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1.
Ann Oncol ; 34(3): 275-288, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36526124

RESUMO

BACKGROUND: KEAP1 mutations have been associated with reduced survival in lung adenocarcinoma (LUAD) patients treated with immune checkpoint inhibitors (ICIs), particularly in the presence of STK11/KRAS alterations. We hypothesized that, beyond co-occurring genomic events, clonality prediction may help identify deleterious KEAP1 mutations and their counterparts with retained sensitivity to ICIs. PATIENTS AND METHODS: Beta-binomial modelling of sequencing read counts was used to infer KEAP1 clonal inactivation by combined somatic mutation and loss of heterozygosity (KEAP1 C-LOH) versus partial inactivation [KEAP1 clonal diploid-subclonal (KEAP1 CD-SC)] in the Memorial Sloan Kettering Cancer Center (MSK) MetTropism cohort (N = 2550). Clonality/LOH prediction was compared to a streamlined clinical classifier that relies on variant allele frequencies (VAFs) and tumor purity (TP) (VAF/TP ratio). The impact of this classification on survival outcomes was tested in two independent cohorts of LUAD patients treated with immunotherapy (MSK/Rome N = 237; DFCI N = 461). Immune-related features were studied by exploiting RNA-sequencing data (TCGA) and multiplexed immunofluorescence (DFCI mIF cohort). RESULTS: Clonality/LOH inference in the MSK MetTropism cohort overlapped with a clinical classification model defined by the VAF/TP ratio. In the ICI-treated MSK/Rome discovery cohort, predicted KEAP1 C-LOH mutations were associated with shorter progression-free survival (PFS) and overall survival (OS) compared to KEAP1 wild-type cases (PFS log-rank P = 0.001; OS log-rank P < 0.001). Similar results were obtained in the DFCI validation cohort (PFS log-rank P = 0.006; OS log-rank P = 0.014). In both cohorts, we did not observe any significant difference in survival outcomes when comparing KEAP1 CD-SC and wild-type tumors. Immune deconvolution and multiplexed immunofluorescence revealed that KEAP1 C-LOH and KEAP1 CD-SC differed for immune-related features. CONCLUSIONS: KEAP1 C-LOH mutations are associated with an immune-excluded phenotype and worse clinical outcomes among advanced LUAD patients treated with ICIs. By contrast, survival outcomes of patients whose tumors harbored KEAP1 CD-SC mutations were similar to those with KEAP1 wild-type LUADs.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Fator 2 Relacionado a NF-E2/genética , Mutação , Perda de Heterozigosidade , Imunoterapia
2.
J Cell Biol ; 147(4): 857-68, 1999 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-10562286

RESUMO

The role of the centrosomes in microtubule nucleation remains largely unknown at the molecular level. gamma-Tubulin and the two associated proteins h103p (hGCP2) and h104p (hGCP3) are essential. These proteins are also present in soluble complexes containing additional polypeptides. Partial sequencing of a 76- kD polypeptide band from these complexes allowed the isolation of a cDNA encoding for a new protein (h76p = hGCP4) expressed ubiquitously in mammalian tissues. Orthologues of h76p have been characterized in Drosophila and in the higher plant Medicago. Several pieces of evidence indicate that h76p is involved in microtubule nucleation. (1) h76p is localized at the centrosome as demonstrated by immunofluorescence. (2) h76p and gamma-tubulin are associated in the gamma-tubulin complexes. (3) gamma-tubulin complexes containing h76p bind to microtubules. (4) h76p is recruited to the spindle poles and to Xenopus sperm basal bodies. (5) h76p is necessary for aster nucleation by sperm basal bodies and recombinant h76p partially replaces endogenous 76p in oocyte extracts. Surprisingly, h76p shares partial sequence identity with human centrosomal proteins h103p and h104p, suggesting a common protein core. Hence, human gamma-tubulin appears associated with at least three evolutionary related centrosomal proteins, raising new questions about their functions at the molecular level.


