RESUMO
RAD51 is the central eukaryotic recombinase required for meiotic recombination and mitotic repair of double-strand DNA breaks (DSBs)1,2. However, the mechanism by which RAD51 functions at DSB sites in chromatin has remained elusive. Here we report the cryo-electron microscopy structures of human RAD51-nucleosome complexes, in which RAD51 forms ring and filament conformations. In the ring forms, the N-terminal lobe domains (NLDs) of RAD51 protomers are aligned on the outside of the RAD51 ring, and directly bind to the nucleosomal DNA. The nucleosomal linker DNA that contains the DSB site is recognized by the L1 and L2 loops-active centres that face the central hole of the RAD51 ring. In the filament form, the nucleosomal DNA is peeled by the RAD51 filament extension, and the NLDs of RAD51 protomers proximal to the nucleosome bind to the remaining nucleosomal DNA and histones. Mutations that affect nucleosome-binding residues of the RAD51 NLD decrease nucleosome binding, but barely affect DNA binding in vitro. Consistently, yeast Rad51 mutants with the corresponding mutations are substantially defective in DNA repair in vivo. These results reveal an unexpected function of the RAD51 NLD, and explain the mechanism by which RAD51 associates with nucleosomes, recognizes DSBs and forms the active filament in chromatin.
Assuntos
Microscopia Crioeletrônica , Quebras de DNA de Cadeia Dupla , Nucleossomos , Rad51 Recombinase , Proteínas de Saccharomyces cerevisiae , Humanos , DNA/química , DNA/metabolismo , DNA/ultraestrutura , Reparo do DNA/genética , Nucleossomos/química , Nucleossomos/metabolismo , Nucleossomos/ultraestrutura , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Rad51 Recombinase/química , Rad51 Recombinase/metabolismo , Rad51 Recombinase/ultraestrutura , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Mutação , Domínios Proteicos , Histonas/química , Histonas/metabolismo , Histonas/ultraestrutura , Ligação ProteicaRESUMO
PURPOSE: c-Jun N-terminal kinases (JNKs) comprise a subfamily of mitogen-activated protein kinases (MAPKs). The JNK group is known to be activated by a variety of stimuli. However, the molecular mechanism underlying heat-induced JNK activation is largely unknown. The aim of this study was to clarify how JNK activity is stimulated by heat. METHODS AND MATERIALS: The expression levels of various MAPK members in HeLa cells, with or without hyperthermia treatment, were evaluated via western blotting. The kinase activity of MAPK members was assessed through in vitro kinase assays. Cell death was assessed in the absence or presence of siRNAs targeting MAPK-related members. RESULTS: Hyperthermia decreased the levels of MAP3Ks, such as ASK1 and MLK3 which are JNK kinase kinase members, but not those of the downstream MAP2K/SEK1 and MAPK/JNK. Despite the reduced or transient phosphorylation of ASK1, MLK3, or SEK1, downstream JNK was phosphorylated in a temperature-dependent manner. In vitro kinase assays demonstrated that heat did not directly stimulate SEK1 or JNK. However, the expression levels of DUSP16, a JNK phosphatase, were decreased upon hyperthermia treatment. DUSP16 knockdown enhanced the heat-induced activation of ASK1-SEK1-JNK pathway and apoptosis. CONCLUSION: JNK was activated in a temperature-dependent manner despite reduced or transient phosphorylation of the upstream MAP3K and MAP2K. Hyperthermia-induced degradation of DUSP16 may induce activation of the ASK1-SEK1-JNK pathway and subsequent apoptosis.
