# The mammary cell secretome as a novel biologic for triple-negative breast cancer

> **NIH NIH R21** · CORNELL UNIVERSITY · 2024 · $183,494

## Abstract

SUMMARY
Breast cancer accounts for nearly a quarter of all cancers in women and it remains the second leading cause of
cancer deaths in the US, despite substantial changes in standard of care treatments. Identifying evolutionary
mechanisms that naturally protect species from developing cancer is becoming an increasingly appreciated
approach to develop therapeutic strategies that are both efficient and non-toxic. We recently identified a cancer-
suppressing mechanism based on the secretion of bioactive factors with anti-cancer activity by mammary cells
(aka. mammosphere-derived epithelial cells or MDECs) from domesticated mammary cancer-proof mammals.
Specifically, these bioactive factors were shown to (i) induce triple negative breast cancer (TNBC) cell death,
without affecting normal human breast cells, in vitro and (ii) reduce tumorigenicity in a xenograft TNBC mouse
model in vivo. These findings led to our central hypothesis that the MDEC secretome from mammary cancer-
proof mammals has significant potential for the development of novel effective and non-toxic therapies to treat
and/or prevent breast cancer, especially the aggressive and hormone therapy-unresponsive TNBC. We now
propose to follow up on these interesting findings by further characterizing the anti-cancer activity of the MDEC
secretome in greater depth (Aim 1) and evaluating the therapeutic and/or preventative effects of the MDEC
secretome in mouse models of TNBC (Aim 2). The significance of this application lies in the novelty of the
approach being used to identify non-toxic efficient breast cancer therapeutic and/or preventative interventions
by focusing on bioactive anti-cancer factors produced by normal mammary cells from mammary cancer-proof
mammals. The proposed experiments will increase our knowledge of novel cancer-suppressing mechanisms
and will provide a solid basis for the design of effective and non-toxic therapies that can be used to fight
aggressive TNBC and/or for the development of protective factor-based therapeutics to eliminate or reduce
TNBC in high-risk populations.

## Key facts

- **NIH application ID:** 10774389
- **Project number:** 1R21CA285521-01
- **Recipient organization:** CORNELL UNIVERSITY
- **Principal Investigator:** Rebecca M Harman
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $183,494
- **Award type:** 1
- **Project period:** 2023-12-06 → 2025-11-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10774389

## Citation

> US National Institutes of Health, RePORTER application 10774389, The mammary cell secretome as a novel biologic for triple-negative breast cancer (1R21CA285521-01). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10774389. Licensed CC0.

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