Assuntos
Centrossomo/fisiologia , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/fisiologia , Tubulina (Proteína)/química , Sequência de Aminoácidos , Animais , Encéfalo/metabolismo , Células COS , Centrossomo/ultraestrutura , DNA Complementar , Drosophila , Humanos , Medicago sativa , Proteínas Associadas aos Microtúbulos/química , Microtúbulos/ultraestrutura , Dados de Sequência Molecular , Fases de Leitura Aberta , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Ovinos , Suínos , Transfecção
3.
Eur J Cell Biol ; 78(8): 549-60, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10494861

RESUMO

In mammalian cells the centrosome or diplosome is defined by the two parental centrioles observed in electron microscopy and by the pericentriolar material immunostained with several antibodies directed against various centrosomal proteins (gamma-tubulin, pericentrin, centrin and centractin). Partial destabilization of the microtubule cytoskeleton by microtubule-disassembling substances induced a splitting and a slow migration of the two diplosome units to opposite nuclear sides during most of the interphase in several mammalian cell lines. These units relocated close together following drug removal, while microtubule stabilization by nM taxol concentrations inhibited this process. Cytochalasin slowed down diplosome splitting but did not affect its relocation after colcemid washing. These results account for the apparently opposite effects induced by microtubule poisons on centriole separation. Moreover, they provide new information concerning the centrosome cycle and stability. First, the centrosome is formed by two units, distinguished only by the number of attached stable microtubules, but not by pericentrin, gamma-tubulin, centrin and centractin and their potency to nucleate microtubules. Second, the centrosomal units are independent during most of the interphase. Third, according to the cell type, these centrosomal units are localized in close proximity because they are either linked or maintained close together by the normal dynamics of the microtubule cytoskeleton. Finally, the relocalization of the centrosomal units with their centrioles in cells possessing one or two centrosomes suggests that their relative position results from the overall tensional forces involving at least partially the microtubule arrays nucleated by each of these entities.


Assuntos
Centrossomo/fisiologia , Interfase/fisiologia , Microtúbulos/química , Animais , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular/citologia , Centrossomo/efeitos dos fármacos , Centrossomo/ultraestrutura , Cricetinae , Citoesqueleto/química , Citoesqueleto/ultraestrutura , Demecolcina/farmacologia , Relação Dose-Resposta a Droga , Humanos , Interfase/efeitos dos fármacos , Microtúbulos/ultraestrutura , Paclitaxel/farmacologia , Ratos , Tubulina (Proteína)/metabolismo , Células Tumorais Cultivadas/citologia , Xenopus
4.
Eur J Cell Biol ; 80(10): 643-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11713868

RESUMO

The functional significance of distinct gamma-tubulins in several unrelated eukaryotes remains an enigma due to the difficulties to investigate this question experimentally. Using specific nucleotidic and immunological probes, we have demonstrated that the two divergent Drosophila gamma-tubulins, gamma-tub23C and gamma-tub37CD, are expressed in cultured cells. Gamma-tub37CD is constantly detected at the centrosome and absent in the mitotic spindle, while gamma-tub23C is extensively recruited to the centrosome during mitosis and relocalizes in the mitotic spindle. The two gamma-tubulins exhibit distinct biochemical properties. Gamma-tub23C is present in the soluble gamma-tubulin small complexes (10S) and gamma-tubulin big complexes (35S) and is loosely associated to the cytoskeleton. In contrast, gamma-tub37CD is undetectable in the soluble fraction and exhibits a tight binding to the centrosome. Syncytial embryos also contain the two gamma-tubulin isotypes, which are differentially recruited at the centrosome. Gamma-tub23C is present in the 10S soluble complexes only, while y-tub37CD is contained in the two soluble complexes and is recruited at the centrosome where it exhibits an heterogeneous binding. These results demonstrated an heterogeneity of the two Drosophila gamma-tubulin isotypes both in the cytoskeletal and the soluble fractions. They suggest the direct implication of the 35S complex in the centrosomal recruitment of gamma-tubulin and a conditional functional redundancy between the two gamma-tubulins.


Assuntos
Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Animais , Células Cultivadas , Centrossomo/metabolismo , Drosophila melanogaster , Embrião não Mamífero , Expressão Gênica/fisiologia , Interfase/fisiologia , Isomerismo , Metáfase/fisiologia , Microtúbulos/química , Microtúbulos/metabolismo , Solubilidade , Tubulina (Proteína)/química
5.
FEBS Lett ; 363(1-2): 145-50, 1995 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-7729536

RESUMO

The cks proteins (for cdc2 kinase subunit) are essential cell cycle regulators. They interact strongly with the mitotic cdc2 kinase, but the mechanism and the biological function of this association still await understanding. The oligomerization state in solution of two members of this ubiquitous protein family, the suc1 gene product from the fission yeast and the newly cloned cksphy gene product from the myxomycete Physarum, was investigated by small-angle X-ray scattering (SAXS) and biochemical methods. We found that the major molecular species are monodispersed monomeric proteins. Minor amounts of dimeric suc1 proteins were also found, but no equilibrium between the two forms was observed and surprisingly, the hexameric assemblies observed in the crystal structure of the human ckshs2 homolog were not detected. These apparent discrepancies between proteins that display cross-complementation address the question of the control of the cks oligomerization process and its link to the biological function.