Assuntos
Hipertermia Induzida , Sistema de Sinalização das MAP Quinases , Humanos , Células HeLa , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Apoptose/fisiologiaRESUMO
OBJECTIVE: To determine the effectiveness of a web-based educational program regarding local healthcare planning by public health nurses (PHNs) in Japan. DESIGN: A single-blind randomized controlled trial. SAMPLE: Full-time PHNs working for local governments across Japan. MEASUREMENTS: The primary outcome was nurses' self-perception of competencies in public health policy. The secondary outcome was self-perception of knowledge, skills, and perspectives regarding local healthcare planning. We analyzed intergroup differences using the intention-to-treat principle and the Mann-Whitney U-test. INTERVENTION: The intervention group received six web-based learning modules including substantial knowledge and skills regarding local healthcare planning based on the analysis, design, development, implementation, and evaluation model and adult learning theory. RESULTS: Totally, 273 PHNs registered, and 38 were excluded without completing the baseline survey; 235 were randomly allocated to either the intervention (n = 118) or control (n = 117) groups. Sixty-four participants in the intervention group completed the program. Over 70% of the participants lacked opportunities to learn about local healthcare planning. The intervention group showed significant improvement in self-perception of competencies, knowledge, and skills regarding local healthcare planning, except for items related to evaluation. CONCLUSIONS: The web-based learning program effectively improved participants' self-perception of competencies in local healthcare planning.
Assuntos
Enfermeiros de Saúde Pública , Adulto , Humanos , Método Simples-Cego , Estudantes , Atenção à Saúde , InternetRESUMO
ObjectiveãTo clarify the actual state of activities conducted by public health nurses (PHNs) during normal times and assess factors related to the implementation of such activities for the promotion of residents' mutual support during disasters, across different municipalities in Japan.MethodsãWe conducted a nationwide cross-sectional self-report questionnaire survey of PHNs in 1,463 municipalities. The questionnaires included descriptions of municipalities, activities related to disaster prevention and the rationale for them, and the details of activities that were being conducted to promote residents' mutual support in times of disaster. We conducted multiple logistic analyses to examine the associated factors.ResultsãWe analyzed 535 responses (valid response rate of 36.6%). The proportion of municipalities in which oriented district activity systems and oriented business activity systems were used jointly by PHNs was 81.7%. The proportion of municipalities in which PHNs participated in the formulation of regional disaster prevention plans was 31.6%. "Individual support" would be implemented for persons requiring support in evacuation activities in 41.7% of municipalities; "cooperative support for community organizations," in 34.8%; and other "activities for the purpose of residents' mutual support," in 29.9%. Reasons for not implementing such measures included "outside the division of duties" and "having no contact with residents' organizations." Logistic regression analyses showed that the oriented district activity system, participation of PHNs in the formulation of regional disaster prevention plans, and preparation of an activity manual on disaster countermeasures for PHNs were significantly associated with the performance of activities during normal times for promotion of residents' mutual support during disasters.ConclusionãOur findings clarified that the PHNs' activities during normal times for the promotion of residents' mutual support during disasters were not carried out sufficiently. It is important to review activities according to the district, to ensure supervisory PHNs play a greater role, to provide external support to municipalities for the participation of PHNs in the formulation of regional disaster prevention plans, and to prepare an activity manual on disaster countermeasures for PHNs.
Assuntos
Desastres , Enfermeiros de Saúde Pública , Cidades , Estudos Transversais , Humanos , Japão , Inquéritos e QuestionáriosRESUMO
The synaptonemal complex (SC) is a proteinaceous structure that is transiently formed during meiosis to promote homologous recombination between maternal and paternal chromosomes. As this structure is required only for meiotic recombination, the proteins constituting the complex are almost undetectable in normal somatic cells, but they can be expressed under the conditions in which the transcriptional machinery is deregulated. Accumulating evidence indicates that they are epigenetically expressed in cancers of various origin. Not surprisingly, in contrast to their meiotic roles, the somatic roles of the SC proteins remain to be investigated. However, it has recently been reported that SYCP3 and SYCE2 control DNA double-strand break repair negatively and positively, respectively, suggesting that the ectopic expression of the SC proteins in somatic cells could be associated with the maintenance of genomic instability. Thus, it is highly likely that the investigation of the somatic roles of the SC proteins would improve our understanding of the mechanisms underlying tumor development.
