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1.
J Clin Oncol ; 41(19): 3461-3468, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37379691

RESUMO

PURPOSE: Three agents with differing mechanisms of action are available for treatment of advanced colorectal cancer: fluorouracil, irinotecan, and oxaliplatin. In this study, we compared the activity and toxicity of three different two-drug combinations in patients with metastatic colorectal cancer who had not been treated previously for advanced disease. PATIENTS AND METHODS: Patients were concurrently randomly assigned to receive irinotecan and bolus fluorouracil plus leucovorin (IFL, control combination), oxaliplatin and infused fluorouracil plus leucovorin (FOLFOX), or irinotecan and oxaliplatin (IROX). The primary end point was time to progression, with secondary end points of response rate, survival time, and toxicity. RESULTS: A total of 795 patients were randomly assigned between May 1999 and April 2001. A median time to progression of 8.7 months, response rate of 45%, and median survival time of 19.5 months were observed for FOLFOX. These results were significantly superior to those observed for IFL for all end points (6.9 months, 31%, and 15.0 months, respectively) or for IROX (6.5 months, 35%, and 17.4 months, respectively) for time to progression and response. The FOLFOX regimen had significantly lower rates of severe nausea, vomiting, diarrhea, febrile neutropenia, and dehydration. Sensory neuropathy and neutropenia were more common with the regimens containing oxaliplatin. CONCLUSION: The FOLFOX regimen of oxaliplatin and infused fluorouracil plus leucovorin was active and comparatively safe. It should be considered as a standard therapy for patients with advanced colorectal cancer.

2.
Cancer Control ; 30: 10732748231185047, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37339926

RESUMO

BACKGROUND: Previous studies have established that higher baseline quality of life (QOL) scores are associated with improved survival in patients with metastatic colorectal cancer (mCRC). We examined the relationship between overall survival (OS) and baseline QOL. PATIENTS AND METHODS: A total of 1 247 patients with mCRC participating in N9741 (comparing bolus 5-FU/LV, irinotecan [IFL] vs infusional 5-FU/leucovorin [LV]/oxaliplatin [FOLFOX] vs. irinotecan/oxaliplatin [IROX]) provided data at baseline on overall QOL using a single-item linear analogue self-assessment (LASA) 0-100 point scale. The association of OS according to clinically deficient (defined as CD-QOL, score 0-50) vs not clinically deficient (nCD-QOL, score 51-100) baseline QOL scores was tested. A multivariable analysis using Cox proportional hazards modeling was performed to adjust for the effects of multiple baseline factors. An exploratory analysis was performed evaluating OS according to baseline QOL status among patients who did or did not receive second-line therapy. RESULTS: Baseline QOL was a strong predictor of OS for the whole cohort (CD-QOL vs nCD-QOL: 11.2 months vs 18.4 months, P < .0001), and in each arm IFL 12.4 vs 15.1 months, FOLFOX 11.1 months vs 20.6 months, and IROX 8.9 months vs 18.1 months. Baseline QOL was associated with baseline performance status (PS) (P < .0001). After adjusting for PS and treatment arm, baseline QOL was still associated with OS (P = .017). CONCLUSIONS: Baseline QOL is an independent prognostic factor for OS in patients with mCRC. The demonstration that patient-assessed QOL and PS are independent prognostic indicators suggests that these assessments provide important complementary prognostic information.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Oxaliplatina/uso terapêutico , Irinotecano/uso terapêutico , Neoplasias Colorretais/patologia , Qualidade de Vida , Camptotecina , Prognóstico , Fluoruracila/uso terapêutico , Leucovorina/uso terapêutico
3.
PLoS One ; 18(5): e0285756, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37192177

RESUMO

Red raspberry (Rubus idaeus L.) is an economically valuable soft-fruit species with a relatively small (~300 Mb) but highly heterozygous diploid (2n = 2x = 14) genome. Chromosome-scale genome sequences are a vital tool in unravelling the genetic complexity controlling traits of interest in crop plants such as red raspberry, as well as for functional genomics, evolutionary studies, and pan-genomics diversity studies. In this study, we developed genome sequences of a primocane fruiting variety ('Autumn Bliss') and a floricane variety ('Malling Jewel'). The use of long-read Oxford Nanopore Technologies sequencing data yielded long read lengths that permitted well resolved genome sequences for the two cultivars to be assembled. The de novo assemblies of 'Malling Jewel' and 'Autumn Bliss' contained 79 and 136 contigs respectively, and 263.0 Mb of the 'Autumn Bliss' and 265.5 Mb of the 'Malling Jewel' assembly could be anchored unambiguously to a previously published red raspberry genome sequence of the cultivar 'Anitra'. Single copy ortholog analysis (BUSCO) revealed high levels of completeness in both genomes sequenced, with 97.4% of sequences identified in 'Autumn Bliss' and 97.7% in 'Malling Jewel'. The density of repetitive sequence contained in the 'Autumn Bliss' and 'Malling Jewel' assemblies was significantly higher than in the previously published assembly and centromeric and telomeric regions were identified in both assemblies. A total of 42,823 protein coding regions were identified in the 'Autumn Bliss' assembly, whilst 43,027 were identified in the 'Malling Jewel' assembly. These chromosome-scale genome sequences represent an excellent genomics resource for red raspberry, particularly around the highly repetitive centromeric and telomeric regions of the genome that are less complete in the previously published 'Anitra' genome sequence.


