Biology subjects

Folch, A.

Publications and source records attributed to Folch, A..

8 recordsLinked to original sources

bioRxiv2025

BIOPRINTING OF MICRODISSECTED TUMOR CUBOIDS IN HYDROGELS

Microscale tumor models made from microdissected tumors that retain much of the original human tumor microenvironment (TME) are emerging as an alternative to preclinical animal models. We have introduced a drug testing approach that utilizes regularly-cut, cuboidal-shaped microdissected tissues, or "cuboids," as a way to maximize creation of microtissues from scarce biopsy materials. However, microtissues (e.g., cuboids, organoids, spheroids, etc.) can be difficult to place in precise locations, especially in applications that require their culture in hydrogels. Here, using cuboids from mouse tumor models, we demonstrate a simple bioprinting strategy for precise placement and immobilization of cuboids in hydrogel. We use a commercial bioprinter to bioprint-containing hydrogel into arrays of small hydrogel dots containing cuboids, or "cuboid dots," either onto a Transwell insert or into traps on a microplate. The hydrogel serves to immobilize the cuboids in place and provides a matrix to support cuboid viability. We demonstrate proof-of-concept applications for cancer drug testing and for protein profiling analysis. This approach will enable interface of cuboids with other devices, such as on top of a sensor or in a microfluidic platform. Furthermore, this automated process of dispensing and localizing cuboids (or other microtissue formats such as spheroids or organoids) could further their application to drug discovery and personalized medicine. TOC Graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=109 SRC="FIGDIR/small/671932v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@e1d020org.highwire.dtl.DTLVardef@1271797org.highwire.dtl.DTLVardef@17de734org.highwire.dtl.DTLVardef@d62b97_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2024

Microfluidic Modulation of Microvasculature in Microdissected Tumors

The microvasculature within the tumor microenvironment (TME) plays an essential role in cancer signaling beyond nutrient delivery. However, it has been challenging to control the generation and/or maintenance of microvasculature in ex vivo systems, a critical step for establishing cancer models of high clinical biomimicry. There have been great successes in engineering tissues incorporating microvasculature de novo (e.g., organoids and organs-on-chip), but these reconstituted tissues are formed with non-native cellular and molecular components that can skew certain outcomes such as drug efficacy. Microdissected tumors, on the other hand, show promise in preserving the TME, which is key for creating cancer models that can bridge the gap between bench and bedside. However, microdissected tumors are challenging to perfuse. Here, we developed a microfluidic platform that allows for perfusing the microvasculature of microdissected tumors. We demonstrate that, compared to diffusive transport, microfluidically perfused tissues feature larger and longer microvascular structures, with a better expression of CD31, a marker for endothelial cells, as analyzed by 3D imaging. This study also explores the effects of nitric oxide pathway-related drugs on endothelial cells, which are sensitive to shear stress and can activate endothelial nitric oxide synthase, producing nitric oxide. Our findings highlight the critical role of controlled perfusion and biochemical modulation in preserving tumor microvasculature, offering valuable insights for developing more effective cancer treatments.

bioengineering↗

bioRxiv2024

MICROMANIPULATION OF LIVE MICRODISSECTED TISSUES WITH A LOW-COST INTEGRATED ROBOTIC PLATFORM

The scarcity of human biopsies available for drug testing is a paramount challenge for developing new therapeutics, disease models, and personalized treatments. Microtechnologies that combine the microscale manipulation of tissues and fluids offer the exciting possibility of miniaturizing both disease models and drug testing workflows on scarce human biopsies. Unfortunately, these technologies presently require microfluidic devices or robotic dispensers that are not widely accessible. We have rapidly-prototyped an inexpensive platform based on an off-the-shelf robot that can microfluidically manipulate live microtissues into/out of culture plates without using complicated accessories such as microscopes or pneumatic controllers. The robot integrates complex functions with a simple, cost-effective and compact construction, allowing placement inside a tissue culture hood for sterile workflows. We demonstrated a proof-of-concept cancer drug evaluation workflow of potential clinical utility using patient tumor biopsies with multiple drugs on 384-well plates. Our user-friendly, low-cost platform promises to make drug testing of microtissues broadly accessible to pharmaceutical, clinical, and biological laboratories. TeaserA low-cost robot for handling microtissues and catalyzing their use in cancer drug evaluation and personalized oncology.

bioengineering↗

bioRxiv2024

Microdissected tumor cuboids: a microscale cancer model that retains a complex tumor microenvironment

