Cancer health disparities in racial/ethnic minorities in the United States.

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.

Admixture/fine-mapping in Brazilians reveals a West African associated potential regulatory variant (rs114066381) with a strong female-specific effect on body mass and fat mass indexes.

BACKGROUND/OBJECTIVES: Admixed populations are a resource to study the global genetic architecture of complex phenotypes, which is critical, considering that non-European populations are severely underrepresented in genomic studies. Here, we study the genetic architecture of BMI in children, young adults, and elderly individuals from the admixed population of Brazil. SUBJECTS/METHODS: Leveraging admixture in Brazilians, whose chromosomes are mosaics of fragments of Native American, European, and African origins, we used genome-wide data to perform admixture mapping/fine-mapping of body mass index (BMI) in three Brazilian population-based cohorts from Northeast (Salvador), Southeast (Bambuí), and South (Pelotas). RESULTS: We found significant associations with African-associated alleles in children from Salvador (PALD1 and ZMIZ1 genes), and in young adults from Pelotas (NOD2 and MTUS2 genes). More importantly, in Pelotas, rs114066381, mapped in a potential regulatory region, is significantly associated only in females (p = 2.76e-06). This variant is rare in Europeans but with frequencies of ~3% in West Africa and has a strong female-specific effect (95% CI: 2.32-5.65 kg/m2 per each A allele). We confirmed this sex-specific association and replicated its strong effect for an adjusted fat mass index in the same Pelotas cohort, and for BMI in another Brazilian cohort from São Paulo (Southeast Brazil). A meta-analysis confirmed the significant association. Remarkably, we observed that while the frequency of rs114066381-A allele ranges from 0.8 to 2.1% in the studied populations, it attains ~9% among women with morbid obesity from Pelotas, São Paulo, and Bambuí. The effect size of rs114066381 is at least five times higher than the FTO SNPs rs9939609 and rs1558902, already emblematic for their high effects. CONCLUSIONS: We identified six candidate SNPs associated with BMI. rs114066381 stands out for its high effect that was replicated and its high frequency in women with morbid obesity. We demonstrate how admixed populations are a source of new relevant phenotype-associated genetic variants.

BRCA1/2 mutations and risk-reducing bilateral salpingo-oophorectomy among Latinas: The UPTAKE study.

Bilateral salpingo-oophorectomy (BSO) is a risk management approach with strong evidence of mortality reduction for women with germline mutations in the tumor suppressor genes BRCA1 and BRCA2 (BRCA1/2). Few studies to date have evaluated uptake of BSO in women from diverse racial and ethnic backgrounds who carry BRCA1/2 mutations. The objective of the UPTAKE study was to explore rates and predictors of risk-reducing BSO among Latinas affected and unaffected with breast cancer who had a deleterious BRCA1/2 mutation. We recruited 100 Latina women with deleterious BRCA1/2 mutations from community hospitals, academic health systems, community, and advocacy organizations. Women completed interviews in Spanish or English. We obtained copies of genetic test reports for participants who provided signed medical release. After performing threefold cross-validation LASSO for variable selection, we used multiple logistic regression to identify demographic and clinical predictors of BSO. Among 100 participants, 68 had undergone BSO at the time of interview. Of these 68, 35 were US-born (61% of all US-born participants) and 33 were not (77% of the non-US-born participants). Among Latinas with BRCA1/2 mutations, older age (p = 0.004), personal history of breast cancer (p = 0.003), higher income (p = 0.002), and not having a full-time job (p = 0.027) were identified as variables significantly associated with uptake of BSO. Results suggest a high rate of uptake of risk-reducing BSO among a sample of Latinas with BRCA1/2 mutations living in the US. We document factors associated with BSO uptake in a diverse sample of women. Relevant to genetic counseling, our findings identify possible targets for supporting Latinas' decision-making about BSO following receipt of a positive BRCA1/2 test.

A pilot randomized trial of an educational intervention to increase genetic counseling and genetic testing among Latina breast cancer survivors.