Assuntos
Nanoporos , Rubus , Rubus/genética , Genoma , Genômica , Análise de Sequência de DNA , Centrômero
4.
Theor Appl Genet ; 136(4): 74, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36952013

RESUMO

KEY MESSAGE: For genomic selection in clonally propagated crops with diploid (-like) meiotic behavior to be effective, crossing parents should be selected based on genomic predicted cross-performance unless dominance is negligible. For genomic selection (GS) in clonal breeding programs to be effective, parents should be selected based on genomic predicted cross-performance unless dominance is negligible. Genomic prediction of cross-performance enables efficient exploitation of the additive and dominance value simultaneously. Here, we compared different GS strategies for clonally propagated crops with diploid (-like) meiotic behavior, using strawberry as an example. We used stochastic simulation to evaluate six combinations of three breeding programs and two parent selection methods. The three breeding programs included (1) a breeding program that introduced GS in the first clonal stage, and (2) two variations of a two-part breeding program with one and three crossing cycles per year, respectively. The two parent selection methods were (1) parent selection based on genomic estimated breeding values (GEBVs) and (2) parent selection based on genomic predicted cross-performance (GPCP). Selection of parents based on GPCP produced faster genetic gain than selection of parents based on GEBVs because it reduced inbreeding when the dominance degree increased. The two-part breeding programs with one and three crossing cycles per year using GPCP always produced the most genetic gain unless dominance was negligible. We conclude that (1) in clonal breeding programs with GS, parents should be selected based on GPCP, and (2) a two-part breeding program with parent selection based on GPCP to rapidly drive population improvement has great potential to improve breeding clonally propagated crops.


Assuntos
Melhoramento Vegetal , Seleção Genética , Melhoramento Vegetal/métodos , Genoma , Genômica/métodos , Endogamia , Produtos Agrícolas/genética , Modelos Genéticos
5.
G3 (Bethesda) ; 13(2)2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36331334

RESUMO

Blackberries (Rubus spp.) are the fourth most economically important berry crop worldwide. Genome assemblies and annotations have been developed for Rubus species in subgenus Idaeobatus, including black raspberry (R. occidentalis), red raspberry (R. idaeus), and R. chingii, but very few genomic resources exist for blackberries and their relatives in subgenus Rubus. Here we present a chromosome-length assembly and annotation of the diploid blackberry germplasm accession "Hillquist" (R. argutus). "Hillquist" is the only known source of primocane-fruiting (annual-fruiting) in tetraploid fresh-market blackberry breeding programs and is represented in the pedigree of many important cultivars worldwide. The "Hillquist" assembly, generated using Pacific Biosciences long reads scaffolded with high-throughput chromosome conformation capture sequencing, consisted of 298 Mb, of which 270 Mb (90%) was placed on 7 chromosome-length scaffolds with an average length of 38.6 Mb. Approximately 52.8% of the genome was composed of repetitive elements. The genome sequence was highly collinear with a novel maternal haplotype-resolved linkage map of the tetraploid blackberry selection A-2551TN and genome assemblies of R. chingii and red raspberry. A total of 38,503 protein-coding genes were predicted, of which 72% were functionally annotated. Eighteen flowering gene homologs within a previously mapped locus aligning to an 11.2 Mb region on chromosome Ra02 were identified as potential candidate genes for primocane-fruiting. The utility of the "Hillquist" genome has been demonstrated here by the development of the first genotyping-by-sequencing-based linkage map of tetraploid blackberry and the identification of possible candidate genes for primocane-fruiting. This chromosome-length assembly will facilitate future studies in Rubus biology, genetics, and genomics and strengthen applied breeding programs.