Assuntos
Epigênese Genética , Instabilidade Genômica , Neoplasias/genética , Complexo Sinaptonêmico/metabolismo , Animais , Proteínas de Ciclo Celular/metabolismo , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/metabolismo , Humanos , Camundongos , Modelos Animais , Proteínas Nucleares/metabolismo , Reparo de DNA por RecombinaçãoRESUMO
AIM: To identify self-reported competencies of public health nurses for reflecting community healthcare needs in local healthcare plans. DESIGN: We conducted a nationwide cross-sectional survey in Japan from October 7-November 30, 2019. METHODS: We sent 2,185 self-reported questionnaires to public health nurses in Japan who had developed a local healthcare plan since 2013. Self-reported questionnaires included questions regarding demographic data and the reflection of community healthcare needs in local healthcare plans, and the involvement in local healthcare planning. RESULTS: We analysed 1,042 questionnaires: 651 (62.5%) were from public health nurses who reported that they elicited and shared community views to be reflected for purposes of local healthcare planning (the reflecting group), and 391 (37.5%) of the remaining public health nurses who reported that they did not do so (the non-reflecting group). The logistic regression analysis revealed that public health nurses in the reflecting group were more likely to be in a managerial position, have colleagues who played an active role in healthcare planning, conduct a questionnaire survey, engage in group work, participate in a municipal healthcare planning committee with community-dwelling people, and identify the opinions of the professional organizations. CONCLUSIONS: Identifying community healthcare needs through collaboration with community-dwelling people and professional organizations should be essential competencies for public health nurses (the reflecting group) in developing needs-oriented local healthcare plans. IMPACT: Identification of their related competencies for developing a needs-oriented local healthcare plan as an upstream strategy to mitigate the prevalence of health inequities in each community.
Assuntos
Enfermeiros de Saúde Pública , Estudos Transversais , Atenção à Saúde , Humanos , Japão , Autorrelato , Inquéritos e QuestionáriosRESUMO
ObjectiveãThe aim of this study was to elucidate the status of health-care, medical, and welfare planning (hereafter, "planning")-in which public health nurses (PHNs) had participated-and the factors associated with community collaboration in the implementation phase. Additionally, suggestions regarding health activities that would contribute to improving the entire community's health level were obtained.MethodsãThe Plan-Do-Check-Act (PDCA) cycle was the conceptual framework for this study, and the focus was the implementation phase of the plan (i.e., corresponding to the "Do" phase). Survey items were part of the "Plan" phase and identified the extent to which PHNs collaborated with community-dwellers in implementation, their demographics, their participation in the planning process, organizational factors, and the strategies used in the planning phase. The participants were full-time PHNs working in local governments who had participated in the planning process since 2013 (when the guidelines for PHNs' practices were published). A nationwide, cross-sectional survey was conducted in Japan with 2,185 PHNs from 220 regions (36 prefectures, 41 cities with public health centers, and 153 municipalities) who expressed the willingness to participate in this study. A binomial logistic regression analysis was conducted to examine the association between community collaboration and the independent variables.ResultsãA total of 1,281 answers (a 58.6% response rate) were received. Ultimately, 1,028 (a 47.0% valid response rate) were analyzed; exclusions were 203 for no experience in health care planning since 2013 and 50 with missing values. There were 125 (12.2%) PHNs who answered that they "did not collaborate with the community-dwellers at all," 293 (28.5%) who answered that they "did not collaborate with them much," 482 (46.9%) who replied that they "collaborated with them a little," and 128 (12.4%) who responded that they "collaborated with them a lot." The binomial logistic regression analysis showed that the following were associated with PHNs' collaboration with the community: being in a managerial position, having experience developing a health promotion plan, conducting a questionnaire survey or group work, as well as participating in municipal health planning committees with community-dwellers, utilizing research evidence, identifying target groups, and managing the plan's progress.ConclusionãFrom the planning phase, PHNs must collaborate with community residents and reflect their voices so that the formulated plan will help resolve medium to long-term issues in the community related to health and life.
