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Breast cancer is the most common cancer in women in the United States (U.S.) and the leading cause of cancer related death among U.S. Hispanics/Latinas (H/Ls). H/Ls have lower rates of screening and longer time to follow up after an abnormal mammogram. We developed a comprehensive community health educator (promotores)-led education and risk identification program for Spanish-speaking H/Ls in California to increase mammography screening, genetic testing, and the understanding of the impact of family history on cancer risk. Due to COVID-19, we adapted the program to a virtual platform. The experience of transforming the program to a virtual platform provided unique opportunities for collaboration between researchers, community partners, and participants. Promotores are major partners in community based participatory research and in the provision of health care services, but their voices are often excluded from scientific reports. This commentary is an effort to provide a platform for promotores to share their experiences and for the readers to understand their approach in bridging the gap between health care services and communities.
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Neoplasias de la Mama , Humanos , Femenino , Estados Unidos , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Mamografía , Salud Pública , Hispánicos o LatinosRESUMEN
There are well-established disparities in cancer incidence and outcomes by race/ethnicity that result from the interplay between structural, socioeconomic, socio-environmental, behavioural and biological factors. However, large research studies designed to investigate factors contributing to cancer aetiology and progression have mainly focused on populations of European origin. The limitations in clinicopathological and genetic data, as well as the reduced availability of biospecimens from diverse populations, contribute to the knowledge gap and have the potential to widen cancer health disparities. In this review, we summarise reported disparities and associated factors in the United States of America (USA) for the most common cancers (breast, prostate, lung and colon), and for a subset of other cancers that highlight the complexity of disparities (gastric, liver, pancreas and leukaemia). We focus on populations commonly identified and referred to as racial/ethnic minorities in the USA-African Americans/Blacks, American Indians and Alaska Natives, Asians, Native Hawaiians/other Pacific Islanders and Hispanics/Latinos. We conclude that even though substantial progress has been made in understanding the factors underlying cancer health disparities, marked inequities persist. Additional efforts are needed to include participants from diverse populations in the research of cancer aetiology, biology and treatment. Furthermore, to eliminate cancer health disparities, it will be necessary to facilitate access to, and utilisation of, health services to all individuals, and to address structural inequities, including racism, that disproportionally affect racial/ethnic minorities in the USA.
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Disparidades en el Estado de Salud , Grupos Minoritarios/estadística & datos numéricos , Neoplasias/etnología , Etnicidad/estadística & datos numéricos , Femenino , Humanos , Masculino , Estados Unidos/etnologíaRESUMEN
Advances in understanding the mechanisms of cancer cells for evading the immune system surveillance, including how the immune system modulates the phenotype of tumours, have allowed the development of new therapies that benefit from this complex cellular network to specifically target and destroy cancer cells. Immunotherapy researchers have mainly focused on the discovery of tumour antigens that could confer specificity to immune cells to detect and destroy cancer cells, as well as on the mechanisms leading to an improved activation of effector immune cells. The Food and Drug Administration approval in 2010 of ipilumumab for melanoma treatment and of pembrolizumab in 2014, monoclonal antibodies against T-lymphocyte-associated antigen 4 and programmed cell death 1, respectively, are encouraging examples of how research in this area can successfully translate into clinical use with promising results. Currently, several ongoing clinical trials are in progress testing new anti-cancer therapies based on the enhancement of immune cell activity against tumour antigens. Here we discuss the general concepts related to immunotherapy and the recent application to the treatment of cancer with positive results that support their consideration of clinical application to patients.
