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1.
Proc Natl Acad Sci U S A ; 121(16): e2309621121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38588415

RESUMO

Chromosomal instability (CIN) is the persistent reshuffling of cancer karyotypes via chromosome mis-segregation during cell division. In cancer, CIN exists at varying levels that have differential effects on tumor progression. However, mis-segregation rates remain challenging to assess in human cancer despite an array of available measures. We evaluated measures of CIN by comparing quantitative methods using specific, inducible phenotypic CIN models of chromosome bridges, pseudobipolar spindles, multipolar spindles, and polar chromosomes. For each, we measured CIN fixed and timelapse fluorescence microscopy, chromosome spreads, six-centromere FISH, bulk transcriptomics, and single-cell DNA sequencing (scDNAseq). As expected, microscopy of tumor cells in live and fixed samples significantly correlated (R = 0.72; P < 0.001) and sensitively detect CIN. Cytogenetics approaches include chromosome spreads and 6-centromere FISH, which also significantly correlate (R = 0.76; P < 0.001) but had limited sensitivity for lower rates of CIN. Bulk genomic DNA signatures and bulk transcriptomic scores, CIN70 and HET70, did not detect CIN. By contrast, scDNAseq detects CIN with high sensitivity, and significantly correlates with imaging methods (R = 0.82; P < 0.001). In summary, single-cell methods such as imaging, cytogenetics, and scDNAseq can measure CIN, with the latter being the most comprehensive method accessible to clinical samples. To facilitate the comparison of CIN rates between phenotypes and methods, we propose a standardized unit of CIN: Mis-segregations per Diploid Division. This systematic analysis of common CIN measures highlights the superiority of single-cell methods and provides guidance for measuring CIN in the clinical setting.


Assuntos
Instabilidade Cromossômica , Neoplasias , Humanos , Linhagem Celular Tumoral , Instabilidade Cromossômica/genética , Centrômero , Cariotipagem , Perfilação da Expressão Gênica , Segregação de Cromossomos , Aneuploidia
2.
PLoS Biol ; 21(10): e3002339, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37883329

RESUMO

Microtubule-targeted agents are commonly used for cancer treatment, though many patients do not benefit. Microtubule-targeted drugs were assumed to elicit anticancer activity via mitotic arrest because they cause cell death following mitotic arrest in cell culture. However, we recently demonstrated that intratumoral paclitaxel concentrations are insufficient to induce mitotic arrest and rather induce chromosomal instability (CIN) via multipolar mitotic spindles. Here, we show in metastatic breast cancer and relevant human cellular models that this mechanism is conserved among clinically useful microtubule poisons. While multipolar divisions typically produce inviable progeny, multipolar spindles can be focused into near-normal bipolar spindles at any stage of mitosis. Using a novel method to quantify the rate of CIN, we demonstrate that cell death positively correlates with net loss of DNA. Spindle focusing decreases CIN and causes resistance to diverse microtubule poisons, which can be counteracted by addition of a drug that increases CIN without affecting spindle polarity. These results demonstrate conserved mechanisms of action and resistance for diverse microtubule-targeted agents. Trial registration: clinicaltrials.gov, NCT03393741.


Assuntos
Antineoplásicos , Venenos , Humanos , Microtúbulos/metabolismo , Fuso Acromático , Mitose , Cinetocoros , Antineoplásicos/farmacologia , Venenos/metabolismo
3.
Chromosome Res ; 32(1): 2, 2024 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-38367036

RESUMO

Quantitative measures of CIN are crucial to our understanding of its role in cancer. Technological advances have changed the way CIN is quantified, offering increased accuracy and insight. Here, we review measures of CIN through its rise as a field, discuss considerations for its measurement, and look forward to future quantification of CIN.