Assuntos
Proteína Quinase CDC2/química , Proteínas de Ciclo Celular/química , Proteínas Fúngicas/química , Physarum/química , Proteínas de Protozoários , Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces/química , Sequência de Aminoácidos , Animais , Proteínas de Ciclo Celular/genética , Cromatografia em Gel , Reagentes de Ligações Cruzadas , Substâncias Macromoleculares , Dados de Sequência Molecular , Peso Molecular , Proteínas Recombinantes/química , Espalhamento de Radiação , Raios X
6.
Minerva Med ; 74(28-29): 1771-82, 1983 Jul 14.
Artigo em Italiano | MEDLINE | ID: mdl-6866309

RESUMO

Research on healthy and diseased subjects and laboratory animals have shown that Levissima oligomineral water: a) has no unpleasant or harmful subjective and/or objective side-effects even when taken at high doses for long periods. b) Encourages diuresis. Comparison with saline solution of the same osmolality showed: 1) mean increase in diuresis: 16%; 2) more rapid elimination of water; 3) significant increase in free water clearance; 4) no change in the stock of electrolytes during protracted administration. c) Influences purine exchange: 1) by increasing uric acid clearance (same comparison); 2) by reducing the hyperuricaemising effect of a rapid i.v. fructose load; 3) by opposing hyperuricaemia due to depression of mechanisms responsible for the increase of uric acid owing to enhancement of serum lactic acid after the administration of alcohol. d) Results in a characteristic change in certain coagulation parameters when compared with saline solution and tap water. It is suggested that this method be used to recognise the persistence over time of the biological activities of bottled mineral waters.


Assuntos
Diurese , Águas Minerais/efeitos adversos , Equilíbrio Hidroeletrolítico , Coagulação Sanguínea , Humanos , Purinas/metabolismo , Ácido Úrico/metabolismo
7.
J Sports Med Phys Fitness ; 30(4): 441-9, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2079852

RESUMO

The authors list the principal metabolic consequences of fatigue in athletes with special reference to alterations of fluid-electrolyte balance, acid-base balance, macroelements and trace elements. They then go on to stress the role which mineral waters, especially the bicarbonate ones, can play in the compensation of these disorders thus preventing or curing the fatigue syndrome in athletes.


Assuntos
Fadiga/dietoterapia , Águas Minerais , Esforço Físico/fisiologia , Esportes , Bicarbonatos , Água Corporal/metabolismo , Eletrólitos/metabolismo , Humanos
8.
Clin Ter ; 143(2): 131-6, 1993 Aug.
Artigo em Italiano | MEDLINE | ID: mdl-8222543

RESUMO

Bicarbonate-calcic water Ferrarelle has been administered both in the fasting state and during meals to patients suffering from gastro-esophageal reflux disease submitted to computerized pHmetry. Marked and lasting increase of esophageal and gastric pH was observed with significant differences from the effect of tap water. In addition, patients reported improvement of heart burn and acidity after the administration of the bicarbonate-calcic water. The alkalizing effect of the mineral water employed is therefore fully confirmed.


Assuntos
Bicarbonatos/uso terapêutico , Refluxo Gastroesofágico/terapia , Águas Minerais , Álcalis/uso terapêutico , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino
9.
Clin Ter ; 131(5): 321-30, 1989 Dec 15.
Artigo em Italiano | MEDLINE | ID: mdl-2532586

RESUMO

The spa treatment most widely used in the management of renal calculosis is the drinking of a certain amount of mineral water under certain predetermined conditions of temperature, time and rhythm. These treatments are always indicated unless there are obstacles to the passage of urine or general contraindications. Chances for success are increased if the diagnosis is exact and the stone has been located. The results obtained by various authors are reported and their statistical validity is discussed. Favorable effects consist in: increased diuresis with urine dilution and correspondingly reduced concentration of lithogenic salts and hence supersaturation of urine; reduced concentration of microorganisms; changes in the physiological condition of the renal medulla; changes in inhibitors of crystallization, in urinary pH; mechanical effect on the urinary passages; increased ureter motility; expulsion of small stones and sand; preventive action on recurrences after surgery and after extra-corporeal shock-wave treatment, percutaneous therapy and uretero-nephroscopy.


Assuntos
Cálculos Renais/terapia , Águas Minerais , Diurese , Feminino , Humanos , Cálculos Renais/fisiopatologia , Cálculos Renais/prevenção & controle , Masculino , Fatores de Tempo
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