Assuntos
Rubus , Rubus/genética , Tetraploidia , Melhoramento Vegetal , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Anotação de Sequência Molecular
6.
PLoS One ; 17(3): e0265096, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35294470

RESUMO

Rubus idaeus L. (red raspberry), is a perennial woody plant species of the Rosaceae family that is widely cultivated in the temperate regions of world and is thus an economically important soft fruit species. It is prized for its flavour and aroma, as well as a high content of healthful compounds such as vitamins and antioxidants. Breeding programs exist globally for red raspberry, but variety development is a long and challenging process. Genomic and molecular tools for red raspberry are valuable resources for breeding. Here, a chromosome-length genome sequence assembly and related gene predictions for the red raspberry cultivar 'Anitra' are presented, comprising PacBio long read sequencing scaffolded using Hi-C sequence data. The assembled genome sequence totalled 291.7 Mbp, with 247.5 Mbp (84.8%) incorporated into seven sequencing scaffolds with an average length of 35.4 Mbp. A total of 39,448 protein-coding genes were predicted, 75% of which were functionally annotated. The seven chromosome scaffolds were anchored to a previously published genetic linkage map with a high degree of synteny and comparisons to genomes of closely related species within the Rosoideae revealed chromosome-scale rearrangements that have occurred over relatively short evolutionary periods. A chromosome-level genomic sequence of R. idaeus will be a valuable resource for the knowledge of its genome structure and function in red raspberry and will be a useful and important resource for researchers and plant breeders.


Assuntos
Rubus , Cromossomos , Genômica , Melhoramento Vegetal , Rubus/genética , Análise de Sequência de DNA
7.
PLoS One ; 16(8): e0255139, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34339434

RESUMO

Fruit firmness and in particular the individual components of texture and moisture loss, are considered the key quality traits when describing blueberry fruit quality, and whilst these traits are genetically regulated, the mechanisms governing their control are not clearly understood. In this investigation, RNAseq was performed on fruits of two blueberry cultivars with very different storage properties, 'Bluecrop' and 'Legacy', at harvest, three weeks storage in a non-modified environment at 4 °C and after three weeks storage at 4 °C followed by three days at 21 °C, with the aim of understanding the transcriptional changes that occur during storage in cultivars with very different post-harvest fruit quality. De novo assemblies of the transcriptomes of the two cultivars were performed separately and a total of 39,335 and 41,896 unigenes for 'Bluecrop' and 'Legacy' respectively were resolved. Differential gene expression analyses were grouped into four cluster profiles based on changes in transcript abundance between harvest and 24 days post-harvest. A total of 290 unigenes were up-regulated in 'Legacy' only, 685 were up-regulated in 'Bluecrop', 252 were up-regulated in both cultivars and 948 were down-regulated in both cultivars between harvest and 24 days post-harvest. Unigenes showing significant differential expression between harvest and following post-harvest cold-storage were grouped into classes of biological processes including stress responses, cell wall metabolism, wax metabolism, calcium metabolism, cellular components, and biological processes. In total 21 differentially expressed unigenes with a putative role in regulating the response to post-harvest cold-storage in the two cultivars were identified from the de novo transcriptome assemblies performed. The results presented provide a stable foundation from which to perform further analyses with which to functionally validate the candidate genes identified, and to begin to understand the genetic mechanisms controlling changes in firmness in blueberry fruits post-harvest.


Assuntos
Mirtilos Azuis (Planta)/crescimento & desenvolvimento , Mirtilos Azuis (Planta)/genética , Sequenciamento de Nucleotídeos em Larga Escala , Transcriptoma/genética , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Anotação de Sequência Molecular , Análise de Componente Principal , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Tetraploidia
8.
Front Plant Sci ; 12: 692628, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234801

RESUMO

Genotyping by sequencing approaches have been widely applied in major crops and are now being used in horticultural crops like berries and fruit trees. As the original and largest producer of cultivated blueberry, the United States maintains the most diverse blueberry germplasm resources comprised of many species of different ploidy levels. We previously constructed an interspecific mapping population of diploid blueberry by crossing the parent F1#10 (Vaccinium darrowii Fla4B × diploid V. corymbosum W85-20) with the parent W85-23 (diploid V. corymbosum). Employing the Capture-Seq technology developed by RAPiD Genomics, with an emphasis on probes designed in predicted gene regions, 117 F1 progeny, the two parents, and two grandparents of this population were sequenced, yielding 131.7 Gbp clean sequenced reads. A total of 160,535 single nucleotide polymorphisms (SNPs), referenced to 4,522 blueberry genome sequence scaffolds, were identified and subjected to a parent-dependent sliding window approach to further genotype the population. Recombination breakpoints were determined and marker bins were deduced to construct a high density linkage map. Twelve blueberry linkage groups (LGs) consisting of 17,486 SNP markers were obtained, spanning a total genetic distance of 1,539.4 cM. Among 18 horticultural traits phenotyped in this population, quantitative trait loci (QTLs) that were significant over at least 2 years were identified for chilling requirement, cold hardiness, and fruit quality traits of color, scar size, and firmness. Interestingly, in 1 year, a QTL associated with timing of early bloom, full bloom, petal fall, and early green fruit was identified in the same region harboring the major QTL for chilling requirement. In summary, we report here the first high density bin map of a diploid blueberry mapping population and the identification of several horticulturally important QTLs.

