Cultural differences in clinical leadership: a qualitative study comparing the attitudes of general dental practitioners from Greater Manchester and Tokyo

BACKGROUND AND AIMS

Leadership has been argued to be a key component in the transformation of services in the United Kingdom and in Japan. In the UK, local professional networks have developed to provide clinician led care in dentistry; working to develop local plans to deliver improvements in the quality of care for patients. In Japan, the remuneration model for dental care has been revised with the aim to improve the service and tackle the current challenges of population health there. The aim of this study was to use semi-structured interviews and thematic analysis to explore general dental practitioners' (GDPs) understanding of the term 'leadership' and determine whether its meaning is culturally bound.

METHODS

Twelve participants were sampled purposively by the research team; identifying GDPs involved in leadership roles from across Greater Manchester and Tokyo. A set of open-ended questions was developed for semi-structured interviews a priori and the interviews continued until saturation. Interviews were recorded, transcribed verbatim and codes were developed into a coding frame for thematic analysis. Representative quotations are provided in the results.

RESULTS

Fourteen codes were identified according to the aims of the study and organised into five overarching themes. 'Leadership as the relationship' was more pronounced among Japanese GDPs, while 'leadership as the individual' was common in GDPs from Greater Manchester. Differences were also found in respect of education and training in leadership. Training was also considered to be important by the GDPs from Japan, while UK GDPs felt leaders were more likely to be influenced by innate qualities. The interdependence of leadership and entrepreneurship was raised by both sets of GDPs.

CONCLUSION

The concept of leadership was considered to be important by GDPs from both Greater Manchester and Tokyo; leadership was seen as providing strategy and direction for a clinical team. However, cultural influences were evident in how this was conceptualised.

Cancer stem cell-related marker expression in lung adenocarcinoma and relevance of histologic subtypes based on IASLC/ATS/ERS classification

Background

The cancer stem cell (CSC) theory has been proposed to explain tumor heterogeneity and the carcinogenesis of solid tumors. The aim of this study was to clarify the clinical role of CSC-related markers in patients with lung adenocarcinoma and to determine whether each CSC-related marker expression correlates with the histologic subtyping proposed by the International Association for the Study of Lung Cancer (IASLC), the American Thoracic Society (ATS), and the European Respiratory Society (ERS) classifications.

Methods

We reviewed data for all 103 patients in whom complete resection of adenocarcinoma had been performed. Expression of CSC-related markers, ie, aldehyde dehydrogenase 1A1 (ALDH1A1), aldo-keto reductase 1C family member 1 (AK1C1), and 1C family member 3 (AK1C3), was examined using immunostaining on whole-mount tissue slides, and the tumors were reclassified according to the IASLC/ATS/ERS classification.

Results

ALDH1A1 expression was observed in 66.0% of tumors, AK1C1 in 62.7%, and AK1C3 in 86.1%. Immunoreactivities with the frequency of mean expression of ALDH1A1 in papillary predominant adenocarcinoma were significantly higher than those of solid predominant adenocarcinoma (P<0.05). Papillary predominant adenocarcinoma had significantly lower expression of AK1C1 when compared with noninvasive or solid predominant adenocarcinomas (P<0.05). On multivariate analysis, larger tumor size (hazards ratio 1.899, P=0.044), lymph node metastasis (hazards ratio 2.702, P=0.005), and low expression of ALDH1A1 (hazards ratio 3.218, P<0.001) were shown to be independently associated with an unfavorable prognosis.

Conclusion

Immunohistochemistry of ALDH1A1 expression is strongly associated with prognosis. Expression of each CSC-related marker varies according to subtype, suggesting that a comprehensive histologic subtyping approach in the IASLC/ATS/ERS classification provides new molecular biology insights into the genesis of lung adenocarcinoma according to CSC theory.

Prognostic factors and the significance of treatment after recurrence in completely resected stage I non-small cell lung cancer

OBJECTIVE

The objective of this study was to identify the clinicopathologic factors influencing postrecurrence survival (PRS) in and the effect of postrecurrence therapy (PRT) on patients with completely resected stage I non-small cell lung cancer (NSCLC).

METHODS

We reviewed the data of 919 patients in whom complete resection of stage I NSCLC had been performed.

