RESUMO
The combination of lenalidomide (Revlimid® , R) and dexamethasone (d) is a standard regimen for patients with relapsed/refractory multiple myeloma (rrMM). With this regimen, only a small fraction of patients will achieve high quality responses [≥ very good partial response (VGPR)]. The combination of bendamustine (B), lenalidomide and dexamethasone (BRd) has shown high efficacy in patients with advanced rrMM. However, dose-limiting haematotoxicity restricted its use in extensively pre-treated patient populations. This prospective, multicentre Phase II study evaluated the efficacy and safety of BRd in rrMM patients with one prior line of therapy. Fifty patients were enrolled (median age 68·5 years [range 46-83]) and were treated with B 75 mg/m2 days 1, 2; R 25 mg days 1-21 and d (40/20 mg) days 1, 8, 15 and 22, for 6 28-day induction cycles, followed by 12 cycles with Rd alone. Pegfilgrastim was administered according to protocol-defined criteria. The study aimed to demonstrate a complete response (CR)/VGPR rate of >40% after induction therapy. Of 45 evaluable patients, 23 (51%) achieved a CR/VGPR. Grade 4 neutropenia or thrombocytopenia occurred in 17 (34%) and 8 (16%) of patients, respectively. BRd is a safe and efficacious regimen as a second line treatment for rrMM, leading to high quality responses in a considerable proportion of patients.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Terapia de Salvação/métodos , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cloridrato de Bendamustina/efeitos adversos , Dexametasona/administração & dosagem , Humanos , Lenalidomida , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Neutropenia/induzido quimicamente , Indução de Remissão/métodos , Talidomida/administração & dosagem , Talidomida/análogos & derivados , Trombocitopenia/induzido quimicamente , Trombocitopenia/complicações , Resultado do TratamentoRESUMO
BACKGROUND: While health data sharing for research purposes is strongly supported in principle, it can be challenging to implement in practice. Little is known about the actual bottlenecks to health data sharing in Switzerland. AIMS OF THE STUDY: This study aimed to assess the obstacles to Swiss health data sharing, including legal, ethical and logistical bottlenecks. METHODS: We identified 37 key stakeholders in data sharing via the Swiss Personalised Health Network ecosystem, defined as being an expert on sharing sensitive health data for research purposes at a Swiss university hospital (or a Swiss disease cohort) or being a stakeholder in data sharing at a public or private institution that uses such data. We conducted semi-structured interviews, which were transcribed, translated when necessary, and de-identified. The entire research team discussed the transcripts and notes taken during each interview before an inductive coding process occurred. RESULTS: Eleven semi-structured interviews were conducted (primarily in English) with 17 individuals representing lawyers, data protection officers, ethics committee members, scientists, project managers, bioinformaticians, clinical trials unit members, and biobank stakeholders. Most respondents felt that it was not the actual data transfer that was the bottleneck but rather the processes and systems around it, which were considered time-intensive and confusing. The templates developed by the Swiss Personalised Health Network and the Swiss General Consent process were generally felt to have streamlined processes significantly. However, these logistics and data quality issues remain practical bottlenecks in Swiss health data sharing. Areas of legal uncertainty include privacy laws when sharing data internationally, questions of "who owns the data", inconsistencies created because the Swiss general consent is perceived as being implemented differently across different institutions, and definitions and operationalisation of anonymisation and pseudo-anonymisation. Many participants desired to create a "culture of data sharing" and to recognise that data sharing is a process with many steps, not an event, that requires sustainability efforts and personnel. Some participants also stressed a desire to move away from data sharing and the current privacy focus towards processes that facilitate data access. CONCLUSIONS: Facilitating a data access culture in Switzerland may require legal clarifications, further education about the process and resources to support data sharing, and further investment in sustainable infrastructureby funders and institutions.
Assuntos
Privacidade , Humanos , Disseminação de Informação , Pesquisa Qualitativa , SuíçaRESUMO
BACKGROUND & AIMS: Human colorectal carcinomas display an infiltrative front of invasion where tumor cells undergo an epithelomesenchymal transition associated with low survival. Epithelomesenchymal transition is regulated by a nuclear beta-catenin accumulation, and subsequently, activation of beta-catenin/TCF4 target genes similar to CYCLIN D(1). Unexpectedly, these tumor cells are characterized by low proliferation, which correlates with the expression of the cell cycle inhibitor p16(INK4A). Therefore, we investigated the molecular mechanism of the transcriptional regulation of p16(INK4A) in colorectal cancer and its correlation with survival. METHODS: Molecular biological techniques were used for investigating the transcriptional mechanisms of the p16(INK4A) gene regulation. Moreover, p16(INK4A) expression was correlated with the 10-year survival of patients with colorectal carcinomas. RESULTS: In colorectal carcinomas, expression of the p16(INK4A) gene is regulated by beta-catenin/TCF4 and correlates with low survival rates of patients with tumors displaying an infiltrative front of invasion. CONCLUSIONS: beta-catenin/TCF4 regulates cell cycle promoting (c-MYC, CYCLIN D(1)) and inhibiting genes (p16(INK4A)) at the same time in the mesenchymally differentiated tumor cells at the front of invasion. The function of p16(INK4A) seems to supersede in this context thus leading to low proliferation. Moreover, these tumor cells seem to govern the outcome of colorectal cancer independently of their proliferation.