9.
PLoS One ; 16(5): e0248089, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34019543

RESUMO

Extreme cold and frost cause significant stress to plants which can potentially be lethal. Low temperature freezing stress can cause significant and irreversible damage to plant cells and can induce physiological and metabolic changes that impact on growth and development. Low temperatures cause physiological responses including winter dormancy and autumn cold hardening in strawberry (Fragaria) species, and some diploid F. vesca accessions have been shown to have adapted to low-temperature stresses. To study the genetics of freezing tolerance, a F. vesca mapping population of 143 seedlings segregating for differential responses to freezing stress was raised. The progeny was mapped using 'Genotyping-by-Sequencing' and a linkage map of 2,918 markers at 851 loci was resolved. The mapping population was phenotyped for freezing tolerance response under controlled and replicated laboratory conditions and subsequent quantitative trait loci analysis using interval mapping revealed a single significant quantitative trait locus on Fvb2 in the physical interval 10.6 Mb and 15.73 Mb on the F. vesca v4.0 genome sequence. This physical interval contained 896 predicted genes, several of which had putative roles associated with tolerance to abiotic stresses including freezing. Differential expression analysis of the 896 QTL-associated gene predictions in the leaves and crowns from 'Alta' and 'NCGR1363' parental genotypes revealed genotype-specific changes in transcript accumulation in response to low temperature treatment as well as expression differences between genotypes prior to treatment for many of the genes. The putative roles, and significant interparental differential expression levels of several of the genes reported here identified them as good candidates for the control of the effects of freezing tolerance at the QTL identified in this investigation and the possible role of these candidate genes in response to freezing stress is discussed.


Assuntos
Resposta ao Choque Frio , Fragaria/genética , Locos de Características Quantitativas , Aclimatação , Congelamento , Proteínas de Plantas/genética
10.
Artigo em Inglês | MEDLINE | ID: mdl-32923882

RESUMO

PURPOSE: The microsatellite instability (MSI) or deficient mismatch repair (dMMR) phenotype is usually regarded as a single biologic entity, given the absence of comparative analyses regarding prognosis and response to chemotherapy between sporadic and familial dMMR cancers. PATIENTS AND METHODS: Patients with stage III colon cancers were randomly assigned to FOLFOX (leucovorin, fluorouracil, and oxaliplatin) with or without cetuximab in 2 large adjuvant phase III trials (N = 5,577). Among patients with MSI and KRAS exon 2 wild-type (WT) tumors, the prognostic and predictive impacts of sporadic versus familial dMMR cancers and BRAF V600E mutational status were determined. Multivariable Cox proportional hazards models were used to assess disease-free survival (DFS) by treatment arm, adjusting for age, sex, tumor grade, Eastern Cooperative Oncology Group performance status, pT/pN stage, and primary tumor location. RESULTS: Among patients with MSI status with complete data for dMMR mechanism analysis (n = 354), 255 (72%) had sporadic (BRAF mutation and/or MLH1 methylation) and 99 (28%) had familial tumors (BRAF WT and unmethylated MLH1 or loss of MSH2/MSH6/PMS2 protein expression). A large proportion of dMMR sporadic tumors were mutated for BRAF (n = 200). In patients treated with FOLFOX, DFS did not differ statistically by dMMR mechanism, whereas in patients treated with FOLFOX plus cetuximab, those with sporadic tumors had worse DFS than those with familial cancers (multivariable hazard ratio, 2.69; 95% CI, 1.02 to 7.08; P = .04). Considering the predictive utility, the interaction between treatment and dMMR mechanism was significant (P = .03). Furthermore, a nonsignificant trend toward a deleterious effect of adding cetuximab to FOLFOX was observed in patients with BRAF-mutant but not BRAF WT tumors. CONCLUSION: The addition of cetuximab to adjuvant FOLFOX was associated with shorter DFS in patients with sporadic dMMR colon cancer. Additional studies are needed to validate these results in metastatic disease.