Assuntos
Enfermeiros de Saúde Pública , Enfermagem em Saúde Pública , Estudos Transversais , Atenção à Saúde , Promoção da Saúde , HumanosRESUMO
OBJECTIVES: To evaluate the impact of web-based learning modules for health program planning competency, recognition, knowledge and skills among mid-level public health nurses (PHNs). DESIGN: Parallel-group randomized controlled trial. SAMPLE: During 2018, 244 Japanese PHNs were eligible as participants with 5-20 years experiences as a PHN were randomly allocated to the intervention (n = 121) or control group (n = 123). MEASUREMENTS: The outcome was assessed using the Competency Measurement of Creativity for PHNs (CMC) and 26 questions about recognition, knowledge, and skills for health program planning. INTERVENTIONS: Eight web-based modules. RESULTS: No significant differences in CMC scores between the control and intervention groups at base line and post-intervention. By contrast, significant differences in total score of the 26 items of knowledge and skills. In an exploratory analysis, there was a significant difference identified in CMC scores in the demographic of post graduate training in program planning at base line and post-intervention. (p = .034). CONCLUSIONS: The findings suggested that web-based learning with flexibility in terms of time and location would improve competency, skills and knowledge of health program planning among mid-level PHNs.
Assuntos
Promoção da Saúde/métodos , Internet , Enfermeiros de Saúde Pública/educação , Adulto , Humanos , Japão , Masculino , Desenvolvimento de ProgramasRESUMO
OBJECTIVE: To evaluate the effectiveness of an education program for mid-level Japanese public health nurses (PHNs) to improve their competencies in program planning, which will fulfill community health needs. DESIGN: Randomized control trial. SAMPLE: During 2017, 103 PHNs with 5-20 years of PHN work experience in Japan were enrolled and randomly allocated to the intervention (n = 51) or control group (n = 52). MEASUREMENTS: The primary outcome measured competency in program planning based on Competency Measurement of Creativity for PHNs (CMC), knowledge, and skills regarding program planning. INTERVENTION: Six web-based learning modules followed by two face-to-face group sessions. RESULTS: The PHN participants averaged about 12 years of experience. In the intervention group, 25 PHNs completed all modules (49.0%). Post intervention, there were no statistically significant differences among any between-group CMC scores. However, the intervention group's CMC 3 score was significantly higher than that of the control group of ≥12 years of experience. Total knowledge and skill scores also improved significantly in the intervention group compared with the control group. CONCLUSIONS: The results suggest that PHNs with ≥12 years of experience are a suitable target of this educational program, and should play a key role in program planning.
Assuntos
Enfermeiros de Saúde Pública/educação , Desenvolvimento de Programas/métodos , Enfermagem em Saúde Pública/educação , Adulto , Feminino , Humanos , Japão , MasculinoRESUMO
The patient was a 57-year-old woman with Castleman's disease. The follow-up CT scans obtained during the treatment of Castleman's disease, detected a 15mm nodule in the right breast AC area, and the patient was diagnosed with breast cancer. Lymphadenopathy was noted on both sides of the axilla; however, it was considered to be due to Catsleman's disease. Mastectomy and sentinel lymph node biopsy were performed with preoperative diagnosis of cT1cN0M0, cStage â . Rapid diagnosis of the sentinel lymph node during the operation showed a metastatic tumor measuring 3mm and axillary dissection was performed. However, no metastasis was found in the dissected lymph node, which was, therefore, considered as an enlargement due to Castleman's disease.
Assuntos
Neoplasias da Mama , Hiperplasia do Linfonodo Gigante , Axila , Neoplasias da Mama/complicações , Neoplasias da Mama/cirurgia , Hiperplasia do Linfonodo Gigante/complicações , Feminino , Humanos , Excisão de Linfonodo , Linfonodos , Mastectomia , Pessoa de Meia-Idade , Biópsia de Linfonodo SentinelaRESUMO
The synaptonemal complex is a higher-ordered proteinaceous architecture formed between homologous chromosomes. SYCP3 is a major component of the lateral/axial elements in the synaptonemal complex and is essential for meiotic recombination. Previous genetic studies showed that SYCP3 functions in meiotic homologous recombination biased to interhomologous chromosomes, by regulating the strand invasion activities of the RAD51 and DMC1 recombinases. However, the mechanism by which SYCP3 regulates RAD51- and DMC1-mediated strand invasion remains elusive. In this study, we found that SYCP3 significantly suppresses the RAD51-mediated, but not the DMC1-mediated, strand invasion reaction by competing with HOP2-MND1, which is an activator for both RAD51 and DMC1. A SYCP3 mutant with defective RAD51 binding does not inhibit the RAD51-mediated homologous recombination in human cells. Therefore, SYCP3 may promote the DMC1-driven homologous recombination by attenuating the RAD51 activity during meiosis.
Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Recombinação Homóloga , Proteínas Nucleares/metabolismo , Rad51 Recombinase/metabolismo , Células HeLa , Humanos , Mutação , Proteínas Nucleares/genética , Ligação Proteica , Transativadores/metabolismoRESUMO
Erdheim-Chester disease is a rare histiocytosis with insufficient clinical data. To clarify the clinical features and prognostic factors of Erdheim-Chester disease, we conducted a nationwide survey to collect the detailed data of 44 patients with Erdheim-Chester disease in Japan. The median age of onset of the participants was 51 (range: 23-76) years, and the median number of involved organs per patient was 4 (range: 1-11). The existence of central nervous system disease was correlated with older age (P=0.033), the presence of cardiovascular lesions (P=0.015), and an increased number of involved organs (P=0.0042). The median survival from the onset was 10.4 years, and >3.0 mg/dL C-reactive protein level at onset was associated with worse outcome (median survival, 14.6 vs. 7.4 years; P=0.0016). In a multivariate analysis, age >60 years (hazard ratio, 25.9; 95% confidence interval, 2.82-237; P=0.0040) and the presence of digestive organ involvement (hazard ratio, 4.74; 95% confidence interval, 1.05-21.4; P=0.043) were correlated with worse survival. Fourteen patients had available histological samples of Erdheim- Chester disease lesions. BRAFV600E mutation was detected in 11 patients (78%) by Sanger sequencing. A correlation between BRAF mutation status and clinical factors was not observed. Our study revealed that age and digestive organ involvement influence the outcome of Erdheim-Chester disease patients, and an inflammatory marker, such as C-reactive protein, might reflect the activity of this inflammatory myeloid neoplasm.
Assuntos
Doença de Erdheim-Chester/genética , Doença de Erdheim-Chester/mortalidade , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas B-raf/genética , Adulto , Fatores Etários , Idoso , Substituição de Aminoácidos , Intervalo Livre de Doença , Doença de Erdheim-Chester/patologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Taxa de SobrevidaRESUMO
BACKGROUND: Developing health services is a key strategy for improving the community health provided by public health nurses. However, an effective educational program for improving their skills in planning such services has not been developed. To describe our program and its evaluation protocol for the education of middle-level public health nurses to improve their skills in developing new health services to fulfil community health needs in Japan. METHODS: In this randomized control trial, eligible participants in Japan will be randomly allocated to an intervention group and a control wait-list group. We will provide 8 modules of web-based learning for public health nurses from July to October 2018. To ensure fairness of educational opportunity, the wait-list group will participate in the same program as the intervention group after collection of follow-up data of the intervention group. The primary outcomes will be evaluated using the scale of competency measurement of creativity for public health nurses at baseline, immediately after the intervention. Secondary outcomes will be knowledge and performance regarding program development of public health nurses. DISCUSSION: This study will enable the analysis of the effects of the educational program on public health nurses for improving their competency to develop new health services for fulfilling community health needs and enriching health care systems. TRIAL REGISTRATION: We registered our study protocol to the University hospital Medical Information Network- Clinical Trials Registry approved by International Committee of Medical Journal Editors (No. UMIN000032176, April, 2018).