Latinas are less likely to participate in genetic counseling (GC) and genetic testing (GT) than non-Hispanic Whites. A multisite, randomized pilot study tested a culturally targeted educational intervention to increase uptake of GC/GT among Latina breast cancer (BC) survivors (N = 52). Participants were recruited in Tampa, FL and Ponce, PR and randomized to: (a) fact sheet about BC survivorship (control) or (b) a culturally targeted educational booklet about GC/GT (intervention). Participants in the intervention condition were also offered no-cost telephone GC followed by free GT with mail-based saliva sample collection. Participants self-reported hereditary breast and ovarian cancer (HBOC) knowledge and emotional distress at baseline and 1- and 3-month follow-ups. We used logistic regression to examine differences in GC/GT uptake by study arm (primary outcome) and repeated measures ANOVA to examine the effects of study arm and time on HBOC knowledge and emotional distress (secondary outcomes). Compared to the control arm, intervention participants were more likely to complete GC (ORIntervention  = 13.92, 95% CI = 3.06-63.25, p < .01) and GT (ORIntervention  = 12.93, 95% CI = 2.82-59.20, p < .01). Study site did not predict uptake of GC (p = .08) but Ponce participants were more likely to complete GT (ORPonce  = 4.53, 95% CI = 1.04-19.72, p = .04). ANOVAs demonstrated an increase in HBOC knowledge over time across both groups (F(2,88) = 12.24, p < .01, ηp2  = 0.22). We also found a significant interaction of study arm and time, such that intervention participants demonstrated a greater and sustained (to the 3-month follow-up) increase in knowledge than control participants (F(2,88) = 3.66, p = .03, ηp2  = 0.08). No other main or interaction effects were significant (all p's> .15). Study findings demonstrate the potential of our culturally targeted print intervention. Lessons learned from this multisite pilot study for enhancing GC/GT in Latinas include the need to attend to both access to GC/GT and individual factors such as attitudes and knowledge.

Differential DNA Methylation in Prostate Tumors from Puerto Rican Men.

In 2020, approximately 191,930 new prostate cancer (PCa) cases are estimated in the United States (US). Hispanic/Latinos (H/L) are the second largest racial/ethnic group in the US. This study aims to assess methylation patterns between aggressive and indolent PCa including DNA repair genes along with ancestry proportions. Prostate tumors classified as aggressive (n = 11) and indolent (n = 13) on the basis of the Gleason score were collected. Tumor and adjacent normal tissue were annotated on H&E (Haemotoxylin and Eosin) slides and extracted by macro-dissection. Methylation patterns were assessed using the Illumina 850K DNA methylation platform. Raw data were processed using the Bioconductor package. Global ancestry proportions were estimated using ADMIXTURE (k = 3). One hundred eight genes including AOX1 were differentially methylated in tumor samples. Regarding the PCa aggressiveness, six hypermethylated genes (RREB1, FAM71F2, JMJD1C, COL5A3, RAE1, and GABRQ) and 11 hypomethylated genes (COL9A2, FAM179A, SLC17A2, PDE10A, PLEKHS1, TNNI2, OR51A4, RNF169, SPNS2, ADAMTSL5, and CYP4F12) were identified. Two significant differentially methylated DNA repair genes, JMJD1C and RNF169, were found. Ancestry proportion results for African, European, and Indigenous American were 24.1%, 64.2%, and 11.7%, respectively. The identification of DNA methylation patterns related to PCa in H/L men along with specific patterns related to aggressiveness and DNA repair constitutes a pivotal effort for the understanding of PCa in this population.

Clinical Cancer Genetics Disparities among Latinos.

The three major hereditary cancer syndromes in Latinos (Hereditary Breast and Ovarian Cancer, Familial Adenomatous Polyposis and Lynch Syndrome) have been shown to exhibit geographic disparities by country of origin suggesting admixture-based disparities. A solid infrastructure of clinical genetics geared towards diagnosis and prevention could aid in reducing the mortality of these cancer syndromes in Latinos. Currently, clinical cancer genetic services in Latin America are scarce. Moreover, limited studies have investigated the mutational spectrum of these cancer syndromes in Latinos resulting in gaps in personalized medicine affecting diagnosis, treatment and prevention. The following commentary discusses available genotype and clinical information on hereditary cancer in Latinos and highlights the limited access for cancer genetic services in Latin America including barriers to genetic testing and alternatives for providing better access to genetic services. In this review, we discuss the status of clinical genetic cancer services for both US Latinos and those Latinos living in Latin America.

