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1.
Tob Control ; 28(3): 334-345, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30135114

RESUMO

OBJECTIVE: To examine the quality of tobacco industry-funded data on the illicit tobacco trade (ITT) through a systematic review of existing assessments of industry-funded data on ITT. DATA SOURCES: Papers and reports assessing tobacco industry-funded data on ITT were obtained via searches of 8 academic databases, Google searches and correspondence with ITT experts. STUDY SELECTION: Inclusion criteria identified 35 English-language papers containing an original assessment of tobacco industry-funded data. DATA EXTRACTION: Using a coding framework, information was extracted from the assessments regarding the quality of tobacco industry data. Documents were second-coded, achieving 94% intercoder reliability with all disagreements resolved. DATA SYNTHESIS: Of the 35 assessments reviewed, 31 argued that tobacco industry estimates were higher than independent estimates. Criticisms identified problems with data collection (29), analytical methods (22) and presentation of results (21), which resulted in inflated ITT estimates or data on ITT that were presented in a misleading manner. Lack of transparency from data collection right through to presentation of findings was a key issue with insufficient information to allow replication of the findings frequently cited. CONCLUSIONS: Tobacco industry data on ITT are not reliable. At present, the tobacco industry continues to fund and disseminate ITT research through initiatives such as PMI IMPACT. If industry data on ITT cannot meet the standards of accuracy and transparency set by high-quality research publications, a solution may be to tax tobacco companies and administer the resulting funds to experts, independent of the tobacco industry, who use previously developed reliable models for measuring ITT.


Assuntos
Comércio/estatística & dados numéricos , Crime/estatística & dados numéricos , Indústria do Tabaco/economia , Comércio/legislação & jurisprudência , Coleta de Dados/normas , Humanos , Reprodutibilidade dos Testes , Produtos do Tabaco/economia
2.
Int J Cancer ; 124(1): 16-26, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18814281

RESUMO

Activating mutations in the NRAS gene, which occur predominantly in codon 61 (Q61R, Q61K) are among the most common genetic events in malignant melanoma. NRAS protein with oncogenic codon 61 mutations may therefore be good therapeutic targets. In the present study, we used gene expression profiling as a method for global characterization of gene expression alterations that resulted from treatment of melanoma cells with siRNA specifically targeting NRAS(Q61R). Sixteen probe sets representing 15 unique genes were identified whose expression was significantly altered by siRNA against NRAS(Q61R) in 2 melanoma cell lines. The genes with altered expression are involved in several functions, including modulation of cell growth, invasion and migration. The results suggest that downregulation of cyclin E2 and cyclin D1 and also upregulation of the negative cell-cycle regulator HBP1 in NRAS(Q61R) knockdown cells contribute to the inhibition of cell proliferation. Furthermore, suppression of oncogenic NRAS results in reduced migration and invasion, which is accompanied by downregulation of EphA2 (a receptor tyrosine kinase), uPAR (urokinase receptor) and cytoskeleton proteins such as leupaxin, paxillin and vinculin. These studies support the concept that suppression of oncogenic NRAS by siRNA can induce growth arrest and inhibit invasion of human melanoma cells by modulating the levels of these gene products.


Assuntos
Regulação Neoplásica da Expressão Gênica , Genes ras , Melanoma/metabolismo , Mutação , Proteína Oncogênica p21(ras)/metabolismo , Neoplasias Cutâneas/metabolismo , Moléculas de Adesão Celular/farmacologia , Linhagem Celular Tumoral , Ciclina D1/metabolismo , Ciclinas/metabolismo , Citoesqueleto/metabolismo , Humanos , Paxilina/farmacologia , Fenótipo , Fosfoproteínas/farmacologia , Vinculina/farmacologia
3.
BMJ Open ; 9(9): e028506, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31551373

