Abstract C037: Racial disparity in systemic growth-related oncogene-alpha (GRO-α) expression in head and neck cancer patients

Introduction: The objective of this study was to perform an analysis of cytokines reported to be upregulated in cancer patients to determine differences that may exist between Caucasians and African-Americans. Cancer biomarkers aid in identifying therapeutic targets as well as providing information on the involved signaling pathways. As African-Americans are known to present with advanced disease and have poorer survival even in nonmetastatic head and neck cancer, findings may be indicative of a potential therapeutic target for this population.

Methods: In this IRB approved study, we utilized a multiplex bead-based immunoassay by Millipore to compare serum levels of 13 cytokines (FGF-2, GM-CSF, GRO-α, IFNγ, IL-1β, IL-6, IL-8, IL-10, IL-13, IP-10, MIP-1β, TNFα and VEGF) in African-Americans and Caucasians at diagnosis of primary head and neck cancer. Cytokine expression was detected using Luminex xMAP technology with xPonent software, then analyzed using Milliplex Analyst.

Results: Growth-related oncogene-alpha (GRO-α) was the only significantly different cytokine analyzed in regard to ethnicity, where African-Americans (n=36) exhibited higher serum levels in pg/ml compared to Caucasians (n=85) (1287±303.9 and 415.5±50.1, respectively; 95% CI 453.1 to 1290; p<0.0001).

Conclusions: Systemic levels of GRO-α were higher in African-American compared to Caucasian head and neck cancer patients. There is accumulating evidence that GRO-α is overexpressed in human skin, breast, colorectal and hepatocellular cancers. GRO-α has been most notably implicated in cell proliferation, immune response, and as a regulator of tumor invasion and chemoresistance. With the present survival disparities in head and neck cancer patients, this striking overexpression warrants further study into a possible biomarker or targeted therapeutic agent for African-American patients.

Citation Format: Tara Moore-Medlin, Eleni Mijalis, Xiaohui Ma, Jerry McLarty, Glenn Mills, Cherie-Ann Nathan. Racial disparity in systemic growth-related oncogene-alpha (GRO-α) expression in head and neck cancer patients [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C037.