Hereditary cancer syndromes in Latino populations: genetic characterization and surveillance guidelines.

Hereditary cancer predisposition syndromes comprise approximately 10% of diagnosed cancers; however, familial forms are believed to account for up to 30% of some cancers. In Hispanics, the most commonly diagnosed hereditary cancers include colorectal cancer syndromes such as, Lynch Syndrome, Familial Adenomatous Polyposis, and hereditary breast and ovarian cancer syndromes. Although the incidence of hereditary cancers is low, patients diagnosed with hereditary cancer syndromes are at high-risk for developing secondary cancers. Furthermore, the productivity loss that occurs after cancer diagnosis in these high-risk patients has a negative socio-economic impact. This review summarizes the genetic basis, phenotype characteristics, and the National Comprehensive Cancer Network's screening, testing, and surveillance guidelines for the leading hereditary cancer syndromes. The aim of this review is to promote a better understanding of cancer genetics and genetic testing in Hispanic patients.

Variability in DNA Repair Capacity Levels among Molecular Breast Cancer Subtypes: Triple Negative Breast Cancer Shows Lowest Repair.

Breast cancer (BC) is a heterogeneous disease which many studies have classified in at least four molecular subtypes: Luminal A, Luminal B, HER2-Enriched, and Basal-like (including triple-negative breast cancer, TNBC). These subtypes provide information to stratify patients for better prognostic predictions and treatment selection. Individuals vary in their sensitivities to carcinogens due to differences in their DNA repair capacity (DRC) levels. Although our previous case-control study established low DRC (in terms of NER pathway) as a BC risk factor, we aim to study this effect among the molecular subtypes. Therefore, the objectives of this study include investigating whether DRC varies among molecular subtypes and testing any association regarding DRC. This study comprised 267 recently diagnosed women with BC (cases) and 682 without BC (controls). Our results show a substantial variability in DRC among the molecular subtypes, with TNBC cases (n = 47) having the lowest DRC (p-value < 0.05). Almost 80 percent of BC cases had a DRC below the median (4.3%). Low DRC was strongly associated with the TNBC subtype (OR 7.2; 95% CI 3.3, 15.7). In conclusion, our study provides the first report on the variability among the molecular subtypes and provides a hypothesis based on DRC levels for the poor prognosis of TNBC.

Reconstructing Native American migrations from whole-genome and whole-exome data.

There is great scientific and popular interest in understanding the genetic history of populations in the Americas. We wish to understand when different regions of the continent were inhabited, where settlers came from, and how current inhabitants relate genetically to earlier populations. Recent studies unraveled parts of the genetic history of the continent using genotyping arrays and uniparental markers. The 1000 Genomes Project provides a unique opportunity for improving our understanding of population genetic history by providing over a hundred sequenced low coverage genomes and exomes from Colombian (CLM), Mexican-American (MXL), and Puerto Rican (PUR) populations. Here, we explore the genomic contributions of African, European, and especially Native American ancestry to these populations. Estimated Native American ancestry is 48% in MXL, 25% in CLM, and 13% in PUR. Native American ancestry in PUR is most closely related to populations surrounding the Orinoco River basin, confirming the Southern American ancestry of the Taíno people of the Caribbean. We present new methods to estimate the allele frequencies in the Native American fraction of the populations, and model their distribution using a demographic model for three ancestral Native American populations. These ancestral populations likely split in close succession: the most likely scenario, based on a peopling of the Americas 16 thousand years ago (kya), supports that the MXL Ancestors split 12.2kya, with a subsequent split of the ancestors to CLM and PUR 11.7kya. The model also features effective populations of 62,000 in Mexico, 8,700 in Colombia, and 1,900 in Puerto Rico. Modeling Identity-by-descent (IBD) and ancestry tract length, we show that post-contact populations also differ markedly in their effective sizes and migration patterns, with Puerto Rico showing the smallest effective size and the earlier migration from Europe. Finally, we compare IBD and ancestry assignments to find evidence for relatedness among European founders to the three populations.

The spectrum of BRCA1 and BRCA2 alleles in Latin America and the Caribbean: a clinical perspective.

