Insulin resistance contributes to racial disparities in breast cancer prognosis in US women

Breast Cancer Research

Nina A. Bickell¹  Anupma Nayak²  Kezhen Fei³  Rebeca Franco³  Daliz Cruz³  Sheldon M. Feldman⁴  Elisa Port⁵  Melissa Pilewskie⁶  Tari King⁶  Neil B. Friedman⁷  Susan K. Boolbol⁸  Lydia Choi⁹  Brigid Killelea^1,10  Derek LeRoith^1,11  Irini M. Antoniou^1,11  Emily J. Gallagher^1,11 

[1]Department of Medicine, Icahn School of Medicine at Mount Sinai

[2]Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania

[3]Department of Population Health Science and Policy, Center for Health Equity & Community Engaged Research, Icahn School of Medicine at Mount Sinai

[4]Department of Surgery, Columbia University Medical Center

[5]Department of Surgery, Icahn School of Medicine at Mount Sinai

[6]Department of Surgery, Memorial Sloan Kettering Cancer Center

[7]Department of Surgery, Mercy Medical Center

[8]Department of Surgery, Mount Sinai Beth Israel

[9]Department of Surgery, Wayne State University School of Medicine

[10]Department of Surgery, Yale School of Medicine

[11]Division of Endocrinology, Diabetes and Bone Disease, Icahn School of Medicine at Mount Sinai

关键词: Breast cancer;    Cross-sectional study;    Prognosis;    Disparities;    Insulin resistance;    Insulin receptor;   

DOI  :  10.1186/s13058-020-01281-y

来源: DOAJ

【 摘 要 】

Abstract Background Racial disparities in breast cancer survival between Black and White women persist across all stages of breast cancer. The metabolic syndrome (MetS) of insulin resistance disproportionately affects more Black than White women. It has not been discerned if insulin resistance mediates the link between race and poor prognosis in breast cancer. We aimed to determine whether insulin resistance mediates in part the association between race and breast cancer prognosis, and if insulin receptor (IR) and insulin-like growth factor receptor (IGF-1R) expression differs between tumors from Black and White women. Methods We conducted a cross-sectional, multi-center study across ten hospitals. Self-identified Black women and White women with newly diagnosed invasive breast cancer were recruited. The primary outcome was to determine if insulin resistance, which was calculated using the homeostatic model assessment of insulin resistance (HOMA-IR), mediated the effect of race on prognosis using the multivariate linear mediation model. Demographic data, anthropometric measurements, and fasting blood were collected. Poor prognosis was defined as a Nottingham Prognostic Index (NPI) > 4.4. Breast cancer pathology specimens were evaluated for IR and IGF-1R expression by immunohistochemistry (IHC). Results Five hundred fifteen women were recruited (83% White, 17% Black). The MetS was more prevalent in Black women than in White women (40% vs 20%, p < 0.0001). HOMA-IR was higher in Black women than in White women (1.9 ± 1.2 vs 1.3 ± 1.4, p = 0.0005). Poor breast cancer prognosis was more prevalent in Black women than in White women (28% vs 15%. p = 0.004). HOMA-IR was positively associated with NPI score (r = 0.1, p = 0.02). The mediation model, adjusted for age, revealed that HOMA-IR significantly mediated the association between Black race and poor prognosis (β = 0.04, 95% CI 0.005–0.009, p = 0.002). IR expression was higher in tumors from Black women than in those from White women (79% vs 52%, p = 0.004), and greater IR/IGF-1R ratio was also associated with higher NPI score (IR/IGF-1R >  1: 4.2 ± 0.8 vs IR/IGF-1R = 1: 3.9 ± 0.8 vs IR/IGF-1R < 1: 3.5 ± 1.0, p < 0.0001). Conclusions In this multi-center, cross-sectional study of US women with newly diagnosed invasive breast cancer, insulin resistance is one factor mediating part of the association between race and poor prognosis in breast cancer.

【 授权许可】

Unknown