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Biology subjects

Ahmed, A. H. R.

Publications and source records attributed to Ahmed, A. H. R..

2 recordsLinked to original sources

Microfluidic Tissue Array Platform for Personalized Drug Screening Using Tumor Explants or Biopsies

Despite major improvements in molecular characterization of breast cancer, current biomarkers still fall short in accurate treatment prediction. Interrogating tumor tissue ex-vivo in its native conformation is a direct strategy for guiding treatment of individual patients but presents a challenge. In this study, we developed a microfluidic tissue array (FTA) using small biopsy samples (< 1mm3) mimicking physiological flow for consistent exchange of nutrients and waste, retaining the tumor native stroma. Cell/patient-derived breast cancer xenograft tissues were maintained over 2 weeks in the array and their response to therapeutic agents, doxorubicin or neratinib, were interrogated. Drug response in the uFTA showed >2-fold reduction in tumor cell viability which corroborated tumor size shrinkage in mice bearing the same tumor load. EdU/Ki67 assays indicated selective retention of cells with higher proliferative capacity after drug treatment, underscoring in vivo clinical relevance . We have also developed a valved-FTA to increase throughput and variety of treatment conditions on the same chip. Together, this FTA can be staged as a powerful, low-cost benchtop theranostic tool for personalized cancer therapeutics compatible with FDAs New Approach Methods.

cancer biology↗

An Immune Cell Recirculation-Enabled Microfluidic Array to Study Dynamic Immunotherapeutic Activity in Recapitulated Tumor Microenvironment

The efficacy of immunotherapeutic treatment protocols to enable immune cell mediated treatment of cancer is significantly modulated in the presence of tumor microenvironment (TME) which is a key factor in providing both a physical barrier and immunosuppressive stimuli. Herein, we developed a recirculating, high-throughput microfluidic cell array to capture these crucial players - cytotoxic T cells in circulation, endothelium, and tumor stroma. The system consisted of a three-layered cell array spatially emulating TME, with T cell circulation sustained via fluidic recirculating circuits. This allowed us to study the dynamic TME/circulation system and cancer cell response thereof. The system further revealed that tumor endothelium exhibited a hindrance to T cell infiltration into the breast cancer tumor compartment, which was alleviated when treated with anti-human PD-L1 antibody. The other key stromal component, cancer associated fibroblasts, further attenuated T cell infiltration, and led to reduced apoptosis activity in cancer cells. These results confirm the capability of our tumor-on-a-chip system to recapitulate some key immune cell interactions with the reconstructed TME, along with demon-strating as the feasibility of using this system for high-throughput cancer immunotherapeutic screening.

bioengineering↗