Hereditary cancer predisposition gene testing allows the identification of individuals at high risk of cancer that may benefit from increased surveillance, chemoprevention, and prophylactic surgery. In order to implement clinical genetic strategies adapted to each population's needs and intrinsic genetic characteristic, this review aims to present the current status of knowledge about the spectrum of BRCA pathogenic variants in Latin American populations. We have conducted a comprehensive review of 33 studies published between 1994 and 2015 reporting the prevalence and/or spectrum of BRCA1 (OMIM 113705) and BRCA2 (OMIM 600185) variants. The combined sample size for these studies consisted of 4835 individuals from 13 countries in Latin America and the Caribbean, as well as in Hispanics in the United States. A total of 167 unique pathogenic variants have been reported in the existing literature. In unselected breast cancer cases, the prevalence ranged from 1.2 to 27.1%. Some countries presented a few recurrent pathogenic variants, while others were characterized by diverse, non-recurrent variants. The proportion of BRCA pathogenic variants shared between Hispanics in the United States and Latin American populations was estimated at 10.4%. Within Latin America and the Caribbean, 8.2% of the BRCA variants reported were present in more than one country. Countries with high prevalence of BRCA pathogenic variants may benefit from more aggressive testing strategies, while testing of recurrent variant panels might present a cost-effective solution for improving genetic testing in some, but not all, countries.

Epigenome-wide association study of prostate cancer in African American men identified differentially methylated genes.

INTRODUCTION: Men with African ancestry have the highest incidence and mortality rates of prostate cancer (PCa) worldwide. METHODS: This study aimed to identify differentially methylated genes between tumor vs. adjacent normal and aggressive vs. indolent PCa in 121 African American patients. Epigenome-wide DNA methylation patterns in tumor DNA were assessed using the human Illumina Methylation EPIC V1 array. RESULTS: Around 5,139 differentially methylated CpG-sites (q < 0.01, lΔßl > 0.2) were identified when comparing normal vs. tumor, with an overall trend of hypermethylation in prostate tumors.  Multiple representative differentially methylated regions (DMRs), including immune-related genes, such as CD40, Galectin3, OX40L, and STING, were detected in prostate tumors when compared to adjacent normal tissues. Based on an epigenetic clock model, we observed that tumors' total number of stem cell divisions and the stem cell division rate were significantly higher than adjacent normal tissues. Regarding PCa aggressiveness, 2,061 differentially methylated CpG-sites (q < 0.05, lΔßl > .05) were identified when the grade group (GG)1 was compared with GG4/5. Among these 2,061 CpG sites, 155 probes were consistently significant in more than one comparison. Among these genes, several immune system genes, such as COL18A1, S100A2, ITGA4, HLA-C, and ADCYAP1, have previously been linked to tumor progression in PCa. CONCLUSION: Several differentially methylated genes involved in immune-oncologic pathways associated with disease risk or aggressiveness were identified. In addition, 261 African American-specific differentially methylated genes related to the risk of PCa were identified. These results can shedlight on potential mechanisms contributing to PCa disparities in the African American Population.

Spectrum of somatic mutational features of colorectal tumors in ancestrally diverse populations.

Ancestrally diverse and admixed populations, including the Hispanic/Latino/a/x/e community, are underrepresented in cancer genetic and genomic studies. Leveraging the Latino Colorectal Cancer Consortium, we analyzed whole exome sequencing data on tumor/normal pairs from 718 individuals with colorectal cancer (128 Latino, 469 non-Latino) to map somatic mutational features by ethnicity and genetic ancestry. Global proportions of African, East Asian, European, and Native American ancestries were estimated using ADMIXTURE. Associations between global genetic ancestry and somatic mutational features across genes were examined using logistic regression. TP53 , APC , and KRAS were the most recurrently mutated genes. Compared to non-Latino individuals, tumors from Latino individuals had fewer KRAS (OR=0.64, 95%CI=0.41-0.97, p=0.037) and PIK3CA mutations (OR=0.55, 95%CI=0.31-0.98, p=0.043). Genetic ancestry was associated with presence of somatic mutations in 39 genes (FDR-adjusted LRT p<0.05). Among these genes, a 10% increase in African ancestry was associated with significantly higher odds of mutation in KNCN (OR=1.34, 95%CI=1.09-1.66, p=5.74×10 -3 ) and TMEM184B (OR=1.53, 95%CI=1.10-2.12, p=0.011). Among RMGs, we found evidence of association between genetic ancestry and mutation status in CDC27 (LRT p=0.0084) and between SMAD2 mutation status and AFR ancestry (OR=1.14, 95%CI=1.00-1.30, p=0.046). Ancestry was not associated with tumor mutational burden. Individuals with above-average Native American ancestry had a lower frequency of microsatellite instable (MSI-H) vs microsatellite stable tumors (OR=0.45, 95%CI=0.21-0.99, p=0.048). Our findings provide new knowledge about the relationship between ancestral haplotypes and somatic mutational profiles that may be useful in developing precision medicine approaches and provide additional insight into genomic contributions to cancer disparities. Significance: Our data in ancestrally diverse populations adds essential information to characterize mutational features in the colorectal cancer genome. These results will help enhance equity in the development of precision medicine strategies.