Assuntos
Aneuploidia , Neoplasias , Humanos , Instabilidade Cromossômica , Neoplasias/genética
4.
Ann Surg Oncol ; 31(1): 488-498, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37782415

RESUMO

BACKGROUND: While lower socioeconomic status has been shown to correlate with worse outcomes in cancer care, data correlating neighborhood-level metrics with outcomes are scarce. We aim to explore the association between neighborhood disadvantage and both short- and long-term postoperative outcomes in patients undergoing pancreatectomy for pancreatic ductal adenocarcinoma (PDAC). PATIENTS AND METHODS: We retrospectively analyzed 243 patients who underwent resection for PDAC at a single institution between 1 January 2010 and 15 September 2021. To measure neighborhood disadvantage, the cohort was divided into tertiles by Area Deprivation Index (ADI). Short-term outcomes of interest were minor complications, major complications, unplanned readmission within 30 days, prolonged hospitalization, and delayed gastric emptying (DGE). The long-term outcome of interest was overall survival. Logistic regression was used to test short-term outcomes; Cox proportional hazards models and Kaplan-Meier method were used for long-term outcomes. RESULTS: The median ADI of the cohort was 49 (IQR 32-64.5). On adjusted analysis, the high-ADI group demonstrated greater odds of suffering a major complication (odds ratio [OR], 2.78; 95% confidence interval [CI], 1.26-6.40; p = 0.01) and of an unplanned readmission (OR, 3.09; 95% CI, 1.16-9.28; p = 0.03) compared with the low-ADI group. There were no significant differences between groups in the odds of minor complications, prolonged hospitalization, or DGE (all p > 0.05). High ADI did not confer an increased hazard of death (p = 0.63). CONCLUSIONS: We found that worse neighborhood disadvantage is associated with a higher risk of major complication and unplanned readmission after pancreatectomy for PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Pancreatectomia/efeitos adversos , Pancreatectomia/métodos , Estudos Retrospectivos , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Características da Vizinhança
5.
N Engl J Med ; 383(9): 825-835, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32846061

RESUMO

BACKGROUND: RET mutations occur in 70% of medullary thyroid cancers, and RET fusions occur rarely in other thyroid cancers. In patients with RET-altered thyroid cancers, the efficacy and safety of selective RET inhibition are unknown. METHODS: We enrolled patients with RET-mutant medullary thyroid cancer with or without previous vandetanib or cabozantinib treatment, as well as those with previously treated RET fusion-positive thyroid cancer, in a phase 1-2 trial of selpercatinib. The primary end point was an objective response (a complete or partial response), as determined by an independent review committee. Secondary end points included the duration of response, progression-free survival, and safety. RESULTS: In the first 55 consecutively enrolled patients with RET-mutant medullary thyroid cancer who had previously received vandetanib, cabozantinib, or both, the percentage who had a response was 69% (95% confidence interval [CI], 55 to 81), and 1-year progression-free survival was 82% (95% CI, 69 to 90). In 88 patients with RET-mutant medullary thyroid cancer who had not previously received vandetanib or cabozantinib, the percentage who had a response was 73% (95% CI, 62 to 82), and 1-year progression-free survival was 92% (95% CI, 82 to 97). In 19 patients with previously treated RET fusion-positive thyroid cancer, the percentage who had a response was 79% (95% CI, 54 to 94), and 1-year progression-free survival was 64% (95% CI, 37 to 82). The most common adverse events of grade 3 or higher were hypertension (in 21% of the patients), increased alanine aminotransferase level (in 11%), increased aspartate aminotransferase level (in 9%), hyponatremia (in 8%), and diarrhea (in 6%). Of all 531 patients treated, 12 (2%) discontinued selpercatinib owing to drug-related adverse events. CONCLUSIONS: In this phase 1-2 trial, selpercatinib showed durable efficacy with mainly low-grade toxic effects in patients with medullary thyroid cancer with and without previous vandetanib or cabozantinib treatment. (Funded by Loxo Oncology and others; LIBRETTO-001 ClinicalTrials.gov number, NCT03157128.).


Assuntos
Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas c-ret/antagonistas & inibidores , Pirazóis/administração & dosagem , Piridinas/administração & dosagem , Neoplasias da Glândula Tireoide/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipertensão/induzido quimicamente , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mutação , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Proto-Oncogênicas c-ret/análise , Proteínas Proto-Oncogênicas c-ret/genética , Pirazóis/efeitos adversos , Piridinas/efeitos adversos , Transaminases/sangue , Resultado do Tratamento , Adulto Jovem
6.
J Surg Oncol ; 128(2): 280-288, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37073788

