Dr. Sherif has a broad background in the fields of biochemistry, molecular genetics, cellular biology, and molecular biology through which he studied the nature and underlying causes of cancer and especially breast cancer and hepatocellular carcinoma using the Li-Fraumeni Syndrome (LFS) as a critical model system to study the mechanisms of carcinogenesis and tumorigenesis. His post-doctoral training at Stanford University under the esteemed cancer cell biologist, Esther Chang, and the subsequent training at Georgetown University provided him with exceptional technical skills to study and decipher the molecular basis and mechanisms of cancer initiation, development, and progression. As a PI on his NIH grants, he used LFS skin fibroblast cell lines to lay the groundwork (with K01 award initially) for the delineation of the tumor microenvironment that enables initiation and progression of oncogenesis through the mutation of p53, Cav-1 or DLL4 as documented in a sample of the publications listed in PubMed. As a result, his lab has identified two genes downstream of p53 whose mutated versions contribute to cell proliferation and breast cancer development. Another gene, DLL4, which we identified as missing in the cell lines of LFS family members is localized in a break-point region of a balanced reciprocal chromosomal translocation. DLL4 is a ligand that is involved in Notch signaling and is influential in the generation of hematopoietic stem cells by regulating the T cell lineage and subsequent stages of thymopoiesis. DLL4 may also be involved in cancer immune-surveillance since it is reduced or abrogated in various types of human cancer cell lines and tissues. In addition, as one of two PI’s on a multi-center CTSA project, and a U01-funded project, Dr. Sherif has administered, mentored, managed, staffed, budgeted, and successfully recruited research coordinators and patient volunteers for a collaborative study in GC/LC-MS-based metabolic analysis of human liver tissues and blood for biomarker discovery and investigation of health disparities in hepatocellular carcinoma. In this vein, he has collaborated extensively with Dr. Habtom Ressom of Georgetown University on a number of health disparity-related research projects and especially with regard to the U01 grant. He had in the past and still has collaborations with other researchers such as Drs. Ashktorab, Brim, Laiyemo, Chang, Boulares, Smulson, Sultan, etc., and produced several peer-reviewed publications. The central theme of my research studies is to develop a critical understanding of the mechanisms of carcinogenesis and tumorigenesis whether via p53 dysregulation or failure of cancer immune-surveillance or through cross-talk with the tumor microenvironment or epigenetic modifications. The results of these studies will have a major impact on the diagnosis, prognosis, and treatment of a variety of human cancers. Currently, Dr. Sherif received a huge multi-PI grant from NIH to study long COVID (PASC).