# DEFINING HOW COOPERATION BETWEEN TUMOR SUBPOPULATIONS PROMOTES TUMOR PROGRESSION

> **NIH NIH R01** · GEORGETOWN UNIVERSITY · 2021 · $347,318

## Abstract

Understanding how intratumor phenotypic heterogeneity promotes disease progression is essential to improve
patient care. In this proposal we focus on the cooperative relationships between distinct tumor subpopula-
tions, which are a critical yet poorly understood property of heterogeneity within tumors. We have recently
uncovered a new symbiotic relationship between tumors subpopulations that promotes a transition from be-
nign to malignant growth by inducing the collective invasion of cohesive groups of cells. Through analysis of
the intrinsic heterogeneity within cell communities, we discovered an epigenetically distinct subpopulation of
breast cancer “trailblazer” cells that has an enhanced ability to initiate collective invasion. Importantly, sibling
“opportunist” cells can invade through paths in the ECM created by a minority subpopulation of trailblazer
cells. This democratization of invasive behavior through subpopulation cooperation eliminates a bottleneck in
tumor evolution, thus unleashing the metastatic potential of a more diverse tumor cell population. We have
begun uncovering components of a unique multi-gene regulatory program that is specifically required for trail-
blazer cell induced collective invasion and found evidence that it is active in patients with shorter survival
times. Thus, we have revealed that the activation of a new signaling network in a subpopulation of cells can
induce the formation of a novel cooperative relationship that yields widespread collective invasion and has the
potential to negatively impact patient survival. Defining factors that control this new “trailblazer” regulatory
program and determining precisely how the interaction between trailblazer and opportunist cells contributes to
cancer progression is necessary to explain how cooperative invasive behavior influences patient prognosis and
reveal treatment options. Our overall objective in this proposal is to define how trailblazer and opportunist
subpopulations influence tumor development. Our central hypothesis is that slow-cycling trailblazer cells in-
duce metastasis by promoting the opportunistic invasion of a distinct subpopulation of metastasis initiating
cells that lacks autonomous invasive ability. We will test our hypothesis and accomplish our objectives by: (1)
defining factors that control the conversion between opportunist and trailblazer states; (2) determining how
induction of the trailblazer state influences cell autonomous fitness and (3) determining how the cooperative
relationship established between trailblazer and opportunist subpopulations contributes to metastasis. From
our investigation, we expect to determine a new way in which heterogeneity promotes tumor development by
revealing how the cancer hallmarks of proliferation and autonomous invasion can be distributed across distinct
populations and shared in a synergistic relationship that promotes disease progression. These findings will
support the development of a new mode of p...

## Key facts

- **NIH application ID:** 10247474
- **Project number:** 5R01CA218670-06
- **Recipient organization:** GEORGETOWN UNIVERSITY
- **Principal Investigator:** Gray W Pearson
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $347,318
- **Award type:** 5
- **Project period:** 2017-08-11 → 2023-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10247474

## Citation

> US National Institutes of Health, RePORTER application 10247474, DEFINING HOW COOPERATION BETWEEN TUMOR SUBPOPULATIONS PROMOTES TUMOR PROGRESSION (5R01CA218670-06). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10247474. Licensed CC0.

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