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Research advances on effective methods to prevent, diagnose, and treat cancer continue to emerge through clinical and genomic research. Most clinical trial and genomic research participants identify as White which limits the generalizability of research findings to non-White populations. With the development and access to technology, digital delivery of salient and tailored health education may provide innovative pathways to increase representation of African Americans (AA) and Hispanics in research. This project focused on the creation of a bioethical sensitive education video aimed at increasing participation in clinical trials and genomic research by bringing together experts from the community, healthcare, biomedical research, and public health. The goal was to utilize existing educational resources to create a tailored message to address AA/Hispanics' beliefs, values, and bioethical concerns related to participation in clinical and genomic research. Models of behavior change and communication theories were leveraged to frame key components of the message, which then informed the framework for the animated video. Development of the video consisted of six iterative phases: 1) writing sessions; 2) storyboarding; 3) animating; 4) screening/revisions; 5) acceptability testing; 6) finalization. The final animated video is approximately 5 min in length and covers several topics including the goal of clinical research, disparities in research participation, bioethical concerns, and genomic research regulations. Increasing AA and Hispanic participation in clinical and genomic research is imperative to achieving health equity. Tailored messages via short videos may assist in addressing the barriers and facilitators towards research participation and increase intentions to enroll in trials.
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Negro ou Afro-Americano , Hispânico ou Latino , Humanos , Negro ou Afro-Americano/psicologia , Feminino , Genômica/ética , Masculino , Pesquisa Biomédica/ética , Participação do Paciente , Ensaios Clínicos como Assunto , Gravação em Vídeo , Pesquisa em Genética/éticaRESUMO
INTRODUCTION: The formative period of the specialty of gynecologic oncology was from 1968 to 1972 and became a board-certified specialty in 1973. During this formation there were no Black physicians participating in this process. We chronicle and document the incorporation of the first three board-certified Black physicians in the specialty of gynecologic oncology here for historical purposes. METHODS: We highlight the hostile climate experienced by Black physicians before and during the formation of gynecologic oncology, review the acceptance and training of the first three Black physicians in the specialty and recognize their significant contributions to the field. RESULTS: The biographies and the narrative of these men describe their impact and contribution to medicine. We chronicle the historic presence of the first board-certified Black gynecologic oncologists and pelvic surgeons in the United States. CONCLUSION: These three men represent the Black Founding Fathers of gynecologic oncology. Their perseverance in the face of adversity and commitment to excellence have left an indelible impact on the institutions that they developed, the individuals that they trained, and the patients that they served.
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Negro ou Afro-Americano , Ginecologia , Oncologia , Humanos , Negro ou Afro-Americano/história , Negro ou Afro-Americano/psicologia , Oncologia/história , Ginecologia/história , História do Século XX , Feminino , Estados Unidos , MasculinoRESUMO
OBJECTIVE: To assess the contemporary incidence of cancers using American Samoa as a learning set for insights into similar populations. METHODS: A retrospective observational analysis of de-identified data held in public-access databases (2004-2014) and data on uterine cancer from a hospital, both in American Samoa (2015-2016). RESULTS: There were 341 new cases of cancer in 2004-2014 (111 per 100 000 women/year), including breast (20.2%), uterine (19.4%), and cervical (5.0%); and 287 in 2011-2015 (103 per 100 000 women/year), including uterine (24.0%), breast (18.5%), and cervical (5.2%). Uterine cancer increased from 21.4 to 60.3 per 100 000 women/year, becoming the most common cancer in American Samoa. In 2011-2015, the incidence-rate ratio of uterine cancer to other cancers in American Samoa was 1.3-, 3.8-, 4.6-, 7.7-, and 23-fold higher than breast, colon, cervical, ovarian, and lung cancer, respectively. Among the most recent cases (n=33), median age was 55 years (10 [30.3%] <50 years), median BMI was 38.2; and 11 (33.3%) cases had grade 3 histology. CONCLUSION: The pattern of cancers in American Samoa differs from that in the US mainland. The findings reflect significant changes in cancer incidence. Cancer control programs should evaluate the potential of uterine screening in accordance with their community's needs and characteristics.
