PROJECT SUMMARY:
Disparities in cancer outcomes in certain patient populations such as Hispanic/Latino (H/L) patients, are rooted
in part in the lack of understanding of biologic factors and mechanisms of response or resistance to novel
therapeutics. Although most patients express a willingness to participate in clinical research, only approximately
8% of adult cancer patients enroll in cancer clinical trials, and the percentage of minorities participating in clinical
trials, overall, is much lower when compared to the general population of the U.S. H/L’s, and other minority
groups, for example, continue to be under-represented in clinical trials. The under-representation of minority
groups in cancer research contributes to disparities in cancer care and outcomes by failing to provide the evidence
that clinicians and scientists need to safely treat and discover new treatments for minority patients with cancer.
This project enables an integrative analysis of demographic, and clinical data combined with multi-omics
approaches using blood samples and tissue from breast cancer patients to elucidate the differences in immune
response to breast cancer in patients of H/L race. Immune checkpoint inhibition (ICI) is a type of immunotherapy
that has revolutionized treatment for many patients with breast cancer. However, complex immunosuppressive
tumor microenvironments (TMEs) within breast cancers render them less responsive to ICIs and present
therapeutic obstacles. Specifically, recruitment of myeloid-derived suppressor cells (MDSCs) prohibit T-cell
activation and infiltration which leads to successful treatment with this class of therapeutics. We aim to
characterize differences in the suppressive TME by race and tumor subtype. Understanding these differences will
affect development of novel treatment combinations & strategies. The identification of patient populations with
higher risk disease, most likely to benefit from ICIs is of equal importance to understanding of scientific
mechanisms. H/L patients have a higher percentage of young women (<50 years old) diagnosed with breast cancer
and often with more aggressive subtypes as compared to Non-Hispanic White (NHW) patients. These differences
persist even when correcting for socioeconomic factors. Overall, this work will help provide insight about
differences in the immune TME in H/L patients with breast cancer and we will also try to determine if use of
organoids could help screen for differences in efficacy with regard to development of one of our one clinical trials
in development. We are investigating the promising therapeutic combination of a histone deacetylase inhibitor
entinostat, combined with ICIs as this targets MDSCs. If we can determine a differential response to this treatment
in H/L patient derived organoids this would provide a potential paradigm changing stratification of H/L patients
with breast cancer who stand to benefit from the effects of this novel therapy.