Foluso O. Ademuyiwa

Parity and breastfeeding are protective against breast cancer in Nigerian women

As the relation between reproductive factors and breast cancer risk has not been systematically studied in indigenous women of sub-Saharan Africa, we examined this in a case–control study in Nigeria. In-person interviews were conducted using structured questionnaires to collect detailed reproductive history in 819 breast cancer cases and 569 community controls between 1998 and 2006. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI). Compared with women with menarcheal age <17 years, the adjusted OR for women with menarcheal age ⩾17 years was 0.72 (95% CI: 0.54–0.95, P=0.02). Parity was negatively associated with risk (P-trend=0.02) but age at first live birth was not significant (P=0.16). Importantly, breast cancer risk decreased by 7% for every 12 months of breastfeeding (P-trend=0.005). It is worth noting that the distribution of reproductive risk factors changed significantly from early to late birth cohorts in the direction of increasing breast cancer incidence. Our findings also highlight the heterogeneity of breast cancer aetiology across populations, and indicate the need for further studies among indigenous sub-Saharan women.

Common Breast Cancer Susceptibility Loci Are Associated with Triple-Negative Breast Cancer

Triple-negative breast cancers are an aggressive subtype of breast cancer with poor survival, but there remains little known about the etiologic factors that promote its initiation and development. Commonly inherited breast cancer risk factors identified through genome-wide association studies display heterogeneity of effect among breast cancer subtypes as defined by the status of estrogen and progesterone receptors. In the Triple Negative Breast Cancer Consortium (TNBCC), 22 common breast cancer susceptibility variants were investigated in 2,980 Caucasian women with triple-negative breast cancer and 4,978 healthy controls. We identified six single-nucleotide polymorphisms, including rs2046210 (ESR1), rs12662670 (ESR1), rs3803662 (TOX3), rs999737 (RAD51L1), rs8170 (19p13.1), and rs8100241 (19p13.1), significantly associated with the risk of triple-negative breast cancer. Together, our results provide convincing evidence of genetic susceptibility for triple-negative breast cancer.

Variants in the vitamin D pathway, serum levels of vitamin D, and estrogen receptor negative breast cancer among African-American women: a case-control study.

IntroductionAmerican women of African ancestry (AA) are more likely than European Americans (EA) to have estrogen receptor (ER)-negative breast cancer. 25-hydroxyvitamin D (25OHD) is low in AAs, and was associated with ER-negative tumors in EAs. We hypothesized that racial differences in 25OHD levels, as well as in inherited genetic variations, may contribute, in part, to the differences in tumor characteristics.MethodsIn a case (n = 928)-control (n = 843) study of breast cancer in AA and EA women, we measured serum 25OHD levels in controls and tested associations between risk and tag single nucleotide polymorphisms (SNPs) in VDR, CYP24A1 and CYP27B1, particularly by ER status.ResultsMore AAs had severe vitamin D deficiency (< 10 ng/ml) than EAs (34.3% vs 5.9%), with lowest levels among those with the highest African ancestry. Associations for SNPs differed by race. Among AAs, VDR SNP rs2239186, associated with higher serum levels of 25OHD, decreased risk after correction for multiple testing (OR = 0.53, 95% CI = 0.31-0.79, p by permutation = 0.03), but had no effect in EAs. The majority of associations were for ER-negative breast cancer, with seven differential associations between AA and EA women for CYP24A1 (p for interaction < 0.10). SNP rs27622941 was associated with a > twofold increased risk of ER-negative breast cancer among AAs (OR = 2.62, 95% CI = 1.38-4.98), but had no effect in EAs. rs2209314 decreased risk among EAs (OR = 0.38, 95% CI = 0.20-0.73), with no associations in AAs. The increased risk of ER-negative breast cancer in AAs compared to EAs was reduced and became non-significant (OR = 1.20, 95% CI = 0.80-1.79) after adjusting for these two CYP24A1 SNPs.ConclusionsThese data suggest that genetic variants in the vitamin D pathway may be related to the higher prevalence of ER-negative breast cancer in AA women.

Racial differences in genetic factors associated with breast cancer.

Breast cancer in African Americans in the US is more aggressive and has a worse outcome than breast cancer in Caucasians. Although the incidence of breast cancer among US whites is higher than among blacks, the mortality rates for blacks are much higher. Breast cancer in blacks is also associated with a more advanced stage at presentation and pathologically aggressive tumors commonly exhibiting estrogen receptor negativity, higher S-phase fractions, and higher numbers of involved lymph nodes. This paper reviews some of the genetic factors that have been shown to be associated with a difference in breast cancer outcome between African Americans and Caucasians in the US such as the BRCA1 and BRCA2 genes, p53 mutations, UGT1A1 gene polymorphisms, and HER-2/neu gene amplifications/overexpression.