Genetic polymorphisms in RAD23B and XPC modulate DNA repair capacity and breast cancer risk in Puerto Rican women.

Studies have shown that DNA repair capacity (DRC) is significantly decreased in breast cancer patients, but the molecular causes of inter-individual variation in DRC are unknown. We hypothesized that genetic variation in the nucleotide excision repair pathway genes can modulate DRC and breast cancer risk in Puerto Rican women. A total of 228 breast cancer cases and 418 controls were recruited throughout Puerto Rico. For all study participants, eight single nucleotide polymorphisms (SNPs) in the genes XPC, XPD, and RAD23B were genotyped using a TaqMan PCR, and the DRC levels of UV induced-DNA damage was measured in peripheral lymphocytes using a host cell reactivation assay. After adjustment for confounders, RAD23B rs1805329 (Ala249Val) was found to be significantly associated with breast cancer risk under all models tested (P < 0.001). There was also a significant association between breast cancer risk and RAD23B rs10739234 (intronic) under the recessive model (P = 0.003, OR: 2.72, 95% CI: 1.40-5.30). In cases, there was a statistically significant difference in mean DRC per genotype for RAD23B rs1805329 (P < 0.001) and XPC rs2607775 (P = 0.002). When we modeled the combined effect of multiple SNPs that each independently affected DRC on cancer risk, we observed incremental augmentations in risk with increasing number of risk genotypes at those loci (P overall model <0.001). The increase in adverse genotypes was also correlated with a progressive decrease in DRC values. Our data indicate an additive effect of the NER SNPs on DRC and breast cancer risk in Puerto Rican women.

Piloting a Spanish-Language Web-Based Tool for Hereditary Cancer Genetic Testing.

The delivery of hereditary cancer pre-test education among Spanish-language patients is impeded by the dearth of Spanish-speaking genetic counselors. To address this gap, we evaluated a web-based genetic education tool delivered in Spanish to provide information typically discussed during an initial genetic counseling session. Spanish-speaking patients with a personal or family history of cancer were recruited at two centers in Puerto Rico and through social media. A total of 41 participants completed a survey before and after viewing the tool to measure knowledge, attitudes, and decisional empowerment. A subset of 10 participants completed a virtual semi-structured interview to assess the usability and appropriateness of the tool. Paired t-tests were calculated to evaluate changes in knowledge and attitudes. A McNemar test assessed for decisional empowerment. Interview transcripts were translated from Spanish to English and inductively coded and analyzed. Results revealed significant increases in knowledge (p < 0.001), while attitudes about genetic testing did not change (p = 0.77). The proportion of individuals who felt fully informed and empowered to decide about whether to undergo genetic testing increased from 15% to 51% (p < 0.001). Qualitative data indicated that participants found the tool easy to use with informative and valuable content. Our findings suggest this Spanish-language tool is a user-friendly and scalable solution to help inform and empower many individuals to decide about cancer genetic testing, recognizing that others may still benefit from genetic counseling prior to testing.

Behavioral beliefs about genetic counseling among high-risk Latina breast cancer survivors in Florida and Puerto Rico.