Assuntos
Neoplasias Colorretais/mortalidade , Genes p16 , beta Catenina/fisiologia , Adulto , Idoso , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Regiões Promotoras Genéticas , Fator de Transcrição 4 , Fatores de Transcrição/metabolismoRESUMO
Tenascin-C (TN-C) is a component of the extracellular matrix (ECM). It is expressed during development and re-expressed in many types of cancers, where it is involved in the modulation of adhesion and proliferation. TN-C expression is especially high at sites of epithelial mesenchymal transition (EMT), which are found frequently at the invasion front of well-differentiated human colorectal adenocarcinomas. Tumor cells in this compartment are characterized by a strong nuclear expression of the oncogenic transcription factor beta-catenin. Here, we demonstrate that TN-C is a beta-catenin target gene in human colorectal tumors. Thus, by far the most common mutations in colorectal tumors, found in the Wnt-signaling pathway and leading to the stabilizing of beta-catenin, might influence invasion by altering adhesive properties and EMT of tumor cells.
Assuntos
Regulação Neoplásica da Expressão Gênica , Tenascina/genética , beta Catenina/metabolismo , Adenocarcinoma , Diferenciação Celular , Linhagem Celular Tumoral , Núcleo Celular/fisiologia , Neoplasias Colorretais , Células Epiteliais/patologia , Humanos , Mesoderma/patologia , Invasividade Neoplásica , beta Catenina/genéticaRESUMO
Expression of the urokinase plasminogen activator (uPA) increases during the progression of colorectal tumors from adenomas to carcinomas. The highest amounts of uPA are found at the invasion front of carcinomas, which also displays a strong expression of nuclear beta-catenin and is therefore a region expressing beta-catenin target genes at high levels. Here we show that beta-catenin contributes to the transactivation of uPA. Therefore, beta-catenin might have an impact on the capacity of colorectal tumors for invasion and metastasis, as well as dormancy, which are hallmarks of cancer.
Assuntos
Neoplasias Colorretais/enzimologia , Proteínas do Citoesqueleto/fisiologia , Regulação Enzimológica da Expressão Gênica , Transativadores/fisiologia , Ativador de Plasminogênio Tipo Uroquinase/genética , Linhagem Celular Tumoral , Elementos Facilitadores Genéticos , Humanos , Regiões Promotoras Genéticas , Regulação para Cima , beta CateninaRESUMO
Colorectal carcinomas with microsatellite instability accumulate errors in short repetitive DNA repeats, especially mono and dinucleotide repeats. One such error-prone A(9) monorepeat is found in exon 17 of the TCF-4 gene. TCF-4 and beta-catenin form a transcription complex, which is important for both maintenance of normal epithelium and development of colorectal tumors. To elucidate the relevance of frameshift mutations in the TCF-4 in colorectal carcinogenesis, a variety of investigations in human tumors and cell lines was performed. It was found that mutations in the TCF-4 A(9) repeat do not contribute to tumorigenesis and seem to be passenger mutations.
Assuntos
Neoplasias Colorretais/genética , Mutação da Fase de Leitura , Repetições de Microssatélites/genética , Transativadores , Fatores de Transcrição/genética , Neoplasias Colorretais/patologia , Proteínas do Citoesqueleto/genética , Éxons , Humanos , Mutagênese , Fatores de Transcrição TCF , Proteína 2 Semelhante ao Fator 7 de Transcrição , Ativação Transcricional , Transfecção , beta CateninaRESUMO
The majority of colorectal cancers (CRCs) are characterized by a dysregulated canonical Wnt-signaling pathway leading to the stabilization and subsequent cellular increase and accumulation of ß-catenin. After translocation into the nucleus, it acts as a transcription factor resulting in the expression of ß-catenin target genes. These resemble most of the hallmarks of cancer except eternal life. The central mediator of this hallmark is hTERT (human telomerase reverse transcriptase). The hTERT gene is regulated, besides others, by the transcription factor c-Myc and, thus, indirectly via ß-catenin as c-Myc is a ß-catenin target gene. Interestingly, the expression patterns of hTERT and ß-catenin, but not c-Myc are overlapping, probably because c-Myc is not only regulated by ß-catenin, but also by many other transcription factors and pathways. Therefore, we argued that hTERT might be a direct target gene of ß-catenin. In this study, we show evidence that ß-catenin directly regulates the expression of the hTERT gene.
Assuntos
Neoplasias Colorretais/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/fisiologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Telomerase/metabolismo , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Imuno-Histoquímica , Oligonucleotídeos/genética , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Telomerase/genética , beta Catenina/uso terapêuticoRESUMO
Invasion by colorectal carcinomas is characterized by an epithelial-mesenchymal transition (EMT)-like dedifferentiation of the tumor cells. However, a redifferentiation towards an epithelial phenotype, resembling a mesenchymal-epithelial transition, is detectable in metastases. This indicates that malignant progression is based on dynamic processes, which cannot be explained solely by irreversible genetic alterations, but must be additionally regulated by the tumor environment. The main oncoprotein in colorectal cancer is the Wnt pathway effector beta-catenin, which is overexpressed due to mutations in the APC tumor suppressor in most cases. EMT of the tumor cells is associated with a nuclear accumulation of the transcriptional activator beta-catenin, which is reversed in metastases. Nuclear beta-catenin is involved in two fundamental processes in embryonic development: EMT and stem cell formation. Accumulating data demonstrate that aberrant nuclear expression of beta-catenin can also confer these two abilities to tumor cells, thereby driving malignant tumor progression.