CTC isolation using a microfluidic chip.

<p>(A) Design of the CTC microfluidic chip with sinusoidally shaped capture channels and brightfield images of (B) the capillary tube inserted into the on-chip entry channel where whole blood enters the microfluidic chip, (C) sinusoidally shaped capture channels where anti-human EpCAM antibodies are immobilized for CTC capture, (D) exit channel, and (E) impedance sensor with two Pt electrodes located adjacent to the exit channel to detect released CTCs. (F) Cells captured from whole blood of PDX-tumor bearing mice visualized directly on the microfluidic chip following immunostaining with DAPI (blue), human cytokeratin 8/19 (CK, red), and mouse CD45 (green). The staining pattern of DAPI-positive, human CK-positive, and mouse CD45-negative is characteristic of human CTCs. (G) A rare contaminating mouse leukocyte bound non-specifically to the microfluidic chip stained DAPI-positive, human CK-negative, and mouse CD45-positive. Contaminating leukocytes were excluded from enumeration due to the high specificity of the electrical impedance detector for cancer cells.</p

Tumor volume and CTC burden response to treatment.

<p>(-) No data due to microfluidic chip failure.</p

CTC enumeration from PDX-tumor bearing mice.

<p>CTCs captured and enumerated from whole blood of non-tumor and tumor bearing PDX mice. Five non-tumor bearing mice were analyzed for their CTC level (median  = 0 CTCs/250 µL, range  = 0–1 CTCs/250 µL), while CTCs were enumerated from 31 of 31 PDAC PDX mice (median  = 11 CTCs/250 µL, range  = 1–83 CTCs/250 µL) (p = 0.0008, Wilcoxon).</p

Response of CTC burden to BKM120 treatment.

<p>PDAC PDX mice were treated with vehicle or BKM120 for 28 days. CTCs were enumerated from whole blood on day 0 prior to the first treatment and on day 28 after the last treatment. CTC counts significantly decreased in the BKM120 group from pre- to post-treatment (pre-treatment, pre: median  = 26.61 CTCs/250 µL, range  = 7–63 CTCs/250 µL, n = 8; post-treatment, post: median  = 2.21 CTCs/250 µL, range  = 0–79 CTCs/250 µL, n = 8; p = 0.0207, Wilcoxon) while no significant change was observed in the vehicle group (pre: median  = 23.26 CTCs/250 µL, range  = 4–43 CTCs/250 µL, n = 4; post: median  = 11.89 CTCs/250 µL, range  = 6–146 CTCs/250 µL, n = 8; p = 0.8081, Wilcoxon) One post BKM120 treatment sample had no detectable CTCs and is not plotted on scale.</p

Tumor growth inhibition with BKM120 treatment.

<p>BKM120 treatment of PDAC PDX mice for 28 days inhibited tumor growth (Mean fold change, FC  = 1.56; SEM  = 0.148; n = 9) compared to vehicle (mean FC  = 2.16; SEM  = 0.221; n = 8, p = 0.0185, t-test).</p