RESULTS

Of the 919 patients, 170 (18.5%) had recurrent disease. Initial PRT was performed in 118 patients (69.1%) (surgery in eight, chemotherapy in 79, radiotherapy in 10, and chemoradiotherapy in 21). On multivariate analyses, PRT (hazard ratio [HR], 0.542; 95% CI, 0.344-0.853; P = .008), female sex (HR, 0.487; 95% CI, 0.297-0.801; P = .005), and differentiation (HR, 1.810; 95% CI, 1.194-2.743; P = .005) demonstrated a statistically significant association with favorable PRS. Bone metastasis (HR, 3.288; 95% CI, 1.783-6.062; P &lt; .001), liver metastasis (HR, 4.518; 95% CI, 1.793-11.379; P = .001), chemotherapy (HR, 0.478; 95% CI, 0.236-0.975; P = .040), epidermal growth factor receptor-tyrosine kinase inhibitors treatment (EGFR-TKIs) (HR, 0.460; 95% CI, 0.245-0.862; P = .015), and nonadenocarcinoma (HR, 2.136; 95% CI, 1.273-3.585; P = .004) were independently and significantly associated with PRS in the 118 patients who underwent any PRT. Subgroup analysis with a combination of these five PRS factors in the patients who underwent any PRT revealed median PRS times of 42.4 months for 20 patients lacking all five risk factors and 18.8 months for 98 patients with at least one of these risk factors (P = .001).

CONCLUSIONS

PRT, sex, and differentiation were independently associated with PRS. In the patients who underwent any PRT, PRS was related to EGFR-TKIs, chemotherapy, histology, and initial recurrence sites. One challenge for the future will be to create systematic treatment strategies for recurrent NSCLC according to the risk factor status of individual patients.

A case of paravertebral mediastinal chordoma without bone destruction

We report a unique case of mediastinal paravertebral chordoma without bone destruction in a 47-year-old Japanese woman. She was admitted to hospital after a tumor was incidentally detected on a chest radiograph. The tumor was located in the paravertebral region of the mediastinum and did not show any destruction of the thoracic vertebra radiologically. The tumor was clinically diagnosed as a benign neurogenic tumor and the tumor was easily removed surgically. Microscopically, the tumor mainly consisted of tumor cells with extensively vacuolated cytoplasm, arranged in cord- and nest-like fashion against a myxoid matrix background. Immunohistochemically, the tumor cells showed diffuse positivity for pancytokeratin (AE1/AE3) and vimentin. The tumor cell nuclei were positive for brachyury, which is a key transcription factor of notochordal development. These results confirmed the tumor to be an extraosseous chordoma in the paravertebral mediastinal region, which is an extremely rare location for a chordoma.

Spin polarization of gapped Dirac surface states near the topological phase transition in TlBi(S(1-x)Se(x))2

We performed systematic spin- and angle-resolved photoemission spectroscopy of TlBi(S(1-x)Se(x))(2) which undergoes a topological phase transition at x ~ 0.5. In TlBiSe(2) (x = 1.0), we revealed a helical spin texture of Dirac-cone surface states with an intrinsic in-plane spin polarization of ~0.8. The spin polarization still survives in the gapped surface states at x > 0.5, although it gradually weakens upon approaching x = 0.5 and vanishes in the nontopological phase. No evidence for the out-of-plane spin polarization was found, irrespective of x and momentum. The present results unambiguously indicate the topological origin of the gapped Dirac surface states, and also impose a constraint on models to explain the origin of mass acquisition of Dirac fermions.

Epidermal growth factor receptor tyrosine kinase defines critical prognostic genes of stage I lung adenocarcinoma

PURPOSE

To identify stage I lung adenocarcinoma patients with a poor prognosis who will benefit from adjuvant therapy.

PATIENTS AND METHODS

Whole gene expression profiles were obtained at 19 time points over a 48-hour time course from human primary lung epithelial cells that were stimulated with epidermal growth factor (EGF) in the presence or absence of a clinically used EGF receptor tyrosine kinase (RTK)-specific inhibitor, gefitinib. The data were subjected to a mathematical simulation using the State Space Model (SSM). "Gefitinib-sensitive" genes, the expressional dynamics of which were altered by addition of gefitinib, were identified. A risk scoring model was constructed to classify high- or low-risk patients based on expression signatures of 139 gefitinib-sensitive genes in lung cancer using a training data set of 253 lung adenocarcinomas of North American cohort. The predictive ability of the risk scoring model was examined in independent cohorts of surgical specimens of lung cancer.

