PO-181 Predicting homing ability of hepatocellular carcinoma cells by using a lab-on-a-chip system

Introduction Lab-on-a-chip (LOC) systems can present cells multiple cues that cells are subjected to, including gradients of cytokines and secreted proteins from neighbouring cells, biochemical and mechanical interactions with the extracellular matrix, and direct cell-to-cell contacts in a controllable and reproducible fashion. Simulating microenvironment with LOC devices is crucial to understand metastasis preference of cancer cells especially for planning personalised therapies in hepatocellular carcinoma (HCC). Material and methods Peristaltic-pump was used to circulate HCC cells, HuH-7 and SNU-449. Survival under shear stress was analysed by fluorometric and microscopic analysis. Adhesion and proliferation were measured by live cell analysis system. HUVEC cells were used to simulate extravasation of circulating cells. BEAS2B, HS-27A and THLE-2 cells were used as homing targets to simulate bone, lung and liver, respectively. Image analysis was performed with fluorescent and confocal microscopy. Results and discussions Firstly, we determined the effect of shear stress in a time-dependent manner on adhesion and proliferation of HCC cells. Circulation under shear stress up to 30’ caused an increase in both adhesion and proliferation significantly, whereas longer exposure time has a negative effect on adhesion, proliferation and, survival. HuH-7 cells with epithelial phenotype found to gain increased survival capacity under shear stress than its mesenchymal counterpart SNU-449. Then, we investigated the homing preference of HCC cells by using a novel micro-circulation LOC device. Shear stress, microenvironmental conditions (medium, matrigel, coating, etc.), cell labels and numbers (homing, HCC) were optimised for LOC. Representation of endothelial barrier was succeeded by monolayer coating of ’flow-channel’ by HUVEC cells. HCC cells were circulated for 4 hours then LOCs were incubated for 3 days. The extravasation and homing preference of HCC cells were determined by confocal imaging. Consistent with the high frequency of intrahepatic metastasis in HCC, SNU-449 cells mostly preferred to home into the channel with normal liver cells. Conclusion Our study suggests designed LOC system has a potential to predict homing capacity and organ preference of circulating tumour cells in HCC. In addition to precision medicine applications such as drug screening, this device could be used as a three-dimensional tool for understanding tumor-microenvironment interactions with mechanistic explanations in metastasis.