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Neoplasias do Colo do Útero/epidemiologia , Neoplasias Uterinas/epidemiologia , Adulto , Bases de Dados Factuais , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Obesidade/epidemiologia , Estudos Retrospectivos , Samoa/epidemiologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias Uterinas/diagnósticoRESUMO
Research at safety-net hospitals may require additional planning to ensure the ethical conduct of research with vulnerable populations. This report discusses application of the principles of community-based participatory research and bioethics to establish a research partnership with a safety-net hospital in the southern U.S.
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Pesquisa Participativa Baseada na Comunidade/ética , Pesquisa Participativa Baseada na Comunidade/organização & administração , Administração Hospitalar/ética , Provedores de Redes de Segurança/ética , Temas Bioéticos , Relações Comunidade-Instituição , Disparidades nos Níveis de Saúde , Humanos , Grupos Minoritários , Provedores de Redes de Segurança/organização & administração , Fatores Socioeconômicos , Estados Unidos , Universidades , Populações VulneráveisRESUMO
BACKGROUND: To assess infertility knowledge and treatment beliefs among African American women in an urban community in Atlanta, Georgia. METHODS: This was a cross sectional study at a safety net hospital. A convenience sample of a total of 158 women receiving outpatient obstetrical or gynecologic care from March-April 2017 were recruited. Infertility knowledge and treatment beliefs were assessed using a previously applied and field-tested survey from the International Fertility Decision Making Study. RESULTS: The mean infertility knowledge score was 38.15% for total subjects. Those with a higher level of education (p < 0.0001) and those with paid employment (p = 0.01) had a significantly higher level of infertility knowledge. Those who had a history of infertility therapy were significantly more likely to agree with negative treatment beliefs (p = 0.01). There was no significant difference in infertility knowledge or treatment beliefs based on age, sexuality, parity or being pregnant at the time of survey completion. CONCLUSIONS: African American women in our urban clinic setting seem to have a limited level of knowledge pertaining to infertility. Further research is needed to understand how differences in knowledge and beliefs translate into infertility care decision-making and future childbearing.
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BACKGROUND: Even though novel therapies based on aberrant DNA methylation could be of particular importance for the treatment of cervical cancer (CC) because the oncoproteins E6/E7 of high-risk human papillomaviruses, the causative agents for developing CC, have the capacity to bind and upregulate DNA methyltransferases (DNMTs), to our knowledge, no previous studies have evaluated the expression of this enzyme in CC in relation to survival outcomes. The purpose of the study was to evaluate the expression of DNMT1 in CC and its association with survival outcomes. METHODS: The study population consisted of 76 women treated for primary CC and followed up by the University of Alabama at Birmingham (UAB) cancer registry. The expression of DNMT1 was examined using immunohistochemistry, and the degree of expression of DNMT1 was expressed as a percentage of cells positive for DNMT1 and its intensity. Cox proportional hazards model was used to assess the relationship between the degree of expression of DNMT1 and overall survival after adjusting for relevant covariates. RESULTS: The expression of DNMT1 was significantly higher in CC cells compared to that in the normal cervical epithelium. A higher percentage of cells positive for DNMT1 and a higher intensity score for DNMT1 were significantly associated with poor survival outcome (hazard ratio [HR] =4.3, P=0.03 and HR =4.9, P=0.02, respectively). CONCLUSION: Our findings suggested that the degree of expression of DNMT1 could be considered as a target in the epigenetic treatment of CC. Replication of our results in other study populations with CC could create the opportunity of using DNMT inhibitors to treat CC.
