Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 265
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Oncologist ; 28(6): e478-e486, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37027520

RESUMO

Ovarian cancer is the second most common gynecologic cancer in the US and ranks among the top 10 causes of female cancer-related deaths. Platinum-resistant disease carries a particularly poor prognosis and leaves patients with limited remaining therapeutic options. Patients with platinum-resistant disease have significantly lower response rates to additional chemotherapy, with estimates as low as 10%-25%. We hypothesize that in patients with platinum-resistant ovarian cancer, treatment with immunotherapy followed by cytotoxic chemotherapy with antiangiogenic therapy results in prolonged survival without compromising quality of life. Our experience of 3 patients with recurrent, metastatic platinum-resistant ovarian cancer treated with immunotherapy followed by anti-angiogenic treatment plus chemotherapy resulted in progression-free survival durations significantly above previously published averages. Further studies evaluating the role of immunotherapy followed by chemotherapy in combination with drugs targeting angiogenesis are needed and may provide a long-sought after breakthrough for advancing survival in platinum-resistant ovarian cancer.


Assuntos
Neoplasias Ovarianas , Qualidade de Vida , Feminino , Humanos , Resistencia a Medicamentos Antineoplásicos , Recidiva Local de Neoplasia/patologia , Neoplasias Ovarianas/tratamento farmacológico , Carcinoma Epitelial do Ovário/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Imunoterapia
2.
Amino Acids ; 55(12): 1803-1817, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37389730

RESUMO

In the combat of treating cancer recent therapeutic approaches are focused towards enzymatic targets as they occupy a pivotal participation in the cascade of oncogenesis and malignancy. There are several enzymes that modulate the epigenetic pathways and chromatin structure related to cancer mutation. Among several epigenetic mechanisms such as methylation, phosphorylation, and sumoylation, acetylation status of histones is crucial and is governed by counteracting enzymes like histone acetyl transferase (HAT) and histone deacetylases (HDAC) which have contradictory effects on the histone acetylation. HDAC inhibition induces chromatin relaxation which forms euchromatin and thereby initiates the expression of certain transcription factors attributed with apoptosis, which are mostly correlated with the expression of the p21 gene and acetylation of H3 and H4 histones. Most of the synthetic and natural HDAC inhibitors elicit antineoplastic effect through activation of various apoptotic pathways and promoting cell cycle arrest at various phases. Due to their promising chemo preventive action and low cytotoxicity against normal host cells, bioactive substances like flavonoids, alkaloids, and polyphenolic compounds from plants have recently gained importance. Even though all bioactive compounds mentioned have an HDAC inhibitory action, some of them have a direct effect and others enhance the effects of the standard well known HDAC inhibitors. In this review, the action of plant derived compounds against histone deacetylases in a variety of in vitro cancer cell lines and in vivo animal models are articulated.


Assuntos
Antineoplásicos , Neoplasias , Animais , Histonas/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Histona Desacetilases/uso terapêutico , Inibidores de Histona Desacetilases/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Cromatina , Neoplasias/tratamento farmacológico , Neoplasias/genética , Compostos Fitoquímicos , Acetilação
3.
Curr Genomics ; 24(6): 354-367, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38327650

RESUMO

Background: The brown planthopper (BPH) is a monophagous sap-sucking insect pest of rice that is responsible for massive yield loss. BPH populations, even when genetically homogenous, can display a vast range of phenotypes, and the development of effective pest-management strategies requires a good understanding of what generates this phenotypic variation. One potential source could be epigenetic differences. Methods: With this premise, we explored epigenetic diversity, structure and differentiation in field populations of BPH collected across the rice-growing seasons over a period of two consecutive years. Using a modified methylation-sensitive restriction assay (MSRA) and CpG island amplification-representational difference analysis, site-specific cytosine methylation of five stress-responsive genes (CYP6AY1, CYP6ER1, Carboxylesterase, Endoglucanase, Tf2-transposon) was estimated, for identifying methylation-based epiallelic markers and epigenetic variation across BPH populations. Results: Using a cost-effective and rapid protocol, our study, for the first time, revealed the epigenetic component of phenotypic variations in the wild populations of BPH. Besides, results showed that morphologically indistinguishable populations of BPH can be epigenetically distinct. Conclusion: Screening field-collected BPH populations revealed the presence of previously unreported epigenetic polymorphisms and provided a platform for future studies aimed at investigating their significance for BPH. Furthermore, these findings can form the basis for understanding the contribution(s) of DNA methylation in providing phenotypic plasticity to BPH.