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Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Antineoplásicos/uso terapéutico , Inmunoterapia/métodos , Neoplasias/terapia , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Antineoplásicos/inmunología , Ensayos Clínicos como Asunto , Humanos , Neoplasias/inmunología , Neoplasias/patologíaRESUMEN
Introduction: Breast cancer is a heterogeneous disease, and the distribution of the different subtypes varies by race/ethnic category in the United States and by country. Established breast cancer-associated factors impact subtype-specific risk; however, these included limited or no representation of Latin American diversity. To address this gap in knowledge, we report a description of demographic, reproductive, and lifestyle breast cancer-associated factors by age at diagnosis and disease subtype for The Peruvian Genetics and Genomics of Breast Cancer (PEGEN-BC) study. Methods: The PEGEN-BC study is a hospital-based breast cancer cohort that includes 1943 patients diagnosed at the Instituto Nacional de Enfermedades Neoplásicas in Lima, Peru. Demographic and reproductive information, as well as lifestyle exposures, were collected with a questionnaire. Clinical data, including tumor Hormone Receptor (HR) status and Human Epidermal Growth Factor Receptor 2 (HER2) status, were abstracted from electronic medical records. Differences in proportions and mean values were tested using Chi-squared and one-way ANOVA tests, respectively. Multinomial logistic regression models were used for multivariate association analyses. Results: The distribution of subtypes was 52% HR+HER2-, 19% HR+HER2+, 16% HR-HER2-, and 13% HR-HER2+. Indigenous American (IA) genetic ancestry was higher, and height was lower among individuals with the HR-HER2+ subtype (80% IA vs. 76% overall, p=0.007; 152 cm vs. 153 cm overall, p=0.032, respectively). In multivariate models, IA ancestry was associated with HR-HER2+ subtype (OR=1.38,95%CI=1.06-1.79, p=0.017) and parous women showed increased risk for HR-HER2+ (OR=2.7,95%CI=1.5-4.8, p<0.001) and HR-HER2- tumors (OR=2.4,95%CI=1.5-4.0, p<0.001) compared to nulliparous women. Multiple patient and tumor characteristics differed by age at diagnosis (<50 vs. >=50), including ancestry, region of residence, family history, height, BMI, breastfeeding, parity, and stage at diagnosis (p<0.02 for all variables). Discussion: The characteristics of the PEGEN-BC study participants do not suggest heterogeneity by tumor subtype except for IA genetic ancestry proportion, which has been previously reported. Differences by age at diagnosis were apparent and concordant with what is known about pre- and post-menopausal-specific disease risk factors. Additional studies in Peru should be developed to further understand the main contributors to the specific age of onset and molecular disease subtypes in this population and develop population-appropriate predictive models for prevention.
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Background: Breast cancer is the most common cancer among women in the U.S. and the leading cause of cancer death among Hispanics/Latinas (H/L). H/L are less likely than Non-H/L White (NHW) women to be diagnosed in the early stages of this disease. Approximately 5-10% of breast cancer can be attributed to inherited genetic mutations in high penetrance genes such as BRCA1/2. Women with pathogenic variants in these genes have a 40-80% lifetime risk of breast cancer. Past studies have shown that genetic counseling can help women and their families make informed decisions about genetic testing and early cancer detection or risk-reduction strategies. However, H/L are 3.9-4.8 times less likely to undergo genetic testing than NHW women. We developed a program to outreach and educate the H/L community about hereditary breast cancer, targeting monolingual Spanish-speaking individuals in California. Through this program, we have assessed cancer screening behavior and identified women who might benefit from genetic counseling in a population that is usually excluded from cancer research and care. Materials and Methods: The "Tu Historia Cuenta" program is a promotores-based virtual outreach and education program including the cities of San Francisco, Sacramento, and Los Angeles. Participants responded to three surveys: a demographic survey, a breast cancer family history survey, and a feedback survey. Survey responses were described for participants and compared by area where the program took place using chi-square, Fisher exact tests, and t tests. Multinomial logistic regression models were used for multivariate analyses. Results and Conclusion: We enrolled 1042 women, 892 completed the cancer family history survey and 62 (7%) provided responses compatible with referral to genetic counseling. We identified 272 women (42.8% ages 40 to 74 years) who were due for mammograms, 250 women (24.7% ages 25 to 65 years) due for Papanicolaou test, and 189 women (71.6% ages 50+) due for colorectal cancer screening. These results highlight the need of additional support for programs that spread awareness about cancer risk and facilitate access to resources, specifically within the H/L community.
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[This corrects the article DOI: 10.3389/fonc.2022.940162.].