11.
Hortic Res ; 7: 125, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821408

RESUMO

Strawberries are rich in polyphenols which impart health benefits when metabolized by the gut microbiome, including anti-inflammatory, neuroprotective, and antiproliferative effects. In addition, polyphenolic anthocyanins contribute to the attractive color of strawberry fruits. However, the genetic basis of polyphenol biosynthesis has not been extensively studied in strawberry. In this investigation, ripe fruits from three cultivated strawberry populations were characterized for polyphenol content using HPLC-DAD-MSn and genotyped using the iStraw35k array. GWAS and QTL analyses identified genetic loci controlling polyphenol biosynthesis. QTL were identified on four chromosomes for pelargonidin-3-O-malonylglucoside, pelargonidin-3-O-acetylglucoside, cinnamoyl glucose, and ellagic acid deoxyhexoside biosynthesis. Presence/absence of ellagic acid deoxyhexoside and pelargonidin-3-O-malonylglucoside was found to be under the control of major gene loci on LG1X2 and LG6b, respectively, on the F. × ananassa linkage maps. Interrogation of gene predictions in the F. vesca reference genome sequence identified a single candidate gene for ellagic acid deoxyhexoside biosynthesis, while seven malonyltransferase genes were identified as candidates for pelargonidin-3-O-malonylglucoside biosynthesis. Homologous malonyltransferase genes were identified in the F. × ananassa 'Camarosa' genome sequence but the candidate for ellagic acid deoxyhexoside biosynthesis was absent from the 'Camarosa' sequence. This study demonstrated that polyphenol biosynthesis in strawberry is, in some cases, under simple genetic control, supporting previous observations of the presence or absence of these compounds in strawberry fruits. It has also shed light on the mechanisms controlling polyphenol biosynthesis and enhanced the knowledge of these biosynthesis pathways in strawberry. The above findings will facilitate breeding for strawberries enriched in compounds with beneficial health effects.

12.
Contemp Clin Trials Commun ; 17: 100492, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31872158

RESUMO

PURPOSE: Missing data commonly occur in cancer clinical trials (CCT) and may hinder the search for alternative trial endpoints. We consider reasons for missing tumor measurement (TM) data in CCT and how missing TM data are typically handled. We explore the potential impact of missing TM data on predictive ability of a set of TM-based endpoints. METHODS: Literature review identifies reasons for and approaches to handling missing TM data. Data from 3 actual clinical trials were used for illustration. A sensitivity analysis of the potential impact of missing TM data was performed by comparing overall survival (OS) predictive ability of alternative endpoints using observed and imputed data. RESULTS: Reasons for missing TM data in CCT are presented, based on the literature review and the three trials. Although missing TM data impacted individual objective status (e.g. 12-week status changed for 53% of patients in one imputation set), it surprisingly only minimally impacted endpoint predictive ability (e.g. median c-indices of 500 imputed datasets ranged from 0.566 to 0.570 for N9741, 0.592-0.616 for N9841, and 0.542-0.624 for N0026). CONCLUSION: By understanding the reasons for missingness, we can better anticipate them and minimize their occurrence. Our preliminary analysis suggests missing TM data may not impact endpoint predictive ability, but could impact objective response status classification; however these findings require further validation. With response status accepted as an important phase II endpoint in the development of new cancer therapies (including immunotherapy), we urge that in CCT complete TM data collection and adherence to protocol-defined disease evaluation as closely as possible be a priority.

13.
PLoS One ; 14(9): e0222829, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31536602

RESUMO

Strawberry powdery mildew (Podosphaera aphanis Wallr.) is a pathogen which infects the leaves, fruit, stolon and flowers of the cultivated strawberry (Fragaria ×ananassa), causing major yield losses, primarily through unmarketable fruit. The primary commercial control of the disease is the application of fungicidal sprays. However, as the use of key active ingredients of commercial fungicides is becoming increasingly restricted, interest in developing novel strawberry cultivars exhibiting resistance to the pathogen is growing rapidly. In this study, a mapping population derived from a cross between two commercial strawberry cultivars ('Sonata' and 'Babette') was genotyped with single nucleotide polymorphism (SNP) markers from the Axiom iStraw90k genotyping array and phenotyped for powdery mildew susceptibility in both glasshouse and field environments. Three distinct, significant QTLs for powdery mildew resistance were identified across the two experiments. Through comparison with previous studies and scrutiny of the F. vesca genome sequence, candidate genes underlying the genetic control of this trait were identified.