4.
Br J Neurosurg ; 37(2): 127-136, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35174747

RESUMO

BACKGROUND: Vestibular schwannoma is a common pathology encountered by neurosurgeons worldwide. Often vestibular schwannoma presents with obstructive hydrocephalus. Papilledema is present in 8% of the patients with vestibular schwannoma, primarily due to obstructive hydrocephalus. Hyperproteinorrhachia is believed to be responsible for papilledema in the absence of hydrocephalus in vestibular schwannoma. However, there is a paucity of literature on the mechanism of papilledema in vestibular schwannoma patients with hydrocephalus. OBJECTIVE: The aim of this study was to conduct a scoping review of scientific literature on papilledema in vestibular schwannoma patients without hydrocephalus. METHODS: Design: This was a systematic scoping review and critical appraisal. Literature Search from PubMed was done following PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) and Joanna Briggs Institute guidelines for conducting and reporting scoping reviews. RESULTS: A total of seven studies, including eight patients, were identified for inclusion in the review. The studies were heterogeneous in terms of reporting for various variables. All the included studies were case reports, with the earliest publication in 1954 and the latest publication in 2020. The mean age of the patients in the included studies was 35 years, with a minimum age of 20 years and maximum age of 64 years. Approximately 62.5% were females, and 37.5% were males in the included study. Only three studies have studied cerebrospinal fluid (CSF) proteins levels in these patients. CONCLUSIONS: There is paucity in literature and a lack of evidence to conclusively state hyperproteinorrhachia as an antecedent to the development of papilledema in vestibular schwannoma patients without hydrocephalus. Younger age and female gender are risk factors for developing papilledema in the absence of hydrocephalus in vestibular schwannoma patients. Brainstem compression due to the large size of vestibular schwannoma can still have a patent aqueduct of Sylvius and no obstruction to CSF flow. The development of papilledema in vestibular schwannoma is a complex interplay of multiple factors that must be studied comprehensively for complete understanding.


Assuntos
Hidrocefalia , Neuroma Acústico , Papiledema , Masculino , Humanos , Feminino , Adulto , Adulto Jovem , Pessoa de Meia-Idade , Neuroma Acústico/complicações , Neuroma Acústico/patologia , Papiledema/etiologia , Hidrocefalia/complicações , Hidrocefalia/patologia , Proteínas do Líquido Cefalorraquidiano , Ventrículos Cerebrais
5.
Int J Mol Sci ; 24(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37762286

RESUMO

BPH (brown planthopper) and WBPH (white backed planthopper) are significant rice pests that often co-occur as sympatric species and cause substantial yield loss. Despite their genetic similarities, different host-resistance genes confer resistance against these two hoppers. The defense mechanisms in rice against these pests are complex, and the molecular processes regulating their responses remain largely unknown. This study used specific recombinant inbred lines (RILs) derived from a cross between rice varieties RP2068-18-3-5 (BPH- and WBPH-resistant) and TN1 (BPH- and WBPH-susceptible) to investigate the mechanisms of interaction between these planthoppers and their rice hosts. WBPH and BPH were allowed to feed on specific RILs, and RNA-Seq was carried out on WBPH insects. Transcriptome profiling and qRT-PCR results revealed differential expression of genes involved in detoxification, digestion, transportation, cuticle formation, splicing, and RNA processing. A higher expression of sugar transporters was observed in both hoppers feeding on rice with resistance against either hopper. This is the first comparative analysis of gene expressions in these insects fed on genetically similar hosts but with differential resistance to BPH and WBPH. These results complement our earlier findings on the differential gene expression of the same RILs (BPH- or WBPH-infested) utilized in this study. Moreover, identifying insect genes and pathways responsible for countering host defense would augment our understanding of BPH and WBPH interaction with their rice hosts and enable us to develop lasting strategies to control these significant pests.


Assuntos
Oryza , Oryza/genética , Genes de Insetos , Processamento Pós-Transcricional do RNA , Perfilação da Expressão Gênica , Reação em Cadeia da Polimerase
6.
Curr Genomics ; 23(2): 126-136, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-36778977

RESUMO

Background: The virulence of phytophagous insects is predominantly determined by their ability to evade or suppress host defense for their survival. The rice gall midge (GM, Orseolia oryzae), a monophagous pest of rice, elicits a host defense similar to the one elicited upon pathogen attack. This could be due to the GM feeding behaviour, wherein the GM endosymbionts are transferred to the host plant via oral secretions, and as a result, the host mounts an appropriate defense response(s) (i.e., up-regulation of the salicylic acid pathway) against these endosymbionts. Methods: The current study aimed to analyze the microbiome present at the feeding site of GM maggots to determine the exchange of bacterial species between GM and its host and to elucidate their role in rice-GM interaction using a next-generation sequencing approach. Results: Our results revealed differential representation of the phylum Proteobacteria in the GM-infested and -uninfested rice tissues. Furthermore, analysis of the species diversity of Pseudomonas and Wolbachia supergroups at the feeding sites indicated the exchange of bacterial species between GM and its host upon infestation. Conclusion: As rice-GM microbial associations remain relatively unstudied, these findings not only add to our current understanding of microbe-assisted insect-plant interactions but also provide valuable insights into how these bacteria drive insect-plant coevolution. Moreover, to the best of our knowledge, this is the first report analyzing the microbiome of a host plant (rice) at the feeding site of its insect pest (GM).