RESUMO

OBJECTIVES: UK standardised packaging legislation was introduced alongside pack size and product descriptor restrictions of the European Union Tobacco Products Directive to end tobacco marketing and misinformation via the pack. This paper aims to assess compliance with the restrictions and identify attempts to continue to market tobacco products and perpetuate misperceptions of harm post legislation. DESIGN, SETTING AND INTERVENTION: A prospective study of the introduction of standardised packaging of tobacco products to the UK. PARTICIPANTS AND OUTCOMES: We analysed commercial sales data to assess whether the legally required changes in pack branding, size and name were implemented. To explore any adaptations to products and packaging we analysed sales data, monthly pack purchases of factory-made (FM) cigarettes and roll-your-own (RYO) tobacco, tobacco advertisements from retail trade magazines and articles on tobacco from commercial literature (retail trade, market analyst and tobacco company publications). RESULTS: One month after full implementation of the UK and European Union policies, 97% FM and 98% RYO was sold in compliant packaging. Nevertheless, tobacco companies made adaptations to tobacco products which enabled continued brand differentiation after the legislation came into force. For example, flavour names previously associated with low tar were systematically changed to colour names arguably facilitating continued misperceptions about the relative harms of products. Tobacco companies used the 1-year sell-through to their advantage by communicating brand name changes and providing financial incentives for retailers to buy large volumes of branded packs. In addition, tobacco companies continued to market their products to retailers and customers by innovating exemptions to the legislation, namely, filters, packaging edges, seals, multipack outers, RYO accessories, cigars and pipe tobacco. CONCLUSIONS: Tobacco companies adapted to packaging restrictions by innovating their tobacco products and marketing activities. These findings should enable policy makers globally to close loopholes and increase the potential efficacy of standardised packaging policies.


Assuntos
Comércio/legislação & jurisprudência , Marketing/métodos , Embalagem de Produtos/legislação & jurisprudência , Embalagem de Produtos/normas , Produtos do Tabaco/legislação & jurisprudência , Estudos Longitudinais , Marketing/normas , Estudos Prospectivos , Indústria do Tabaco/legislação & jurisprudência , Indústria do Tabaco/estatística & dados numéricos , Produtos do Tabaco/normas , Reino Unido
4.
PLoS One ; 14(2): e0211758, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30807582

RESUMO

BACKGROUND: Standardised tobacco packaging has been, and remains, a contentious policy globally, attracting corporate, public health, political, media and popular attention. In January 2015, the UK Government announced it would vote on draft regulations for the policy before the May 2015 General Election. We explored reactions to the announcement on Twitter, in comparison with an earlier period of little UK Government activity on standardised packaging. METHODS: We obtained a random sample of 1038 tweets in two 4-week periods, before and after the UK Government's announcement. Content analysis was used to examine the following Tweet characteristics: support for the policy, purpose, Twitter-user's geographical location and affiliation, and evidence citation and quality. Chi-squared analyses were used to compare Tweet characteristics between the two periods. RESULTS: Overall, significantly more sampled Tweets were in favour of the policy (49%) in comparison to those opposed (19%). Yet, at Time 2, following the announcement, a greater proportion of sampled tweets opposed standardised packaging compared to the period sampled at Time 1, prior to the announcement (p<0.001). The quality of evidence and research cited in URLs linked at Time 2 was significantly lower than at Time 1 (p<0.001), with peer-reviewed research more likely to be shared in positive Tweets (p<0.001) and in Tweets linking to URLs originating from the health sector (p<0.001). The decline in the proportion of positive Tweets was mirrored by a reduction in Tweets by health sector Twitter-users at Time 2 (p<0.001). CONCLUSIONS: Microblogging sites can reflect offline policy debates and are used differently by policy proponents and opponents dependent on the policy context. Twitter-users opposed to standardised packaging increased their activity following the Government's announcement, while those in support broadly maintained their rate of Twitter engagement. The findings offer insight into the public health community's options for using Twitter to influence policy and disseminate research. In particular, proliferation of Twitter activity following pro-public health policy announcements could be considered to ensure pro-health messages are not overshadowed by anti-regulation voices.


Assuntos
Governo , Política de Saúde/legislação & jurisprudência , Saúde Pública/legislação & jurisprudência , Humanos , Mídias Sociais , Reino Unido
5.
Mol Cancer Ther ; 14(2): 620-30, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25527633

