Title: Hepatocyte growth factor pathway expression in breast cancer by race and subtype.

Authors: Jones, Gieira S; Hoadley, Katherine A; Olsson, Linnea T; Hamilton, Alina M; Bhattacharya, Arjun; Kirk, Erin L; Tipaldos, Heather J; Fleming, Jodie M; Love, Michael I; Nichols, Hazel B; Olshan, Andrew F; Troester, Melissa A

Published In Breast Cancer Res, (2021 Aug 03)

Abstract: BACKGROUND: African American women have the highest risk of breast cancer mortality compared to other racial groups. Differences in tumor characteristics have been implicated as a possible cause; however, the tumor microenvironment may also contribute to this disparity in mortality. Hepatocyte growth factor (HGF) is a stroma-derived marker of the tumor microenvironment that may affect tumor progression differentially by race. OBJECTIVE: To examine whether an HGF gene expression signature is differentially expressed by race and tumor characteristics. METHODS: Invasive breast tumors from 1957 patients were assessed for a 38-gene RNA-based HGF gene expression signature. Participants were black (n = 1033) and non-black (n = 924) women from the population-based Carolina Breast Cancer Study (1993-2013). Generalized linear models were used to estimate the relative frequency differences (RFD) in HGF status by race, clinical, and demographic factors. RESULTS: Thirty-two percent of tumors were positive for the HGF signature. Black women were more likely [42% vs. 21%; RFD = + 19.93% (95% CI 16.00, 23.87)] to have HGF-positive tumors compared to non-black women. Triple-negative patients had a higher frequency of HGF positivity [82% vs. 13% in non-triple-negative; RFD = + 65.85% (95% CI 61.71, 69.98)], and HGF positivity was a defining feature of basal-like subtype [92% vs. 8% in non-basal; RFD = + 81.84% (95% CI 78.84, 84.83)]. HGF positivity was associated with younger age, stage, higher grade, and high genomic risk of recurrence (ROR-PT) score. CONCLUSION: HGF expression is a defining feature of basal-like tumors, and its association with black race and young women suggests it may be a candidate pathway for understanding breast cancer disparities.

PubMed ID: 34344422

MeSH Terms: Adult; Breast Neoplasms/epidemiology; Breast Neoplasms/ethnology; Breast Neoplasms/genetics*; Breast Neoplasms/pathology; Female; Health Status Disparities; Hepatocyte Growth Factor/genetics*; Humans; Middle Aged; North Carolina/epidemiology; Prevalence; Racial Groups; Signal Transduction/genetics*