7.
Exp Parasitol ; 239: 108304, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35690094

RESUMO

Chemical acaricides are widely used for the effective control of ticks in India. The synthetic pyrethroids, are one of the most popular chemical acaricides with selective neurotoxic potential. Flumethrin is a type II synthetic pyrethroid used extensively in veterinary practice in India. The present study was undertaken to evaluate the cytotoxic effects of flumethrin on the engorged females of Rhipicephalus annulatus using entomological parameters, histology, electron microscopy and relative quantification of receptors of dopamine and GABAB mRNAs. Adult immersion test (AIT) using flumethrin (100 ppm), revealed twenty per cent mortality of ticks, hundred per cent inhibition of fecundity and complete blocking of hatching of the laid eggs. Microscopic analysis of the structure of the ovaries after 24 h of treatment with flumethrin (90 ppm) revealed changes, viz., reduction in size with the presence of amorphous material inside stage I oocytes, wrinkled boundary and chromatin fragmentation of nucleus of stage II oocytes, vacuoles around the germinal vesicle, thickening of the nuclear membrane and chromatin clumping of stage III oocytes and reduction in size and shape of mature stage IV and V oocytes. Also, a large number of vacuoles were observed throughout the pedicel cell region of stage II and III oocytes. Ultrastructurally, irregular nuclear membrane, swelling as well as crystolysis of mitochondria and detachment of external and internal layers of the basal lamina of oocytes were the major structural alterations confirming direct damaging effects of flumethrin on the germinative cells. The relative quantification of the expression of dopamine D1, dopamine D2 and GABAB receptors by quantitative real-time PCR (qRT PCR), revealed the upregulation of dopamine D1 receptor and downregulation of receptors of dopamine D2 and GABAB in the ovary of treated ticks.


Assuntos
Acaricidas , Piretrinas , Rhipicephalus , Acaricidas/farmacologia , Animais , Cromatina , Dopamina/farmacologia , Feminino , Piretrinas/farmacologia , Ácido gama-Aminobutírico/farmacologia
8.
Genomics ; 113(6): 4214-4226, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34774681

RESUMO

Transposable elements (TEs) exhibit vast diversity across insect orders and are one of the major factors driving insect evolution and speciation. Presence of TEs can be both beneficial and deleterious to their host. While it is well-established that TEs impact life-history traits, adaptations and survivability of insects under hostile environments, the influence of the ecological niche on TE-landscape remains unclear. Here, we analysed the dynamics of Tf2 retrotransposons in the brown planthopper (BPH), under environmental fluctuations. BPH, a major pest of rice, is found in almost all rice-growing ecosystems. We believe genome plasticity, attributed to TEs, has allowed BPH to adapt and colonise novel ecological niches. Our study revealed bimodal age-distribution for Tf2 elements in BPH, indicating the occurrence of two major transpositional events in its evolutionary history and their contribution in shaping BPH genome. While TEs can provide genome flexibility and facilitate adaptations, they impose massive load on the genome. Hence, we investigated the involvement of methylation in modulating transposition in BPH. We performed comparative analyses of the methylation patterns of Tf2 elements in BPH feeding on resistant- and susceptible-rice varieties, and also under pesticide stress, across different life-stages. Results confirmed that methylation, particularly in non-CG context, is involved in TE regulation and dynamics under stress. Furthermore, we observed differential methylation for BPH adults and nymphs, emphasising the importance of screening juvenile life-stages in understanding adaptive-stress-responses in insects. Collectively, this study enhances our understanding of the role of transposons in influencing the evolutionary trajectory and survival strategies of BPH across generations.


Assuntos
Hemípteros , Oryza , Animais , Ecossistema , Hemípteros/genética , Metilação , Oryza/genética , Retroelementos
9.
Int J Mol Sci ; 23(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35955860

RESUMO

DNA methylation in insects is integral to cellular differentiation, development, gene regulation, genome integrity, and phenotypic plasticity. However, its evolutionary potential and involvement in facilitating rapid adaptations in insects are enigmatic. Moreover, our understanding of these mechanisms is limited to a few insect species, of which none are pests of crops. Hence, we studied methylation patterns in the brown planthopper (BPH), a major rice pest, under pesticide and nutritional stress, across its life stages. Moreover, as the inheritance of epigenetic changes is fundamentally essential for acclimation, adaptability, and evolution, we determined the heritability and persistence of stress-induced methylation marks in BPH across generations. Our results revealed that DNA methylation pattern(s) in BPH varies/vary with environmental cues and is/are insect life-stage specific. Further, our findings provide novel insights into the heritability of stress-induced methylation marks in BPH. However, it was observed that, though heritable, these marks eventually fade in the absence of the stressors, thereby suggesting the existence of fitness cost(s) associated with the maintenance of the stressed epigenotype. Furthermore, we demonstrate how 5-azacytidine-mediated disruption of BPH methylome influences expression levels of stress-responsive genes and, thereby, highlight demethylation/methylation as a phenomenon underlying stress resilience of BPH.