RESUMO
Radiation therapy is a key therapeutic strategy for endometrial carcinomas. However, biomarkers that predict radiosensitivity and drugs to enhance this sensitivity have not yet been established. We aimed to investigate the roles of TP53 and MAPK/PI3K pathways in endometrial carcinomas and to identify appropriate radiosensitizing therapeutics. D10 values (the irradiating dose required to reduce a cell population by 90%) were determined in eight endometrial cancer cell lines with known mutational statuses for TP53, PIK3CA, and KRAS. Cells were exposed to ionizing radiation (2-6Gy) and either a dual PI3K/mTOR inhibitor (NVP-BEZ235) or a MEK inhibitor (UO126), and their radiosensitizing effects were evaluated using clonogenic assays. The effects of silencing hypoxia-inducible factor-1 α (HIF-1α) expression with small interfering RNAs (siRNAs) were evaluated following exposure to ionizing radiation (2-3Gy). D10 values ranged from 2.0 to 3.1Gy in three cell lines expressing wild-type TP53 or from 3.3 to more than 6.0Gy in five cell lines expressing mutant TP53. NVP-BEZ235, but not UO126, significantly improved radiosensitivity through the suppression of HIF-1α/vascular endothelial growth factor-A expression. HIF-1α silencing significantly increased the induction of the sub-G1 population by ionizing radiation. Our study data suggest that TP53 mutation and PI3K pathway activation enhances radioresistance in endometrial carcinomas and that targeting the PI3K/mTOR or HIF-1α pathways could improve radiosensitivity.
Assuntos
Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/radioterapia , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Inibidores de Fosfoinositídeo-3 Quinase , Serina-Treonina Quinases TOR/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Butadienos/farmacologia , Carcinoma Endometrioide/tratamento farmacológico , Carcinoma Endometrioide/radioterapia , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Feminino , Genes p53 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imidazóis/farmacologia , Nitrilas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Quinolinas/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Cancer chemotherapy and radiotherapy are designed to kill cancer cells mostly by inducing DNA damage. DNA damage is normally recognized and repaired by the intrinsic DNA damage response machinery. If the damaged lesions are successfully repaired, the cells will survive. In order to specifically and effectively kill cancer cells by therapies that induce DNA damage, it is important to take advantage of specific abnormalities in the DNA damage response machinery that are present in cancer cells but not in normal cells. Such properties of cancer cells can provide biomarkers or targets for sensitization. For example, defects or upregulation of the specific pathways that recognize or repair specific types of DNA damage can serve as biomarkers of favorable or poor response to therapies that induce such types of DNA damage. Inhibition of a DNA damage response pathway may enhance the therapeutic effects in combination with the DNA-damaging agents. Moreover, it may also be useful as a monotherapy when it achieves synthetic lethality, in which inhibition of a complementary DNA damage response pathway selectively kills cancer cells that have a defect in a particular DNA repair pathway. The most striking application of this strategy is the treatment of cancers deficient in homologous recombination by poly(ADP-ribose) polymerase inhibitors. In this review, we describe the impact of targeting the cancer-specific aberrations in the DNA damage response by explaining how these treatment strategies are currently being evaluated in preclinical or clinical trials.
