Metastatic conditioning of myeloid cells at a subcutaneous synthetic niche reflects disease progression and predicts therapeutic outcomes

Microporous polymer (PCL) implants were implanted into BALB/c mice. After 2 weeks mice were inoculated with 4T1 tumor cells. Then after 7, 14, and 21 days the implant and tissue infiltrate which develops into a synthetic niche was biopsied, total RNA was isolated, reverse transcribed into cDNA and analyzed using a high throughput RT-qPCR platform (Applied Biosystems™ TaqMan™ OpenArray™ Mouse Inflammation Panel). The goal of the studies was to identify genes that progressively change at a synthetic site during disease progression. A total of 28 biological replicates were analyzed for the expression of 648 genes. Conditions include 4T1 tumor-bearing (n=14) and healthy time-matched control (n=14) mice analyzed over Days 7 (n=3 per condition), 14 (n=8 per condition), and 21 (n=3 per condition).