Assuntos
Hemípteros , Oryza , Animais , Aclimatação , Adaptação Fisiológica/genética , Epigenômica , Hemípteros/fisiologia , Oryza/genética
10.
Pediatr Transplant ; 25(3): e13923, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33314641

RESUMO

Malignant hyperthermia (MH) is a rare life-threatening anesthetic complication with high mortality rates. MH during adult kidney transplant has been reported previously. However, the occurrence of MH after multiple previous uneventful anesthetic exposures in a pediatric kidney transplant recipient is rare. To our knowledge, this is the first reported case of MH in a child undergoing a live donor kidney transplant. The approaches for addressing perioperative challenges and ethical dilemmas to ensure successful outcomes are described. The recipient, a 5-year-old male child, weighing 20 kg, with a history of multiple previous uneventful anesthetic exposures, underwent live donor kidney transplant for end-stage renal disease (ESRD). Post-reperfusion he developed fulminant MH with rapidly progressing hyperthermia, hypercarbia, tachycardia, and muscle rigidity, which in addition to complicating the medical management raised several ethical issues as well. MH was successfully managed with dantrolene and other supportive measures. Judicious use of inotropes and fluids helped maintain stable hemodynamics and graft perfusion. Management of MH is complicated in a pediatric patient with ESRD undergoing live donor kidney transplant. Preference for non-depolarizing muscle relaxants instead of succinylcholine during endotracheal intubation can result in delayed onset of clinical manifestations. However, the metabolic complications may be more severe due to preexisting electrolyte and acid-base disturbances. Maintaining optimal graft perfusion while simultaneously combating MH can be very challenging in a child. Since the allograft is a precious commodity, critical decisions regarding the harvesting of the donor kidney need to be well thought out. Early diagnosis and prompt treatment with dantrolene are critical to preserving graft function and the recipient's life.


Assuntos
Temas Bioéticos , Cuidados Intraoperatórios/ética , Falência Renal Crônica/cirurgia , Transplante de Rim , Hipertermia Maligna/terapia , Pré-Escolar , Humanos , Masculino
11.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443355

RESUMO

Amitraz, a member of the formamidine pesticide family, commonly used for ectoparasite control, is applied as a dip or low-pressure hand spray to cattle and swine, and the neck collar on dogs. Data on amitraz were generated mainly on laboratory animals, hens, dogs, and baboons. The data on the toxicity and disposition of amitraz in animals and its residues in the milk are inadequate. Therefore, the present study was intended to analyze the disposition kinetics of amitraz and its pattern of elimination in the milk of lactating does after a single dermal application at a concentration of 0.25%. Blood at predetermined time intervals and milk twice daily were collected for eight days post application. The drug concentration was assayed by high-performance liquid chromatography (HPLC). Amitraz was detected in whole blood as early as 0.5 h, which attained a peak concentration at 12 ± 5 h, followed by a steady decline; however, detection persisted until 168 h. Amitraz was present in the blood at its 50% Cmax even after 48 h, and was still detectable after 7 days. The disposition after a single dermal application was best described non-compartmentally. The mean terminal half-life (t1/2), mean residence time (MRT), and area under the curve (AUC0-t) were 111 ± 31 h, 168 ± 39 h, and 539 ± 211 µg/mL/h, respectively. The apparent volume of distribution (Vdarea) was 92 ± 36 mL/g with an observed clearance (Cl) of 0.57 ± 0.33 mL/kg/h. Thus, the drug was well absorbed, widely distributed and slowly eliminated from the animal body. Amitraz achieved milk concentration approximating 0.2 per cent of the total dose after a single exposure and the steady-state elimination of amitraz in milk above the recommended maximum residue limit (MRL) of 0.01 mg/kg can act as a source of public health concern when applied on lactating animals.


