Background

Metastatic progression accounts for nearly 90% of cancer-related deaths and has been directly correlated with the presence of circulating tumor cells (CTCs) in numerous carcinomas, including breast, lung, ovarian, colorectal, and head and neck cancers. The removal of CTCs from cancer patients' blood is directly implicated in the reduction of extravasation and disease invasiveness to secondary organs.

Methods

We designed and printed 3-dimensional (3D) microchannel devices using a biocompatible polymer and packed them with anti-EpCAM (EpCAM) mediated glass-based (G) compositions (G-EpCAM). Computational fluid dynamic (CFD) analysis simulation was explored to optimize the hemodynamic effect of the G-EpCAM device for measuring the pressure and velocity difference for blood along the spiral flow microchannels.

Red blood cell (RBC) hemolysis was estimated using G-EpCAM compositions packed in a device to determine optimal biocompatibility. We assessed cancer cell lines' (breast cancer MCF7, lung cancer A549) interactions and capture with varying incubation time points, the effect of anti-EpCAM concentrations, the number of G-EpCAMs, and series of devices. We evaluated the G-EpCAM-on-device's CTC capture capability and biocompatibility using head and neck, colorectal, lung, and ductal breast cancer patients' blood samples. All G-EpCAM captured CTCs were immunostained for cytokeratin 18 (CK18) expression, and the optimal fluorescence acquisition intensity was quantified.

Results

The extracorporeal G-EpCAM microchannel device was 3D printed and consisted of an interlocking top lid and bottom base with inlet and outlet channels. The path length of the spiral device consisted of 20 microchannels with a 6.0-foot length. The device accommodated 28 gm of non-hemolytic G-EpCAM compositions. CFD analysis showed 3.8 mm as the ideal channel diameter and 2 mm as the superlative G-EpCAM diameter for maximal cell and CTC capture with minimal blood hemolysis (less than 1%) as compared to the control. Series 1 and 2 devices indicated 90% and 85% cell capture efficiency, respectively, using G-EpCAM devices, indicating the highest interactions and efficiency with cells. Conversely, the first device in the series captured the highest number of cells. In addition, the efficiency improved as the number of G-EpCAM compositions was increased. We accounted for the device to capture CTCs with specificity using the G-EpCAM composition and observed no hemolysis or non-specific interactions with other blood cells like RBCs or leukocytes.

Conclusions

Continuous CTC removal from cancer patients' blood circulation using such a device offers promising therapeutic utility in stemming aggressive metastatic invasion and progression for improving the overall survival of epithelial origin cancer patients.

Clinical Trial Information

CTRI U1111/1192-3951.