Compared with non-Hispanic White women, Latina women are less likely to receive genetic counseling (GC) and testing (GT) following BC diagnosis. This study used secondary data analysis to explore beliefs about GC among Latina BC survivors in and outside the US mainland. GC/GT-naïve, high-risk, Spanish-preferring Latina BC survivors (n = 52) in FL and PR completed the Behavioral Beliefs about GC scale. Participants reported high positive beliefs about GC (M = 4.19, SD = 0.92); the majority agreed that GC was beneficial to understand cancer risk (90%) and promote discussion (87%) in their family. Participants reported low-to-moderate scores for barriers (Ms = 1.53-3.40; SDs = 0.59-0.90). The most frequently endorsed barriers were desire for additional GC information (M = 3.44; SD = 0.90), and GC logistic concerns (M = 2.71; SD = 0.80). No statistically significant differences for barriers and benefits scales were identified by place of residence (all ps ≥ 0.12). These findings highlight the importance of delivering culturally sensitive GC information to high-risk Latina BC survivors.

Differential Expression of miRNAs Contributes to Tumor Aggressiveness and Racial Disparity in African American Men with Prostate Cancer.

Prostate cancer is the leading cancer in incidence and second leading cause of cancer mortality in US men. African American men have significantly higher incidence and mortality rates from prostate cancer than European American men. Previous studies reported that the disparity in prostate cancer survival or mortality can be explained by different biological backgrounds. microRNAs (miRNAs) regulate gene expression of their cognate mRNAs in many cancers. Therefore, miRNAs may be a potentially promising diagnostic tool. The role of miRNAs in prostate cancer aggressiveness and racial disparity has not been fully established. The goal of this study is to identify miRNAs associated with aggressiveness and racial disparity in prostate cancer. Here we report miRNAs that are associated with tumor status and aggressiveness in prostate cancer using a profiling approach. Further, downregulated miRNAs in African American tissues were confirmed by qRT-PCR. These miRNAs have also been shown to negatively regulate the expression of the androgen receptor in prostate cancer cells. This report provides a novel insight into understanding tumor aggressiveness and racial disparities of prostate cancer.

The association of DNA Repair with breast cancer risk in women. A comparative observational study.

BACKGROUND: Previous studies have found a link between a low DNA repair capacity (DRC) level and increased cancer risk. Our aim was to assess the statistical association of DRC level and breast cancer (BC) using a case-control epidemiological study in a Hispanic community. METHODS: We conducted a comparative observational study to assess the validity of DRC in detecting BC in 824 women throughout Puerto Rico. Over a 6-year period, we compared 285 women newly diagnosed with BC to 539 without BC. DRC levels were measured in lymphocytes by means of a host-cell reactivation assay. We assessed the sensitivity, specificity, and association using the receiver operating characteristic curve analysis. Multiple logistic regression-adjusted odds ratios were estimated with 95% confidence level to measure the strength of the association of DRC and BC after adjusting for all confounders simultaneously. RESULTS: Compared to women without cancer, women with BC showed an average decrease of 60% in their DRC levels (p < 0.001). Validity of the association of DRC as a measure of BC risk showed a sensitivity of 83.2% and specificity of 77.6% (p < 0.0001). CONCLUSIONS: Our results support the usefulness of DRC level as a measure of BC risk. Additional studies in other populations are needed to further verify its usefulness.

Important considerations for recruiting women to cancer genetics studies in Puerto Rico.

A goal of the Minority Institution/Cancer Center Partnership between the Ponce School of Medicine in Puerto Rico and the H. Lee Moffitt Cancer Center & Research Institute in Florida is to provide cross-cultural training in cancer research. This is achieved through a collaborative summer exchange program, which provides US students with an opportunity to conduct research in Puerto Rico. As part of this program, students recruited participants and collected data for a study to enhance the understanding of sociocultural factors among Puerto Rican women regarding genetic testing for hereditary breast/ovarian cancer. Limited studies have examined cancer genetics issues among Latinos, particularly those specific to the various Latino subgroups, such as Puerto Ricans. As a result of the student training experience, culturally appropriate strategies for the recruitment of women in Puerto Rico have been identified. These recommendations can inform the design of cancer research projects and interventions targeting the Puerto Rican population.

Provider discussion of genetic counseling among high-risk Spanish-preferring Latina breast cancer survivors.