RESUMO

BACKGROUND: Outcomes for pancreatic adenocarcinoma (PDAC) remain difficult to prognosticate. Multiple models attempt to predict survival following the resection of PDAC, but their utility in the neoadjuvant population is unknown. We aimed to assess their accuracy among patients that received neoadjuvant chemotherapy (NAC). METHODS: We performed a multi-institutional retrospective analysis of patients who received NAC and underwent resection of PDAC. Two prognostic systems were evaluated: the Memorial Sloan Kettering Cancer Center Pancreatic Adenocarcinoma Nomogram (MSKCCPAN) and the American Joint Committee on Cancer (AJCC) staging system. Discrimination between predicted and actual disease-specific survival was assessed using the Uno C-statistic and Kaplan-Meier method. Calibration of the MSKCCPAN was assessed using the Brier score. RESULTS: A total of 448 patients were included. There were 232 (51.8%) females, and the mean age was 64.1 years (±9.5). Most had AJCC Stage I or II disease (77.7%). For the MSKCCPAN, the Uno C-statistic at 12-, 24-, and 36-month time points was 0.62, 0.63, and 0.62, respectively. The AJCC system demonstrated similarly mediocre discrimination. The Brier score for the MSKCCPAN was 0.15 at 12 months, 0.26 at 24 months, and 0.30 at 36 months, demonstrating modest calibration. CONCLUSIONS: Current survival prediction models and staging systems for patients with PDAC undergoing resection after NAC have limited accuracy.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adenocarcinoma/cirurgia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/cirurgia , Terapia Neoadjuvante , Estadiamento de Neoplasias , Nomogramas , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/cirurgia , Prognóstico , Estudos Retrospectivos , Neoplasias Pancreáticas
7.
J Oncol Pharm Pract ; 29(5): 1094-1102, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35369813

RESUMO

PURPOSE: Molecular tumor boards provide precision treatment recommendations based on cancer genomic profile. However, practical barriers limit their benefits. We studied the clinical utility of the precision medicine molecular tumor board (PMMTB) and described challenges with PMMTB implementation. METHODS: An observational cohort study included patients reviewed by the PMMTB between September 2015 to December 2017. Patients who had consented to the registry study were included. The primary endpoint of this study was time on treatment (ToT) ratio. Clinical utility was established if the primary endpoint had least 15% of patients achieving a ToT ratio of ≥1.3. RESULTS: Overall, 278 patients were presented to the PMMTB and 113 cases were included in the final analysis. The PMMTB identified at least one nonstandard of care (SOC) clinically actionable mutation for 69.0% (78/113) of cases. In patients who received non-SOC treatment, 43.8% (7/16) achieved a ToT ratio of 1.3 or more (p < 0.001). Fifty-nine patients did not receive non-SOC recommendations. Reasons for not pursuing treatment included 35.6% having response to current treatment, 20.3% died prior to starting or considering PMMTB recommendations, 13.6% pursued other treatment options based on clinician discretion, another 10.2% pursued other treatment options because clinical trials recommended were not geographically accessible, 8.5% had rapid decline of performance status, 6.8% lacked of financial support for treatment, and 5.1% were excluded from clinical trials due to abnormal laboratory values. CONCLUSION: The regional PMMTB non-SOC recommendations benefitted a majority of patients and additional processes were implemented to assist with non-SOC treatment accessibility.


Assuntos
Neoplasias , Medicina de Precisão , Humanos , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Mutação , Terapia de Alvo Molecular
8.
Breast Cancer Res Treat ; 191(2): 277-289, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34787761

RESUMO

PURPOSE: Conventional chemotherapies are a mainstay for metastatic breast cancers, though durable response is rare. Immunotherapies promise long-term responses thorough immune activation but have been underwhelming in breast cancer relative to other cancer types. Here, we review the mechanisms of existing strategies including chemotherapies and how they may cause breast cancers to become immunogenic to identify potential biomarkers for combinations of conventional and immunotherapies. CONCLUSION: Mechanistic considerations should inform biomarker development and patient selection for therapeutic combinations of drugs to combine with immune-checkpoint inhibitors.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Imunidade , Imunoterapia
9.
Breast Cancer Res Treat ; 196(3): 549-563, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36198984