Assuntos
Dano ao DNA/genética , Reparo do DNA/genética , Neoplasias/genética , Inibidores de Poli(ADP-Ribose) Polimerases , Inibidores Enzimáticos/uso terapêutico , Recombinação Homóloga , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Transdução de SinaisRESUMO
BACKGROUND: PTEN inactivation is the most frequent genetic aberration in endometrial cancer. One of the phosphatase-independent roles of PTEN is associated with homologous recombination (HR) in nucleus. Poly (ADP-ribose) polymerase (PARP) plays key roles in the repair of DNA single-strand breaks, and a PARP inhibitor induces synthetic lethality in cancer cells with HR deficiency. We examined the anti-tumor activity of olaparib, a PARP inhibitor, and its correlation between the sensitivity and status of PTEN in endometrial cancer cell lines. METHODS: The response to olaparib was evaluated using a clonogenic assay with SF50 values (concentration to inhibit cell survival to 50%) in 16 endometrial cancer cell lines. The effects of PTEN on the sensitivity to olaparib and ionizing radiation (IR) exposure were compared between parental HEC-6 (PTEN-null) and HEC-6 PTEN + (stably expressing wild-type PTEN) cells by clonogenic assay, foci formation of RAD51 and γH2AX, and induction of cleaved PARP. The effects of siRNA to PTEN were analyzed in cells with wild-type PTEN. RESULTS: The SF50 values were 100 nM or less in four (25%: sensitive) cell lines; whereas, SF50 values were 1,000 nM or more in four (25%: resistant) cell lines. PTEN mutations were not associated with sensitivity to olaparib (Mutant [n = 12]: 746 ± 838 nM; Wild-type [n = 4]: 215 ± 85 nM, p = 0.26 by Student's t test). RAD51 expression was observed broadly and was not associated with PTEN status in the 16 cell lines. The number of colonies in the clonogenic assay, the foci formation of RAD51 and γH2AX, and the induction of apoptosis were not affected by PTEN introduction in the HEC-6 PTEN + cells. The expression level of nuclear PTEN was not elevated within 24 h following IR in the HEC-6-PTEN + cells. In addition, knocking down PTEN by siRNA did not alter the sensitivity to olaparib in 2 cell lines with wild-type PTEN. CONCLUSIONS: Our results suggest that olaparib, a PARP inhibitor, is effective on certain endometrial cancer cell lines. Inactivation of PTEN might not affect the DNA repair function. Predictive biomarkers are warranted to utilize olaparib in endometrial cancer.
Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias do Endométrio/tratamento farmacológico , Ftalazinas/farmacologia , Piperazinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Humanos , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Radiação IonizanteRESUMO
The meiosis-specific synaptonemal complex protein SYCP3 has been reported to be aberrantly expressed in tumours. However, in contrast to its well-defined function in meiosis, its possible role in mitotic cells is entirely unknown. Here, we show that SYCP3 is expressed in a range of primary tumours and that it impairs chromosomal integrity in mitotic cells. Expression of SYCP3 inhibits the homologous recombination (HR) pathway mediated by RAD51, inducing hypersensitivity to DNA-damaging agents such as a poly(ADP-ribose) polymerase (PARP) inhibitor and chromosomal instability. SYCP3 forms a complex with BRCA2 and inhibits its role in HR. These findings highlight a new mechanism for chromosomal instability in cancer and extend the range of PARP-inhibitor sensitive tumours to those expressing SYCP3.
Assuntos
Proteína BRCA2/metabolismo , Recombinação Homóloga , Mitose/genética , Proteínas Nucleares/metabolismo , Aneuploidia , Proteínas de Ciclo Celular , Instabilidade Cromossômica , Dano ao DNA/efeitos da radiação , Reparo do DNA/genética , Reparo do DNA/efeitos da radiação , Proteínas de Ligação a DNA , Resistencia a Medicamentos Antineoplásicos/genética , Inativação Gênica , Células Hep G2 , Humanos , Proteínas Nucleares/genética , Inibidores de Poli(ADP-Ribose) Polimerases , Ligação Proteica , Rad51 Recombinase/metabolismo , Tolerância a Radiação/genética , Troca de Cromátide IrmãRESUMO
Chromosomes adopt specific conformations to regulate various cellular processes. A well-documented chromosome configuration is the highly compacted chromosome structure during metaphase. More regional chromatin conformations have also been reported, including topologically associated domains encompassing mega-bases of DNA and local chromatin loops formed by kilo-bases of DNA. In this review, we discuss the changes in chromatin conformation taking place between somatic and meiotic cells, with a special focus on the establishment of a proteinaceous structure, called the chromosome axis, at the beginning of meiosis. The chromosome axis is essential to support key meiotic processes such as chromosome pairing, homologous recombination, and balanced chromosome segregation to transition from a diploid to a haploid stage. We review the role of the chromosome axis in meiotic chromatin organization and provide a detailed description of its protein composition. We also review the conserved and distinct roles between species of axis proteins in meiotic recombination, which is a major factor contributing to the creation of genetic diversity and genome evolution. Finally, we discuss situations where the chromosome axis is deregulated and evaluate the effects on genome integrity and the consequences from protein deregulation in meiocytes exposed to heat stress, and aberrant expression of genes encoding axis proteins in mammalian somatic cells associated with certain types of cancers.