Breast Cancer Racial Disparities: Unanswered Questions

Breast cancer is the most common noncutaneous cancer diagnosed in women in the United States and is second only to lung cancer as the leading cause of cancer-related mortality. Although mortality rates have been dropping steadily due to a variety of factors including improved treatment modalities and screening, substantial racial differences in outcome between blacks and whites persist. Although differences in health care utilization and access, tumor biology, and cancer management have been elucidated as possible reasons for disparities seen, it is likely that other interactions exist. The purpose of this review is, therefore, to present a comprehensive overview of the literature on racial disparities in breast cancer outcome and highlight potential causative factors that may contribute to disparities seen among blacks and whites with breast cancer. In addition, we make research recommendations by discussing some of the remaining gaps in knowledge that may lead to further understanding of disparities and consequently improved outcomes for all women with breast cancer.

A Phase I Trial of BKM120 (Buparlisib) in Combination with Fulvestrant in Postmenopausal Women with Estrogen Receptor-Positive Metastatic Breast Cancer.

Purpose: This trial was conducted to determine the maximum tolerated dose (MTD) and preliminary efficacy of buparlisib, an oral pan-class I PI3K inhibitor, plus fulvestrant in postmenopausal women with metastatic estrogen receptor positive (ER+) breast cancer. Experimental Design: Phase IA employed a 3+3 design to determine the MTD of buparlisib daily plus fulvestrant. Subsequent cohorts (phase IB and cohort C) evaluated intermittent (5/7-day) and continuous dosing of buparlisib (100 mg daily). No more than 3 prior systemic treatments in the metastatic setting were allowed in these subsequent cohorts. Results: Thirty-one patients were enrolled. MTD was defined as buparlisib 100 mg daily plus fulvestrant. Common adverse events (AE) included fatigue (38.7%), transaminases elevation (35.5%), rash (29%), and diarrhea (19.4%). C-peptide was significantly increased during treatment, consistent with on-target effect of buparlisib. Compared with intermittent dosing, daily buparlisib was associated with more frequent early onset AEs and higher buparlisib plasma concentrations. Among the 29 evaluable patients, the clinical benefit rate was 58.6% (95% CI, 40.7%–74.5%). Response was not associated with PIK3CA mutation or treatment cohort; however, loss of PTEN, progesterone receptor (PgR) expression, or mutation in TP53 was most common in resistant cases, and mutations in AKT1 and ESR1 did not exclude treatment response. Conclusions: Buparlisib plus fulvestrant is clinically active with manageable AEs in patients with metastatic ER+ breast cancer. Weekend breaks in buparlisib dosing reduced toxicity. Patients with PgR negative and TP53 mutation did poorly, suggesting buparlisib plus fulvestrant may not be adequately effective against tumors with these poor prognostic molecular features. Clin Cancer Res; 22(7); 1583–91. ©2015 AACR.

Impact of Body Mass Index on Clinical Outcomes in Triple-Negative Breast Cancer

Obesity is associated with poorer outcomes in patients with hormone receptor‐positive breast cancers. This association is not well established for women with triple‐negative breast cancers (TNBC). In this study, the prognostic effects of body mass index on clinical outcome were evaluated in patients with TNBC.

Expression of Forkhead-box protein A1, a marker of luminal A type breast cancer, parallels low Oncotype DX 21-gene recurrence scores

The Oncotype DX assay is one of the molecular tests that provide predictive and prognostic information to breast cancer patients with estrogen receptor (ER)-positive and node-negative disease. This study evaluates the association of Forkhead-box protein A1 (FOXA1) and GATA-binding protein 3 (GATA3) expressions with Oncotype DX recurrences scores in 77 cases of patients with ER-positive node-negative breast carcinomas diagnosed at Indiana University. The data were correlated with patient age, tumor size, histologic type, Scarff–Bloom–Richardson score, histologic grade, and progesterone receptor status. The median FOXA1 and GATA3 scores were 240 and 200, respectively. The Oncotype DX recurrence scores were low in 57%, intermediate in 30%, and high in 13% of cases. FOXA1 expression correlated negatively with Oncotype DX recurrence scores (P=0.004), and histologic type (P=0.0004). Oncotype DX recurrences score also correlated negatively with progesterone receptor (P=0.035) with 100% of progesterone receptor-negative cases having high or intermediate Oncotype DX scores. FOXA1 and GATA3 expressions correlated positively (P=0.014). The correlation between FOXA1 expression and Oncotype DX recurrence scores remained significant after adjusting for multiple comparisons and controlling for confounders such as histological type, grade, and progesterone receptor. A statistically significant correlation between the Oncotype DX recurrence scores and FOXA1 expression in our diverse cohort of ER-positive breast cancer patients was observed. We propose that this may represent a more cost-effective strategy to further risk stratify patients with good prognosis in whom chemotherapy may be omitted. To confirm these findings, further studies in a larger cohort of patients are warranted.

