# CORE D

> **NIH NIH P01** · UNIVERSITY OF MINNESOTA · 2020 · $130,121

## Abstract

CORE D – ENZYMES & ANTIBODIES 
ABSTRACT 
 APOBEC enzymes are single-stranded DNA cytosine-to-uracil deaminases that normally protect cells from 
viral infections. One family member, APOBEC3B (A3B), is overexpressed in over half of all breast tumors and 
its mutation signature is found in 20% of primary and 50% of metastatic breast tumors. A3B overexpression 
and mutation signature have also been associated with therapy failure and poor overall survival. Our Program 
has shown that inhibition of A3B-mediated tumor evolution contributes to improved therapy outcomes in a 
mouse model of estrogen receptor-positive breast cancer. These data support our Program's unifying 
hypothesis that A3B inhibition, as an adjuvant to primary treatment options, will help to prevent detrimental 
mutation-driven outcomes such as drug resistance and metastasis. Our Program members are collaborating to 
test this hypothesis through 3 tightly integrated Projects focusing on the biology, chemical biology, and 
structural biology of A3B. These Projects are supported by 4 service Cores, including Core D – Enzymes & 
Antibodies, which has 2 specific aims: Aim 1 is to produce recombinant APOBEC enzymes and to perform 
standard DNA deaminase assays with these enzymes, which will allow standardization of APOBEC studies 
across labs and time. Aim 2 is to develop specific monoclonal antibodies for A3B and related human 
APOBEC3 enzymes. The availability of specific antibodies will move the Program's research forward and is 
important for the Program's translational goal of developing an antibody-based assay for diagnosing A3B- 
positive tumors in order to inform patient prognosis and, ultimately, therapeutic plans. The reagents resulting 
from both Aims are vital for expediting the goals of each Project, ensuring maximal rigor and reproducibility 
across Projects and collaborating labs and fueling Program collaborations and APOBEC research in the 
greater cancer research community. Overall, despite its relatively modest size, Core D is a powerful enabling 
feature of our Program.

## Key facts

- **NIH application ID:** 9993507
- **Project number:** 5P01CA234228-02
- **Recipient organization:** UNIVERSITY OF MINNESOTA
- **Principal Investigator:** Ming Li
- **Activity code:** P01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $130,121
- **Award type:** 5
- **Project period:** 2019-08-09 → 2024-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9993507

## Citation

> US National Institutes of Health, RePORTER application 9993507, CORE D (5P01CA234228-02). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9993507. Licensed CC0.

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