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Hereditary breast and ovarian cancer syndrome (HBOC) is an inherited condition associated with mutations in the BRCA1 or BRCA2 (BRCA) genes. Identification of individuals with HBOC requires that primary care providers understand the genetic principles required to appropriately collect family history and refer individuals for genetic evaluation. A survey was developed and administered to primary care providers in Georgia to assess their existing knowledge of HBOC and direct targeted educational efforts.We found that Georgia providers demonstrate some knowledge of basic genetic principles but were unable to consistently identify individuals at risk for HBOC. Knowledge deficits included lack of understanding of inheritance patterns and failure to recognize the significance of ovarian cancer history. Strategies for improving identification of patients with HBOC include increasing provider knowledge and integrating HBOC risk assessment tools into practice. Identification of individuals at risk is the critical first step in the process of reducing incidence of breast and ovarian cancer associated with BRCA mutations.
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Predisposição Genética para Doença , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde/educação , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Atenção Primária à Saúde , Adulto , Feminino , Genes BRCA1 , Genes BRCA2 , Georgia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Fatores de Risco , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Although urine-based testing for human papillomavirus (HPV) is being explored as a practical approach for cervical cancer screening, whether the results differ by age, race, or indicators of excess body weight or in populations exposed to HPV vaccines has not been documented by previous studies. The purpose of this study was to determine the accuracy of urinary HPV testing for the presence of cervical HPVs and high-grade cervical intraepithelial lesions (grade 2 and 3 cervical intraepithelial neoplasia [CIN]) by the aforementioned population characteristics. METHODS: The study population consisted of 502 women diagnosed with different grades of CIN. HPV testing was performed with paired urine and cervical cell DNA with the Roche Diagnostics Linear Array test. Agreement coefficient 1 and probabilities were calculated to determine the accuracy of urinary HPV testing for the presence of cervical HPVs and CIN lesions. RESULTS: Substantial to almost perfect agreement (0.66-0.83) was observed in the detection of any HPV genotype in urine specimens versus cervical specimens, regardless of the population characteristics. Although the positive predictive value for the detection of CIN lesions was relatively low, the negative predictive value for CIN-3 was high (≥90%) among women positive for any of the urinary or cervical high-risk human papillomavirus (HR-HPV) genotypes or HPV genotypes not included in currently available HPV vaccines. CONCLUSIONS: The results demonstrate that urinary HPV testing provides highly satisfactory results for excluding the possibility of any cervical HPV infections, including HPV types not included in vaccines and CIN lesions associated with any HR-HPV, regardless of a woman's age, race, or excess body weight. Cancer 2016. © 2016 American Cancer Society. Cancer 2016;122:2836-2844. © 2016 American Cancer Society.
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Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/urina , Infecções por Papillomavirus/virologia , Displasia do Colo do Útero/urina , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/urina , Neoplasias do Colo do Útero/virologia , Adulto , Detecção Precoce de Câncer , Feminino , Humanos , Papillomaviridae/genética , Neoplasias do Colo do Útero/diagnóstico , Displasia do Colo do Útero/diagnósticoRESUMO
Disparities in Cervical Cancer (CC) mortality outcomes between African American (AA) and White women have been studied for decades. However, conclusions about the effect of race on CC survival differ across studies. This study assessed differences in CC survival between AA and White women diagnosed between 1985 and 2010 and treated at two major hospitals in the southeastern US. The study sample included 925 AA and 1192 White women diagnosed with cervical adenocarcinoma, adenosquamous cell carcinoma, or squamous cell carcinoma. Propensity score adjustment and matching were employed to compare 5-year survival between the two racial groups. Crude comparisons suggested relevant racial differences in survival. However, the racial differences became of small magnitude after propensity-score adjustment and in matched analyses. Nonlinear models identified age at diagnosis, cancer stage, mode of treatment, and histological subtype as the most salient characteristics predicting 5-year survival of CC, yet these characteristics were also associated with race. Crude racial differences in survival might be partly explained by underlying differences in the characteristics of racial groups, such as age at diagnosis, histological subtype, cancer stage, and the mode of treatment. The study results highlight the need to improve access to early screening and treatment opportunities for AA women to improve posttreatment survival from CC.