NY-ESO-1 Cancer Testis Antigen Demonstrates High Immunogenicity in Triple Negative Breast Cancer

Purpose NY-ESO-1 cancer testis (CT) antigen is an attractive candidate for immunotherapy as a result of its high immunogenicity. The aim of this study was to explore the potential for NY-ESO-1 antigen directed immunotherapy in triple negative breast cancer (TNBC) by determining the frequency of expression by immunohistochemistry (IHC) and the degree of inherent immunogenicity to NY-ESO-1. Experimental Design 168 TNBC and 47 ER+/HER2- primary breast cancer specimens were used to determine NY-ESO-1 frequency by IHC. As previous studies have shown that patients with a robust innate humoral immune response to CT antigens are more likely to develop CD8 T-cell responses to NY-ESO-1 peptides, we evaluated the degree to which patients with NY-ESO-1 expression had inherent immunogenicity by measuring antibodies. The relationship between NY-ESO-1 expression and CD8+ T lymphocytes was also examined. Results The frequency of NY-ESO-1 expression in the TNBC cohort was 16% versus 2% in ER+/HER2- patients. A higher NY-ESO-1 score was associated with a younger age at diagnosis in the TNBC patients with NY-ESO-1 expression (p = 0.026). No differences in OS (p = 0.278) or PFS (p = 0.238) by NY-ESO-1 expression status were detected. Antibody responses to NY-ESO-1 were found in 73% of TNBC patients whose tumors were NY-ESO-1 positive. NY-ESO-1 positive patients had higher CD8 counts than negative patients (p = 0.018). Conclusion NY-ESO-1 is expressed in a substantial subset of TNBC patients and leads to a high humoral immune response in a large proportion of these individuals. Given these observations, patients with TNBC may benefit from targeted therapies directed against NY-ESO-1.

Aldehyde dehydrogenase 1A1 expression in breast cancer is associated with stage, triple negativity, and outcome to neoadjuvant chemotherapy

Studies have shown that ALDH1A1 expression in the breast is associated with worse clinical outcome. ALDH1A1 inactivates cyclophosphamide, which is an integral agent in breast cancer chemotherapy regimens. The purposes of this study were to verify these results, to correlate ALDH1A1 expression with clinical outcome in patients treated with cyclophosphamide as part of the chemotherapy (adjuvant or neoadjuvant), and to evaluate ALDH1A1 as a useful marker to predict the clinical outcome of breast cancer subsets. A total of 513 primary breast cancers were studied. Tissue microarrays of the studied cases were stained with ALDH1A1. Key clinicopathological information was obtained. Disease-free survival and overall survival were calculated. Patients with neoadjuvant therapy who had substantial residual cancer burden (RCB) were included in the study. Fishers exact test and Kaplan–Meier methods were used for statistical analysis. ALDH1A1 was expressed in 53 (10%) patients, with a higher frequency in triple negative, followed by HER2+, and finally hormonal receptor+/HER2− (P<0.0001). Tumors with advanced stage, node-positive, or larger tumor size were correlated with ALDH1A1 expression (P=0.006, P<0.0001, and P=0.05, respectively). ALDH1A1 expression was also correlated with worse disease-free survival (P<0.006) and overall survival (P<0.01) in patients who were treated with neoadjuvant chemotherapy. In all, 8 of 22 (36%) received neoadjuvant chemotherapy and died of disease-expressed ALDH1A1 (P=0.008). Similarly, 8 of 23 (35%) who received neoadjuvant chemotherapy and had tumor recurrence expressed this marker (P=0.002). The risk of recurrence was fivefold greater than negative ALDH1A1 tumors. The risk of recurrence became 11-fold greater when cyclophosphamide but not trastuzumab was part of the regimen. Our results are consistent with previous studies. Moreover, we found that ALDH1A1 could be a useful marker to predict worse clinical outcome after chemotherapy in the neoadjuvant setting with substantial RCB. However, a larger cohort is required to verify our results.