To bridge the gap between bench and bedside, there is a need for more faithful models of human cancers that can recapitulate key features of the human tumor microenvironment (TME) and simultaneously facilitate large-scale drug tests. Our recently developed microdissection method optimizes the yield of large numbers of cuboidal microtissues (''cuboids '', ~(400 m)3 ) from a tumor biopsy. Here we demonstrate that cuboids from syngeneic mouse tumor models and human tumor biopsies retain a complex TME, making them amenable for drug and immunotherapy evaluation. We characterize relevant TME parameters, such as cellular architecture, cytokine secretion, proteomics profiles, and response to drug panels in multi-well arrays. Despite the cutting procedure and the time spent in culture (up to 7 days), the cuboids display strong cytokine expression and drug responses, including to immunotherapy. Overall, our results suggest that cuboids could provide essential therapeutic information for personalized oncology applications and could help the development of TME-dependent therapeutics and cancer disease models, including for clinical trials.

cancer biology↗

bioRxiv2024

Label-Free, Real-Time Monitoring of Cytochrome C Responses to Drugs in Microdissected Tumor Biopsies with a Multi-Well Aptasensor Platform

Functional assays on intact tumor biopsies can potentially complement and extend genomics-based approaches for precision oncology, drug testing, and organs-on-chips cancer disease models by capturing key determinants of therapeutic response, such as tissue architecture, tumor heterogeneity, and the tumor microenvironment. Currently, most of these assays rely on fluorescent labeling, a semi-quantitative method best suited to be a single-time-point terminal assay or labor-intensive terminal immunostaining analysis. Here, we report integrated aptamer electrochemical sensors for on-chip, real-time monitoring of increases of cytochrome C, a cell death indicator, from intact microdissected tissues with high affinity and specificity. The platform features a multi-well sensor layout and a multiplexed electronic setup. The aptasensors measure increases in cytochrome C in the supernatant of mouse or human microdissected tumors after exposure to various drug treatments. Since the aptamer probe can be easily exchanged to recognize different targets, the platform could be adapted for multiplexed monitoring of various biomarkers, providing critical information on the tumor and its microenvironment. This approach could not only help develop more advanced cancer disease models but also apply to other complex in vitro disease models, such as organs-on-chips and organoids.

bioengineering↗

bioRxiv2022

A 96-WELL VALVED MICROFLUIDIC DEVICE FOR TESTING OF LIVE INTACT TUMOR CUBOIDS

There is a pressing need for functional testing platforms that use human, live tumor tissue to better predict traditional and immunotherapy responses. Such platforms should also retain as much of the native tumor microenvironment (TME) as possible, as many cancer drug actions rely on TME-dependent mechanisms. Present high-throughput testing platforms that have some of these features, e.g. based on patient-derived tumor organoids, require a growth step that alters the TME. On the other hand, micro-dissected tumor tissue "spheroids" that retain an intact TME have shown promising responses to immunomodulators acting on native immune cells. Here we demonstrate a microfluidic 96-well platform designed for drug treatment of hundreds of similarly-sized, cuboidal micro-tissues ("cuboids") produced from a single tumor sample. Four cuboids per well are automatically arrayed into the platform using hydrodynamic trapping. The microfluidic device, entirely fabricated in thermoplastics, features microvalves that fluidically isolate each well after the cuboid loading step. Since the platform effectively makes the most of scarce tumor tissue, we believe it could ultimately be applied to human biopsies for drug discovery and personalized oncology, altogether bypassing animal testing.

bioengineering↗

bioRxiv2020

A Microfluidic Platform for Functional Testing of Cancer Drugs on Intact Tumor Slices

Present approaches to assess cancer treatments are often inaccurate, costly, and/or cumbersome. Functional testing platforms that use live tumor cells are a promising tool both for drug development and for identifying the optimal therapy for a given patient, i.e. precision oncology. However, current methods that utilize patient-derived cells from dissociated tissue typically lack the microenvironment of the tumor tissue and/or cannot inform on a timescale rapid enough to guide decisions for patient-specific therapy. We have developed a microfluidic platform that allows for multiplexed drug testing of intact tumor slices cultured on a porous membrane. The device is digitally-manufactured in a biocompatible thermoplastic by laser-cutting and solvent bonding. Here we describe the fabrication process in detail, we characterize the fluidic performance of the device, and demonstrate on-device drug-response testing with tumor slices from xenografts and from a patient colorectal tumor.

bioengineering↗

bioRxiv2020

Multiplexed drug testing of tumor slices using a microfluidic platform

Current methods to assess the drug response of individual human cancers are often inaccurate, costly, or slow. Functional approaches that rapidly and directly assess the response of patient cancer tissue to drugs or small molecules offer a promising way to improve drug testing, and have the potential to identify the best therapy for individual patients. We developed a digitally-manufactured microfluidic platform for multiplexed drug testing of intact cancer slice cultures, and demonstrate the use of this platform to evaluate drug responses in slice cultures from human glioma xenografts and patient tumor biopsies. This approach retains much of the tissue microenvironment and can provide results rapidly enough, within days of surgery, to guide the choice of effective initial therapies. Our results establish a useful preclinical platform for cancer drug testing and development with the potential to improve cancer personalized medicine.

bioengineering↗