Engineer Biomimetic Microfluidic Models to Investigate and Reprogram Tumor Associated Neutrophils for Cancer Therapy

Project Summary
Neutrophils play critical roles during different stages of tumor development. In mice, systemic depletion of
neutrophils results in decreased tumor growth in glioblastoma (GBM) and lung cancer, but promote tumor growth
in pre-metastatic lung and other solid tumors, indicating their stage-specific and tissue-dependent functions in
tumor progression. Neutrophils could also facilitate cancer cell resistance to chemotherapy, radiotherapy, and
immunotherapy in different tumors by releasing various cytokines. Despite these preclinical and animal studies
on tumor-associated neutrophils (TANs), a knowledge gap remains in our mechanistic understanding of how
human neutrophils regulate cancer progression and therapeutic resistance in GBM, due to the short life and
resistance to gene editing of neutrophils as well as technical hurdles in isolating stage-specific TANs. To address
this gap, we propose to harness the power of microfluidics and human induced pluripotent stem cells (hiPSCs)
to interrogate the diversity and plasticity of neutrophils in human GBM development. Elucidating the underlying
mechanism will also enable the much-needed development and evaluation of neutrophil-targeted cancer therapy.
Our central hypothesis here is that the microfluidic model will recapitulate the different stages of human tumor
progression, providing a platform for phenotypic and mechanistic understanding of the roles of neutrophils in
GBM development. To test this hypothesis, we will implement a novel interstitial tumor-microenvironment-on-
chip (iT-MOC), and interrogate neutrophil-mediated tumor progression and therapeutic resistance at different
GBM growth stages in Aim 1. Then in Aim 2, we will determine the morphology, polarization, life-span and
antitumor cytotoxicity of GBM-infiltrating neutrophils. In Aim 3, we will reprogram tumor-associated neutrophils
towards antitumor effector cells via genetic engineering of hiPSCs with chimeric antigen receptors (CARs) and
microRNAs (miRNAs). This is a novel approach as human neutrophils cannot be genetically modified. Successful
completion of these aims will offer an innovative platform to study the diversity and plasticity of TANs, and provide
insights into reprograming them towards antitumor effector cells and the proof-of-concept for CAR-neutrophils in
targeted cancer therapy.

Grant Number: 5R37CA265926-04
NIH Institute/Center: NIH
Principal Investigator: Xiaoping Bao