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Negro ou Afro-Americano/estatística & dados numéricos , Neoplasias do Colo do Útero/mortalidade , População Branca/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , História do Século XX , História do Século XXI , Humanos , Pessoa de Meia-Idade , Sudeste dos Estados Unidos/epidemiologia , Sudeste dos Estados Unidos/etnologia , Análise de Sobrevida , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/história , Neoplasias do Colo do Útero/terapia , Adulto JovemRESUMO
â¢Aggressive course and treatment resistance characterize ectopic human chorionic gonadotropin.â¢Recurrence of endometrial cancer with ectopic hCG was treated with brachytherapy and EMACO.â¢The serum hCG level can serve as a marker in tumors with ectopic hCG expression.
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In the United States of America, prostate cancer is the second most common age-related cancer among men. African-American men have the highest incidence of, and mortality rate from this disease in the United States. According to the American Cancer Society, 29% of all cancer cases and 9% of all cancer deaths are a result of prostate cancer. Individuals who are at highest risk include African-American men, men over 60 years of age, and those with a family history of the disease. African-Americans also have twice the risk of developing prostate cancer as compared to Caucasians. Erythroblastosis virus E26 transformation-specific (ETS) factors play an important role in human cancers. ETS Variant 1 (ETV1), an ETS factor, is notable for its association in prostate cancers, where truncated ETV1 (dETV1) or its full length counterpart is overexpressed in approximately 10% of the prostate cancer patients. Prostate cancer tumorigenesis may be initiated by deregulation of the Wnt/ß-catenin pathway. Mutations that stabilize ß-catenin were shown to contribute to the loss of cell-growth control in tumorigenesis. We hypothesized that ETV1's interaction with components of the Wnt/ß-catenin pathway may alter ß-catenin's interaction with downstream tumor-suppressor genes, which are critical in regulating apoptosis and cell-growth properties of prostate cells. Our results demonstrate for the first time that ETV1 alters ß-catenin activity by activating kinases that regulate Wnt/ß-catenin activity through post-translational modification in prostate cancer cells. We further demonstrate that therapeutic agents such as PD98059, that reverse effect of ETV1 on Wnt/ß-catenin signaling pathway, can be used to target ETV1-positive prostate cancer cells. These therapeutic agents could have a profound impact on prevention and treatment of prostate cancer which may help to reduce health disparity seen in minority patients. Understanding the role of ETV1 in Wnt/ß-catenin pathway will also allow us to develop better diagnostic tools, which can be used as a biomarker for ETV1-positive prostate cancers.
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BACKGROUND: The Georgia Breast Cancer Genomic Health Consortium is a partnership created with funding from the Centers for Disease Control and Prevention (CDC) to the Georgia Department of Public Health to reduce cancer disparities among high-risk minority women. The project addresses young women at increased risk for hereditary breast and ovarian cancer (HBOC) syndrome through outreach efforts. METHODS: The consortium provides education and collects surveillance data using the breast cancer genetics referral screening tool (B-RST) available at www.BreastCancerGeneScreen.org . The HBOC educational protocol was presented to 73 staff in 6 public health centers. Staff used the tool during the collection of medical history. Further family history assessments and testing for mutations in the BRCA1/2 genes were facilitated if appropriate. RESULTS: Data was collected from November 2012 through December 2013, including 2,159 screened women. The majority of patients identified as black/African American and were 18-49 years old. Also, 6.0 % (n = 130) had positive screens, and 60.9 % (n = 67) of the 110 patients who agreed to be contacted provided a detailed family history. A total of 47 patients (42.7 %) met National Comprehensive Cancer Network guidelines when family history was clarified. Fourteen (12.7 %) underwent genetic testing; 1 patient was positive for a BRCA2 mutation, and 1 patient was found to carry a variant of uncertain significance. CONCLUSIONS: The introduction of genomics practice within public health departments has provided access to comprehensive cancer care for uninsured individuals. The successful implementation of the B-RST into public health centers demonstrates the opportunity for integration of HBOC screening into primary care practices.