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BACKGROUND: Breast cancer incidence in the United States is lower in Hispanic/Latina (H/L) compared with African American/Black or Non-Hispanic White women. An Indigenous American breast cancer-protective germline variant (rs140068132) has been reported near the estrogen receptor 1 gene. This study tests the association of rs140068132 and other polymorphisms in the 6q25 region with subtype-specific breast cancer risk in H/Ls of high Indigenous American ancestry. METHODS: Genotypes were obtained for 5,094 Peruvian women with (1,755) and without (3,337) breast cancer. Associations between genotype and overall and subtype-specific risk for the protective variant were tested using logistic regression models and conditional analyses, including other risk-associated polymorphisms in the region. RESULTS: We replicated the reported association between rs140068132 and breast cancer risk overall [odds ratio (OR), 0.53; 95% confidence interval (CI), 0.47-0.59], as well as the lower odds of developing hormone receptor negative (HR-) versus HR+ disease (OR, 0.77; 95% CI, 0.61-0.97). Models, including HER2, showed further heterogeneity with reduced odds for HR+HER2+ (OR, 0.68; 95% CI, 0.51-0.92), HR-HER2+ (OR, 0.63; 95% CI, 0.44-0.90) and HR-HER2- (OR, 0.77; 95% CI, 0.56-1.05) compared with HR+HER2-. Inclusion of other risk-associated variants did not change these observations. CONCLUSIONS: The rs140068132 polymorphism is associated with decreased risk of breast cancer in Peruvians and is more protective against HR- and HER2+ diseases independently of other breast cancer-associated variants in the 6q25 region. IMPACT: These results could inform functional analyses to understand the mechanism by which rs140068132-G reduces risk of breast cancer development in a subtype-specific manner. They also illustrate the importance of including diverse individuals in genetic studies.
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Neoplasias de la Mama , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etnología , Neoplasias de la Mama/genética , Cromosomas Humanos Par 6 , Femenino , Hispánicos o Latinos , Humanos , Modelos Logísticos , Perú/epidemiología , Receptor ErbB-2/genética , Receptores de Estrógenos/genética , Receptores de Progesterona/genéticaRESUMEN
Women of Latin American origin in the United States are more likely to be diagnosed with advanced breast cancer and have a higher risk of mortality than non-Hispanic White women. Studies in U.S. Latinas and Latin American women have reported a high incidence of HER2 positive (+) tumors; however, the factors contributing to this observation are unknown. Genome-wide genotype data for 1,312 patients from the Peruvian Genetics and Genomics of Breast Cancer Study (PEGEN-BC) were used to estimate genetic ancestry. We tested the association between HER2 status and genetic ancestry using logistic and multinomial logistic regression models. Findings were replicated in 616 samples from Mexico and Colombia. Average Indigenous American (IA) ancestry differed by subtype. In multivariate models, the odds of having an HER2+ tumor increased by a factor of 1.20 with every 10% increase in IA ancestry proportion (95% CI, 1.07-1.35; P = 0.001). The association between HER2 status and IA ancestry was independently replicated in samples from Mexico and Colombia. Results suggest that the high prevalence of HER2+ tumors in Latinas could be due in part to the presence of population-specific genetic variant(s) affecting HER2 expression in breast cancer. SIGNIFICANCE: The positive association between Indigenous American genetic ancestry and HER2+ breast cancer suggests that the high incidence of HER2+ subtypes in Latinas might be due to population and subtype-specific genetic risk variants.
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Neoplasias de la Mama/química , Neoplasias de la Mama/etnología , Hispánicos o Latinos/genética , Receptor ErbB-2/análisis , Adulto , Anciano , Pueblo Asiatico/etnología , Pueblo Asiatico/estadística & datos numéricos , Población Negra/etnología , Población Negra/estadística & datos numéricos , Neoplasias de la Mama/genética , Colombia/etnología , Femenino , Humanos , Indígenas Norteamericanos , Indígenas Sudamericanos , América Latina/etnología , Modelos Lineales , Modelos Logísticos , México/etnología , Persona de Mediana Edad , Perú/etnología , Receptor ErbB-2/genética , Receptores de Estrógenos/sangre , Receptores de Progesterona/sangre , Estados Unidos , Población Blanca/etnología , Población Blanca/estadística & datos numéricos , Adulto JovenRESUMEN
The last 10 years witnessed an acceleration of our understanding of what genetic factors underpin the risk of breast cancer. Rare high- and moderate-penetrance variants such as those in the BRCA genes account for a small proportion of the familial risk of breast cancer. Low-penetrance alleles are expected to underlie the remaining heritability. By now, there are about 180 genetic polymorphisms that are associated with risk, most of them of modest effect. In combination, they can be used to identify women at the lowest or highest ends of the risk spectrum, which might lead to more efficient cancer prevention strategies. Most of these variants were discovered in populations of European descent. As a result, we might be failing to discover additional polymorphisms that could explain risk in other groups. This review highlights breast cancer genetic epidemiology studies conducted in Latin America, and summarizes the information that they provide, with special attention to similarities and differences with studies in other populations. It includes studies of common variants, as well as moderate- and high-penetrance variants. In addition, it addresses the gaps that need to be bridged in order to better understand breast cancer genetic risk in Latin America.