RESUMO

PURPOSE: Although metastatic breast cancer (MBC) is treatable, it is not curable and most patients remain on treatment indefinitely. While oncologists commonly prescribe the recommended starting dose (RSD) from the FDA-approved label, patient tolerance may differ from that seen in clinical trials. We report on a survey of medical oncologists' perspectives about treatment-related toxicity and willingness to discuss flexible dosing with patients. METHODS: We disseminated a confidential survey via social media/email in Spring 2021. Eligible respondents needed to be US-based medical oncologists with experience treating patients with MBC. RESULTS: Of 131 responses, 119 were eligible. Physicians estimated that 47% of their patients reported distressing treatment-related side effects; of these, 15% visited the Emergency Room/hospital and 37% missed treatment. 74% (n = 87) of doctors reported improvement of patient symptoms after dose reduction. 87% (n = 104) indicated that they had ever, if appropriate, initiated treatment at lower doses. Most (85%, n = 101) respondents did not believe that the RSD is always more effective than a lower dose and 97% (n = 115) were willing to discuss individualized dosing with patients. CONCLUSION: Treatment-related side effects are prevalent among patients with MBC, resulting in missed treatments and acute care visits. To help patients tolerate treatment, oncologists may decrease initial and/or subsequent doses. The majority of oncologists reject the premise that a higher dose is always superior and are willing to discuss individualized dosing with patients. Given potential improvements regarding quality of life and clinical care, dose modifications should be part of routine shared decision-making between patients and oncologists.


Assuntos
Neoplasias da Mama , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Oncologistas , Humanos , Feminino , Neoplasias da Mama/patologia , Qualidade de Vida , Inquéritos e Questionários , Assistência Centrada no Paciente
10.
BMC Bioinformatics ; 22(1): 83, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33622236

RESUMO

BACKGROUND: Single-cell RNA-seq (scRNA-seq) enables the profiling of genome-wide gene expression at the single-cell level and in so doing facilitates insight into and information about cellular heterogeneity within a tissue. This is especially important in cancer, where tumor and tumor microenvironment heterogeneity directly impact development, maintenance, and progression of disease. While publicly available scRNA-seq cancer data sets offer unprecedented opportunity to better understand the mechanisms underlying tumor progression, metastasis, drug resistance, and immune evasion, much of the available information has been underutilized, in part, due to the lack of tools available for aggregating and analysing these data. RESULTS: We present CHARacterizing Tumor Subpopulations (CHARTS), a web application for exploring publicly available scRNA-seq cancer data sets in the NCBI's Gene Expression Omnibus. More specifically, CHARTS enables the exploration of individual gene expression, cell type, malignancy-status, differentially expressed genes, and gene set enrichment results in subpopulations of cells across tumors and data sets. Along with the web application, we also make available the backend computational pipeline that was used to produce the analyses that are available for exploration in the web application. CONCLUSION: CHARTS is an easy to use, comprehensive platform for exploring single-cell subpopulations within tumors across the ever-growing collection of public scRNA-seq cancer data sets. CHARTS is freely available at charts.morgridge.org.


Assuntos
Neoplasias , Análise de Sequência de RNA , Análise de Célula Única , Perfilação da Expressão Gênica , Humanos , Neoplasias/genética , RNA-Seq , Software , Microambiente Tumoral
11.
BMC Cancer ; 21(1): 186, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33622270