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Proteína BRCA1/genética , Proteína BRCA2/genética , Detecção Precoce de Câncer , Predisposição Genética para Doença , Mutação/genética , Programas Nacionais de Saúde/legislação & jurisprudência , Neoplasias Ovarianas/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Feminino , Seguimentos , Implementação de Plano de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Prognóstico , Estados Unidos/epidemiologia , Adulto JovemRESUMO
Significant cancer health disparities exist in the United States and Puerto Rico. While numerous initiatives have been implemented to reduce cancer disparities, regional coordination of these efforts between institutions is often limited. To address cancer health disparities nation-wide, a series of regional transdisciplinary networks through the Geographic Management Program (GMaP) and the Minority Biospecimen/Biobanking Geographic Management Program (BMaP) were established in six regions across the country. This paper describes the development of the Region 3 GMaP/BMaP network composed of over 100 investigators from nine institutions in five Southeastern states and Puerto Rico to develop a state-of-the-art network for cancer health disparities research and training. We describe a series of partnership activities that led to the formation of the infrastructure for this network, recount the participatory processes utilized to develop and implement a needs and assets assessment and implementation plan, and describe our approach to data collection. Completion, by all nine institutions, of the needs and assets assessment resulted in several beneficial outcomes for Region 3 GMaP/BMaP. This network entails ongoing commitment from the institutions and institutional leaders, continuous participatory and engagement activities, and effective coordination and communication centered on team science goals.
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Acessibilidade aos Serviços de Saúde/normas , Disparidades nos Níveis de Saúde , Disparidades em Assistência à Saúde/normas , Saúde das Minorias/normas , Neoplasias/prevenção & controle , Regionalização da Saúde/normas , Negro ou Afro-Americano/estatística & dados numéricos , Redes Comunitárias/organização & administração , Acessibilidade aos Serviços de Saúde/organização & administração , Disparidades em Assistência à Saúde/organização & administração , Hispânico ou Latino/estatística & dados numéricos , Humanos , Relações Interinstitucionais , Saúde das Minorias/estatística & dados numéricos , Avaliação das Necessidades/organização & administração , Avaliação das Necessidades/normas , Neoplasias/diagnóstico , Neoplasias/etnologia , Porto Rico/epidemiologia , Regionalização da Saúde/métodos , Regionalização da Saúde/organização & administração , Sudeste dos Estados Unidos/epidemiologiaRESUMO
Cancer therapies are known to alter the reproductive potential in cancer patients. Due to improved survival rates in cancer patients of reproductive age, considerations of the long-term effects of cancer therapy have become more significant. Oncofertility is a new discipline in medicine that deals with maintaining the reproductive potential of cancer patients while they are receiving gonadotoxic cancer treatment. The purpose of this review is to explore how cancer treatment impairs reproductive functioning and present the current options for preservation of fertility in women. All patients with reproductive potential should be made aware of the possible treatment-related infertility and be offered appropriate fertility preservation options before cancer treatment is instituted. The hope is that, in the future, mechanism(s) can be developed to preserve immature germ cells in the ovary, so that they can be used for fertilization in vivo or in vitro.
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Preservação da Fertilidade/métodos , Infertilidade Feminina/prevenção & controle , Neoplasias/terapia , Adulto , Feminino , Neoplasias dos Genitais Femininos/terapia , HumanosRESUMO
Transforming growth factor beta (TGF-ß) signaling pathway is involved in diverse cellular processes, including cell proliferation, differentiation, adhesion, apoptosis, and some human diseases including cancer. Smad proteins function as mediators of intracellular signal transduction of TGF-ß. Following their phosphorylation by TGF-ß receptor I, Smad2 and Smad3 form a heteromeric complex with Smad4 and then are translocated into the nucleus where they bind to other co-factors and regulate the expression of target genes. ERG (Ets Related Gene) belongs to the ETS family of transcriptional factors. Chromosomal rearrangement of TMPRSS2 gene and ERG gene has been found in the majority of prostate cancers. Over-expression of full length or truncated ERG proteins is associated with a higher rate of recurrence and unfavorable prognosis. In this review, we focus on recent understanding of regulation of TGF-ß/Smads signaling pathway by ERG proteins in prostate cancer.