Assuntos
Cervos , Lactação , Resíduos de Praguicidas/metabolismo , Toluidinas/metabolismo , Animais , Ácidos Cólicos , Feminino , Meia-Vida , Cinética
12.
Molecules ; 26(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34443500

RESUMO

Prostaglandins are a group of important cell-signaling molecules involved in the regulation of ovarian maturation, oocyte development, egg laying and associated behaviors in invertebrates. However, the presence of prostaglandin E2 (PGE2), the key enzymes for PGE2 biosynthesis and its interference by drugs were not investigated previously in the ovary of ticks. The present study was undertaken to assess the modulation of the PGE2-mediated pathway in the eclosion blocking effect of flumethrin and terpenoid subfraction isolated from Artemisia nilagirica in Rhipicephalus annulatus ticks. The acaricidal activities and chemical profiling of the terpenoid subfraction were performed. The localization of the cyclooxygenase1 (COX1) and prostaglandin E synthase (PGES) enzymes and the quantification of PGE2 in the ovaries of the ticks treated with methanol (control), flumethrin and terpenoid subfraction were also undertaken. In addition, the vitellogenin concentration in hemolymph was also assayed. Both flumethrin and the terpenoid subfraction of A. nilagirica elicited a concentration-dependent inhibition of fecundity and blocking of hatching of the eggs. The COX1 could not be detected in the ovaries of treated and control ticks, while there was no significant difference observed in the concentration of vitellogenin (Vg) in them. The presence of PGES in the oocytes of control ticks was confirmed while the immunoreactivities against PGES were absent in the vitellogenic oocytes of ticks treated with flumethrin and terpenoid subfraction. The levels of PGE2 were below the detection limit in the ovaries of the flumethrin-treated ticks, while it was significantly lower in the ovaries of the terpenoid subfraction-treated ticks. Hence, the prostaglandin E synthase and PGE2 were identified as very important mediators for the signaling pathway for ovarian maturation and oviposition in ticks. In addition, the key enzyme for prostaglandin biosynthesis, PGES and the receptors for PGE2 can be exploited as potential drug targets for tick control. The detection of PGES by immunohistochemistry and quantification of PGE2 by LC-MSMS can be employed as valuable tools for screening newer compounds for their eclosion blocking acaricidal effects.


Assuntos
Artemisia/química , Dinoprostona/metabolismo , Piretrinas/farmacologia , Rhipicephalus/efeitos dos fármacos , Terpenos/isolamento & purificação , Terpenos/farmacologia , Animais , Anticorpos/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hemolinfa/metabolismo , Imersão , Ovário/efeitos dos fármacos , Ovário/enzimologia , Peroxidase/metabolismo , Prostaglandina-E Sintases/metabolismo , Vitelogeninas/metabolismo
13.
N Engl J Med ; 376(25): 2415-2426, 2017 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-28636851

RESUMO

BACKGROUND: Nivolumab has been associated with longer overall survival than docetaxel among patients with previously treated non-small-cell lung cancer (NSCLC). In an open-label phase 3 trial, we compared first-line nivolumab with chemotherapy in patients with programmed death ligand 1 (PD-L1)-positive NSCLC. METHODS: We randomly assigned, in a 1:1 ratio, patients with untreated stage IV or recurrent NSCLC and a PD-L1 tumor-expression level of 1% or more to receive nivolumab (administered intravenously at a dose of 3 mg per kilogram of body weight once every 2 weeks) or platinum-based chemotherapy (administered once every 3 weeks for up to six cycles). Patients receiving chemotherapy could cross over to receive nivolumab at the time of disease progression. The primary end point was progression-free survival, as assessed by means of blinded independent central review, among patients with a PD-L1 expression level of 5% or more. RESULTS: Among the 423 patients with a PD-L1 expression level of 5% or more, the median progression-free survival was 4.2 months with nivolumab versus 5.9 months with chemotherapy (hazard ratio for disease progression or death, 1.15; 95% confidence interval [CI], 0.91 to 1.45; P=0.25), and the median overall survival was 14.4 months versus 13.2 months (hazard ratio for death, 1.02; 95% CI, 0.80 to 1.30). A total of 128 of 212 patients (60%) in the chemotherapy group received nivolumab as subsequent therapy. Treatment-related adverse events of any grade occurred in 71% of the patients who received nivolumab and in 92% of those who received chemotherapy. Treatment-related adverse events of grade 3 or 4 occurred in 18% of the patients who received nivolumab and in 51% of those who received chemotherapy. CONCLUSIONS: Nivolumab was not associated with significantly longer progression-free survival than chemotherapy among patients with previously untreated stage IV or recurrent NSCLC with a PD-L1 expression level of 5% or more. Overall survival was similar between groups. Nivolumab had a favorable safety profile, as compared with chemotherapy, with no new or unexpected safety signals. (Funded by Bristol-Myers Squibb and others; CheckMate 026 ClinicalTrials.gov number, NCT02041533 .).