Assuntos
Fragaria/genética , Frutas/genética , Genes de Plantas/genética , Doenças das Plantas/genética , Locos de Características Quantitativas/genética , Ascomicetos/fisiologia , Mapeamento Cromossômico , Cruzamentos Genéticos , Resistência à Doença/genética , Fragaria/classificação , Fragaria/microbiologia , Frutas/microbiologia , Genoma de Planta/genética , Genótipo , Interações Hospedeiro-Patógeno , Fenótipo , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Especificidade da Espécie
14.
Front Plant Sci ; 10: 924, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379904

RESUMO

Verticillium dahliae is a highly detrimental pathogen of soil cultivated strawberry (Fragaria x ananassa). Breeding of Verticillium wilt resistance into commercially viable strawberry cultivars can help mitigate the impact of the disease. In this study we describe novel sources of resistance identified in multiple strawberry populations, creating a wealth of data for breeders to exploit. Pathogen-informed experiments have allowed the differentiation of subclade-specific resistance responses, through studying V. dahliae subclade II-1 specific resistance in the cultivar "Redgauntlet" and subclade II-2 specific resistance in "Fenella" and "Chandler." A large-scale low-cost phenotyping platform was developed utilizing automated unmanned vehicles and near infrared imaging cameras to assess field-based disease trials. The images were used to calculate disease susceptibility for infected plants through the normalized difference vegetation index score. The automated disease scores showed a strong correlation with the manual scores. A co-dominant resistant QTL; FaRVd3D, present in both "Redgauntlet" and "Hapil" cultivars exhibited a major effect of 18.3% when the two resistance alleles were combined. Another allele, FaRVd5D, identified in the "Emily" cultivar was associated with an increase in Verticillium wilt susceptibility of 17.2%, though whether this allele truly represents a susceptibility factor requires further research, due to the nature of the F1 mapping population. Markers identified in populations were validated across a set of 92 accessions to determine whether they remained closely linked to resistance genes in the wider germplasm. The resistant markers FaRVd2B from "Redgauntlet" and FaRVd6D from "Chandler" were associated with resistance across the wider germplasm. Furthermore, comparison of imaging versus manual phenotyping revealed the automated platform could identify three out of four disease resistance markers. As such, this automated wilt disease phenotyping platform is considered to be a good, time saving, substitute for manual assessment.

15.
Ann Surg ; 269(4): 589-595, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30080730

RESUMO

OBJECTIVE: To determine the disease-free survival (DFS) and recurrence after the treatment of patients with rectal cancer with open (OPEN) or laparoscopic (LAP) resection. BACKGROUND: This randomized clinical trial (ACOSOG [Alliance] Z6051), performed between 2008 and 2013, compared LAP and OPEN resection of stage II/III rectal cancer, within 12 cm of the anal verge (T1-3, N0-2, M0) in patients who received neoadjuvant chemoradiotherapy. The rectum and mesorectum were resected using open instruments for rectal dissection (included hybrid hand-assisted laparoscopic) or with laparoscopic instruments under pneumoperitoneum. The 2-year DFS and recurrence were secondary endpoints of Z6051. METHODS: The DFS and recurrence were not powered, and are being assessed for superiority. Recurrence was determined at 3, 6, 9, 12, and every 6 months thereafter, using carcinoembryonic antigen, physical examination, computed tomography, and colonoscopy. In all, 486 patients were randomized to LAP (243) or OPEN (243), with 462 eligible for analysis (LAP = 240 and OPEN = 222). Median follow-up is 47.9 months. RESULTS: The 2-year DFS was LAP 79.5% (95% confidence interval [CI] 74.4-84.9) and OPEN 83.2% (95% CI 78.3-88.3). Local and regional recurrence was 4.6% LAP and 4.5% OPEN. Distant recurrence was 14.6% LAP and 16.7% OPEN.Disease-free survival was impacted by unsuccessful resection (hazard ratio [HR] 1.87, 95% CI 1.21-2.91): composite of incomplete specimen (HR 1.65, 95% CI 0.85-3.18); positive circumferential resection margins (HR 2.31, 95% CI 1.40-3.79); positive distal margin (HR 2.53, 95% CI 1.30-3.77). CONCLUSION: Laparoscopic assisted resection of rectal cancer was not found to be significantly different to OPEN resection of rectal cancer based on the outcomes of DFS and recurrence.


