Kris pursued graduate training in Molecular and Cellular Pharmacology at the University of Miami School of Medicine under the mentorship of Izidore Lossos, MD. After receiving his PhD, Kris joined the laboratory of Anthony Letai, MD, PhD, at the Dana-Farber Cancer Institute/ Harvard Medical School for his postdoctoral fellowship.

In collaboration with others in the Letai laboratory, Kris found that some cancer cells are more primed to undergo programmed cell death (apoptosis) than others, as measured by a novel assay called BH3 Profiling (Ni Chonghaile & Sarosiek, et al., Science, 2011). Cancer cells and patient tumors that are more primed to undergo apoptosis are consequently more sensitive to chemotherapy treatment. This finding potentially explains why some patients respond favorably to chemotherapy while others do not. Kris has also utilized BH3 profiling to identify novel interaction preferences among the BCL-2 family of proteins, finding that BID preferentially activates BAK while BIM preferentially activates BAX to trigger apoptosis (Sarosiek, et al., Molecular Cell, 2013)