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas/induzido quimicamente , Antígeno B7-H1/metabolismo , Intervalo Livre de Doença , Humanos , Neoplasias Pulmonares/induzido quimicamente
14.
Clin Gastroenterol Hepatol ; 18(12): 2717-2723.e3, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31811950

RESUMO

BACKGROUND & AIMS: Many genetic variants have been associated with colorectal cancer risk, although few have been associated with survival times of patients. Identification of genetic variants associated with survival times might improve our understanding of disease progression and aid in outcome prediction. We performed a genome-wide association study to identify variants associated with colon cancer survival time. METHODS: We performed a post hoc analysis of data from NCCTG N0147 (Alliance), a randomized phase 3 trial of patients with resected stage III colon cancer, and from NSABP C-08 (NRG), a phase 3 trial that compared therapy regimens for patients with resected stage II or III colon cancer. Genotype analyses were performed on DNA from blood samples from 4974 patients. We used Cox proportional hazards regression to evaluate the association of each single nucleotide polymorphism with times of overall survival and disease-free survival, adjusting for age at diagnosis, sex, treatment group, and principal components of genetic ancestry. We performed the analysis for studies N0147 and C-08 separately, and results were combined in a fixed-effects meta-analysis. RESULTS: A locus on chromosome 7p15.2 was significantly associated with overall survival time (P ≤ 5x10-08). The most significant variant at this locus, rs76766811 (P = 1.6x10-08), is common among African Americans (minor allele frequency, approximately 18%) but rare in European Americans (minor allele frequency <0.1%). Within strata of self-reported ancestry, this variant was associated with times of overall survival and disease-free survival in only African Americans (hazard ratio for overall survival, 2.82; 95% CI, 1.88-4.23; P = 5.0x10-07 and hazard ratio for disease-free survival, 2.27; 95% CI, 1.62-3.18; P = 1.8x10-06). CONCLUSIONS: In an analysis of data from 2 trials of patients with stage II or III colon cancer, we identified rs76766811 as a potential prognostic variant in African American patients. This finding should be confirmed in additional study populations. ClinicalTrials.gov Identifiers: NCT00096278 (NSABP C-08) and NCT00079274 (NCCTG N0147).


Assuntos
Neoplasias do Colo , Estudo de Associação Genômica Ampla , Protocolos de Quimioterapia Combinada Antineoplásica , Ensaios Clínicos Fase III como Assunto , Neoplasias do Colo/patologia , Intervalo Livre de Doença , Humanos , Estadiamento de Neoplasias , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Pituitary ; 23(5): 515-525, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32451987

RESUMO

OBJECTIVE: Implication of the tumor size on oncological and functional outcomes of craniopharyngioma is inconsistently reported. The aim of this study is to assess the postoperative outcome of giant craniopharyngiomas (> 4 cm in diameter) and to elucidate the impact of tumor size on various outcome parameters and survival. MATERIAL AND METHODS: Forty-four patients (children aged ≤ 18 years: 25; adults: 16) with giant craniopharyngioma, operated between January 2001 and December 2015, were included in this study. Various outcomes, progression-free survival (PFS) and overall survival (OS) were calculated. RESULTS: Gross total resection (GTR) was achieved in 17 (39%) and subtotal resection (STR) in 27 (61%) patients. Eleven patients (25%) received radiotherapy (RT) after STR. Postoperatively, new cranial nerve and motor deficits were noted in 12 (27%) and 9 (20%) patients, respectively. Tumor recurrence following GTR and STR without adjuvant RT was diagnosed in 3 (17%), and 5 (38%) patients, respectively. Following STR with RT, one (9%) experienced recurrence. PFS at 5-, and 10- year following GTR, STR, and STR + RT was 80.8%, 45.4%, and 90%, respectively. At 5- and 10- year, OS was 86.5%, 77.9% and 100% following GTR, STR, and STR + RT, respectively. The rate of GTR was significantly lower in patients with giant tumors (39% vs. 62%; Chi-square test, p value 0.008). Postoperatively, neurological deficit (20%), hypopituitarism (95%) and hypothalamic dysfunction (26%) were significantly higher for giant craniopharyngiomas. Hazards of recurrence were not significant between giant and non-giant tumors (hazard ratio 1.86; 95% CI 0.94-3.68; p 0.07). There was no significant difference in OS between the patients with giant and non-giant tumors (log-rank test 2.1; p value 0.14). CONCLUSION: Tumor size should be considered as an important predictor of the postoperative functional outcome. Although the rate of GTR is less than that of small tumors, the recurrence rate, progression-free survival, and overall survival of the patients with giant tumor are comparable to non-giant tumors.


Assuntos
Craniofaringioma/patologia , Craniofaringioma/cirurgia , Craniofaringioma/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Hipopituitarismo/mortalidade , Hipopituitarismo/patologia , Hipopituitarismo/cirurgia , Doenças Hipotalâmicas/mortalidade , Doenças Hipotalâmicas/patologia , Doenças Hipotalâmicas/cirurgia , Masculino , Período Pós-Operatório , Intervalo Livre de Progressão , Estudos Retrospectivos , Resultado do Tratamento
16.
Planta Med ; 86(18): 1335-1344, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32663894