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Mammalian ovarian follicular development is tightly regulated by crosstalk between cell death and survival signals, which include both endocrine and intra-ovarian regulators. Whether the follicle ultimately ovulates or undergoes atresia is dependent on the expression and actions of factors promoting follicular cell proliferation, differentiation or apoptosis. Prohibitin (PHB) is a highly conserved, ubiquitous protein that is abundantly expressed in granulosa cells (GCs) and associated with GC differentiation and apoptosis. The current study was designed to characterize the regulation of anti-apoptotic and pro-apoptotic factors in undifferentiated rat GCs (gonadotropin independent phase) governed by PHB. Microarray technology was initially employed to identify potential apoptosis-related genes, whose expression levels within GCs were altered by either staurosporine (STS) alone or STS in presence of ectopically over-expressed PHB. Next, immunoblot studies were performed to examine the expression patterns of selective Bcl-2 family members identified by the microarray analysis, which are commonly regulated in the intrinsic-apoptotic pathway. These studies were designed to measure protein levels of Bcl2 family in relation to expression of the acidic isoform (phosphorylated) PHB and the components of MEK-Erk1/2 pathway. These studies indicated that over-expression of PHB in undifferentiated GCs inhibit apoptosis which concomitantly results in an increased level of the anti-apoptotic proteins Bcl2 and Bclxl, reduced release of cytochrome c from mitochondria and inhibition of caspase-3 activity. In contrast, silencing of PHB expression resulted in change of mitochondrial morphology from the regular reticular network to a fragmented form, which enhanced sensitization of these GCs to the induction of apoptosis. Collectively, these studies have provided new insights on the PHB-mediated anti-apoptotic mechanism, which occurs in undifferentiated GCs through a PHB â Mek-Erk1/2 â Bcl/Bcl-xL pathway and may have important clinical implications.
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Apoptose , Células da Granulosa/citologia , Sistema de Sinalização das MAP Quinases , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Repressoras/metabolismo , Proteína bcl-X/metabolismo , Animais , Caspase 3/metabolismo , Diferenciação Celular , Citocromos c/metabolismo , Feminino , Células da Granulosa/enzimologia , Células da Granulosa/metabolismo , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Ovário/citologia , Ovário/metabolismo , Proibitinas , Proteínas Proto-Oncogênicas c-bcl-2/genética , Ratos , Ratos Sprague-Dawley , Proteínas Repressoras/genética , Proteína bcl-X/genéticaRESUMO
Triple Negative Breast Cancer (TNBC) is a heterogeneous disease that based on immunohistochemistry (IHC) is estrogen receptor (ER) negative, progesterone receptor (PR) negative and human epidermal growth factor receptor 2 (HER2) negative. TNBC is typically observed in young AA women and Hispanic women who carry a mutation in the BRCA1 gene. TNBC is characterized by a distinct molecular profile, aggressive nature and lack of targeted therapies. The purpose of this article is to review the current and future novel signalling pathways as therapeutic approaches to TNBC. Recent Identification of a new BRCA1 trafficking pathway holds promise in the future for the development of targeted therapies for TNBC.
