PubMed | Medical Research Council Unit The Gambia, Komfo Anoyke Teaching Hospital, University of Melbourne, University of Buea and 17 more.
Type: | Journal: eLife | Year: 2017
Schwartz T.,University of Michigan |
Stark A.,Ford Motor Company |
Stark A.,Center for Health Research |
Stark A.,University of Pennsylvania |
And 17 more authors.
Cancer | Year: 2013
Background: Breast cancers that are negative for the estrogen receptor (ER), the progesterone receptor (PR), and the HER2 (human epidermal growth factor receptor 2) marker are more prevalent among African women, and the biologically aggressive nature of these triple-negative breast cancers (TNBCs) may be attributed to their mammary stem cell features. Little is known about expression of the mammary stem cell marker aldehyde dehydrogenase 1 (ALDH1) in African women. Novel data are reported regarding ALDH1 expression in benign and cancerous breast tissue of Ghanaian women. Methods: Formalin-fixed, paraffin-embedded specimens were transported from the Komfo Anoyke Teaching Hospital in Kumasi, Ghana to the University of Michigan for centralized histopathology study. Expression of ER, PR, HER2, and ALDH1 was assessed by immunohistochemistry. ALDH1 staining was further characterized by its presence in stromal versus epithelial and/or tumor components of tissue. Results: A total of 173 women contributed to this study: 69 with benign breast conditions, mean age 24 years, and 104 with breast cancer, mean age 49 years. The proportion of benign breast conditions expressing stromal ALDH1 (n = 40, 58%) was significantly higher than those with cancer (n = 44, 42.3%) (P =.043). Among the cancers, TNBC had the highest prevalence of ALDH1 expression, either in stroma or in epithelial cells. More than 2-fold higher likelihood of ALDH1 expression was observed in TNBC cases compared with other breast cancer subtypes (odds ratio = 2.38, 95% confidence interval 1.03-5.52, P =.042). Conclusions: ALDH1 expression was higher in stromal components of benign compared with cancerous lesions. Of the ER-, PR-, and HER2-defined subtypes of breast cancer, expression of ALDH1 was highest in TNBC. Cancer 2013. © 2012 American Cancer Society.
PubMed | University of Ghana, Peace and Love Hospital, Korle Bu Teaching Hospital, Komfo Anoyke Teaching Hospital and U.S. National Cancer Institute
Type: | Journal: Breast cancer research and treatment | Year: 2016
Late diagnoses and poor prognoses of breast cancer are common throughout Africa.To identify responsible factors, we utilized data from a population-based case-control study involving 1184 women with breast malignancies conducted in three hospitals in Accra and Kumasi, Ghana. Interviews focused on potential breast cancer risk factors as well as factors that might contribute to presentation delays. We calculated odds ratios (OR) and 95% confidence intervals (CI) comparing malignances with biopsy masses larger than 5cm. (62.4% of the 1027 cases with measurable lesions) to smaller lesions.In multivariate analyses, strong predictors of larger masses were limited education (OR 1.96, 95% CI 1.32-2.90
Brinton L.A.,U.S. National Institutes of Health |
Figueroa J.D.,U.S. National Institutes of Health |
Awuah B.,Komfo Anoyke Teaching Hospital |
Yarney J.,Korle Bu Teaching Hospital |
And 6 more authors.
Breast Cancer Research and Treatment | Year: 2014
Although breast cancer is a growing health problem in sub-Saharan Africa, reasons for its increased occurrence remain unclear. We reviewed the published literature to determine the magnitude of the increase in breast cancer, associated risk factors (including for breast cancer subtypes), and ways to reduce incidence and mortality. Some of the increased breast cancer occurrence likely reflects that women are living longer and adopting lifestyles that favor higher incidence rates. However, a greater proportion of breast cancers occur among pre-menopausal women as compared to elsewhere, which may reflect unique risk factors. Breast cancers diagnosed among African women reportedly include a disproportionate number of poor prognosis tumors, including hormone receptor negative, triple negative, and core basal phenotype tumors. However, it is unclear how lack of standardized methods for tissue collection, fixation, and classification contribute to these rates. Given appropriate classifications, it will be of interest to compare rates with other populations and to identify risk factors that relate to specific tumor subtypes. This includes not only risk factors that have been recognized in other populations but also some that may play unique roles among African women, such as genetic factors, microbiomata, xenoestrogens, hair relaxers, and skin lighteners. With limited opportunities for effective treatment, a focus is needed on identifying etiologic factors that may be amenable to intervention. It will also be essential to understand reasons why women delay seeking care after the onset of symptoms and for there to be educational campaigns about the importance of early detection. © Springer Science+Business Media 2014.
Proctor E.,University of Michigan |
Kidwell K.M.,University of Michigan |
Jiagge E.,University of Michigan |
Jiagge E.,Komfo Anoyke Teaching Hospital |
And 18 more authors.
Annals of Surgical Oncology | Year: 2015
Background: The androgen receptor (AR) is a commonly-expressed hormone receptor in breast cancer and may be a marker of response to targeted anti-androgen therapy, a particularly attractive option for triple-negative breast cancer (TNBC). Gene expression studies suggest that ARs may distinguish a luminal/AR TNBC subtype from stem cell-like subtypes. TNBC frequency is two to three times higher in African American and African breast cancers compared with White American and European breast cancers, yet little is known regarding TNBC subtypes in high-frequency African-ancestry populations. We evaluated ARs and the mammary stem cell marker aldehyde dehydrogenase 1 (ALDH1) among breast cancers from Ghana, Africa. Methods: Overall, 147 formalin-fixed, paraffin-embedded invasive breast cancers from the Komfo Anoyke Teaching Hospital in Ghana were studied at the University of Michigan, and analyzed immunohistochemically for estrogen receptor (ER), progesterone receptor (PR), HER2/neu, ALDH1, and AR expression. Results: The median age of patients was 45 years. Only 31 cases (21 %) were ER-positive, and 14 (10 %) were HER2-positive; 89 (61 %) were TNBCs. For the entire group, 44 % were AR-positive and 45 % were ALDH1-positive. ER/PR-positive tumors were more likely to be AR-positive compared with ER/PR-negative tumors (87 vs. 26 %; p < 0.0001), but there was no association between ALDH1 and AR expression. Among the TNBC cases, 45 % were ALDH1-positive and 24 % were AR-positive. ALDH1 positivity was associated with AR positivity within the subset of TNBC (36 vs. 14 %; p = 0.019). Conclusion: We confirmed other studies showing a high frequency of TNBC in Africa. Surprisingly, ALDH1 was found to correlate with AR expression among TNBC, suggesting that novel TNBC subtypes may exist among populations with African ancestry. © 2015, Society of Surgical Oncology.