RESUMO

Insulin-like growth factor receptor 1 (IGF-1R)-targeting therapies are currently at an important crossroad given the low clinical response rates seen in unselected patients. Predictive biomarkers for patient selection are critical for improving clinical benefit. Coupling in vitro sensitivity testing of BMS-754807, a dual IGF-1R/IR inhibitor, with genomic interrogations in 60 human colorectal cancer cell lines, we identified biomarkers correlated with response to BMS-754807. The results showed that cell lines with BRAF(V600E) or KRAS(G13D) mutation were resistant, whereas cell lines with wild-type of both KRAS and BRAF were particularly sensitive to BMS-754807 if they have either higher RNA expression levels of IR-A or lower levels of IGFBP6. In addition, the cell lines with KRAS mutations, those with either insulin receptor substrate 2 (IRS2) copy number gain (CNG) or higher IGF-1R expression levels, were more sensitive to the drug. Furthermore, cell lines with IRS2 CNG had higher levels of ligand-stimulated activation of IGF-1R and AKT, suggesting that these cell lines with IGF-IR signaling pathways more actively coupled to AKT signaling are more responsive to IGF-1R/IR inhibition. IRS2 siRNA knockdown reduced IRS2 protein expression levels and decreased sensitivity to BMS-754807, providing evidence for the functional involvement of IRS2 in mediating the drug response. The prevalence of IRS2 CNG in colorectal cancer tumors as measured by qPCR-CNV is approximately 35%. In summary, we identified IRS2 CNG, IGF-1R, IR-A, and IGFBP6 RNA expression levels, and KRAS and BRAF mutational status as candidate predictive biomarkers for response to BMS-754807. This work proposed clinical development opportunities for BMS-754807 in colorectal cancer with patient selection to improve clinical benefit.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/genética , Dosagem de Genes , Proteínas Substratos do Receptor de Insulina/genética , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas/genética , Pirazóis/farmacologia , Triazinas/farmacologia , Proteínas ras/genética , Western Blotting , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA/genética , Análise Mutacional de DNA , Amplificação de Genes/efeitos dos fármacos , Humanos , Proteína 6 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Ligantes , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras) , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor de Insulina/antagonistas & inibidores
6.
BMJ Open ; 4(2): e003757, 2014 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-24523419

RESUMO

OBJECTIVES: To examine the volume, relevance and quality of transnational tobacco corporations' (TTCs) evidence that standardised packaging of tobacco products 'won't work', following the UK government's decision to 'wait and see' until further evidence is available. DESIGN: Content analysis. SETTING: We analysed the evidence cited in submissions by the UK's four largest TTCs to the UK Department of Health consultation on standardised packaging in 2012. OUTCOME MEASURES: The volume, relevance (subject matter) and quality (as measured by independence from industry and peer-review) of evidence cited by TTCs was compared with evidence from a systematic review of standardised packaging . Fisher's exact test was used to assess differences in the quality of TTC and systematic review evidence. 100% of the data were second-coded to validate the findings: 94.7% intercoder reliability; all differences were resolved. RESULTS: 77/143 pieces of TTC-cited evidence were used to promote their claim that standardised packaging 'won't work'. Of these, just 17/77 addressed standardised packaging: 14 were industry connected and none were published in peer-reviewed journals. Comparison of TTC and systematic review evidence on standardised packaging showed that the industry evidence was of significantly lower quality in terms of tobacco industry connections and peer-review (p<0.0001). The most relevant TTC evidence (on standardised packaging or packaging generally, n=26) was of significantly lower quality (p<0.0001) than the least relevant (on other topics, n=51). Across the dataset, TTC-connected evidence was significantly less likely to be published in a peer-reviewed journal (p=0.0045). CONCLUSIONS: With few exceptions, evidence cited by TTCs to promote their claim that standardised packaging 'won't work' lacks either policy relevance or key indicators of quality. Policymakers could use these three criteria-subject matter, independence and peer-review status-to critically assess evidence submitted to them by corporate interests via Better Regulation processes.


Assuntos
Embalagem de Produtos/normas , Indústria do Tabaco , Produtos do Tabaco , Comércio , Humanos , Reino Unido
7.
Cancer Res ; 71(24): 7597-607, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22042792

RESUMO

Insulin-like growth factor (IGF) signaling has been implicated in the resistance to hormonal therapy in breast cancer. Using a model of postmenopausal, estrogen-dependent breast cancer, we investigated the antitumor effects of the dual IGF-1R/InsR tyrosine kinase inhibitor BMS-754807 alone and in combination with letrozole or tamoxifen. BMS-754807 exhibited antiproliferative effects in vitro that synergized strongly in combination with letrozole or 4-hydroxytamoxifen and fulvestrant. Similarly, combined treatment of BMS-754807 with either tamoxifen or letrozole in vivo elicited tumor regressions not achieved by single-agent therapy. Notably, hormonal therapy enhanced the inhibition of IGF-1R/InsR without major side effects in animals. Microarray expression analysis revealed downregulation of cell-cycle control and survival pathways and upregulation of erbB in response to BMS-754807 plus hormonal therapy, particularly tamoxifen. Overall, these results offer a preclinical proof-of-concept for BMS-754807 as an antitumor agent in combination with hormonal therapies in hormone-sensitive breast cancer. Cooperative cell-cycle arrest, decreased proliferation, and enhanced promotion of apoptosis may contribute to antitumor effects to be gauged in future clinical investigations justified by our findings.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias Mamárias Experimentais/tratamento farmacológico , Pirazóis/farmacologia , Triazinas/farmacologia , Animais , Antineoplásicos Hormonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Estradiol/farmacologia , Estrogênios/metabolismo , Feminino , Fulvestranto , Perfilação da Expressão Gênica , Humanos , Letrozol , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nitrilas/administração & dosagem , Nitrilas/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/antagonistas & inibidores , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Tamoxifeno/administração & dosagem , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologia , Triazóis/administração & dosagem , Triazóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Cancer Res ; 70(18): 7221-31, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20807811