RESUMO

BACKGROUND: Targeting Protein for Xenopus Kinesin Like Protein 2 (TPX2) is a microtubule associated protein that functions in mitotic spindle assembly. TPX2 also localizes to the nucleus where it functions in DNA damage repair during S-phase. We and others have previously shown that TPX2 RNA levels are strongly associated with chromosomal instability (CIN) in breast and other cancers, and TPX2 RNA levels have been demonstrated to correlate with aggressive behavior and poor clinical outcome across a range of solid malignancies, including breast cancer. METHODS: We perform TPX2 IHC on a cohort of 253 primary breast cancers and adopt a clinically amenable scoring system to separate tumors into low, intermediate, or high TPX2 expression. We then correlate TPX2 expression against diverse pathologic parameters and important measures of clinical outcome, including disease-specific and overall survival. We link TPX2 expression to TP53 mutation and evaluate whether TPX2 is an independent predictor of chromosomal instability (CIN). RESULTS: We find that TPX2 nuclear expression strongly correlates with high grade morphology, elevated clinical stage, negative ER and PR status, and both disease-specific and overall survival. We also show that increased TPX2 nuclear expression correlates with elevated ploidy, supernumerary centrosomes, and TP53 mutation. TPX2 nuclear expression correlates with CIN via univariate analyses but is not independently predictive when compared to ploidy, Ki67, TP53 mutational status, centrosome number, and patient age. CONCLUSIONS: Our findings demonstrate a strong correlation between TPX2 nuclear expression and aggressive tumor behavior, and show that TPX2 overexpression frequently occurs in the setting of TP53 mutation and elevated ploidy. However, TPX2 expression is not an independent predictor of CIN where it fails to outperform existing clinical and pathologic metrics.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ciclo Celular/fisiologia , Núcleo Celular/química , Instabilidade Cromossômica , Proteínas Associadas aos Microtúbulos/fisiologia , Mutação , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Proteínas de Ciclo Celular/análise , Proteínas de Ciclo Celular/genética , Proliferação de Células , Estudos de Coortes , Feminino , Humanos , Proteínas Associadas aos Microtúbulos/análise , Proteínas Associadas aos Microtúbulos/genética , Pessoa de Meia-Idade , RNA Mensageiro/análise
12.
EMBO Rep ; 20(10): e48711, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31468671

RESUMO

During mitosis, sister chromatids attach to microtubules which generate ~ 700 pN pulling force focused on the centromere. We report that chromatin-localized signals generated by Polo-like kinase 1 (Plk1) maintain the integrity of the kinetochore and centromere against this force. Without sufficient Plk1 activity, chromosomes become misaligned after normal condensation and congression. These chromosomes are silent to the mitotic checkpoint, and many lag and mis-segregate in anaphase. Their centromeres and kinetochores lack CENP-A, CENP-C, CENP-T, Hec1, Nuf2, and Knl1; however, CENP-B is retained. CENP-A loss occurs coincident with secondary misalignment and anaphase onset. This disruption occurs asymmetrically prior to anaphase and requires tension generated by microtubules. Mechanistically, centromeres highly recruit PICH DNA helicase and PICH depletion restores kinetochore disruption in pre-anaphase cells. Furthermore, anaphase defects are significantly reduced by tethering Plk1 to chromatin, including H2B, and INCENP, but not to CENP-A. Taken as a whole, this demonstrates that Plk1 signals are crucial for stabilizing centromeric architecture against tension.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Cinetocoros/metabolismo , Microtúbulos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fenômenos Biomecânicos , Linhagem Celular , Proteína Centromérica A/metabolismo , Cromossomos Humanos/metabolismo , Fragmentação do DNA , DNA Helicases/metabolismo , Humanos , Modelos Biológicos , Quinase 1 Polo-Like
13.
Genes Chromosomes Cancer ; 59(11): 627-638, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32557940

RESUMO

Chromosome instability (CIN) generates genetic and karyotypic diversity that is common in hematological malignancies. Low to moderate levels of CIN are well tolerated and can promote cancer proliferation. However, high levels of CIN are lethal. Thus, CIN may serve both as a prognostic factor to predict clinical outcome and as a predictive biomarker. A retrospective study was performed to evaluate CIN in acute myeloid leukemia (AML). Chromosome mis-segregation frequency was correlated with clinical outcome in bone marrow core biopsy specimens from 17 AML cases. Additionally, we induced chromosome segregation errors in AML cell lines with AZ3146, an inhibitor of the Mps1 mitotic checkpoint kinase, to quantify the phenotypic effects of high CIN. We observed a broad distribution of chromosome mis-segregation frequency in AML bone marrow core specimens. High CIN correlated with complex karyotype in AML, as expected, although there was no clear survival effect. In addition to CIN, experimentally inducing chromosome segregation errors by Mps1 inhibition in AML cell lines causes DNA damage, micronuclei formation, and upregulation of interferon stimulated genes. High levels of CIN appear to be immunostimulatory, suggesting an opportunity to combine mitotic checkpoint inhibitors with immunotherapy in treatment of AML.


