Acoustofluidic Engineering Of In-Vitro Tumor Models And Their Applications

In vitro tumor models are designed to reconstruct primary tumors for further basic oncology research,precision medicine,personalized therapy,and drug screening and development.However,reproducing tumor models including tumor structure,cellular components,and tumor microenvironment in vitro remains a great challenge.To date,two-dimensional culture systems and animal models have been the main tools in tumor reconstruction.Despite the superior versatility and high-throughput,large-scale properties of 2D cell line culture,there are still significant limitations: such as the inability to reproduce the 3D morphological structure of tumors and inefficient drug treatment accuracy.Animal models can more accurately reproduce tumor morphology.The most typical is the transplantation of patient-derived tumor tissue in immunodeficient mice,but it is limited by complex protocols,high cost and inability to construct on a large scale.To overcome the limitations of 2D culture systems and animal models,researchers have developed engineered tumor models based on 3D culture systems.This three-dimensional tumor model can well reconstruct the threedimensional structure of the tumor and can be used as the most basic unit to construct tissues and organs.This model can save a lot of cost and animals.In addition,the 3D culture system will combine the advantages of the 2D culture system and animal models,so that the tumor microenvironment and cell-cell interactions(such as the effect of stress on cancer cell behavior and immune lymphocyte killing processes)can be effectively studied and enable high-throughput drug screening and development.To further improve the performance of the 3D culture system in the construction of tumor models,we developed a platform for 3D tumor spheres with the help of microfabrication technology.The main research contents and results of this paper are as follows:We present the ability to use an acoustofluidic device to fabricate tumor heterogeneous spheroids with controllable size.The platform allows precise regulation of the proportion of cells within the tumor spheroids without the need for support materials.Moreover,we regulate the stratification of cells according to the different adhesion proteins secreted by the cells,and successfully reproduce the three-layer structure of tumor cells as the inner core,fibrocytes as the outer shell and vascular endothelial cells in the middle.Furthermore,based on this device,we reconstituted mouse mammary spheres into micron-scale spheroid models with complex morphological structures.Our acoustic assembly method is extremely helpful for the development of tissue engineering methods,drug screening evaluation or cancer biology research.We developed bulk-wave acoustofluidic chip to rapidly reconstruct threedimensional tumor aggregates and tumor immune microenvironments to study tumorimmune cell interactions.The rapid acoustic assembly of cells enables the cellular components of the tumor to be uniformly dispersed into hundreds of tumor aggregates.These aggregates can be cultured for up to seven days and maintain major cells,including tumor cells,stromal cells,and various immune lymphocytes.In addition,we characterized the infiltration of T lymphocytes in tumor tissues and evaluated their tumor-killing effect.Therefore,our sonic aggregate model has great potential for screening and discovery of immune checkpoint-based anticancer drugs.We developed a microfluidic system that generates droplets containing tumor cells for the rapid preparation of breast tumor organoids and preserves the protein phenotypic signature of essential oncogenes in patient breast tumors,enabling the system to identify and assess personality effectiveness of chemotherapy.Our microfluidic droplet system has the following significant advantages: By optimizing the air pressure pump,the patient’s rare tissue samples are not wasted,so that all cells can be used to prepare organoids;tumor types of desired size can be prepared uniformly organoids,ensuring the uniformity of drug toxicity testing;introducing Matrigel into the droplets reduces the organoid formation time and improves the success rate of organoid formation.Based on this powerful system,we can rapidly fabricate homogeneous patient-derived tumor organoids in vitro.Because tumor organoids reproduce the histological,pathological,and molecular features of the original patient’s breast cancer,they can be targeted for drug testing in individual patients.We believe that patient-derived organoids fabricated with our microfluidic droplet system can improve personalized therapy and accurately guide clinical treatment.