RESUMO

Agents targeting insulin-like growth factor-I receptor (IGF-IR), including antibodies and small-molecule inhibitors, are currently in clinical development for the treatment of cancers including sarcoma. However, development of resistance is a common phenomenon resulting in failures of anticancer therapies. In light of this problem, we developed two resistant models from the rhabdomyosarcoma cell line Rh41: Rh41-807R, with acquired resistance to BMS-754807, a small-molecule dual-kinase inhibitor targeting IGF-IR and insulin receptor (IR), and Rh41-MAB391R, with resistance to MAB391, an IGF-IR-blocking antibody. In addition, tumor xenograft models were established from Rh41 and Rh41-807R cell lines. Gene expression and DNA copy number analyses of these models revealed shared as well as unique acquired resistance mechanisms for the two types of IGF-IR inhibitors. Each resistant model used different signaling pathways as a mechanism for proliferation. Platelet-derived growth factor receptor α (PDGFRα) was amplified, overexpressed, and constitutively activated in Rh41-807R cells and tumors. Knockdown of PDGFRα by small interfering RNA in Rh41-807R resensitized the cells to BMS-754807. Synergistic activities were observed when BMS-754807 was combined with PDGFRα inhibitors in the Rh41-807R model in vitro. In contrast, AXL expression was highly elevated in Rh41-MAB391R but downregulated in Rh41-807R. Notably, BMS-754807 was active in Rh41-MAB391R cells and able to overcome resistance to MAB391, but MAB391 was not active in Rh41-807R cells, suggesting potentially broader clinical activity of BMS-754807. This is the first study to define and compare acquired resistance mechanisms for IGF-IR-targeted therapies. It provides insights into the differential acquired resistance mechanisms for IGF-IR/IR small-molecule inhibitor versus anti-IGF-IR antibody.


Assuntos
Anticorpos Monoclonais/farmacologia , Pirazóis/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Rabdomiossarcoma/terapia , Triazinas/farmacologia , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Receptor IGF Tipo 1/biossíntese , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/imunologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/agonistas , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/biossíntese , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/deficiência , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/genética , Rabdomiossarcoma/imunologia , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Endocrinology ; 151(9): 4123-32, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20610571

RESUMO

The biology of IGF-IR/IR signaling was studied in normal mouse embryonic fibroblasts (MEFs) that were either wild type (wt), heterozygous (het), or null for the IGF-IR. The ability of IGF-I, IGF-II, or insulin to stimulate serum-starved MEFs was characterized by gene expression profiling and biochemical analyses for activation of downstream signals. Each genotypic group of MEFs exhibited distinct patterns of expression both while resting and in response to stimulation. The insulin receptor (IR) pathway in IGF-IR null MEFs was hypersensitive to insulin ligand stimulation resulting in greater AKT phosphorylation than in wt or het MEFs stimulated with the same ligand. Interestingly, the IR pathway hypersensitivity in IGF-IR null MEFs occurred with no observed changes in the levels of IR isoforms A or B. A new small molecule IGF-IR inhibitor (BMS-754807), having equipotent activity against both IGF-IR and IR, proved effective in suppressing both AKT and ERK phosphorylation from both the IGF-IR and IR pathways by all three ligands tested in wt, het, and null MEFs. The use of a dual IGF-IR/IR inhibitor addresses concerns about the use of growth inhibiting therapies directed against the IGF-IR receptor in certain cancers. Lastly, comparison of the antiproliferative effects (IC(50)s) of various compounds in wt vs. null MEFs demonstrates that genetically characterized MEFs provide a simple and inexpensive tool with which to define compounds as having mostly on-target or off-target IGF-IR activities because off-target compounds affect both wt and null MEFs equally.


Assuntos
Proliferação de Células/efeitos dos fármacos , Pirazóis/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor de Insulina/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Triazinas/farmacologia , Animais , Western Blotting , Células Cultivadas , Análise por Conglomerados , Embrião de Mamíferos/citologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Insulina/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like II/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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