Assuntos
Instabilidade Cromossômica , Interferons/genética , Leucemia Mieloide Aguda/genética , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Segregação de Cromossomos , Dano ao DNA , Humanos , Interferons/metabolismo , Cariótipo , Leucemia Mieloide Aguda/patologia , Mutagênicos/toxicidade , Inibidores de Proteínas Quinases/toxicidade , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Regulação para Cima
14.
J Biol Chem ; 294(16): 6531-6549, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30804208

RESUMO

The centrosome, consisting of two centrioles surrounded by a dense network of proteins, is the microtubule-organizing center of animal cells. Polo-like kinase 4 (PLK4) is a Ser/Thr protein kinase and the master regulator of centriole duplication, but it may play additional roles in centrosome function. To identify additional proteins regulated by PLK4, we generated an RPE-1 human cell line with a genetically engineered "analog-sensitive" PLK4AS, which genetically encodes chemical sensitivity to competitive inhibition via a bulky ATP analog. We used this transgenic line in an unbiased multiplex phosphoproteomic screen. Several hits were identified and validated as direct PLK4 substrates by in vitro kinase assays. Among them, we confirmed Ser-78 in centrosomal protein 131 (CEP131, also known as AZI1) as a direct substrate of PLK4. Using immunofluorescence microscopy, we observed that although PLK4-mediated phosphorylation of Ser-78 is dispensable for CEP131 localization, ciliogenesis, and centriole duplication, it is essential for maintaining the integrity of centriolar satellites. We also found that PLK4 inhibition or use of a nonphosphorylatable CEP131 variant results in dispersed centriolar satellites. Moreover, replacement of endogenous WT CEP131 with an S78D phosphomimetic variant promoted aggregation of centriolar satellites. We conclude that PLK4 phosphorylates CEP131 at Ser-78 to maintain centriolar satellite integrity.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Centríolos/metabolismo , Proteínas dos Microtúbulos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Ciclo Celular/genética , Centríolos/genética , Proteínas do Citoesqueleto , Células HeLa , Humanos , Proteínas dos Microtúbulos/genética , Fosforilação , Proteínas Serina-Treonina Quinases/genética
15.
PLoS Genet ; 13(1): e1006511, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28081137

RESUMO

During cytokinesis, a contractile ring generates the constricting force to divide a cell into two daughters. This ring is composed of filamentous actin and the motor protein myosin, along with additional structural and regulatory proteins, including anillin. Anillin is a required scaffold protein that links the actomyosin ring to membrane and its organizer, RhoA. However, the molecular basis for timely action of anillin at cytokinesis remains obscure. Here, we find that phosphorylation regulates efficient recruitment of human anillin to the equatorial membrane. Anillin is highly phosphorylated in mitosis, and is a substrate for mitotic kinases. We surveyed function of 46 residues on anillin previously found to be phosphorylated in human cells to identify those required for cytokinesis. Among these sites, we identified S635 as a key site mediating cytokinesis. Preventing S635 phosphorylation adjacent to the AH domain disrupts anillin concentration at the equatorial cortex at anaphase, whereas a phosphomimetic mutant, S635D, partially restores this localization. Time-lapse videomicroscopy reveals impaired recruitment of S635A anillin to equatorial membrane and a transient unstable furrow followed by ultimate failure in cytokinesis. A phosphospecific antibody confirms phosphorylation at S635 in late cytokinesis, although it does not detect phosphorylation in early cytokinesis, possibly due to adjacent Y634 phosphorylation. Together, these findings reveal that anillin recruitment to the equatorial cortex at anaphase onset is enhanced by phosphorylation and promotes successful cytokinesis.


Assuntos
Membrana Celular/metabolismo , Citocinese , Proteínas dos Microfilamentos/metabolismo , Processamento de Proteína Pós-Traducional , Células HeLa , Humanos , Proteínas dos Microfilamentos/química , Proteínas dos Microfilamentos/genética , Mutação , Fosforilação
16.
Cancer ; 125(6): 1000-1007, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30690714