RESUMO

Since time immemorial, human beings have used various parts of plants in either prevention or treatment of ailments. Plants are rich sources of secondary metabolites such as alkaloids, steroids, terpenoids, flavonoids, and phenolic compounds with a high structural diversity. Many plants/herbs with specific biological activities such as antitumor, antioxidant, anti-inflammatory, antifungal, sedative, and acaricidal activity have been reported. Artemisia nilagirica (C. B. Clarke) Pamp. (Compositae) is a plant traditionally used for insect control in the southern part of India. Previous studies have demonstrated the activity of Artemisia species against pests. The present study thus evaluates the acaricidal activity of crude ethanolic extract of A. nilagirica leaves and its fractions against Rhipicephalus (Boophilus) annulatus. Ticks are ectoparasites that transmit several protozoal, viral, and rickettsial diseases. In south India, R. (B.) annulatus is the commonly observed tick species. Control of these acarine parasites that adversely affect milk and meat production is a tough task. Chemical acaricides such as organophosphates, synthetic pyrethroids, amitraz, and ivermectin are commonly used in tick control. The high cost, environmental hazards, and development of acaricidal resistance are some of the drawbacks of these chemical acaricides. Plant-based formulations are one of the promising approaches for the control of ectoparasites. Previously, extracts from various medicinal/aromatic plants were reported for acaricidal activity from our laboratory, such as Tetrastigma leucostaphylum (Dennst.) Alston, Chassalia curviflora (Wall.) Thwaites, Jatropha curcas L., and Ageratum conyzoides Hieron. Biochemical quantification, fluorescence analysis, and primary phytochemical analysis are already reported for the ethanolic extract and its fractions of areal parts of A. nilagirica. Phytochemical characterization of ethanolic extract of A. nilagirica from Kerala, India was shown to have the presence of terpenoids, flavonoids, steroids, saponins, fixed oils and fats, tannins, and glycosides.


Assuntos
Acaricidas , Artemisia , Rhipicephalus , Acaricidas/farmacologia , Animais , Índia , Extratos Vegetais/farmacologia , Folhas de Planta
17.
Neurosurg Rev ; 43(1): 169-175, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30171501

RESUMO

Spinal hemangioblastomas constitute 1.6-5.8% of all spinal cord tumors. Microsurgical excision of these tumors is challenging. The purpose of this study is to analyze the neurological improvement and long-term functional outcome of spinal hemangioblastomas. This retrospective study included 15 patients who underwent surgery for intramedullary spinal hemangioblastoma at the Department of Neurosurgery of Sri Chitra Tirunal Institute for Medical Sciences and Technology from January 2001 to June 2014. Eight patients (53%) were diagnosed to have von Hippel-Lindau (vHL) disease. Eight (53%) of them were females, and seven were males (47%). Mean age was 33.8 years (16-55 years). Duration of illness ranged from 2 weeks to 4 years, and average duration was 10.5 months. Most common symptom was motor weakness followed by sensory disturbances, pain, and bladder incontinence. Six (85.7%) sporadic spinal hemangioblastomas were in McCormick grade I; whereas, 7 (87.5%) of vHL spinal hemangioblastomas were in grade II or above. In the immediate postoperative period, three patients noticed improvement in their motor weakness. Six patients (40%) experienced deterioration of preoperative neurological status in the immediate postoperative period. Three of them were sporadic tumors, and others had vHL syndrome. Favorable long-term outcome was achieved in 80% of cases. Though neurological deterioration is common after surgical resection of spinal hemangioblastomas, majority of them are reversible. Long-term functional outcome is favorable with minimal postoperative morbidities. Both sporadic- and vHL-associated tumors share common clinical and radiological features, and neurological outcome is equally good in both.


Assuntos
Hemangioblastoma/diagnóstico , Hemangioblastoma/cirurgia , Neoplasias da Medula Espinal/diagnóstico , Neoplasias da Medula Espinal/cirurgia , Adolescente , Adulto , Feminino , Seguimentos , Hemangioblastoma/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Prognóstico , Estudos Retrospectivos , Neoplasias da Medula Espinal/complicações , Resultado do Tratamento , Adulto Jovem , Doença de von Hippel-Lindau/complicações , Doença de von Hippel-Lindau/diagnóstico , Doença de von Hippel-Lindau/cirurgia
18.
Oncologist ; 24(1): e49-e52, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30104290

RESUMO

A substantial fraction of patients demonstrate resistance to immune checkpoint inhibitors, which limits their use. Use of radiation concurrently with checkpoint inhibitors has been shown to boost immune responsiveness, resulting in significant tumor regression in patients with metastatic melanoma. However, it is unknown whether radiation could play a role in reversing the inherent resistance to checkpoint inhibition in certain tumor types. Most trials testing this concurrent approach exclude such modestly responsive tumors and pursue checkpoint inhibition using anti-cytotoxic T-lymphocyte-associated protein 4 antibody (anti-CTLA-4, ipilimumab). The efficacy of anti-programmed-death-1 (anti-PD-1) therapy when used concurrently with radiation is less known but remains an attractive option due to less autoimmune toxicity compared with CTLA-4 inhibition. In this first reported experience, we have safely and effectively combined anti-PD-1 therapy (nivolumab) concurrently with radiation to treat two patients with relapsed sarcomatoid renal carcinoma and heavily pretreated pleomorphic sarcoma. Both patients experienced a dramatic response that was durable.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Sarcoma/tratamento farmacológico , Sarcoma/radioterapia , Idoso , Anticorpos Monoclonais Humanizados/farmacologia , Diferenciação Celular , Humanos , Masculino , Sarcoma/patologia
19.
IUBMB Life ; 71(2): 244-253, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30393962