Assuntos
Laparoscopia , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Retais/epidemiologia , Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Intervalo Livre de Doença , Seguimentos , Humanos , Estadiamento de Neoplasias , Neoplasias Retais/patologia
16.
J Biopharm Stat ; 29(2): 271-286, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30403559

RESUMO

Phase I designs traditionally use the dose-limiting toxicity (DLT), a binary endpoint from the first treatment cycle, to identify the maximum-tolerated dose (MTD) assuming a monotonically increasing relationship between dose and efficacy. In this article, we establish a general framework for a multi-stage adaptive design where we jointly model a continuous efficacy outcome and continuous/quasi-continuous toxicity endpoints from multiple treatment cycles. The normalized Total Toxicity Profile (nTTP) is used as an illustration for quasi-continuous toxicity endpoints, and we replace DLT with nTTP to take into account multiple grades and types of toxicities. In addition, the proposed design accommodates non-monotone dose-efficacy relationships, and longitudinal toxicity data in effort to capture the adverse events from multiple cycles. Stage 1 of our design uses toxicity data to perform dose-escalation and identify a set of initially allowable (safe) doses; stage 2 of our design incorporates an efficacy outcome to update the set of allowable doses for each new cohort and randomizes the new cohort of patients to the allowable doses with emphasis towards those with higher predicted efficacy. Stage 3 uses all data from all treated patients at the end of the trial to make final recommendations. Simulations showed that the design had a high probability of making the correct dose selection and good overdose control across various dose-efficacy and dose-toxicity scenarios. In addition, the proposed design allows for early termination when all doses are too toxic. To our best knowledge, the proposed dual-endpoint dose-finding design is the first such study to incorporate multiple cycles of toxicities and a continuous efficacy outcome.


Assuntos
Antineoplásicos/administração & dosagem , Ensaios Clínicos Fase I como Assunto/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Modelos Estatísticos , Projetos de Pesquisa/estatística & dados numéricos , Resultado do Tratamento , Algoritmos , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Teorema de Bayes , Ensaios Clínicos Fase I como Assunto/estatística & dados numéricos , Simulação por Computador , Relação Dose-Resposta a Droga , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Humanos , Estudos Longitudinais , Dose Máxima Tolerável
17.
Eur J Cancer ; 103: 205-213, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30268921

RESUMO

PURPOSE: Patients with left-sided colon tumours have better survival and respond differently to biologics compared with patients with right-sided tumours. Left-sided colon tumours and rectal cancers are often grouped together. Herein, we examined the clinicopathological differences and outcomes between left-sided colon and rectal cancers. PATIENTS AND METHODS: Data from 2879 metastatic colorectal cancer patients enrolled on six first-line clinical trials during 2004-2010 were pooled. Patients were included if the primary tumour origin was clearly defined. Progression-free survival (PFS) and overall survival (OS) were compared in the two groups after adjusting for patient and tumour characteristics, metastatic sites and the first-line regimen. RESULTS: In total, 1374 patients with metastatic left-sided colon cancer and 1505 patients with metastatic rectal cancers were evaluated. Left-sided colon cancer patients were more likely to be female (40.1% versus 32.6%; P < 0.0001) and older (31.0% ≥ 70 years versus 25.8%; P = 0.0033) compared with rectal cancers patients. Patients with left-sided colon cancer had higher rates of liver metastases (80.9% versus 72.3%, P < 0.0001) but lower rates of lung metastases (34.2% versus 53.8%, P < 0.0001). KRAS mutations were slightly less frequent among left-sided tumours (34.8% versus 40.5%; P = 0.0103). Patients with left-sided tumours had approximately similar PFS (median 7.4 versus 6.9 months; hazard ratio [HR] 0.92, 95% confidence interval [CI] 0.87-1.03; P = 0.1998) and OS (median 17.4 versus 16.6 months; HR 0.99, 95% CI 0.91-1.07; P = 0.7597) compared with rectal cancer patients. CONCLUSION: The site of tumour origin within the left side was not prognostic of outcomes. Moreover, neither bevacizumab nor cetuximab impacted, differently, the findings of the comparisons in outcomes between patients with left-sided colon tumours or rectal cancers.


Assuntos
Neoplasias do Colo/terapia , Neoplasias Retais/terapia , Neoplasias do Colo/patologia , Feminino , Pool Gênico , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Retais/patologia
18.
Theor Appl Genet ; 131(9): 1995-2007, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29971472

RESUMO

Key Message Powdery mildew resistance in two strawberry mapping populations is controlled by both stable and transient novel QTL of moderate effect. Some low transferability of QTL across wider germplasm was observed. The obligate biotrophic fungus Podosphaera aphanis is the causative agent of powdery mildew on cultivated strawberry (Fragaria × ananassa). Genotypes from two bi-parental mapping populations 'Emily' × 'Fenella' and 'Redgauntlet' × 'Hapil' were phenotyped for powdery mildew disease severity in a series of field trials. Here, we report multiple QTL associated with resistance to powdery mildew, identified in ten phenotyping events conducted across different years and locations. Six QTL show a level of stable resistance across multiple phenotyping events; however, many other QTL were represented in a single phenotyping event and therefore must be considered transient. Subsequent screening of identified QTL across a validation set determined whether identified QTL remained closely linked to the associated resistance gene in the wider germplasm. Furthermore, a preliminary association analysis identified a novel conserved locus for further investigation. Our data suggest that resistance is highly complex and that multiple, primarily additive, sources of quantitative resistance to powdery mildew exist across strawberry germplasm. Utilisation of the reported markers in marker-assisted breeding or genomic selection would lead to improved powdery mildew-resistant strawberry cultivars, particularly where the studied parents, progeny and close pedigree material are included in breeding germplasm.