RESUMO

BACKGROUND: Survivorship care plans (SCPs) and care-planning sessions have been recommended for over a decade, yet evidence for their benefit remains mixed. In a randomized trial, changes in survivor knowledge and satisfaction before and after the receipt of an SCP were assessed. METHODS: Patients with breast cancer who had completed curative-intent treatment were randomized to immediate versus delayed receipt of an individualized SCP. All participants completed the modified Wisconsin Survey of Cancer Diagnosis and Management in Breast Cancer and the Preparing for Life As a New Survivor survey to assess individual knowledge about cancer diagnosis, treatment, side effects, and follow-up as well as satisfaction with communication and care coordination. Surveys were completed at baseline, at 4 weeks (before delayed receipt), and again at 12 weeks (after all participants had received SCPs); the primary outcome was change in knowledge at 4 weeks. RESULTS: In total, 127 eligible women were randomized. An improvement in individual knowledge was observed between baseline and week 12 for both arms combined (+1.6; 95% confidence interval, 0.9-2.3; P < .001). There was no statistically significant difference in the change in knowledge from baseline through week 4 between the arms. No significant change occurred for satisfaction scores over time. CONCLUSIONS: This randomized trial of immediate versus delayed SCP receipt demonstrated a small improvement (4%) in survivor knowledge. However, this improvement did not appear to be related to SCP provision. The authors hypothesized that the improvement was because of repeated administration of the knowledge survey. If improved survivor knowledge is a goal, then strategies beyond the 1-time provision and review of an SCP should be explored.


Assuntos
Neoplasias da Mama/terapia , Sobreviventes de Câncer/psicologia , Satisfação do Paciente/estatística & dados numéricos , Medicina de Precisão/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Continuidade da Assistência ao Paciente , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente
17.
BMC Med Educ ; 19(1): 89, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30917818

RESUMO

BACKGROUND: Dual degree program MD/PhD candidates typically train extensively in basic science research and in clinical medicine, but often receive little formal experience or mentorship in clinical and translational research. METHODS: To address this educational and curricular gap, the University of Wisconsin Medical Scientist Training Program partnered with the University of Wisconsin Institute for Clinical and Translational Research to create a new physician-scientist preceptorship in clinical and translational research. This six-week apprentice-style learning experience-guided by a physician-scientist faculty mentor-integrates both clinical work and a translational research project, providing early exposure and hands-on experience with clinically oriented research and the integrated career of a physician-scientist. Five years following implementation, we retrospectively surveyed students and faculty members to determine the outcomes of this preceptorship. RESULTS: Over five years, 38 students and 36 faculty members participated in the physician-scientist preceptorship. Based on student self-assessments (n = 29, response rate 76%), the course enhanced competency in conducting translational research and understanding regulation of clinical research among other skills. Mentor assessments (n = 17, response rate 47%) supported the value of the preceptorship in these same areas. Based on work during the preceptorship, half of the students produced a peer-reviewed publication or a meeting abstract. At least eleven peer-reviewed manuscripts were generated. The preceptorship also provided a structure for physician-scientist mentorship in the students' clinical specialty of choice. CONCLUSION: The physician-scientist preceptorship provides a new curricular model to address the gap of clinical research training and provides for mentorship of physician-scientists during medical school. Future work will assess the long-term impact of this course on physician-scientist career trajectories.


Assuntos
Medicina Clínica/educação , Medicina Interna/educação , Preceptoria , Estudantes de Medicina/estatística & dados numéricos , Pesquisa Translacional Biomédica , Escolha da Profissão , Feminino , Humanos , Masculino , Mentores , Avaliação de Programas e Projetos de Saúde , Melhoria de Qualidade , Estudos Retrospectivos , Estudantes de Medicina/psicologia , Pesquisa Translacional Biomédica/educação , Adulto Jovem
18.
Nat Chem Biol ; 12(6): 411-8, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27043190

RESUMO

Protein kinase signaling along the kinetochore-centromere axis is crucial to assure mitotic fidelity, yet the details of its spatial coordination are obscure. Here, we examined how pools of human Polo-like kinase 1 (Plk1) within this axis control signaling events to elicit mitotic functions. To do this, we restricted active Plk1 to discrete subcompartments within the kinetochore-centromere axis using chemical genetics and decoded functional and phosphoproteomic signatures of each. We observe distinct phosphoproteomic and functional roles, suggesting that Plk1 exists and functions in discrete pools along this axis. Deep within the centromere, Plk1 operates to assure proper chromosome alignment and segregation. Thus, Plk1 at the kinetochore is a conglomerate of an observable bulk pool coupled with additional functional pools below the threshold of microscopic detection or resolution. Although complex, this multiplicity of locales provides an opportunity to decouple functional and phosphoproteomic signatures for a comprehensive understanding of Plk1's kinetochore functions.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Centrômero/metabolismo , Cinetocoros/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Humanos , Quinase 1 Polo-Like
19.
Invest New Drugs ; 35(1): 87-94, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27826831