RESULTS

The risk scoring model enabled the identification of high-risk stage IA and IB cases in another North American cohort for overall survival (OS) with a hazard ratio (HR) of 7.16 (P = 0.029) and 3.26 (P = 0.0072), respectively. It also enabled the identification of high-risk stage I cases without bronchioalveolar carcinoma (BAC) histology in a Japanese cohort for OS and recurrence-free survival (RFS) with HRs of 8.79 (P = 0.001) and 3.72 (P = 0.0049), respectively.

CONCLUSION

The set of 139 gefitinib-sensitive genes includes many genes known to be involved in biological aspects of cancer phenotypes, but not known to be involved in EGF signaling. The present result strongly re-emphasizes that EGF signaling status in cancer cells underlies an aggressive phenotype of cancer cells, which is useful for the selection of early-stage lung adenocarcinoma patients with a poor prognosis.

TRIAL REGISTRATION

The Gene Expression Omnibus (GEO) GSE31210.

Local structural studies of the cubic Cd1-xCaxO system through Cd K-edge extended X-ray absorption spectroscopic studies

Cd K-edge extended X-ray absorption fine-structure spectroscopic studies were carried out on Cd(1-x)Ca(x)O (0 ≤ x ≤0.9) solid solutions and the first and second nearest neighbour (NN) distances and their mean square relative displacement σ(2) were estimated. The first NN distance, d(Cd-O)(x), was found to be smaller than its expected value, a(x)/2, obtained from the X-ray diffraction measurements. It increases monotonically and non-linearly with a negative curvature, comparable with that of the a(x) value variation. The variation σ(2) of the 1NN with x is consistent with a disordered solid solution model. The 2NN distances d(Cd-Cd)(x) and d(Cd-Ca)(x) are found to follow the average values obtained by X-ray diffraction with d(Cd-Ca)(x) > d(Cd-Cd)(x). From detailed analysis it is argued that the solid solution exhibits a bimodal distribution of the 1NN distances, d(Cd-O)(x) and d(Ca-O)(x), and that the system belongs to a persistent type.

Expression of hepatocyte growth factor in the skin of amyotrophic lateral sclerosis

OBJECTIVES

Hepatocyte growth factor (HGF) is one of the most potent survival-promoting factors for motor neurons. Overexpression of neuronal HGF has been shown to result in the attenuation of neuronal cell death and progression of disease in a familial amyotrophic lateral sclerosis (ALS) transgenic mouse model. HGF might be beneficial for motor neuron survival and is a good candidate agent for the treatment of ALS. So far, studies of the skin of ALS have shown unique pathological and biochemical abnormalities. However, there has been no study of HGF in ALS skin.

MATERIALS AND METHODS

We made a quantitative immunohistochemical study of the expression of HGF in the skin from 19 patients with sporadic ALS and 16 controls.

RESULTS

Hepatocyte growth factor immunoreactivity was positive in the epidermis, some dermal blood vessels, and glands in patients with ALS. These findings became more conspicuous as ALS progressed. The optical density for HGF immunoreactivity of the nucleus and the cytoplasm in the epidermis in ALS was significantly higher (P < 0.001 and P < 0.001) than in controls. There was a significant positive relation (r = 0.53, P < 0.02 and r = 0.73, P < 0.001) between HGF immunoreactivity and duration of illness in the nucleus and the cytoplasm in the epidermis in patients with ALS.

CONCLUSIONS

These findings suggest that changes in HGF in ALS skin are related to the disease process and that metabolic alterations of HGF may take place in the skin of patients with ALS.

Abstract LB-99: EGF receptor tyrosine kinase defines critical prognostic genes of stage IA lung adenocarcinoma

