of the same alterations. Rats doubly vagotomized respond to infection in the same fashion as intact rats.In conducting the research described in this report, the investigators adhered to the Guide for the Care and Use of Laboratory Animals, as promulgated by the Committee on Care and Use of Laboratory Animals of the Institute of Laboratory Animal Resources, National Research Council. The facilities are fully accredited by the American Association for Accreditation of Laboratory Animal Care.The views of the authors do not purport to reflect the positions of the Department of the Army or the Department of Defense. 相似文献
8.
Ohne Zusammenfassung 相似文献
9.
M Shohat V Herman S Melmed N Neufeld R Schreck S Pulst J M Graham D L Rimoin J R Korenberg 《American journal of medical genetics》1991,39(1):56-63
Using a molecular analysis of the DNA from a patient with a deletion of chromosome 20 [46,XX,del(20)(p 11.23)], we have excluded the growth hormone-releasing hormone (GHRH) gene from the region 20p11.23----pter. The patient had minor facial anomalies. Rieger eye anomaly, a congenital heart defect, severe failure to thrive, and a neurosecretory problem in growth hormone (GH) secretion. Since the GHRH gene was previously mapped to chromosome 20, we used molecular genetic methods to determine whether the growth abnormalities were due to the deletion of this gene. DNAs of the patient and 2 normal control subjects were analyzed by quantitative Southern blotting using a DNA probe for the GHRH gene and 2 reference DNA probes mapping to chromosome 21. The GHRH gene was found to be present in 2 copies in the patient. This indicates that the gene for GHRH maps to the region outside the patient's deletion, in 20p11.23----qter. Furthermore, our results suggest that genes other than GHRH on 20p are important for developmental steps leading to normal neurosecretory function of GH and may also be involved in generating Rieger eye anomaly. Finally, GH deficiency and Rieger eye anomaly should be sought in other patients with deletions of 20p. 相似文献
10.
Antiviral activity of natural and recombinant human leukocyte interferons in tobacco protoplasts 总被引:1,自引:0,他引:1
Several purified species of human leukocyte interferon, including recombinant interferons, inhibit the multiplication of tobacco mosaic virus (TMV) in tobacco protoplasts derived from various cultivars. Viral RNA accumulation was determined by dot-blot hybridization to specific cDNA probes, and virus antigen was determined serologically. Interferon apparently inhibited both TMV-RNA replication and its expression into coat protein. However, these effects were of limited duration. Maximum effect was obtained when interferon was applied to the cells either prior to inoculation or within the first hour after inoculation. Antibodies to interferon abolished its antiviral activity in protoplasts. Tobacco protoplasts were about 1000 times more responsive to interferon than the reference animal viral-cell system and showed an "antiviral state" at a ratio of 1 molecule of interferon per cell. 相似文献