RESUMO

Introduction Suppressing both androgens and estrogens may circumvent hormone receptor resistance in breast cancer by reducing androgen receptor stimulation. Selective inhibition of the 17, 20-lyase enzyme by orteronel leads to decreased androgen production in men and would be anticipated to reduce estrogen and androgen production in women. Thus, we conducted a phase 1b study of orteronel in postmenopausal women with hormone-receptor positive (HR+) metastatic breast cancer. Methods The primary objective was to identify the recommended phase 2 dose (R2PD) of orteronel in women; escalation was via standard 3 + 3 design. The initial dose was 300 mg BID and escalated to 400 mg BID. Cycle length was 28 days. Enrolled patients had HR+ metastatic breast cancer and were evaluated every 8 weeks for disease progression. Results Eight heavily pre-treated women enrolled [median age: 57 yo (range 47-73)]. Four received 300 mg BID at dose level 1; 4 received 400 mg BID at dose level 2. No dose limiting toxicities (DLTs) were observed. Adverse events (AE) at least possibly related to orteronel included grade 1-2 nausea (n = 4) and bone pain (n = 3), and grade 1 hypokalemia, hot flashes, myalgia and AST elevation (n = 2). The only grade 3 AE was hypertension (n = 2) with 8 patients receiving 34 cycles of treatment. No objective responses were seen; clinical benefit was seen in 2 patients with stable disease for more than 6 months. Serum estrogens and testosterone were suppressed from baseline on both doses of orteronel. Conclusions Orteronel 400 mg BID is well tolerated in postmenopausal women, and significantly suppresses serum estrogens and testosterone. Clinical benefit was seen among heavily pretreated postmenopausal women with HR+ metastatic breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Imidazóis/uso terapêutico , Naftalenos/uso terapêutico , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Idoso , Neoplasias da Mama/sangue , Neoplasias da Mama/metabolismo , Feminino , Hormônios/sangue , Humanos , Imidazóis/efeitos adversos , Imidazóis/farmacologia , Pessoa de Meia-Idade , Naftalenos/efeitos adversos , Naftalenos/farmacologia , Pós-Menopausa , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Resultado do Tratamento
20.
BMC Cancer ; 17(1): 866, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29258457

RESUMO

BACKGROUND: Capecitabine is an oral prodrug of fluorouracil, which is a common agent used in the management of many solid tumor malignancies. Dermatologic reaction is common with various chemotherapy agents but is not commonly reported in the use of capecitabine. When adverse reactions of rashes occur, the offending agent is typically removed. We report here an unusual case of photosensitive lichenoid rash due to capecitabine which is managed conservatively without major alteration in treatment. CASE PRESENTATION: Seventy-three year old female with a diagnosis of stage IV breast cancer undergoing management with capecitabine presents with a rash during the summer months that is biopsy proven to be lichenoid photosensitive rash with likely offending agent being capecitabine. Her treatment was initially held despite having response to treatment, started on topical steroids after evaluation by dermatology. Given her response to treatment, drug was resumed with instructions to use sun precaution, sunscreen, and to complete course of topical steroids until rash resolution. CONCLUSION: Drug-related rashes tend to lead to disruptions or alterations in treatments of malignancies, despite responses. Given the wide use of capecitabine in many different solid tumors, it is important to recognize this photosensitive related skin rash and to initiate appropriate precautions of sun safety and topical steroids to allow minimal disruptions in therapy and continue use of capecitabine.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Capecitabina/efeitos adversos , Erupções Liquenoides/tratamento farmacológico , Transtornos de Fotossensibilidade/tratamento farmacológico , Administração Tópica , Idoso , Neoplasias da Mama/patologia , Capecitabina/administração & dosagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Erupções Liquenoides/induzido quimicamente , Erupções Liquenoides/patologia , Transtornos de Fotossensibilidade/induzido quimicamente , Transtornos de Fotossensibilidade/patologia , Esteroides/administração & dosagem
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