Non-small cell lung cancer (NSCLC) is the commonest and the most fatal histological subtype of lung cancer. About 10-30% of patients diagnosed as stage IA (the earliest stage of a lung tumor, smaller than three centimeters in diameter with no evidence of regional lymph node and/or regional metastasis) and submitted to surgery die due to recurrence. Therefore, the identification of prognostic biomarkers for stage IA lung adenocarcinoma with poor prognosis is of great importance to select patients who will be benefited by adjuvant therapy. To the best of our knowledge, there is not a set of genes that identifies these patients. It is known that epidermal growth factor (EGF) signaling pathway is closely related to aggressive phenotypes of lung and other cancers. EGFR tyrosine kinase-specific inhibitor, namely gefitinib is expected to alter the gene expression patterns caused by EGFR tyrosine kinase activity. We performed microarray assays in order to obtain the entire gene expression time course profile of human primary lung epithelial cells that were stimulated with EGF in both the presence and absence of gefitinib. The time courses are composed of 19 time points along 48 hours. The data were subjected to a mathematical analysis, namely the State Space Model (SSM) in order to select genes with gene expressions altered by gefitinib. One hundred thirty nine genes were identified. These genes were used as expression signatures to train a risk scoring model that classifies patients in high- or low-risk (risk of dying in five years). This model was trained by using a data set composed of 253 North American patients with lung adenocarcinomas. Then, the predictive ability of the risk scoring model was examined in two independent cohorts composed of North American and Japanese patients. The model enabled the statistically significant identification of high-risk stage IA lung adenocarcinoma in both cohorts, with hazard ratios (HRs) for death of 7.16 (P=0.029) for North American and 10.98 (P=0.008) for Japanese. The set of 139 genes altered by gefitinib includes several ones that are involved in biological aspects of cancer phenotypes but are yet unknown to be involved in EGF signaling. This result strongly re-emphasizes that EGF signaling status underlies aggressive phenotype of cancer cells, and also suggests the first set of genes that are useful for the identification of stage IA lung adenocarcinoma patients with poor prognosis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr LB-99. doi:1538-7445.AM2012-LB-99

Abstract 2904: EGFR-targeted gold liposome for molecular imaging and therapy on NSCLC cells

Nanotechnologies are in development for monitoring drug delivery and therapeutic effect for cancer. However, tumor-targeted multifunctional nanoparticles for imaging of and therapy of lung cancer are not available. The Epidermal growth factor receptor (EGFR) is overexpressed in approximately 80% of non-small cell lung cancer (NSCLC) and is a target for novel therapeutics, however, the clinical results using EGFR inhibitors for NSCLC treatment had mixed results. These results indicate that EGFR expression or its mutational status is solely not a reliable marker to determine the outcome. Therefore, we have developed liposome (120nm) encapsulated with colloidal gold that are conjugated to therapeutic anti-EGFR antibodies (Katayama Chemical Industries Co. Ltd. Osaka, Japan) to determine the molecular specific imaging of NSCLC. The colloidal gold is used for optical imaging and the anti-EGFR antibody for therapy. In the present study, we investigated in vitro effect of these liposomes on EGFR-expressing (HCC827 and H1299) and EGFR-null (H520) NSCLC cells. EGFR-targeted liposome exhibited a strong antitumor effect on EGFR-expressing NSCLC cells. On the other hands, no significant growth inhibitory effects were observed on non-targeted liposome-treated cells. Intriguingly, treatment with EGFR-targeted liposome resulted in significantly higher cell death as compared with anti-EGFR antibody and liposome alone. Furthermore, reflected polarizing microscopy showed that the concentration of EGFR-targeted liposome bound to EGFR-expressing NSCLC cells increased, but EGFR-null cells did not. When EGFR was inhibited pharmacologically, the binding efficiency of EGFR-targeted liposome was attenuated on EGFR-expressing NSCLC cells. These findings indicate that EGFR-targeted liposome are selectively bound and delivered to EGFR expressing NSCLC cells but not the EGFR-null NSCLC cells. We are currently determining in vivo effect of EGFR-targeted liposome using subcutaneous HCC827 and H520 tumor models. Our findings demonstrated that EGFR-targeted liposome is a promising agent for therapy and molecular imaging of NSCLC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2904. doi:1538-7445.AM2012-2904

Topological surface states in lead-based ternary telluride Pb(Bi(1-x)Sb(x))2Te4

We have performed angle-resolved photoemission spectroscopy on Pb(Bi(1-x)Sb(x))2Te4, which is a member of lead-based ternary tellurides and has been theoretically proposed as a candidate for a new class of three-dimensional topological insulators. In PbBi2Te4, we found a topological surface state with a hexagonally deformed Dirac-cone band dispersion, indicating that this material is a strong topological insulator with a single topological surface state at the Brillouin-zone center. Partial replacement of Bi with Sb causes a marked change in the Dirac carrier concentration, leading to the sign change of Dirac carriers from n type to p type. The Pb(Bi(1-x)Sb(x))2Te4 system with tunable Dirac carriers thus provides a new platform for investigating exotic topological phenomena.