Development of micro fluidic based devices for studying tumour biology and evaluating treatment response in head and neck cancer biopsies

• Main Author: Sylvester, Deborah Claire
• Other Authors: Greenman, John
• Published: University of Hull 2011
• Subjects: 610; Medicine
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.586987

Head and Neck Squamous Cell Carcinoma (HNSCC) presents particular challenges to both the researcher and the clinician. Encompassing a group of tumours with distinct epidemiological and oncological behaviour, each sub site differs greatly in its management and prognosis. However, due to insufficient tissue quantities and culture techniques, research studies commonly group together different sub sites, limiting our understanding of the biological behaviour and treatment response of tumours from distinct sites. Micro fluidics relates to the science of systems that process or manipulate small amounts of fluids within micro channels. When applied in biology, the technology enables the production of simple, robust and highly versatile systems for studying cells and tissues. The aim of the work in this thesis was to maintain small biopsies of tumour in a physiological state, more comparable to the in vivo environment than traditional tissue culture techniques, for up to 9 days. This recreation of the ‘tumour microenvironment’ in vitro provided a platform for the testing of chemotherapy agents and analysing individual tumour behaviour. Initial optimisation studies were performed to demonstrate tissue viability within this novel culture method. Based on LDH excretion as a marker of cell death and WST-1 metabolism as a marker of viability, tumour and nodal biopsies from a variety of sub sites remained viable within the device until the addition of cell lysis buffer at 68 h. Histo-architectural examination of tissue incubated within the device for 96 h demonstrated that original tissue structure is largely maintained. In addition, comparison of viability between fresh and frozen tissues showed little difference, thus the clinical applicability of the technique was significantly enhanced, as biopsies could be collected and stored prior to use at a later date. Using clinically relevant combinations of chemotherapy drugs, nodal biopsies (n=50 micro chips from n=2 tumours with all experiments duplicated) were interrogated with cisplatin, 5-Fluorouracil and docetaxel within the micro device for up to 9 days. The addition of each chemotherapeutic agent resulted in increased cell death compared to control, with a synergistic effect seen when agents were given in combination; results in agreement with clinical trial data. This study demonstrates a robust and reproducible system for the maintenance and ‘interrogation’ of individual tumour biopsies. The innovative model provides a new platform for testing individual patient responses to chemotherapy, paving the way for ‘personalised’ treatment regimens.