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Neoplasias de la Mama/genética , Epidemiología Molecular/métodos , Neoplasias de la Mama/epidemiología , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo/métodos , Humanos , América LatinaRESUMEN
BACKGROUND: Mechanisms that lead to the reduced expression of BRCA1 in triple-negative breast cancer (TNBC) tumors are not fully understood. A possible cause is overexpression of miR-146a and miR-638, which regulate BRCA1 expression in other cancers. OBJECTIVE: To evaluate the expression of these microRNAs in relation to BRCA1 expression in TNBC tumors. METHODS: Expression of both microRNAs was assessed by real time qPCR using Taqman microRNA assays in TNBC tumors. Results were related to protein expression of BRCA1 and patient's survival. RESULTS: miR-146a and miR-638 were overexpressed in 36% and 59% of TNBC tumors, respectively. Overexpression was preeminent in BRCA1-deficient tumors and significantly associated to a better overall survival. CONCLUSION: Both miRNAs are potential biomarkers for improved overall survival in patients with BRCA1-deficient TNBC tumors.
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Proteína BRCA1/deficiencia , Biomarcadores de Tumor , MicroARNs/genética , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/mortalidad , Adulto , Anciano , Proteína BRCA2/genética , Línea Celular Tumoral , Receptores ErbB/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Mutación de Línea Germinal , Humanos , Persona de Mediana Edad , Clasificación del Tumor , Neoplasias de la Mama Triple Negativas/diagnóstico , Adulto JovenRESUMEN
El cáncer constituye la segunda de causa de muerte a nivel mundial y se estima será la primera, superando a las cardiovasculares. El estudio de sus bases moleculares ha permitido el desarrollo de la quimioterapia clásica, como de nuevas terapias biológicas. Si bien estos avances han redundado en un aumento en la sobrevida, no ha impactado en una menor incidencia de los casos. Esto último se debe, en parte, al desconocimiento de los múltiples factores carcinogénicos existentes y los efectos de sus interacciones para cada uno de los tumores. En este sentido, es interesante notar que, en los currículos de las escuelas de salud de las universidades chilenas, el cáncer u oncología como tal, no constituye una cátedra en sí misma, siendo sus contenidos tangencialmente abordados en distintos momentos de la formación; en biología celular, medicina interna y cirugía, entre otros. Con estos antecedentes, el propósito de este trabajo es ofrecer un propuesta sencilla y accesible para los estudiantes, respecto de los contenidos que, a nuestro juicio, son esenciales para comprender las bases biológicas de esta enfermedad y enfrentar con mejores conocimientos el ciclo clínico posterior. A continuación, el lector se encontrará con principios fundamentales de la biología humana normal (como el ciclo celular y el dogma central de la biología molecular), que permiten obtener una visión global de los mecanismos fisiológicos cuya desregulación conlleva a una neoplasia maligna. Luego se entregarán algunas definiciones amplias en relación con los conceptos de neoplasia, tumor benigno y maligno. Para, finalmente, abordar las principales etapas que permiten el desarrollo del cáncer; (i) iniciación, (ii) promoción y (iii) progresión. En esta última, se profundizará por separado, en angiogénesis, degradación de la matriz extracelular, migración y evasión de la respuesta inmune. Este trabajo no aborda materias relacionadas con la hipótesis metabólica del cáncer.
Cancer constitutes the second most common cause of death worldwide and is expected to become the leading one, even above cardiovascular diseases. The understanding of the cellular and molecular basis of cancer has led not only to the proper development of chemotherapy but also of target therapies. Although these advances are related with improved survival rates among cancer patients, it has poorly impacted its incidences. In this regard, the lack of knowledge regarding the impact that the several carcinogenic factors and their interactions have on different types of cancers may explain at least in part the difficulties to reduce incidence rates. However, is worth noticing that in several health schools of chilean universities, cancer does not constitute a formal course, being only partially approached during other courses, such as cell biology, internal medicine, and surgery. Thus, the aim of our work is to provide students a simple and resumed manuscript about essential topics necessary to understand the biological basis of cancer. First, the reader will find some fundamentals about human biology including the cell cycle and the central dogma of molecular biology, which offers an overview of the physiological mechanisms leading to malignant neoplasia. Then, we will provide current definitions of neoplasia, benign and malignant tumors are provided. Finally, the different stages of tumor progression will be approached to allow the understanding of cancer development. These stages include (i) initiation, (ii) promotion, and (iii) progression. For the last one, metastasis, angiogenesis, extracellular matrix degradation, migration, and immune evasion will also be addressed. This work will not consider the metabolic hypothesis of cancer.