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Mutation in the BRCA1 gene is associated with increased risk for hereditary breast and ovarian cancers. In sporadic ovarian tumors, BRCA1 dysfunction is thought to be common. BRCA1 is a nuclear-cytoplasm shuttling protein. Our group has previously reported that BRCA1 proteins, unlike K109R and cancer-predisposing mutant C61G BRCA1 proteins, bind the sole SUMO E2-conjugating enzyme Ubc9. In this study, we examined the result of altered Ubc9 binding and knockdown on the sub-cellular localization and growth inhibitory function of BRCA1 proteins in ovarian cancer cells. Using live imaging of YFP, RFP-tagged BRCA1 and BRCA1a proteins, our results show enhanced cytoplasmic localization of K109R and C61G mutant BRCA1 proteins in ES-2, NIHOVCAR3 and UWB 1.289 ovarian cancer cells. Down-regulation of Ubc9 in ovarian cancer cells using Ubc9 siRNA resulted in cytoplasmic localization of BRCA1 and BRCA1a proteins. These mutant BRCA1a proteins were impaired in their capacity to inhibit growth of ES-2 ovarian cancer cells. Several ovarian cancer cells, including a BRCA1-null ovarian cancer cell line, showed higher levels of expression of Ubc9. This is the first study demonstrating the physiological link between loss of Ubc9 binding and loss of growth suppression of disease-associated mutant BRCA1a proteins in ovarian cancer cells. BRCA1, by turning off or on Ubc9 binding, regulates growth of ovarian cancers.
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Increase in mitochondrial biogenesis has been shown to accompany brown and white adipose cell differentiation. Prohibitins (PHBs), comprised of two evolutionarily conserved proteins, prohibitin-1 (PHB1) and prohibitin-2 (PHB2), are present in a high molecular-weight complex in the inner membrane of mitochondria. However, little is known about the effect of mitochondrial PHBs in adipogenesis. In the present study, we demonstrate that the levels of both PHB1 and PHB2 are significantly increased during adipogenesis of 3T3-L1 preadipocytes, especially in mitochondria. Knockdown of PHB1 or PHB2 by oligonucleotide siRNA significantly reduced the expression of adipogenic markers, the accumulation of lipids and the phosphorylation of extracellular signal-regulated kinases. In addition, fragmentation of mitochondrial reticulum, loss of mitochondrial cristae, reduction of mitochondrial content, impairment of mitochondrial complex I activity and excessive production of ROS were observed upon PHB-silencing in 3T3-L1 cells. Our results suggest that PHBs are critical mediators in promoting 3T3-L1 adipocyte differentiation and may be the potential targets for obesity therapies.
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Adipócitos/citologia , Regulação da Expressão Gênica , Mitocôndrias/metabolismo , Proteínas Repressoras/fisiologia , Células 3T3-L1 , Animais , Diferenciação Celular , Linhagem Celular , DNA Mitocondrial/metabolismo , Inativação Gênica , Humanos , Camundongos , Microscopia Confocal/métodos , Microscopia Eletrônica de Transmissão/métodos , Oligonucleotídeos/genética , Proibitinas , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio , Proteínas Repressoras/genéticaRESUMO
Prohibitins are members of a highly conserved eukaryotic protein family containing the stomatin/prohibitin/flotillin/HflK/C (SPFH) domain (also known as the prohibitin (PHB) domain) found in divergent species from prokaryotes to eukaryotes. Prohibitins are found in unicellular eukaryotes, fungi, plants, animals and humans. Prohibitins are ubiquitously expressed and present in multiple cellular compartments including the mitochondria, nucleus, and the plasma membrane, and shuttles between the mitochondria, cytosol and nucleus. Multiple functions have been attributed to the mitochondrial and nuclear prohibitins, including cellular differentiation, anti-proliferation, and morphogenesis. In the present review, we focus on the recent developments in prohibitins research related to folliculogenesis. Based on current research findings, the data suggest that these molecules play important roles in modulating specific responses of granulose cells to follicle stimulating hormone (FSH) by acting at multiple levels of the FSH signal transduction pathway. Understanding the molecular mechanisms by which the intracellular signaling pathways utilize prohibitins in governing folliculogenesis is likely to result in development of strategies to overcome fertility disorders and suppress ovarian cancer growth.