ABSTRACT This application is being submitted in response to the Notice of Special Interest (NOSI} identified as NOTCA- 22-036. The applicant parent grant is the Florida-California Cancer Research, Education & Engagement (CaRE2 } Health Equity Center at the University of Southern California (MPls: Dr. John Carpten and Dr. Mariana Stern). The CaRE2 Health Equity Center was established in 2018 through funding from the NIH/National Cancer Institute (NCI} collaborative partnership among University of Florida, Florida A&M University and University of Southern California. This bi-coastal center focused on translational disparities research among heterogeneous minority populations focusing on cancers known for high mortality, with the long-term goal of reducing cancer disparities in Blacks and Latinos and training and increasing the pool of underrepresented Black and Latino scientists conducting health disparity research. To achieve this the CaRE2 Center supports innovative translational research projects focused on understanding the biological basis of disparities in Black and Latino populations, capturing the wide heterogeneity within these two groups, with a foundational project focusing on prostate cancer (one full, one pilot). This supplement award application focuses on strengthening the capacity of an African early stage investigator (ESI} to conduct high-quality research in sub-Saharan Africa and to generate contextappropriate evidence to address the burden of CaP in that region. This is with the aim of providing highquality mentored translational cancer research to an African ESI and support the training of the ESI in developing professional competencies needed to establish a successful research career. To achieve this, we have worked with Dr Benson Nyambega {the ESI) to research project on investigating the Biological Determinants of Quality of Life Among Prostate Cancer SuNivors in Kenya and Nigeria. This research is built on the existing Molecular Biology and Clinical Biochemistry skills possessed by the ESLI with specific aims of (1) investigating Psychoneurological Symptom Cluster <PSC} classes in Kenyan and Nigerian CaP survivors and establishing the associations between classes pf this cluster and health-related quality of life <HROoL}. This rests on the hypothesis that there are within-group differences in the PSC among Black CaP survivors. The hypothesis will be investigated using the European Organization for Research and Treatment of Cancer Quality of Life Core (QoL) Questionnaire; and (2) estimating the biological determinants fallostatic load. genetic variation of Hypothalamic-Pituitary-Adrenal <HPA} axis. and tryptophan-kynurenine pathway metabolites} of mental health in Kenyan and Nigerian cohorts. This aim will test the hypothesis that the level of allostatic load, genetic variation in HPA axis genes, and kynurenine/tryptophan ratio vary by nativity and geography among Black CaP survivors and that their levels are associated with...