Assuntos
Neoplasias , Complexo Sinaptonêmico , Animais , Meiose/genética , Pareamento Cromossômico , Cromatina/genética , Neoplasias/genética , Mamíferos/genéticaRESUMO
OBJECTIVE: This study investigated the association between receiving off-the-job training and the involvement of public health nurses in local healthcare planning. DESIGN: A nationwide, cross-sectional study design. METHODS: We sent self-report questionnaires to 2,185 public health nurses with experience in developing local healthcare plans in Japan since 2013 and collected information related to three main categories: demographic data, involvement in local healthcare planning and strategies for healthcare planning. RESULTS: We received 1,281 responses (return rate of 58.6%), of which 231 did not meet the inclusion criteria. Thus, we analysed 1,050 valid responses. Among the 1,050 respondents, 496 (47.2%) had received off-the-job training in healthcare planning. A subsequent logistic regression analysis revealed that the following factors were associated with this achievement: holding a managerial position, receiving healthcare planning education at the undergraduate level, having mentors regarding the promotion of it, partially conducting cross-sectional coordination and conducting groupwork with community-dwelling residents.
Assuntos
Administração de Serviços de Saúde , Enfermeiros de Saúde Pública , Humanos , Estudos Transversais , Capacitação em Serviço , Atenção à SaúdeRESUMO
BACKGROUND: Digitalization and information and communication technology (ICT) promote effective, efficient individual and community care. Clinical terminology or taxonomy and its framework visualize individual patients' and nursing interventions' classifications to improve their outcomes and care quality. Public health nurses (PHNs) provide lifelong individual care and community-based activities while developing projects to promote community health. The linkage between these practices and clinical assessment remains tacit. Owing to Japan's lagging digitalization, supervisory PHNs face difficulties in monitoring each department's activities and staff members' performances and competencies. Randomly selected prefectural or municipal PHNs collect data on daily activities and required hours every 3 years. No study has adopted these data for public health nursing care management. PHNs need ICTs to manage their work and improve care quality; it may help identify health needs and suggest best public health nursing practices. OBJECTIVE: We aim to develop and validate an electronic recording and management system for evaluating different public health nursing practice needs, including individual care, community-based activities, and project development, and for determining their best practices. METHODS: We used a 2-phase exploratory sequential design (in Japan) comprising 2 phases. In phase 1, we developed the system's architectural framework and a hypothetical algorithm to determine the need for practice review through a literature review and a panel discussion. We designed a cloud-based practice recording system, including a daily record system and a termly review system. The panels included 3 supervisors who were prior PHNs at the prefectural or municipal government, and 1 was the executive director of the Japanese Nursing Association. The panels agreed that the draft architectural framework and hypothetical algorithm were reasonable. The system was not linked to electronic nursing records to protect patient privacy. Phase 2 validated each item through interviews with supervisory PHNs using a web-based meeting system. A nationwide survey was distributed to supervisory and midcareer PHNs across local governments. RESULTS: This study was funded in March 2022 and approved by all ethics review boards from July to September and November 2022. Data collection was completed in January 2023. Five PHNs participated in the interviews. In the nationwide survey, responses were obtained from 177 local governments of supervisory PHNs and 196 midcareer ones. CONCLUSIONS: This study will reveal PHNs' tacit knowledge about their practices, assess needs for different approaches, and determine best practices. Additionally, this study will promote ICT-based practices in public health nursing. The system will enable PHNs to record their daily activities and share them with their supervisors to reflect on and improve their performance, and the quality of care to promote health equity in community settings. The system will support supervisory PHNs in creating performance benchmarks for their staff and departments to promote evidence-based human resource development and management. TRIAL REGISTRATION: UMIN-ICDR UMIN000049411; https://tinyurl.com/yfvxscfm. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/45342.