Principal Investigator

John Krais, PhD

John trained in Bioengineering at the University of Pittsburgh (undergrad) and the Center for Chemical, Biological, and Materials Engineering at the University of Oklahoma (grad school) where he worked on targeted drug delivery strategies. He then did postdoctoral training at Fox Chase Cancer Center and focused on DNA damage response mechanisms and therapeutics that target those pathways. When not in the lab, John tries to spend as much time outdoors with his wife Tatiana and two Rhodesian Ridgebacks.

Lab Manager

Praba Esakky, PhD

Praba received his PhD in Biochemistry with a specialization in male reproductive biology in 2008 (NIRRH, ICMR) from University of Mumbai, India. His postdoctoral training was in developmental neurobiology at WEHI (2008-2009, Melbourne, Australia), vascular physiology at UTHSC (2009-2010, Memphis), followed by training in molecular reproductive toxicology in the dept. of OB & GYN at Washington University in St. Louis (2010-2015). Following postdoc trainings, he become a research instructor in the department (2015-2019). His research has primarily been focused on unraveling the harmful effects of environmental pollutants and germ cell toxicants such as constituents of cigarette smoke and viral pathogens like ZIKA virus on male fertility, germ cell development, birth defects in embryos and offspring, and developmental and neurobehavioral outcomes in offspring upon paternal exposure. Praba continued his research as a senior scientist to determine the role of proteins in ventricular injury and ependymal ciliary dysfunction and its impact on CSF dynamics in GMH-IVH in the dept. of neurosurgery (2019-2023). Praba’s current work strives to understand signaling mechanism behind DNA damage response in breast cancer in the dept. of medical oncology.  


Mohit Rajput, PhD

Mohit earned his Doctorate in Life Sciences from Jawaharlal Nehru University in 2022 specialization in cancer biology. During his doctoral study, he addressed the fundamental question of how membrane tyrosine kinase protein, EGFR, regulates intrinsic resistance to cancer therapeutics in prostate cancer (PCa) cells through EMT and DNA repair pathways. He found that EGFR regulates Rad51 protein expression in PCa through Erk1/2/PI3k-Akt signaling pathways, modulating the intrinsic resistance in PCa. His finding suggested that EGFR regulates both HR as well as NHEJ pathways in resistant PCa. After PhD, he joined University of North Carolina as a postdoctoral Research Associate for a year where he studied the role of Polymerase Theta in BRCA1-associated preneoplasia in advanced mouse models developed before moving to Washu. Currently, he is exploring the mechanistic insights of BRCA1 hypomorphs in repair of DNA DSBs in PARPi resistant cancer cells. When not in lab, Mohit loves playing cricket, table tennis and exploring natural landscapes.

Research Technician

Mary Claire Kendall

Mary Claire graduated from the University of Washington in Seattle with a major in General Biology and a minor in Chemistry in 2023. She also enjoys birdwatching and quilting.

Undergraduate researcher

Kate Powell

Kate is a second-year undergraduate student at Washington University in St. Louis majoring in Molecular Biology and Biochemistry and minoring in Healthcare Management.

Undergraduate researcher

Aarsh Patel

Aarsh Patel is currently a sophomore at WashU studying chemistry and drama. When he is not drowning in schoolwork, he loves to act, play Dungeons and Dragons, and support his residential college among other things. He says don’t be shy to say hi if you see him around!

Undergraduate researcher

Rohan Rao

Rohan is a second-year undergrad at WashU majoring in Biology on the Neuroscience track. Interests outside of school include playing golf, watching movies, and writing blurbs about himself for the lab.

The John T. Milliken Department of Medicine

Division of Oncology


  • McDonnell Sciences, 805
    4565 McKinley Ave
    St. Louis, MO 63110
  • 314-362-2626