A Microfluidic System for Testing the Responses of Head and Neck Squamous Cell Carcinoma Tissue Biopsies to Treatment with Chemotherapy Drugs

Abstract

Tumors are heterogeneous masses of cells characterized pathologically by their size and spread. Their chaotic biology makes treatment of malignancies hard to generalize. We present a robust and reproducible glass microfluidic system, for the maintenance and "interrogation" of head and neck squamous cell carcinoma (HNSCC) tumor biopsies, which enables continuous media perfusion and waste removal, recreating in vivo laminar flow and diffusion-driven conditions. Primary HNSCC or metastatic lymph samples were subsequently treated with 5-fluorouracil and cisplatin, alone and in combination, and were monitored for viability and apoptotic biomarker release 'off-chip' over 7 days. The concentration of lactate dehydrogenase was initially high but rapidly dropped to minimally detectable levels in all tumor samples; conversely, effluent concentration of WST-1 (cell proliferation) increased over 7 days: both factors demonstrating cell viability. Addition of cell lysis reagent resulted in increased cell death and reduction in cell proliferation. An apoptotic biomarker, cytochrome c, was analyzed and all the treated samples showed higher levels than the control, with the combination therapy showing the greatest effect. Hematoxylin- and Eosin-stained sections from the biopsy, before and after maintenance, demonstrated the preservation of tissue architecture. This device offers a novel method of studying the tumor environment, and offers a pre-clinical model for creating personalized treatment regimens.

A microfluidic chip based model for the study of full thickness human intestinal tissue using dual flow

“…The initial high levels of LDH release are thought to be due to unavoidable damage caused by the handling of the tissue from the resection and then preparation for insertion into the device. [23][24][25][26]30,31 To quantify the proportion of viable cells that remained in the tissue throughout the duration of the experiment, a portion of the tissue taken from patients was immediately put into 10% v/v lysis solution for 24 h, and the total LDH release was measured. Similarly, tissue which had been in the device for 24 or 72 h was also treated in this way, and the total amounts released were quantified (Fig.…”

“…29 However, the use of microfluidics in maintaining tumour tissue has shown that such perfused systems can potentially extend this time frame with >7 days being routine in some devices. [23][24][25][26]33 As the causes of IBD remain largely unknown, many patients with the disease may develop complications which are potentially life-threatening including an increased risk of colorectal cancer. 10 There is a significant morbidity and mortality in active young people requiring elective or emergency surgery for IBD, which has a significant impact on the quality of life of sufferers.…”

“…A number of studies have shown that full thickness biopsies of various human and animal tissues can be maintained in an in vitro device that mimics the in vivo environment in a relatively simple manner. [23][24][25][26] Developed herein is a dual flow microfluidic device, designed to mimic the transport of intestinal material inside of the gut (luminal surface) through one side of the device and mimic the blood supply on the "outside" of the tissue (serosal surface) providing the necessary nutrients to maintain the viability of the tissue for a number of days after removal from a patient. The dual flow device uses a similar approach as the Ussing chamber with improvements, as well as the tissue is not crushed to be held in place, and it is not a static environment but undergoing continuous perfusion with fresh nutrients whilst simultaneously removing the waste products thereby better mimicking the in vivo environment.…”

Microfluidic Biopsy Trapping Device for the Real-Time Monitoring of Tumor Microenvironment

“…Still, the high water content (95.0–99.5%) enables sufficient exchange of essential biomolecules and metabolic end-products to maintain cell viability in a limited thickness but at the same time offers weak mechanical properties [34]. Static or diffusion-based fluidic models are provided by reservoirs on or off chip or with the fabrication of microchambers or cavities for the cell structures and nutritive media supply [35]. Other microfluidics systems deliver pulsatile flow with periods of flow and no flow or pulsations intermittently for purposes of nutritional and or drug delivery therefore delivering pressures and shear at varying levels [13, 36].…”

Integrated RNA extraction and RT-PCR for semi-quantitative gene expression studies on a microfluidic device

“…22,23 This enables investigation of the tissue as a whole or of individual cells following disaggregation. 24 Here we demonstrate the integration of RNA extraction with RT-PCR on a single microfluidic device that could be used for the analysis of tissue samples.…”