Assuntos
Resistência à Doença/genética , Fragaria/genética , Doenças das Plantas/genética , Locos de Características Quantitativas , Ascomicetos , Mapeamento Cromossômico , Fragaria/microbiologia , Ligação Genética , Genótipo , Fenótipo , Melhoramento Vegetal , Doenças das Plantas/microbiologia
19.
Eur J Cancer ; 96: 115-124, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29729562

RESUMO

BACKGROUND: Patient characteristics and stratification factors are important factors influencing trial outcomes. Uniform reporting on these parameters would facilitate cross-study comparisons and extrapolation of trial results to clinical practice. In 2007, standardisation on patient characteristics reporting and stratification in metastatic colorectal cancer (mCRC) trials was proposed. We investigated the reporting of prognostic factors and implementation of this proposal in mCRC trials published from 2005 to 2016. METHODS: We searched PubMed and Embase (January 2005 - June 2016) for first-line phase 3 mCRC trials. Patient characteristics reporting and use of stratification factors were extracted and analysed for adherence to the proposal from 2007. RESULTS: Sixty-seven trials (35,315 patients) were identified, reporting 48 different patient characteristics (median: 9 [range: 5-18] per study). Age, gender, performance status (PS), primary tumour site and adjuvant chemotherapy were frequently reported (87%-100%), in contrast to laboratory values, such as alkaline phosphatase, lactate dehydrogenase and white blood cell count (10%-25%). We identified 29 different stratification factors (median: 3 [range: 1-9] per study). The most common strata were PS and treatment centre (>60%). A median of 8/12 (range: 4-11) of the proposed parameters was reported. Although the percentage of studies reporting each factor slightly increased over time, there was no significant correlation between publication year and adherence to the proposal from 2007. CONCLUSIONS: We observed persistent heterogeneity in the reporting of patient characteristics and use of stratification factors in first-line mCRC trials. The proposal from 2007 has not led to increased uniformity of patient characteristics reporting and use of stratification over time. There is an urgent need to address this issue to improve the interpretation of trial results.


Assuntos
Ensaios Clínicos Fase III como Assunto/normas , Neoplasias Colorretais/terapia , Seleção de Pacientes , Projetos de Pesquisa/normas , Tomada de Decisão Clínica , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Metástase Neoplásica , Fatores de Risco , Resultado do Tratamento
20.
Gigascience ; 7(4): 1-14, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29659812

RESUMO

Background: The genus Potentilla is closely related to that of Fragaria, the economically important strawberry genus. Potentilla micrantha is a species that does not develop berries but shares numerous morphological and ecological characteristics with Fragaria vesca. These similarities make P. micrantha an attractive choice for comparative genomics studies with F. vesca. Findings: In this study, the P. micrantha genome was sequenced and annotated, and RNA-Seq data from the different developmental stages of flowering and fruiting were used to develop a set of gene predictions. A 327 Mbp sequence and annotation of the genome of P. micrantha, spanning 2674 sequence contigs, with an N50 size of 335,712, estimated to cover 80% of the total genome size of the species was developed. The genus Potentilla has a characteristically larger genome size than Fragaria, but the recovered sequence scaffolds were remarkably collinear at the micro-syntenic level with the genome of F. vesca, its closest sequenced relative. A total of 33,602 genes were predicted, and 95.1% of bench-marking universal single-copy orthologous genes were complete within the presented sequence. Thus, we argue that the majority of the gene-rich regions of the genome have been sequenced. Conclusions: Comparisons of RNA-Seq data from the stages of floral and fruit development revealed genes differentially expressed between P. micrantha and F. vesca.The data presented are a valuable resource for future studies of berry development in Fragaria and the Rosaceae and they also shed light on the evolution of genome size and organization in this family.


Assuntos
Flores/genética , Fragaria/genética , Frutas/genética , Genoma de Planta , Potentilla/genética , Flores/crescimento & desenvolvimento , Fragaria/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Filogenia , Potentilla/crescimento & desenvolvimento , Análise de Sequência de RNA , Transcriptoma , Sequenciamento Completo do Genoma
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