Among high-risk breast cancer (BC) survivors, genetic counseling (GC) and genetic testing (GT) may inform cascade testing and risk management. Compared to non-Hispanic White BC survivors, Spanish-preferring Latina BC survivors are less likely to report discussing GC with a healthcare provider. However, few studies have examined Latinas' experiences with GC/GT, particularly outside of the mainland USA. This study aimed to compare frequency of provider discussion of GC between Spanish-preferring Latina BC survivors living in Florida (FL) and Puerto Rico (PR). We conducted secondary data analysis of baseline assessments from a randomized pilot of an educational intervention for Spanish-preferring Latina BC survivors. Participants (N = 52) were GC/GT-naive, but met clinical criteria for GC/GT referral. Participants self-reported sociodemographic, clinical, and cultural variables, including previous provider discussion of GC. Descriptive statistics characterized frequency of GC discussion. Logistic regression examined the relationships between sociodemographic, clinical, and cultural characteristics and GC discussion. Only 31% of participants reported previous GC discussion. More participants from PR reported having GC discussions (43% vs. 21% in the mainland USA). In multivariable analyses, greater likelihood of GC discussion was associated with PR (vs. mainland USA) residence (odds ratio [OR] = 6.00, p = .03), older age at baseline (OR = 1.19, p = .04), and younger age at BC diagnosis (OR = 0.80, p = .03). Few high-risk Spanish-preferring Latina BC survivors in the mainland USA and PR had discussed GC with their providers. These results highlight a gap in the implementation of evidence-based genetics guidelines. Provider-directed interventions may be needed to increase uptake of GC/GT among Latina BC survivors.

Some families have changes in the BRCA genes that increase their risk for developing breast cancer compared to those who do not have these gene changes. Through genetic testing, we can identify breast cancer survivors who have these gene changes so their families can take action to prevent future cancers. Breast cancer survivors who are diagnosed at a young age, or who have a strong family history of breast and ovarian cancer, are eligible for genetic counseling and BRCA testing. Yet, compared to women from other racial and ethnic groups, fewer Latina breast cancer survivors have genetic counseling and testing. This study explored frequency of healthcare providers' discussion about genetic counseling among Spanish-preferring Latina breast cancer survivors living in Florida and Puerto Rico. Although all participants were eligible, only 3 out of 10 indicated that a provider previously discussed genetic counseling with them. Participants who were living in Puerto Rico, older at study entry, or younger at the time of their breast cancer diagnosis were more likely to have discussed genetic counseling with a healthcare provider. Healthcare providers are important for identifying and referring high-risk Spanish-preferring Latinas for genetic counseling in and outside the mainland USA.

Ethnic and racial-specific differences in levels of centrosome-associated mitotic kinases, proliferative and epithelial-to-mesenchymal markers in breast cancers.

Molecular epidemiology evidence indicates racial and ethnic differences in the aggressiveness and survival of breast cancer. Hispanics/Latinas (H/Ls) and non-Hispanic Black women (NHB) are at higher risk of breast cancer (BC)-related death relative to non-Hispanic white (NHW) women in part because they are diagnosed with hormone receptor-negative (HR) subtype and at higher stages. Since the cell cycle is one of the most commonly deregulated cellular processes in cancer, we propose that the mitotic kinases TTK (or Mps1), TBK1, and Nek2 could be novel targets to prevent breast cancer progression among NHBs and H/Ls. In this study, we calculated levels of TTK, p-TBK1, epithelial (E-cadherin), mesenchymal (Vimentin), and proliferation (Ki67) markers through immunohistochemical (IHC) staining of breast cancer tissue microarrays (TMAs) that includes samples from 6 regions in the Southeast of the United States and Puerto Rico -regions enriched with NHB and H/L breast cancer patients. IHC analysis showed that TTK, Ki67, and Vimentin were significantly expressed in triple-negative (TNBC) tumors relative to other subtypes, while E-cadherin showed decreased expression. TTK correlated with all of the clinical variables but p-TBK1 did not correlate with any of them. TCGA analysis revealed that the mRNA levels of multiple mitotic kinases, including TTK, Nek2, Plk1, Bub1, and Aurora kinases A and B, and transcription factors that are known to control the expression of these kinases (e.g. FoxM1 and E2F1-3) were upregulated in NHBs versus NHWs and correlated with higher aneuploidy indexes in NHB, suggesting that these mitotic kinases may be future novel targets for breast cancer treatment in NHB women.