RESUMO

Sphere formation is an indicator of tumor aggressiveness independent of the tumor grade; however, its relation to progression-free survival (PFS) is less known. This study was designed to assess the neurosphere forming ability among low grade glioma (LGG) and high-grade glioma (HGG), its stem cell marker expression, and correlation to PFS. Tumor samples of 140 patients, including (LGG; n = 67) and (HGG; n = 73) were analyzed. We used sphere forming assay, immunofluorescence, and immunohistochemistry to characterize the tumors. Our study shows that, irrespective of the pathological sub type, both LGG and HGG formed neurospheres in vitro under conventional sphere forming conditions. However, the number of neurospheres formed from tumor tissues were significantly higher in HGG compared to LGG (P < 0.0001). Different grades of glioma were further characterized for the expression of stem cell marker proteins and lineage markers. When neurospheres were analyzed, CD133 positive cells were identified in addition to CD15 and nestin positive cells in both LGG and HGG. When these neurospheres were subjected to differentiation, cells positive for GFAP and ß-tubulin III were observed. Expression of stem cell markers and ß-tubulin III were prominent in HGG compared to LGG, whereas GFAP expression was higher in LGG than in HGG. Kaplan-Meier survival analysis demonstrated that neurosphere forming ability was significantly associated with shorter PFS (P < 0.05) in both LGG and HGG. Our results supports earlier studies that neurosphere formation may serve as a definitive indicator of stem cell population within the tumor and thus a better predictor of PFS than the tumor grades alone. © 2018 IUBMB Life, 71(1):244-253, 2019.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Células-Tronco Neoplásicas/metabolismo , Neurônios/metabolismo , Esferoides Celulares/metabolismo , Antígeno AC133/genética , Antígeno AC133/metabolismo , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Diferenciação Celular , Criança , Pré-Escolar , Feminino , Expressão Gênica , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Glioma/genética , Glioma/mortalidade , Glioma/patologia , Humanos , Lactente , Antígenos CD15/genética , Antígenos CD15/metabolismo , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Células-Tronco Neoplásicas/patologia , Nestina/genética , Nestina/metabolismo , Neurônios/patologia , Prognóstico , Esferoides Celulares/patologia , Análise de Sobrevida , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo
20.
J Natl Compr Canc Netw ; 17(9): 1083-1087, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31487684

RESUMO

BACKGROUND: The proliferation of relationships between community health systems and academic medical centers has created a need to identify effective components of these models. This article reports on frontline physician experiences, with one such relationship established through the Memorial Sloan Kettering Cancer Center (MSK) Cancer Alliance. MSK created the Alliance with the goals of rapidly bringing the newest standards of care into community settings and increasing patient access to clinical trials in their local communities. METHODS: Alliance leadership administered a 10-question anonymous survey to physicians treating patients with cancer across the 3 Alliance member health systems: Hartford HealthCare Cancer Institute, Lehigh Valley Cancer Institute, and Miami Cancer Institute at Baptist Health South Florida. The purpose of the survey was to identify opportunities to improve physician engagement. RESULTS: There were 103 clinician respondents across Alliance members, of which 87 reported participation in a disease management team and were included in the final analysis. Most respondents reported high value from Alliance activities, such as attending MSK tumor boards (94%) and lecture series (96%), among those who reported them applicable. Across all respondents, most reported satisfaction with engagement opportunities, such as MSK physician participation in their institution's meetings (76%). When asked where they would like to see increased engagement, the most commonly reported response was for more lecture series (45%). Most respondents (88%) reported that the Alliance led to practice change, either for themselves or for other clinicians at their institution. Many attributed this practice change to MSK disease-specific process measures. CONCLUSIONS: The activities most valued by community physicians were heavily physician relationship-based. The encouraging experience of the MSK Cancer Alliance suggests that activities involving physician investment may be effective for promoting practice change in the context of cross-institution relationships. Future research is needed in this area.


Assuntos
Serviços de Saúde Comunitária , Redes Comunitárias , Oncologia , Oncologistas , Médicos de Atenção Primária , Humanos , Oncologia/métodos , Avaliação de Resultados em Cuidados de Saúde , Melhoria de Qualidade , Qualidade da Assistência à Saúde
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA